超级军网印度人写的关于F-22雷达和电子技术的文章
来源：百度文库 编辑：超级军网 时间：2024/04/29 14:47:49
此文是从一个印度论坛上载抄下来，作者可能是印度在美国的留学生，有可能通过其教授接触到许多F22设计的具体内容。 作者的态度并不妨碍本文的技术专业，此文有很多分析是具体的从信号处理，通讯，还有雷达，导弹科技角度进行。 作者甚至在其大学作过火控系统模拟(图连接在内)。 希望本文给国内专业机构也提供一份借鉴。
由於时间有限，来不及翻译。这里仅提供几点简介：
F22采用了将近5种隐身科技，有：
1。 几何隐身 - 通过飞机外形结构散射雷达信号。
2。 等离子隐身 - 通过由飞机前机翼释放出的电离层来改变飞机的雷达反射特征。
3。 隐身涂料 - 飞机外涂有电子信号吸收材料，已降低反射率。
4。 主动电子信号抵消器 - 飞机能够在受到敌方雷达信号的同时制造出与自身反射波相抵消的主动雷达信号，反射波抵消使得敌方雷达更本收不到信号。
5。 延频，跳频主动相控阵雷达 - 己方雷达即便开机对方的被动雷达信号侦测器也感收不到，感收的到也跟踪不了，跟踪的了也无法及时计算位置。
另外关于F22的AESA雷达信号处理器，其功能强大到能够达到运算速度20亿每秒，更能够扩大到50亿每秒。 而印度将要得到的PHALCON预警机只能达到30亿每秒，俄国的A-50仅能达到10亿每秒。如此强大计算功能使得F22几乎没有跟踪扫描敌方飞机数量的限制。
文中又提到美国的AMRAM 120导弹的借助地球重力加速的方法，此方法使得导弹的增程和速度远远超过俄国的R77。
对此，作者的结论是地球上现今任何一种战斗机都无法对付F22，包括阵风，EF2000， 俄国的SU-30MKI/SU-37，更不要说中国的J-10。
Posted: Mon Nov 17, 2003 9:50 am Post subject:
--------------------------------------------------------------------------------
Quote:
TWR = Maximum Thrust/Typical Takeoff Load
Come on what is TYPICAL TAKE OFF WEIGHT , a f-15 can carry two aim-9x and two aim-120 as “typical Take off weight” and a MKI can carry a salvo of AAM’s as “typical Take off weight” , in war circumstances there is NO “typical Take off weight” ,it all depends on the sotie get me? That is why to compare TWR people use my formula [janes Uses Maximum Thrust/Empty weight+ unusable fuel +half internal fuel , no way for me to know the amount of unusable fuel so I left it and Janes is the leaders in civilian military intelligence and their figures are always correct and if you do not have access to Janes then it is not my problem and FAS is never updated and that is a great problem there though FAS is great for Navy , their airforce info is woefully inadequate ] because the TWR’s of all kind of jets can be compared irrespective of type of weapons and the weapons weight get me ? That is why my formulae holds a better way of comparison .
Then why do you change your Twr in every post ? does the real TWR very like this ?
Quote:
Here is some information about the Su-30MKI/Su-37,
The su-37 is NOT THE MKI. GET YOUR FACTS RIGHT AVAINASH. Entire airframe ,engines,FCS is different and never ever FAS mentions that MKI is SU-37 and please do not CCP from FAS I have already posted enough on radars , so please read my previous posts [ I know and all know FAS]
Quote:
This proves that the Su-30MKI/Su-37 is quite a structurally unstable aircraft
What proves that MKI=SU-37 , just show me one link to prove that MKI=Terminator , and the airframe on MKI is no where near un stability offered by Full digital FCS planes
Quote:
I did some research on the Fly By Wire systems on the Flanker series of aircraft. The SDU-10MK remote control system is a triplex system that is used on the Su-27 and the SU-30MKK
Your research sucks , I had already told you all flankers use a quadraplex analog and not triplex.
Quote:
However the SU-30MKI and the Su-37 use the Quadruplex Digital Flight Control System tested on the Su-35
Totally baseless , let me put things in perspective , engg developed FBW for Su-35 that they removed the TVC from the base line Su-37 and MKI uses a Hybrid analog digital and not a True digital , neither FAS nor Janes and even BR does not say “Quadruplex Digital Flight Control” but only It only said it's quadruplex like I said visit MAKS2003 it clearly mentions that “The SDU-10MK remote control system is a digital- analogue system and is an exchange for the mechanical control circuit.The system ensures a high efficiency level of an airplane (at the expense of automatic limiting of marginal flight modes, control of an airplane both through basic, and auxiliary control surfaces, stability and controllability with the help of SDU contours used in MKI.” You ought to know that Russians know best about their weapons. And just for you SU-30 MKI is not Su-37.
Quote:
I dont understand how this design could be characterized by low lift or drag
Read my reply more carefully I said because of less use of composites and a 25 year old airframe , The airframe induces Drag [ read the posts more carefully]
Quote:
because of its large wing (666 square feet, excluding the canards, compared to the Eurofighter's wing + canard area of 563 square feet)
What is the weight of the Ef2000 and MKI you get the answer
Quote:
did some research on engines, and from the charts i saw, the Al-31FP provides marginally better bypass ratios at speeds in excess of mach .9 (according to the chart) than the F-100 series used on the F-15 family.
What charts ? I thought of posting those but then just to prove that you are not bluffing would you mind explaining a bit about those?
And next time please try to pose some challenge alright? And not just CCP.
.
Quote:
I am going to track raptor using IRST
Got to tell you guys , this is a totally silly statement . Heared anything called as “Resolution” in IRST ? guess not , if you guys had this statement would have never come , just wait for a few more replies where I would post a bit on IRST finally [ too many unfinished business left before hand which includes escaping from a missile using ECM]
Quote:
Russians avionics are as advanced as west
Yes but of course , after all they developed sensor fusion ,AESA , touch sensitive multi colured MFD’s, Data Links , Active Echo cancellers , Stealth …………etc and even more advanced that India prefers to use Israeli+Indian+French Avionics and not a Hint of Russian , you Tell me exactly where does any Russian avionics stand up to a jet like M2000/Rafale/Grippen/Ef2000…..etc [ no bs here this is my territory and forget the raptor nobody is near] as I said they are so pathetically poor that they use civilian MFD’s one their Jets and even in the cold war they were no were near and now after everything has crumbled they are able to counter the West ?
Let Me repeat the MKI never even stands up near EF2000 or Rafale and I have already proved this , if possible counter these arguments with TECHNICAL REPLY’s AND NOT JUST CCP [ be a bit professional alright ? ]
Radars
The design of an antenna is conditioned by the required coverage , it should be remembered that antennas are one of the key elements in a radar system their gain values directly determine the amount of recieved power , the characterictics required are gain [ maximum value of gain pattern ] and beamwidth [measure of angle over which most of the gain occurs ] , here the antenna should be highly directional with high gain margin concentrated over a narrow beamwidth with negligibly small side lobe transmission.
The antenna types are [ as previously said] maybe linear dipole ,horn, antenna array and the parabolic reflector .
parabolic reflector is commonly used as it gives a highly symmetric pattern .The dipole produces a radiation pattern that is hemispherical .Helix and horn antennas also are of small sizes[ micro meter] also produce reasonable directivity , but this antennas have several sidelobes much higher than parabolic reflector .An array consisting of group of small antennas such as dipoles , horns or helices produce a combined beam with directivity also by properly selecting the phase shift between array elements the directivity of the beam may be oriented in a given direction, also gain of the array elements with the number of array elements and hence a high gain with large arrays .also here beam width changes with beam direction , being narrowest for broadside beams and larger for axis beams ,thus the importance.
Final Reply on AESA [ Warning : Those who do not like U.S.A might get a heart attack!!!!!!!!]
Quote:
Is LPI synonymous with AESA rite
Yep Aesa is means LPI and what else to take into account than the Raptor’s AESA I shall be saying about the advantages of AESA , first as I said AESA employs Spread Spectrum [ more in the end for techies] , lets see a bit about the raptor’s INVINCIBLE Radar Apg/An-77 is made of active elements , electronic scanning , non moving arrays of t’xr cum R’xr modules .Each of these finger shaped modules weighs about 15 gms and has a power o/p of 4 Watts.The radar can change the direction ,power and shape of the beam in a fraction of a second to minimize chances of dedection .An f-22 has one forward looking array and two sides giving it an unprecedented range and also the radar employs Spread Spectrum making it Virtually impossible to detect.
Sensor fusion in Raptor:
As I said before he biggest advantage of EF2000, Rafale over MKI is Sensor fusion ,lets see a bit about the raptors sensor fusion also note that sensor fusion is developed with the aircraft and NOT UPGRADES thus no way MKI is going to have sensor fusion , anyway going back to Raptor , all the raptor Radar , avionics ……..etc is controlled by a two huges built CIP’s [ common integrated processors ] . The CIP is the brain of the F-22 avionics which work as a integrated unit .The CIP collets and processes all data and signature from different sensors of the craft correlating all the different info as a single entity thus providing better dedection because all the RADAR , RWR , IRST…….etc are correlated and CIP is also responsible for managing the Active Echo Cancellers which are used to cancel he signals Falling on it , for this the two CIP’s with 66 modules each.Only 75% of their capab is used as of now and 41 slots remain for future upgrades .There is a provision of adding 66 modules in case of drastic upgrade.The processing capacity of CIP is rated at more than 700 MIPS that can be upgraded to 2000 MIPS . Similarly its signal processing capacitiy is rated at more than 20 bops [ billions operations per second ] and can be expanded to 50 bops [ PHALCON has a 30 bops and I heared [ not sure ] that A-50 has 10 bops ,hope this tells you the extent of signal processing capacity of Raptor which is required because of AESA radar and Active Echo Cancellers present ] .
The integrated nature of the avionics means that all relevant info can be got from a single source through a number of MFD’s .The IT part of MFD is explained by the nVIDIA Quadro 2 Go GPU and Wind Rivers Vx works Os.
The avionics system is built 1.7 million codes of which 90% is written in ADA .The software is made up of three complementing blocks .Block 1 contains more than 50% of the avionics Full Functionality code , though its main function is radar capability . Very important and intresting is that redundancy built in . Should any part fail at any point of operation another module automatically kicks in.If CIP module that is actimg as the radio or Radar die/hang up one of the other modules will automatically reload the program and take over radio …etc and finally raptor was fully simulated before even the “hard” mock up of F-22!!!!!!! Sounds fascinating doesn’t it ?此文是从一个印度论坛上载抄下来，作者可能是印度在美国的留学生，有可能通过其教授接触到许多F22设计的具体内容。 作者的态度并不妨碍本文的技术专业，此文有很多分析是具体的从信号处理，通讯，还有雷达，导弹科技角度进行。 作者甚至在其大学作过火控系统模拟(图连接在内)。 希望本文给国内专业机构也提供一份借鉴。
由於时间有限，来不及翻译。这里仅提供几点简介：
F22采用了将近5种隐身科技，有：
1。 几何隐身 - 通过飞机外形结构散射雷达信号。
2。 等离子隐身 - 通过由飞机前机翼释放出的电离层来改变飞机的雷达反射特征。
3。 隐身涂料 - 飞机外涂有电子信号吸收材料，已降低反射率。
4。 主动电子信号抵消器 - 飞机能够在受到敌方雷达信号的同时制造出与自身反射波相抵消的主动雷达信号，反射波抵消使得敌方雷达更本收不到信号。
5。 延频，跳频主动相控阵雷达 - 己方雷达即便开机对方的被动雷达信号侦测器也感收不到，感收的到也跟踪不了，跟踪的了也无法及时计算位置。
另外关于F22的AESA雷达信号处理器，其功能强大到能够达到运算速度20亿每秒，更能够扩大到50亿每秒。 而印度将要得到的PHALCON预警机只能达到30亿每秒，俄国的A-50仅能达到10亿每秒。如此强大计算功能使得F22几乎没有跟踪扫描敌方飞机数量的限制。
文中又提到美国的AMRAM 120导弹的借助地球重力加速的方法，此方法使得导弹的增程和速度远远超过俄国的R77。
对此，作者的结论是地球上现今任何一种战斗机都无法对付F22，包括阵风，EF2000， 俄国的SU-30MKI/SU-37，更不要说中国的J-10。
Posted: Mon Nov 17, 2003 9:50 am Post subject:
--------------------------------------------------------------------------------
Quote:
TWR = Maximum Thrust/Typical Takeoff Load
Come on what is TYPICAL TAKE OFF WEIGHT , a f-15 can carry two aim-9x and two aim-120 as “typical Take off weight” and a MKI can carry a salvo of AAM’s as “typical Take off weight” , in war circumstances there is NO “typical Take off weight” ,it all depends on the sotie get me? That is why to compare TWR people use my formula [janes Uses Maximum Thrust/Empty weight+ unusable fuel +half internal fuel , no way for me to know the amount of unusable fuel so I left it and Janes is the leaders in civilian military intelligence and their figures are always correct and if you do not have access to Janes then it is not my problem and FAS is never updated and that is a great problem there though FAS is great for Navy , their airforce info is woefully inadequate ] because the TWR’s of all kind of jets can be compared irrespective of type of weapons and the weapons weight get me ? That is why my formulae holds a better way of comparison .
Then why do you change your Twr in every post ? does the real TWR very like this ?
Quote:
Here is some information about the Su-30MKI/Su-37,
The su-37 is NOT THE MKI. GET YOUR FACTS RIGHT AVAINASH. Entire airframe ,engines,FCS is different and never ever FAS mentions that MKI is SU-37 and please do not CCP from FAS I have already posted enough on radars , so please read my previous posts [ I know and all know FAS]
Quote:
This proves that the Su-30MKI/Su-37 is quite a structurally unstable aircraft
What proves that MKI=SU-37 , just show me one link to prove that MKI=Terminator , and the airframe on MKI is no where near un stability offered by Full digital FCS planes
Quote:
I did some research on the Fly By Wire systems on the Flanker series of aircraft. The SDU-10MK remote control system is a triplex system that is used on the Su-27 and the SU-30MKK
Your research sucks , I had already told you all flankers use a quadraplex analog and not triplex.
Quote:
However the SU-30MKI and the Su-37 use the Quadruplex Digital Flight Control System tested on the Su-35
Totally baseless , let me put things in perspective , engg developed FBW for Su-35 that they removed the TVC from the base line Su-37 and MKI uses a Hybrid analog digital and not a True digital , neither FAS nor Janes and even BR does not say “Quadruplex Digital Flight Control” but only It only said it's quadruplex like I said visit MAKS2003 it clearly mentions that “The SDU-10MK remote control system is a digital- analogue system and is an exchange for the mechanical control circuit.The system ensures a high efficiency level of an airplane (at the expense of automatic limiting of marginal flight modes, control of an airplane both through basic, and auxiliary control surfaces, stability and controllability with the help of SDU contours used in MKI.” You ought to know that Russians know best about their weapons. And just for you SU-30 MKI is not Su-37.
Quote:
I dont understand how this design could be characterized by low lift or drag
Read my reply more carefully I said because of less use of composites and a 25 year old airframe , The airframe induces Drag [ read the posts more carefully]
Quote:
because of its large wing (666 square feet, excluding the canards, compared to the Eurofighter's wing + canard area of 563 square feet)
What is the weight of the Ef2000 and MKI you get the answer
Quote:
did some research on engines, and from the charts i saw, the Al-31FP provides marginally better bypass ratios at speeds in excess of mach .9 (according to the chart) than the F-100 series used on the F-15 family.
What charts ? I thought of posting those but then just to prove that you are not bluffing would you mind explaining a bit about those?
And next time please try to pose some challenge alright? And not just CCP.
.
Quote:
I am going to track raptor using IRST
Got to tell you guys , this is a totally silly statement . Heared anything called as “Resolution” in IRST ? guess not , if you guys had this statement would have never come , just wait for a few more replies where I would post a bit on IRST finally [ too many unfinished business left before hand which includes escaping from a missile using ECM]
Quote:
Russians avionics are as advanced as west
Yes but of course , after all they developed sensor fusion ,AESA , touch sensitive multi colured MFD’s, Data Links , Active Echo cancellers , Stealth …………etc and even more advanced that India prefers to use Israeli+Indian+French Avionics and not a Hint of Russian , you Tell me exactly where does any Russian avionics stand up to a jet like M2000/Rafale/Grippen/Ef2000…..etc [ no bs here this is my territory and forget the raptor nobody is near] as I said they are so pathetically poor that they use civilian MFD’s one their Jets and even in the cold war they were no were near and now after everything has crumbled they are able to counter the West ?
Let Me repeat the MKI never even stands up near EF2000 or Rafale and I have already proved this , if possible counter these arguments with TECHNICAL REPLY’s AND NOT JUST CCP [ be a bit professional alright ? ]
Radars
The design of an antenna is conditioned by the required coverage , it should be remembered that antennas are one of the key elements in a radar system their gain values directly determine the amount of recieved power , the characterictics required are gain [ maximum value of gain pattern ] and beamwidth [measure of angle over which most of the gain occurs ] , here the antenna should be highly directional with high gain margin concentrated over a narrow beamwidth with negligibly small side lobe transmission.
The antenna types are [ as previously said] maybe linear dipole ,horn, antenna array and the parabolic reflector .
parabolic reflector is commonly used as it gives a highly symmetric pattern .The dipole produces a radiation pattern that is hemispherical .Helix and horn antennas also are of small sizes[ micro meter] also produce reasonable directivity , but this antennas have several sidelobes much higher than parabolic reflector .An array consisting of group of small antennas such as dipoles , horns or helices produce a combined beam with directivity also by properly selecting the phase shift between array elements the directivity of the beam may be oriented in a given direction, also gain of the array elements with the number of array elements and hence a high gain with large arrays .also here beam width changes with beam direction , being narrowest for broadside beams and larger for axis beams ,thus the importance.
Final Reply on AESA [ Warning : Those who do not like U.S.A might get a heart attack!!!!!!!!]
Quote:
Is LPI synonymous with AESA rite
Yep Aesa is means LPI and what else to take into account than the Raptor’s AESA I shall be saying about the advantages of AESA , first as I said AESA employs Spread Spectrum [ more in the end for techies] , lets see a bit about the raptor’s INVINCIBLE Radar Apg/An-77 is made of active elements , electronic scanning , non moving arrays of t’xr cum R’xr modules .Each of these finger shaped modules weighs about 15 gms and has a power o/p of 4 Watts.The radar can change the direction ,power and shape of the beam in a fraction of a second to minimize chances of dedection .An f-22 has one forward looking array and two sides giving it an unprecedented range and also the radar employs Spread Spectrum making it Virtually impossible to detect.
Sensor fusion in Raptor:
As I said before he biggest advantage of EF2000, Rafale over MKI is Sensor fusion ,lets see a bit about the raptors sensor fusion also note that sensor fusion is developed with the aircraft and NOT UPGRADES thus no way MKI is going to have sensor fusion , anyway going back to Raptor , all the raptor Radar , avionics ……..etc is controlled by a two huges built CIP’s [ common integrated processors ] . The CIP is the brain of the F-22 avionics which work as a integrated unit .The CIP collets and processes all data and signature from different sensors of the craft correlating all the different info as a single entity thus providing better dedection because all the RADAR , RWR , IRST…….etc are correlated and CIP is also responsible for managing the Active Echo Cancellers which are used to cancel he signals Falling on it , for this the two CIP’s with 66 modules each.Only 75% of their capab is used as of now and 41 slots remain for future upgrades .There is a provision of adding 66 modules in case of drastic upgrade.The processing capacity of CIP is rated at more than 700 MIPS that can be upgraded to 2000 MIPS . Similarly its signal processing capacitiy is rated at more than 20 bops [ billions operations per second ] and can be expanded to 50 bops [ PHALCON has a 30 bops and I heared [ not sure ] that A-50 has 10 bops ,hope this tells you the extent of signal processing capacity of Raptor which is required because of AESA radar and Active Echo Cancellers present ] .
The integrated nature of the avionics means that all relevant info can be got from a single source through a number of MFD’s .The IT part of MFD is explained by the nVIDIA Quadro 2 Go GPU and Wind Rivers Vx works Os.
The avionics system is built 1.7 million codes of which 90% is written in ADA .The software is made up of three complementing blocks .Block 1 contains more than 50% of the avionics Full Functionality code , though its main function is radar capability . Very important and intresting is that redundancy built in . Should any part fail at any point of operation another module automatically kicks in.If CIP module that is actimg as the radio or Radar die/hang up one of the other modules will automatically reload the program and take over radio …etc and finally raptor was fully simulated before even the “hard” mock up of F-22!!!!!!! Sounds fascinating doesn’t it ?
由於时间有限，来不及翻译。这里仅提供几点简介：
F22采用了将近5种隐身科技，有：
1。 几何隐身 - 通过飞机外形结构散射雷达信号。
2。 等离子隐身 - 通过由飞机前机翼释放出的电离层来改变飞机的雷达反射特征。
3。 隐身涂料 - 飞机外涂有电子信号吸收材料，已降低反射率。
4。 主动电子信号抵消器 - 飞机能够在受到敌方雷达信号的同时制造出与自身反射波相抵消的主动雷达信号，反射波抵消使得敌方雷达更本收不到信号。
5。 延频，跳频主动相控阵雷达 - 己方雷达即便开机对方的被动雷达信号侦测器也感收不到，感收的到也跟踪不了，跟踪的了也无法及时计算位置。
另外关于F22的AESA雷达信号处理器，其功能强大到能够达到运算速度20亿每秒，更能够扩大到50亿每秒。 而印度将要得到的PHALCON预警机只能达到30亿每秒，俄国的A-50仅能达到10亿每秒。如此强大计算功能使得F22几乎没有跟踪扫描敌方飞机数量的限制。
文中又提到美国的AMRAM 120导弹的借助地球重力加速的方法，此方法使得导弹的增程和速度远远超过俄国的R77。
对此，作者的结论是地球上现今任何一种战斗机都无法对付F22，包括阵风，EF2000， 俄国的SU-30MKI/SU-37，更不要说中国的J-10。
Posted: Mon Nov 17, 2003 9:50 am Post subject:
--------------------------------------------------------------------------------
Quote:
TWR = Maximum Thrust/Typical Takeoff Load
Come on what is TYPICAL TAKE OFF WEIGHT , a f-15 can carry two aim-9x and two aim-120 as “typical Take off weight” and a MKI can carry a salvo of AAM’s as “typical Take off weight” , in war circumstances there is NO “typical Take off weight” ,it all depends on the sotie get me? That is why to compare TWR people use my formula [janes Uses Maximum Thrust/Empty weight+ unusable fuel +half internal fuel , no way for me to know the amount of unusable fuel so I left it and Janes is the leaders in civilian military intelligence and their figures are always correct and if you do not have access to Janes then it is not my problem and FAS is never updated and that is a great problem there though FAS is great for Navy , their airforce info is woefully inadequate ] because the TWR’s of all kind of jets can be compared irrespective of type of weapons and the weapons weight get me ? That is why my formulae holds a better way of comparison .
Then why do you change your Twr in every post ? does the real TWR very like this ?
Quote:
Here is some information about the Su-30MKI/Su-37,
The su-37 is NOT THE MKI. GET YOUR FACTS RIGHT AVAINASH. Entire airframe ,engines,FCS is different and never ever FAS mentions that MKI is SU-37 and please do not CCP from FAS I have already posted enough on radars , so please read my previous posts [ I know and all know FAS]
Quote:
This proves that the Su-30MKI/Su-37 is quite a structurally unstable aircraft
What proves that MKI=SU-37 , just show me one link to prove that MKI=Terminator , and the airframe on MKI is no where near un stability offered by Full digital FCS planes
Quote:
I did some research on the Fly By Wire systems on the Flanker series of aircraft. The SDU-10MK remote control system is a triplex system that is used on the Su-27 and the SU-30MKK
Your research sucks , I had already told you all flankers use a quadraplex analog and not triplex.
Quote:
However the SU-30MKI and the Su-37 use the Quadruplex Digital Flight Control System tested on the Su-35
Totally baseless , let me put things in perspective , engg developed FBW for Su-35 that they removed the TVC from the base line Su-37 and MKI uses a Hybrid analog digital and not a True digital , neither FAS nor Janes and even BR does not say “Quadruplex Digital Flight Control” but only It only said it's quadruplex like I said visit MAKS2003 it clearly mentions that “The SDU-10MK remote control system is a digital- analogue system and is an exchange for the mechanical control circuit.The system ensures a high efficiency level of an airplane (at the expense of automatic limiting of marginal flight modes, control of an airplane both through basic, and auxiliary control surfaces, stability and controllability with the help of SDU contours used in MKI.” You ought to know that Russians know best about their weapons. And just for you SU-30 MKI is not Su-37.
Quote:
I dont understand how this design could be characterized by low lift or drag
Read my reply more carefully I said because of less use of composites and a 25 year old airframe , The airframe induces Drag [ read the posts more carefully]
Quote:
because of its large wing (666 square feet, excluding the canards, compared to the Eurofighter's wing + canard area of 563 square feet)
What is the weight of the Ef2000 and MKI you get the answer
Quote:
did some research on engines, and from the charts i saw, the Al-31FP provides marginally better bypass ratios at speeds in excess of mach .9 (according to the chart) than the F-100 series used on the F-15 family.
What charts ? I thought of posting those but then just to prove that you are not bluffing would you mind explaining a bit about those?
And next time please try to pose some challenge alright? And not just CCP.
.
Quote:
I am going to track raptor using IRST
Got to tell you guys , this is a totally silly statement . Heared anything called as “Resolution” in IRST ? guess not , if you guys had this statement would have never come , just wait for a few more replies where I would post a bit on IRST finally [ too many unfinished business left before hand which includes escaping from a missile using ECM]
Quote:
Russians avionics are as advanced as west
Yes but of course , after all they developed sensor fusion ,AESA , touch sensitive multi colured MFD’s, Data Links , Active Echo cancellers , Stealth …………etc and even more advanced that India prefers to use Israeli+Indian+French Avionics and not a Hint of Russian , you Tell me exactly where does any Russian avionics stand up to a jet like M2000/Rafale/Grippen/Ef2000…..etc [ no bs here this is my territory and forget the raptor nobody is near] as I said they are so pathetically poor that they use civilian MFD’s one their Jets and even in the cold war they were no were near and now after everything has crumbled they are able to counter the West ?
Let Me repeat the MKI never even stands up near EF2000 or Rafale and I have already proved this , if possible counter these arguments with TECHNICAL REPLY’s AND NOT JUST CCP [ be a bit professional alright ? ]
Radars
The design of an antenna is conditioned by the required coverage , it should be remembered that antennas are one of the key elements in a radar system their gain values directly determine the amount of recieved power , the characterictics required are gain [ maximum value of gain pattern ] and beamwidth [measure of angle over which most of the gain occurs ] , here the antenna should be highly directional with high gain margin concentrated over a narrow beamwidth with negligibly small side lobe transmission.
The antenna types are [ as previously said] maybe linear dipole ,horn, antenna array and the parabolic reflector .
parabolic reflector is commonly used as it gives a highly symmetric pattern .The dipole produces a radiation pattern that is hemispherical .Helix and horn antennas also are of small sizes[ micro meter] also produce reasonable directivity , but this antennas have several sidelobes much higher than parabolic reflector .An array consisting of group of small antennas such as dipoles , horns or helices produce a combined beam with directivity also by properly selecting the phase shift between array elements the directivity of the beam may be oriented in a given direction, also gain of the array elements with the number of array elements and hence a high gain with large arrays .also here beam width changes with beam direction , being narrowest for broadside beams and larger for axis beams ,thus the importance.
Final Reply on AESA [ Warning : Those who do not like U.S.A might get a heart attack!!!!!!!!]
Quote:
Is LPI synonymous with AESA rite
Yep Aesa is means LPI and what else to take into account than the Raptor’s AESA I shall be saying about the advantages of AESA , first as I said AESA employs Spread Spectrum [ more in the end for techies] , lets see a bit about the raptor’s INVINCIBLE Radar Apg/An-77 is made of active elements , electronic scanning , non moving arrays of t’xr cum R’xr modules .Each of these finger shaped modules weighs about 15 gms and has a power o/p of 4 Watts.The radar can change the direction ,power and shape of the beam in a fraction of a second to minimize chances of dedection .An f-22 has one forward looking array and two sides giving it an unprecedented range and also the radar employs Spread Spectrum making it Virtually impossible to detect.
Sensor fusion in Raptor:
As I said before he biggest advantage of EF2000, Rafale over MKI is Sensor fusion ,lets see a bit about the raptors sensor fusion also note that sensor fusion is developed with the aircraft and NOT UPGRADES thus no way MKI is going to have sensor fusion , anyway going back to Raptor , all the raptor Radar , avionics ……..etc is controlled by a two huges built CIP’s [ common integrated processors ] . The CIP is the brain of the F-22 avionics which work as a integrated unit .The CIP collets and processes all data and signature from different sensors of the craft correlating all the different info as a single entity thus providing better dedection because all the RADAR , RWR , IRST…….etc are correlated and CIP is also responsible for managing the Active Echo Cancellers which are used to cancel he signals Falling on it , for this the two CIP’s with 66 modules each.Only 75% of their capab is used as of now and 41 slots remain for future upgrades .There is a provision of adding 66 modules in case of drastic upgrade.The processing capacity of CIP is rated at more than 700 MIPS that can be upgraded to 2000 MIPS . Similarly its signal processing capacitiy is rated at more than 20 bops [ billions operations per second ] and can be expanded to 50 bops [ PHALCON has a 30 bops and I heared [ not sure ] that A-50 has 10 bops ,hope this tells you the extent of signal processing capacity of Raptor which is required because of AESA radar and Active Echo Cancellers present ] .
The integrated nature of the avionics means that all relevant info can be got from a single source through a number of MFD’s .The IT part of MFD is explained by the nVIDIA Quadro 2 Go GPU and Wind Rivers Vx works Os.
The avionics system is built 1.7 million codes of which 90% is written in ADA .The software is made up of three complementing blocks .Block 1 contains more than 50% of the avionics Full Functionality code , though its main function is radar capability . Very important and intresting is that redundancy built in . Should any part fail at any point of operation another module automatically kicks in.If CIP module that is actimg as the radio or Radar die/hang up one of the other modules will automatically reload the program and take over radio …etc and finally raptor was fully simulated before even the “hard” mock up of F-22!!!!!!! Sounds fascinating doesn’t it ?此文是从一个印度论坛上载抄下来，作者可能是印度在美国的留学生，有可能通过其教授接触到许多F22设计的具体内容。 作者的态度并不妨碍本文的技术专业，此文有很多分析是具体的从信号处理，通讯，还有雷达，导弹科技角度进行。 作者甚至在其大学作过火控系统模拟(图连接在内)。 希望本文给国内专业机构也提供一份借鉴。
由於时间有限，来不及翻译。这里仅提供几点简介：
F22采用了将近5种隐身科技，有：
1。 几何隐身 - 通过飞机外形结构散射雷达信号。
2。 等离子隐身 - 通过由飞机前机翼释放出的电离层来改变飞机的雷达反射特征。
3。 隐身涂料 - 飞机外涂有电子信号吸收材料，已降低反射率。
4。 主动电子信号抵消器 - 飞机能够在受到敌方雷达信号的同时制造出与自身反射波相抵消的主动雷达信号，反射波抵消使得敌方雷达更本收不到信号。
5。 延频，跳频主动相控阵雷达 - 己方雷达即便开机对方的被动雷达信号侦测器也感收不到，感收的到也跟踪不了，跟踪的了也无法及时计算位置。
另外关于F22的AESA雷达信号处理器，其功能强大到能够达到运算速度20亿每秒，更能够扩大到50亿每秒。 而印度将要得到的PHALCON预警机只能达到30亿每秒，俄国的A-50仅能达到10亿每秒。如此强大计算功能使得F22几乎没有跟踪扫描敌方飞机数量的限制。
文中又提到美国的AMRAM 120导弹的借助地球重力加速的方法，此方法使得导弹的增程和速度远远超过俄国的R77。
对此，作者的结论是地球上现今任何一种战斗机都无法对付F22，包括阵风，EF2000， 俄国的SU-30MKI/SU-37，更不要说中国的J-10。
Posted: Mon Nov 17, 2003 9:50 am Post subject:
--------------------------------------------------------------------------------
Quote:
TWR = Maximum Thrust/Typical Takeoff Load
Come on what is TYPICAL TAKE OFF WEIGHT , a f-15 can carry two aim-9x and two aim-120 as “typical Take off weight” and a MKI can carry a salvo of AAM’s as “typical Take off weight” , in war circumstances there is NO “typical Take off weight” ,it all depends on the sotie get me? That is why to compare TWR people use my formula [janes Uses Maximum Thrust/Empty weight+ unusable fuel +half internal fuel , no way for me to know the amount of unusable fuel so I left it and Janes is the leaders in civilian military intelligence and their figures are always correct and if you do not have access to Janes then it is not my problem and FAS is never updated and that is a great problem there though FAS is great for Navy , their airforce info is woefully inadequate ] because the TWR’s of all kind of jets can be compared irrespective of type of weapons and the weapons weight get me ? That is why my formulae holds a better way of comparison .
Then why do you change your Twr in every post ? does the real TWR very like this ?
Quote:
Here is some information about the Su-30MKI/Su-37,
The su-37 is NOT THE MKI. GET YOUR FACTS RIGHT AVAINASH. Entire airframe ,engines,FCS is different and never ever FAS mentions that MKI is SU-37 and please do not CCP from FAS I have already posted enough on radars , so please read my previous posts [ I know and all know FAS]
Quote:
This proves that the Su-30MKI/Su-37 is quite a structurally unstable aircraft
What proves that MKI=SU-37 , just show me one link to prove that MKI=Terminator , and the airframe on MKI is no where near un stability offered by Full digital FCS planes
Quote:
I did some research on the Fly By Wire systems on the Flanker series of aircraft. The SDU-10MK remote control system is a triplex system that is used on the Su-27 and the SU-30MKK
Your research sucks , I had already told you all flankers use a quadraplex analog and not triplex.
Quote:
However the SU-30MKI and the Su-37 use the Quadruplex Digital Flight Control System tested on the Su-35
Totally baseless , let me put things in perspective , engg developed FBW for Su-35 that they removed the TVC from the base line Su-37 and MKI uses a Hybrid analog digital and not a True digital , neither FAS nor Janes and even BR does not say “Quadruplex Digital Flight Control” but only It only said it's quadruplex like I said visit MAKS2003 it clearly mentions that “The SDU-10MK remote control system is a digital- analogue system and is an exchange for the mechanical control circuit.The system ensures a high efficiency level of an airplane (at the expense of automatic limiting of marginal flight modes, control of an airplane both through basic, and auxiliary control surfaces, stability and controllability with the help of SDU contours used in MKI.” You ought to know that Russians know best about their weapons. And just for you SU-30 MKI is not Su-37.
Quote:
I dont understand how this design could be characterized by low lift or drag
Read my reply more carefully I said because of less use of composites and a 25 year old airframe , The airframe induces Drag [ read the posts more carefully]
Quote:
because of its large wing (666 square feet, excluding the canards, compared to the Eurofighter's wing + canard area of 563 square feet)
What is the weight of the Ef2000 and MKI you get the answer
Quote:
did some research on engines, and from the charts i saw, the Al-31FP provides marginally better bypass ratios at speeds in excess of mach .9 (according to the chart) than the F-100 series used on the F-15 family.
What charts ? I thought of posting those but then just to prove that you are not bluffing would you mind explaining a bit about those?
And next time please try to pose some challenge alright? And not just CCP.
.
Quote:
I am going to track raptor using IRST
Got to tell you guys , this is a totally silly statement . Heared anything called as “Resolution” in IRST ? guess not , if you guys had this statement would have never come , just wait for a few more replies where I would post a bit on IRST finally [ too many unfinished business left before hand which includes escaping from a missile using ECM]
Quote:
Russians avionics are as advanced as west
Yes but of course , after all they developed sensor fusion ,AESA , touch sensitive multi colured MFD’s, Data Links , Active Echo cancellers , Stealth …………etc and even more advanced that India prefers to use Israeli+Indian+French Avionics and not a Hint of Russian , you Tell me exactly where does any Russian avionics stand up to a jet like M2000/Rafale/Grippen/Ef2000…..etc [ no bs here this is my territory and forget the raptor nobody is near] as I said they are so pathetically poor that they use civilian MFD’s one their Jets and even in the cold war they were no were near and now after everything has crumbled they are able to counter the West ?
Let Me repeat the MKI never even stands up near EF2000 or Rafale and I have already proved this , if possible counter these arguments with TECHNICAL REPLY’s AND NOT JUST CCP [ be a bit professional alright ? ]
Radars
The design of an antenna is conditioned by the required coverage , it should be remembered that antennas are one of the key elements in a radar system their gain values directly determine the amount of recieved power , the characterictics required are gain [ maximum value of gain pattern ] and beamwidth [measure of angle over which most of the gain occurs ] , here the antenna should be highly directional with high gain margin concentrated over a narrow beamwidth with negligibly small side lobe transmission.
The antenna types are [ as previously said] maybe linear dipole ,horn, antenna array and the parabolic reflector .
parabolic reflector is commonly used as it gives a highly symmetric pattern .The dipole produces a radiation pattern that is hemispherical .Helix and horn antennas also are of small sizes[ micro meter] also produce reasonable directivity , but this antennas have several sidelobes much higher than parabolic reflector .An array consisting of group of small antennas such as dipoles , horns or helices produce a combined beam with directivity also by properly selecting the phase shift between array elements the directivity of the beam may be oriented in a given direction, also gain of the array elements with the number of array elements and hence a high gain with large arrays .also here beam width changes with beam direction , being narrowest for broadside beams and larger for axis beams ,thus the importance.
Final Reply on AESA [ Warning : Those who do not like U.S.A might get a heart attack!!!!!!!!]
Quote:
Is LPI synonymous with AESA rite
Yep Aesa is means LPI and what else to take into account than the Raptor’s AESA I shall be saying about the advantages of AESA , first as I said AESA employs Spread Spectrum [ more in the end for techies] , lets see a bit about the raptor’s INVINCIBLE Radar Apg/An-77 is made of active elements , electronic scanning , non moving arrays of t’xr cum R’xr modules .Each of these finger shaped modules weighs about 15 gms and has a power o/p of 4 Watts.The radar can change the direction ,power and shape of the beam in a fraction of a second to minimize chances of dedection .An f-22 has one forward looking array and two sides giving it an unprecedented range and also the radar employs Spread Spectrum making it Virtually impossible to detect.
Sensor fusion in Raptor:
As I said before he biggest advantage of EF2000, Rafale over MKI is Sensor fusion ,lets see a bit about the raptors sensor fusion also note that sensor fusion is developed with the aircraft and NOT UPGRADES thus no way MKI is going to have sensor fusion , anyway going back to Raptor , all the raptor Radar , avionics ……..etc is controlled by a two huges built CIP’s [ common integrated processors ] . The CIP is the brain of the F-22 avionics which work as a integrated unit .The CIP collets and processes all data and signature from different sensors of the craft correlating all the different info as a single entity thus providing better dedection because all the RADAR , RWR , IRST…….etc are correlated and CIP is also responsible for managing the Active Echo Cancellers which are used to cancel he signals Falling on it , for this the two CIP’s with 66 modules each.Only 75% of their capab is used as of now and 41 slots remain for future upgrades .There is a provision of adding 66 modules in case of drastic upgrade.The processing capacity of CIP is rated at more than 700 MIPS that can be upgraded to 2000 MIPS . Similarly its signal processing capacitiy is rated at more than 20 bops [ billions operations per second ] and can be expanded to 50 bops [ PHALCON has a 30 bops and I heared [ not sure ] that A-50 has 10 bops ,hope this tells you the extent of signal processing capacity of Raptor which is required because of AESA radar and Active Echo Cancellers present ] .
The integrated nature of the avionics means that all relevant info can be got from a single source through a number of MFD’s .The IT part of MFD is explained by the nVIDIA Quadro 2 Go GPU and Wind Rivers Vx works Os.
The avionics system is built 1.7 million codes of which 90% is written in ADA .The software is made up of three complementing blocks .Block 1 contains more than 50% of the avionics Full Functionality code , though its main function is radar capability . Very important and intresting is that redundancy built in . Should any part fail at any point of operation another module automatically kicks in.If CIP module that is actimg as the radio or Radar die/hang up one of the other modules will automatically reload the program and take over radio …etc and finally raptor was fully simulated before even the “hard” mock up of F-22!!!!!!! Sounds fascinating doesn’t it ?
What does all these mean?
Well in laymans terms there is nothing called a “Ablity to track 5 and engage 1…etc” in Raptor , the radar does not have anything called a LOCK and Track , in other words Raptor builds up a Shoot list of all Targets in the viscinity and priortes in a order and gives it to the pilot and the pilot can fire the missile and the bandit will never hear the warning “warning Radar lock” and the when Aim-120 with a terminal seeker head of about 10 miles Turns on only then the pilot will get the warning “INCOMMING Missile” or silly sounds like “BEEP ,BEEEEEEEEEEEEEEP ….etc” in Russians jet and the MIG pilot will have approx~10 seconds to respond to a Aim on his tail ? sounds frightening doesn’t it well Russians will wet their pants if they ever go against the Raptor but this does not end here [ tooooo bad BC] ,
What if a RWR finds the raptor radar ? will raptor not lose its Stealth?
Well partially right ? in EMCON 5 Raptor is not stealthy but then AIM can be fired from EMCON 3 mode also note that the power emitted is not in MW range but in Watts range which means a conventional DTH broadcast has more power than a Raptors Radar , not to forget ground clutter , satellite phones [ ex Thruya L band phones ]………etc is in the same spectrum and unlike other Radars Raptor is not confined to a single frequency of operation , it can occupy [ because of Frequency hopping ] any MW band [ yes from L to upper Ka] in PN sequence order thus the RWR will never notice the faint residual trace and will neglet it back ground noise not only that the RWR does not Know where to Scan in the first place because of no fixed freq band [ ex AIM-120- I band , Adder-J band , Phalcon-Phased array L band conformal Radar-yes L band , N001- Ka or Ku band,E-3,A-50-X band-----nothing like this here ] , thus can never say this is a Raptor also note that RWR are passive devices , ie they listen and dedect by using simple vectoring schemes [ very big math calculation but then what are computers for?] and here lies the problem the computer predicts by extrapolating the vector co-ordinates in 3 D space which is never really accurate in the first place thus the comp correlates the info from RWR with its own radar info + IRST [ if available] but then with the raptor there are two probs
-----The radar beam is not intense and do not use the same freq for more than a micro sec and you need computers which can process in pico secs for this [ ruskies are no where near this, so are anybody] to crack codes.
------The plane radar cannot track the raptor
so what happens , the pilot knows something is out there [ yep dedected] but where? Good question right ? so pilot is faced with two options 1] Eject before raptor Kills him and say mech failure or
2] Pray and wait till a AIM slams on him
Either way GAME OVER
Again it does not end here Raptor radar is impossible to Jam , impossible to dedect , impossible to copy or duplicate like ConcodeSki , Space Shuttle Ski, AMRAAMski …….etc [ I really pity you guys really , Americans are 20 years advanced in Avionics and KGP is dissolved so they could not pass blue prints]
Quote:
Your theory of jamming is prone to hold water
Well ,Well I decided to say exactly why a AESA radar cannot be Jammed
Jamming
Spread spectrum modulation have several advantages when compared with conventional systems . A properly designed Spread spectrum system can operate reliably in various types of RFI [ radio frequency interference] including multi path interference , multiple access interference and hostile jamming .In addition the signal is spread over a wide large bandwith , thus the average power in any slot is low .At any rate the density of Spread spectrum signal is far less than that of conventional signals . this means Spread spectrum systems can share a frequency band with several narrow band signals by NB equipment, thus it very difficult to detect a Spread spectrum signal even by using a NB equipment
Process gain and Jam margin:
The properties of Spread spectrum are characterized by two parameters
------process gain
------Jam margin
in general
process gain=[bandwith of t’xd Spread spectrum signal]/ data rate in base band channel
It is a well known fact that comm. System operates with a required prob of error, if the ratio of energy per bit to the spectral density of interference exceeds some threshold value , the received signal power is product of energy per bit and bit rate so
Pi[watts]=No[watts/Hz]*Wss[Hz]
Thus at the input of the receiver , the signal interference power ratio is
SIR=Pr/Pi=Eb*R/No*Wss
But in spread spectrum signal Wss is much greater Than R and so Eb/No could be in acceptable range [~10] even when SIR is small . foe ex if Eb/No=10 and Wss/R=1000 ,SIR=.01 or -20 dB .Thus Wss/R is called as process gain of the system .It is possible for a spread spectrum receiver even when its input is buried in noise.From the above ex it is clear that even if [Wss/r]/[Eb/No]=100 interferences present at the same band in same time receiver could still operate.
Jamming Margin:
It expresses the capability to perform in hostile environment .Jm takes into account requirement for a useful system output signal to noise ratio and allows for internal losses
J/S and Antijam margin:
The ratio of [J/s] is a figure of merit that provides a mesure of how invulnerable a system is to interference .The larger the [J/S] ,the greater is the systems is to interference but forces to employ a greater processing gain thus used only in AESA.
Anti jam margin:[ j/s] required-[j/s] , in other words one must jam the entire MW spectrum to jam SS signals.
Finally Raptor employs FH-SS tech [ Frequency hopped SS]
Here is comparision graphs [ courtesy IEEE ]
[ please wait till I sort out the link problem , because I am back in India and there is no wireless BB here so I cannot directly use my Laptop , I have to my companies wired connection so give me a day , till then directly use the link http://www.villagephotos.com/pubgallery.asp?id_=491426 ]
Stealth:
Quote:
s-37 is a stealthy aircraft
Well you guys do not know what the hell is stealth means , first how far a radar can track an object depend on its T’xr power , antenna size , receiver sensitivity and finally the RCS of a Target, at first glance sensor designers seen to have an insurmountable advantage in the game of hide and seek .They control most variables can worry less about space requirements and have a dedection that varies as a fourth root of RCS , so halve the dedection range RCS must be slashed to factor of 16 . If Radar echo of a fighter fying head on is reduced from 5 m2 to 0.5 m2 all other things being equal range is cut by 44 percent , but by using higher radar power like those of AWACS , highy increasing signal processing capacity by using DSP and by ability to gather fainter echos and employing MTI indicators to differentiate between stealth aircraft and from slower blips of birds and insect swarms may offer some resistance to stealth but these all are available only in the AESA radar and only US has it [ toooo bad]
Now lets see what contributes to stealth or lack of stealth and there is two kinds of RCS availably [ yep 2 ] which are
1] Frontal RCS ; which in general can be reduced by using delta wings and blending them into fuselage and removing the tail [ which is not possible of course because the jet will be prone to Departures and also the maneuverability reduces drastically ] thus use a slopped tail like F-117 , F-22 ,JSF ……..etc and there is nothing more one can do to reduce except of course using Active Cancellors
2]Back scatter from ground radars : yep this is more tricky to avoid for this the inlet must be placed in the upper side of body and tailfin stabilizers be canted inwards . weapons must be internally carried [ as I said Raptor has 8 internal hardpoints 6 in the middle and two on eithey wings with a combo 6 c + 2 9x / 4 R+2 9x / 4C +1 R +2 9x / 2c +2 fuel tank+2 9x and totally it has including external 13 hardpoints ] , covering the objects with radar absorbing material , replacing metallic ports with resistive or composite structures and using honey combed in key arrays to trap incoming waves are all required [ quite a lot yes but then can we expect from US anything less than this ? guess not ]
and Raptor killer , this is by far the biggest joke I heared and no BS about MCA Lca took 20 years of devepment and still no sign and by going at this pace will only be operational by 2012 , thus the MCA is it fly’s going by these guys will come only near 2025 by which USA will be operating unmanned fighters and yes Pak-Fa is not expected to even fly by 2012 [ and this is supposed to counter the JSF and not the Raptor ] so expect the Raptor to wet the pants of its adversaries in the decades to come just like its daddy the EAGLE did a till now and with AESA and upgrades is still feared by pilots around the world [ speaks fathoms about US tech [ eagle ] what are the odds of a jet developed in 1970’s still reign supreme ? well the Eagle is named as the EAGLE FOR nothing isn’t it ?
[ and Ruskies might spent at the maximum $3 billion on the project [ PAK-FA] , even raptors Radar development would have cost more , poor pathetic beggers I really feel sorry for them but then they should have realized that before competing with the US , no one can compete with U.S.A and yes French + Germen’s pathetic idiots who so pathetic that they know that they cannot compete with the US independently that they form EU ,float a silly currency called the EURO and now are blaming each others for the pathetic state of their economy and inflation+recession and in general misery , oh yes chinease and their dream of becoming a Super Power how the Hell are they going to become Super power when all their exports go to US and their economy is completely controlled by US companies and adding misery to their problem their Currency has no purchasing outside China and now INDIA wants to be a superpower by 2020 ? when will people know better than trying to compete with USA ? it is country filled with resources and huge untapped natural reserves with an industrial might that one cannot even imagine .]
Quote:
How raptor is more equiped to escape from a missile
Before this lets see a Radar detecting and tracking and firing a missile on this , here I am assuming that Raptor is firing at a Fc-1[ ie no interference from EW pods / no evasive maneuvers until final end ] in my next post we shall see a simulation of what happens when all these are present , the radar modeled is based on the characteristics of the F-16 b5 radar and the aerodynamics of the gravity aided AIM-120 A missile [ let me keep the comparison of gravity aided Ram jet missiles like AIM-120 and free running [ utter waste of KE ] missiles like Adder [ has its advantages but ]in other post with simulation comparison of both missiles in o/p graphs. First I would like to thank IEEE journals /my univ prof,s/Matlab/ resource lab and other numerous tools where it actually appeared and my prof who simulated this I am just doing a CCP from their work [ still very complex to work with]
The below dig is a tracker simulator of the radar , note that any radar can be estimated with this , but because of f-16 b5 is known we are using this [ radar with continuos illumination to fire AIM]
Note how the radar generates noise to cancel the input noise
Next step is to estimate the position also by using the Kalman filters
Now the estimates the approx direction by calcu lets now compare it the actual path
now finally the precise co-ordinate by vectors , here again , we have actual and estimated direction
Last but not the least to estimate the residual for range
The computers does an average of all these readings and displays it , note that how close that the results are for a jet without ECM and a RCS of 3m2 but then this is incapable of tracking a RCS of .01 [ bird] so we shall see how well it stands up to an RCS of 1m2 and a less than average ECM introducing a SNR of about .1 db in next post [ sorry do not enogh info to simulate any other radar ]
Now we are going for the action , yep fire a radar guided AAM , as previously said many people were kind enough to model a Gravity guided Aim-120 A for me , so a raptor fires a missile , first we shall see a BD of any radar guided AAM 3-axis guidance [ missile is assumed to be fired from in the simulation from a distance of 9nm~16 kms and the source is moving in a speed of ~500 missiles with a ~2000 feet elevation than the Target so that missile has enough KE to manuvere ]
Now for the target tracker and sightline rate estimator [ seeker in other word]
Now for the guidance part [ I know Aim-120 a uses only a 30 mhz processor but then missile always misses so used a 100 mhz processor like used in 120 R]
Finally the airframe dynamics [ modeled after the 120 A]
Gimbals angles and mode changes [ in other words catching up – go get the assole—yippy],note that the altitude is in negative [ ie the AIM uses gravity to streak down to the target this is why AIM is effective only when fired from a altitude Higher than a targets Altitude , also see how gimbal catches with the true look angles and the mode changes are 1] blind charge 2] correction updates from home 3] turning on ARH 4] Fuse ]
Finally Accelaration , mach nos and other stuff [ note how the dual thrust profile slows the missile while Fins correct and incidence changes and missile experiences a tremendous change in G all in REAL Time [ in woking environment] as seen by the graphs , this is where the processing power of the on-board computer is crucial , a second lag ---all over ]----This graphs if you had noticed is for the ARH phase of the missile--------go get the sucker.
In the real simulation one can see the AAM streaking towards the target but there is no way I can upload it in a webpage ,[ got bored explanation on these in my next post with more missiles in addition to FBW and other stuff]
And how did I forget to say this guess what is the most crucial thing in warfare? GUIDANCE and what does MKI ,AGNI,BHRAMOS,MIG-29…………etc use for guidance ? answer GPS any Bloody military adventure requires GPS guidance which is controlled by US and what if we do not want you guys to fight with Pakistan ? simple deny the use of GPS easy does it , and exactly for this purpose we have three GPS systems
1] normal/civilian or just GPS
2] GPS-II
3]GPS-III which cannot be jammed
The first two can be jammed and is what INDIA use so do the Russians because more than half of GLONASS is not functional and is in such a disarray that even Ruskies use GPS and US uses GPS-III which is reseved for only usa and ISRAEL , thus at any point of time US can JAM GPS and GPS-II at the same time not harming its own interests and denying the enemy the benefits of using GPS , thus usa can influence warfare anywhere just by denying the use of GPS[ Oh I love the US ,they know how to fight by using Brains , what do you guys say ?]
Well in laymans terms there is nothing called a “Ablity to track 5 and engage 1…etc” in Raptor , the radar does not have anything called a LOCK and Track , in other words Raptor builds up a Shoot list of all Targets in the viscinity and priortes in a order and gives it to the pilot and the pilot can fire the missile and the bandit will never hear the warning “warning Radar lock” and the when Aim-120 with a terminal seeker head of about 10 miles Turns on only then the pilot will get the warning “INCOMMING Missile” or silly sounds like “BEEP ,BEEEEEEEEEEEEEEP ….etc” in Russians jet and the MIG pilot will have approx~10 seconds to respond to a Aim on his tail ? sounds frightening doesn’t it well Russians will wet their pants if they ever go against the Raptor but this does not end here [ tooooo bad BC] ,
What if a RWR finds the raptor radar ? will raptor not lose its Stealth?
Well partially right ? in EMCON 5 Raptor is not stealthy but then AIM can be fired from EMCON 3 mode also note that the power emitted is not in MW range but in Watts range which means a conventional DTH broadcast has more power than a Raptors Radar , not to forget ground clutter , satellite phones [ ex Thruya L band phones ]………etc is in the same spectrum and unlike other Radars Raptor is not confined to a single frequency of operation , it can occupy [ because of Frequency hopping ] any MW band [ yes from L to upper Ka] in PN sequence order thus the RWR will never notice the faint residual trace and will neglet it back ground noise not only that the RWR does not Know where to Scan in the first place because of no fixed freq band [ ex AIM-120- I band , Adder-J band , Phalcon-Phased array L band conformal Radar-yes L band , N001- Ka or Ku band,E-3,A-50-X band-----nothing like this here ] , thus can never say this is a Raptor also note that RWR are passive devices , ie they listen and dedect by using simple vectoring schemes [ very big math calculation but then what are computers for?] and here lies the problem the computer predicts by extrapolating the vector co-ordinates in 3 D space which is never really accurate in the first place thus the comp correlates the info from RWR with its own radar info + IRST [ if available] but then with the raptor there are two probs
-----The radar beam is not intense and do not use the same freq for more than a micro sec and you need computers which can process in pico secs for this [ ruskies are no where near this, so are anybody] to crack codes.
------The plane radar cannot track the raptor
so what happens , the pilot knows something is out there [ yep dedected] but where? Good question right ? so pilot is faced with two options 1] Eject before raptor Kills him and say mech failure or
2] Pray and wait till a AIM slams on him
Either way GAME OVER
Again it does not end here Raptor radar is impossible to Jam , impossible to dedect , impossible to copy or duplicate like ConcodeSki , Space Shuttle Ski, AMRAAMski …….etc [ I really pity you guys really , Americans are 20 years advanced in Avionics and KGP is dissolved so they could not pass blue prints]
Quote:
Your theory of jamming is prone to hold water
Well ,Well I decided to say exactly why a AESA radar cannot be Jammed
Jamming
Spread spectrum modulation have several advantages when compared with conventional systems . A properly designed Spread spectrum system can operate reliably in various types of RFI [ radio frequency interference] including multi path interference , multiple access interference and hostile jamming .In addition the signal is spread over a wide large bandwith , thus the average power in any slot is low .At any rate the density of Spread spectrum signal is far less than that of conventional signals . this means Spread spectrum systems can share a frequency band with several narrow band signals by NB equipment, thus it very difficult to detect a Spread spectrum signal even by using a NB equipment
Process gain and Jam margin:
The properties of Spread spectrum are characterized by two parameters
------process gain
------Jam margin
in general
process gain=[bandwith of t’xd Spread spectrum signal]/ data rate in base band channel
It is a well known fact that comm. System operates with a required prob of error, if the ratio of energy per bit to the spectral density of interference exceeds some threshold value , the received signal power is product of energy per bit and bit rate so
Pi[watts]=No[watts/Hz]*Wss[Hz]
Thus at the input of the receiver , the signal interference power ratio is
SIR=Pr/Pi=Eb*R/No*Wss
But in spread spectrum signal Wss is much greater Than R and so Eb/No could be in acceptable range [~10] even when SIR is small . foe ex if Eb/No=10 and Wss/R=1000 ,SIR=.01 or -20 dB .Thus Wss/R is called as process gain of the system .It is possible for a spread spectrum receiver even when its input is buried in noise.From the above ex it is clear that even if [Wss/r]/[Eb/No]=100 interferences present at the same band in same time receiver could still operate.
Jamming Margin:
It expresses the capability to perform in hostile environment .Jm takes into account requirement for a useful system output signal to noise ratio and allows for internal losses
J/S and Antijam margin:
The ratio of [J/s] is a figure of merit that provides a mesure of how invulnerable a system is to interference .The larger the [J/S] ,the greater is the systems is to interference but forces to employ a greater processing gain thus used only in AESA.
Anti jam margin:[ j/s] required-[j/s] , in other words one must jam the entire MW spectrum to jam SS signals.
Finally Raptor employs FH-SS tech [ Frequency hopped SS]
Here is comparision graphs [ courtesy IEEE ]
[ please wait till I sort out the link problem , because I am back in India and there is no wireless BB here so I cannot directly use my Laptop , I have to my companies wired connection so give me a day , till then directly use the link http://www.villagephotos.com/pubgallery.asp?id_=491426 ]
Stealth:
Quote:
s-37 is a stealthy aircraft
Well you guys do not know what the hell is stealth means , first how far a radar can track an object depend on its T’xr power , antenna size , receiver sensitivity and finally the RCS of a Target, at first glance sensor designers seen to have an insurmountable advantage in the game of hide and seek .They control most variables can worry less about space requirements and have a dedection that varies as a fourth root of RCS , so halve the dedection range RCS must be slashed to factor of 16 . If Radar echo of a fighter fying head on is reduced from 5 m2 to 0.5 m2 all other things being equal range is cut by 44 percent , but by using higher radar power like those of AWACS , highy increasing signal processing capacity by using DSP and by ability to gather fainter echos and employing MTI indicators to differentiate between stealth aircraft and from slower blips of birds and insect swarms may offer some resistance to stealth but these all are available only in the AESA radar and only US has it [ toooo bad]
Now lets see what contributes to stealth or lack of stealth and there is two kinds of RCS availably [ yep 2 ] which are
1] Frontal RCS ; which in general can be reduced by using delta wings and blending them into fuselage and removing the tail [ which is not possible of course because the jet will be prone to Departures and also the maneuverability reduces drastically ] thus use a slopped tail like F-117 , F-22 ,JSF ……..etc and there is nothing more one can do to reduce except of course using Active Cancellors
2]Back scatter from ground radars : yep this is more tricky to avoid for this the inlet must be placed in the upper side of body and tailfin stabilizers be canted inwards . weapons must be internally carried [ as I said Raptor has 8 internal hardpoints 6 in the middle and two on eithey wings with a combo 6 c + 2 9x / 4 R+2 9x / 4C +1 R +2 9x / 2c +2 fuel tank+2 9x and totally it has including external 13 hardpoints ] , covering the objects with radar absorbing material , replacing metallic ports with resistive or composite structures and using honey combed in key arrays to trap incoming waves are all required [ quite a lot yes but then can we expect from US anything less than this ? guess not ]
and Raptor killer , this is by far the biggest joke I heared and no BS about MCA Lca took 20 years of devepment and still no sign and by going at this pace will only be operational by 2012 , thus the MCA is it fly’s going by these guys will come only near 2025 by which USA will be operating unmanned fighters and yes Pak-Fa is not expected to even fly by 2012 [ and this is supposed to counter the JSF and not the Raptor ] so expect the Raptor to wet the pants of its adversaries in the decades to come just like its daddy the EAGLE did a till now and with AESA and upgrades is still feared by pilots around the world [ speaks fathoms about US tech [ eagle ] what are the odds of a jet developed in 1970’s still reign supreme ? well the Eagle is named as the EAGLE FOR nothing isn’t it ?
[ and Ruskies might spent at the maximum $3 billion on the project [ PAK-FA] , even raptors Radar development would have cost more , poor pathetic beggers I really feel sorry for them but then they should have realized that before competing with the US , no one can compete with U.S.A and yes French + Germen’s pathetic idiots who so pathetic that they know that they cannot compete with the US independently that they form EU ,float a silly currency called the EURO and now are blaming each others for the pathetic state of their economy and inflation+recession and in general misery , oh yes chinease and their dream of becoming a Super Power how the Hell are they going to become Super power when all their exports go to US and their economy is completely controlled by US companies and adding misery to their problem their Currency has no purchasing outside China and now INDIA wants to be a superpower by 2020 ? when will people know better than trying to compete with USA ? it is country filled with resources and huge untapped natural reserves with an industrial might that one cannot even imagine .]
Quote:
How raptor is more equiped to escape from a missile
Before this lets see a Radar detecting and tracking and firing a missile on this , here I am assuming that Raptor is firing at a Fc-1[ ie no interference from EW pods / no evasive maneuvers until final end ] in my next post we shall see a simulation of what happens when all these are present , the radar modeled is based on the characteristics of the F-16 b5 radar and the aerodynamics of the gravity aided AIM-120 A missile [ let me keep the comparison of gravity aided Ram jet missiles like AIM-120 and free running [ utter waste of KE ] missiles like Adder [ has its advantages but ]in other post with simulation comparison of both missiles in o/p graphs. First I would like to thank IEEE journals /my univ prof,s/Matlab/ resource lab and other numerous tools where it actually appeared and my prof who simulated this I am just doing a CCP from their work [ still very complex to work with]
The below dig is a tracker simulator of the radar , note that any radar can be estimated with this , but because of f-16 b5 is known we are using this [ radar with continuos illumination to fire AIM]
Note how the radar generates noise to cancel the input noise
Next step is to estimate the position also by using the Kalman filters
Now the estimates the approx direction by calcu lets now compare it the actual path
now finally the precise co-ordinate by vectors , here again , we have actual and estimated direction
Last but not the least to estimate the residual for range
The computers does an average of all these readings and displays it , note that how close that the results are for a jet without ECM and a RCS of 3m2 but then this is incapable of tracking a RCS of .01 [ bird] so we shall see how well it stands up to an RCS of 1m2 and a less than average ECM introducing a SNR of about .1 db in next post [ sorry do not enogh info to simulate any other radar ]
Now we are going for the action , yep fire a radar guided AAM , as previously said many people were kind enough to model a Gravity guided Aim-120 A for me , so a raptor fires a missile , first we shall see a BD of any radar guided AAM 3-axis guidance [ missile is assumed to be fired from in the simulation from a distance of 9nm~16 kms and the source is moving in a speed of ~500 missiles with a ~2000 feet elevation than the Target so that missile has enough KE to manuvere ]
Now for the target tracker and sightline rate estimator [ seeker in other word]
Now for the guidance part [ I know Aim-120 a uses only a 30 mhz processor but then missile always misses so used a 100 mhz processor like used in 120 R]
Finally the airframe dynamics [ modeled after the 120 A]
Gimbals angles and mode changes [ in other words catching up – go get the assole—yippy],note that the altitude is in negative [ ie the AIM uses gravity to streak down to the target this is why AIM is effective only when fired from a altitude Higher than a targets Altitude , also see how gimbal catches with the true look angles and the mode changes are 1] blind charge 2] correction updates from home 3] turning on ARH 4] Fuse ]
Finally Accelaration , mach nos and other stuff [ note how the dual thrust profile slows the missile while Fins correct and incidence changes and missile experiences a tremendous change in G all in REAL Time [ in woking environment] as seen by the graphs , this is where the processing power of the on-board computer is crucial , a second lag ---all over ]----This graphs if you had noticed is for the ARH phase of the missile--------go get the sucker.
In the real simulation one can see the AAM streaking towards the target but there is no way I can upload it in a webpage ,[ got bored explanation on these in my next post with more missiles in addition to FBW and other stuff]
And how did I forget to say this guess what is the most crucial thing in warfare? GUIDANCE and what does MKI ,AGNI,BHRAMOS,MIG-29…………etc use for guidance ? answer GPS any Bloody military adventure requires GPS guidance which is controlled by US and what if we do not want you guys to fight with Pakistan ? simple deny the use of GPS easy does it , and exactly for this purpose we have three GPS systems
1] normal/civilian or just GPS
2] GPS-II
3]GPS-III which cannot be jammed
The first two can be jammed and is what INDIA use so do the Russians because more than half of GLONASS is not functional and is in such a disarray that even Ruskies use GPS and US uses GPS-III which is reseved for only usa and ISRAEL , thus at any point of time US can JAM GPS and GPS-II at the same time not harming its own interests and denying the enemy the benefits of using GPS , thus usa can influence warfare anywhere just by denying the use of GPS[ Oh I love the US ,they know how to fight by using Brains , what do you guys say ?]
看不到图……
哇~~哇~哇~哇~~~~~头大,看不懂啊!!!
看不懂
惭愧！！偶下定决心要去恶补一下英国驴屎！！
１ 等离子隐身ー＞阿三意淫老毛子的理論。老毛子成功了再教給他巴。
２ 主动电子信号抵消器ー＞小学生都知道正波＋負波＝０、説得容易。真要達到”使得敌方雷达更本收不到信号”之水平的話、美国還玩命研究”几何隐身”和”隐身涂料”干什么？自円其説都不会。
３ 美国的AMRAM 120导弹的借助地球重力加速ー＞F14上的不死鳥就是这様了、阿三現在才知道、真SB。所謂”借助地球重力加速”、説白了就是前段飛行時向斜上方飛、後段向斜下方飛、这様利用前段時蓄積的勢能化為後段的動能、提高末段速度。就好象縦高処往下滑自行車一様、没一点了不起的地方。
４ F22的雷达信号处理器功能强大...........使得F22几乎没有跟踪扫描敌方飞机数量的限制->阿三的意淫論：超級計算機＋相控阵雷达 ＝戦闘力無限大。就算F22可以跟踪扫描無数的敌方飞机、他的載弾量可是有限的。TWS超過３０以上、或交戦数超過１０以上、実際没有太大意義。
総之、阿三不先把自称無敵的”阿窮”和超越F22的”LCA”造得象様一点的話、越吹越顕得象個小醜。
２ 主动电子信号抵消器ー＞小学生都知道正波＋負波＝０、説得容易。真要達到”使得敌方雷达更本收不到信号”之水平的話、美国還玩命研究”几何隐身”和”隐身涂料”干什么？自円其説都不会。
３ 美国的AMRAM 120导弹的借助地球重力加速ー＞F14上的不死鳥就是这様了、阿三現在才知道、真SB。所謂”借助地球重力加速”、説白了就是前段飛行時向斜上方飛、後段向斜下方飛、这様利用前段時蓄積的勢能化為後段的動能、提高末段速度。就好象縦高処往下滑自行車一様、没一点了不起的地方。
４ F22的雷达信号处理器功能强大...........使得F22几乎没有跟踪扫描敌方飞机数量的限制->阿三的意淫論：超級計算機＋相控阵雷达 ＝戦闘力無限大。就算F22可以跟踪扫描無数的敌方飞机、他的載弾量可是有限的。TWS超過３０以上、或交戦数超過１０以上、実際没有太大意義。
総之、阿三不先把自称無敵的”阿窮”和超越F22的”LCA”造得象様一点的話、越吹越顕得象個小醜。
以下是引用gun在2003-11-19 14:33:00的发言：
１ 等离子隐身ー＞阿三意淫老毛子的理論。老毛子成功了再教給他巴。
２ 主动电子信号抵消器ー＞小学生都知道正波＋負波＝０、説得容易。真要達到”使得敌方雷达更本收不到信号”之水平的話、美国還玩命研究”几何隐身”和”隐身涂料”干什么？自円其説都不会。
３ 美国的AMRAM 120导弹的借助地球重力加速ー＞F14上的不死鳥就是这様了、阿三現在才知道、真SB。所謂”借助地球重力加速”、説白了就是前段飛行時向斜上方飛、後段向斜下方飛、这様利用前段時蓄積的勢能化為後段的動能、提高末段速度。就好象縦高処往下滑自行車一様、没一点了不起的地方。
４ F22的雷达信号处理器功能强大...........使得F22几乎没有跟踪扫描敌方飞机数量的限制->阿三的意淫論：超級計算機＋相控阵雷达 ＝戦闘力無限大。就算F22可以跟踪扫描無数的敌方飞机、他的載弾量可是有限的。TWS超過３０以上、或交戦数超過１０以上、実際没有太大意義。
総之、阿三不先把自称無敵的”阿窮”和超越F22的”LCA”造得象様一点的話、越吹越顕得象個小醜。
[em09][em09]
英语水平太差哒
ding
他的一些曲线图好像使用matlab做的，呵呵
看得懂,懒得看.此阿三的盲目崇洋精神,应向整个印度推广!
他的MATLAB不错，向他学习，其他的就不说什么了。
""F22采用了将近5种隐身科技，有：
1。 几何隐身 - 通过飞机外形结构散射雷达信号。
2。 等离子隐身 - 通过由飞机前机翼释放出的电离层来改变飞机的雷达反射特征。
3。 隐身涂料 - 飞机外涂有电子信号吸收材料，已降低反射率。
4。 主动电子信号抵消器 - 飞机能够在受到敌方雷达信号的同时制造出与自身反射波相抵消的主动雷达信号，反射波抵消使得敌方雷达更本收不到信号。
5。 延频，跳频主动相控阵雷达 - 己方雷达即便开机对方的被动雷达信号侦测器也感收不到，感收的到也跟踪不了，跟踪的了也无法及时计算位置。""
只有第5条:"5。 延频，跳频主动相控阵雷达 - 己方雷达即便开机对方的被动雷达信号侦测器也感收不到，感收的到也跟踪不了，跟踪的了也无法及时计算位置。"阿三说的还不错----<<兵器>>2003.12期有介绍.
1。 几何隐身 - 通过飞机外形结构散射雷达信号。
2。 等离子隐身 - 通过由飞机前机翼释放出的电离层来改变飞机的雷达反射特征。
3。 隐身涂料 - 飞机外涂有电子信号吸收材料，已降低反射率。
4。 主动电子信号抵消器 - 飞机能够在受到敌方雷达信号的同时制造出与自身反射波相抵消的主动雷达信号，反射波抵消使得敌方雷达更本收不到信号。
5。 延频，跳频主动相控阵雷达 - 己方雷达即便开机对方的被动雷达信号侦测器也感收不到，感收的到也跟踪不了，跟踪的了也无法及时计算位置。""
只有第5条:"5。 延频，跳频主动相控阵雷达 - 己方雷达即便开机对方的被动雷达信号侦测器也感收不到，感收的到也跟踪不了，跟踪的了也无法及时计算位置。"阿三说的还不错----<<兵器>>2003.12期有介绍.