超级军网火星探测信号传输问题
来源：百度文库 编辑：超级军网 时间：2024/04/29 11:52:33
看新闻说火星探测受超远距离信号传输延时和火星自转影响，只能接收到大约5%到10%的数据。为了增加地球对火星的测控时间范围，可否考虑在火星——太阳两个天体的L2点放一颗中继卫星，再在L4或L5点放一颗中继卫星，这样就使得处在火星上背对太阳一面的探测器也能长时间保持与地球的通信，第一次发帖，欢迎拍砖
看新闻说火星探测受超远距离信号传输延时和火星自转影响，只能接收到大约5%到10%的数据。为了增加地球对火星的测控时间范围，可否考虑在火星——太阳两个天体的L2点放一颗中继卫星，再在L4或L5点放一颗中继卫星，这样就使得处在火星上背对太阳一面的探测器也能长时间保持与地球的通信，第一次发帖，欢迎拍砖
小白说一句 信号是会衰竭的
那你这颗卫星要相当大,天线要大,功率也要大......
未来如果要执行登陆火星的时候，可能会有，现在搞不太现实！
以前NASA有个火星通讯卫星MTO项目，采用激光通讯，火星高轨道，基本只用于通讯中继。
后来取消了。因为发现需要中继的还是少，划不来。用低轨道或者椭圆轨道的火星探测器兼职中继便可，虽然中继时间比较受限。
现在在火星兼职进行中继任务的NASA轨道器有两个：奥德赛和MRO，后面要发射的火星科学实验室MSL也要靠这两个进行中继了。
以前NASA有个火星通讯卫星MTO项目，采用激光通讯，火星高轨道，基本只用于通讯中继。
后来取消了。因为发现需要中继的还是少，划不来。用低轨道或者椭圆轨道的火星探测器兼职中继便可，虽然中继时间比较受限。
现在在火星兼职进行中继任务的NASA轨道器有两个：奥德赛和MRO，后面要发射的火星科学实验室MSL也要靠这两个进行中继了。
垂死老头 发表于 2011-11-11 19:17 
小白说一句 信号是会衰竭的
信号中继的另外一个主要作用就是对衰减的信号进行再放大并转发
小白说一句 信号是会衰竭的
信号中继的另外一个主要作用就是对衰减的信号进行再放大并转发
windrarara 发表于 2011-11-11 19:33
那你这颗卫星要相当大,天线要大,功率也要大......
天线大小和功率应该都不是问题吧，因为环火星轨道上的卫星都可以直接同地球通信，只是觉得L2点的卫星能源供应可能是个问题，因为不知道在L2点火星把太阳光挡住了多少
那你这颗卫星要相当大,天线要大,功率也要大......
天线大小和功率应该都不是问题吧，因为环火星轨道上的卫星都可以直接同地球通信，只是觉得L2点的卫星能源供应可能是个问题，因为不知道在L2点火星把太阳光挡住了多少
zzjj123 发表于 2011-11-11 19:38
未来如果要执行登陆火星的时候，可能会有，现在搞不太现实！
这个费用确实要大一点，但在拉格郎日点几乎不消耗卫星燃料，所以这里的卫星寿命可以做得很长，能供长期的火星探测使用，我也觉得以后搞载人登火等大型探测工程可以发射这样的中继卫星
未来如果要执行登陆火星的时候，可能会有，现在搞不太现实！
这个费用确实要大一点，但在拉格郎日点几乎不消耗卫星燃料，所以这里的卫星寿命可以做得很长，能供长期的火星探测使用，我也觉得以后搞载人登火等大型探测工程可以发射这样的中继卫星
lockie 发表于 2011-11-11 20:19
天线大小和功率应该都不是问题吧，因为环火星轨道上的卫星都可以直接同地球通信，只是觉得L2点的卫星能源 ...
环火星轨道上的卫星都可以直接同地球通信。
======================================================
不是的，火星探测器为了近距离观测，一般轨道高度都很低（一些探测器入轨时甚至利用火星上层大气作减速）。这样，绕火星的每圈中，相当长时间里地球位于火星地平线以下，也就无法与地球通联。
而NASA当年开发的MTO火星通讯星采用高轨道，地球几乎很少受到遮挡。而高轨道又能最大限度的扩大中继视野范围。高轨道也不存在轨道保持的问题（不同于同步星）。
至于扩大带宽，MTO采用了专门的激光通讯器，带宽比无线电高至少一个数量级。
MTO由于采用了高轨道，已经不再用于探测任务，没带什么科学设备，设计目标就是专用通讯星。
但后来因为经费等原因取消了，单独为火星搞个通讯星还是太昂贵。
lockie 发表于 2011-11-11 20:19
天线大小和功率应该都不是问题吧，因为环火星轨道上的卫星都可以直接同地球通信，只是觉得L2点的卫星能源 ...
环火星轨道上的卫星都可以直接同地球通信。
======================================================
不是的，火星探测器为了近距离观测，一般轨道高度都很低（一些探测器入轨时甚至利用火星上层大气作减速）。这样，绕火星的每圈中，相当长时间里地球位于火星地平线以下，也就无法与地球通联。
而NASA当年开发的MTO火星通讯星采用高轨道，地球几乎很少受到遮挡。而高轨道又能最大限度的扩大中继视野范围。高轨道也不存在轨道保持的问题（不同于同步星）。
至于扩大带宽，MTO采用了专门的激光通讯器，带宽比无线电高至少一个数量级。
MTO由于采用了高轨道，已经不再用于探测任务，没带什么科学设备，设计目标就是专用通讯星。
但后来因为经费等原因取消了，单独为火星搞个通讯星还是太昂贵。
MTO火星通讯星的资料：
NASA's Mars Telecommunications Orbiter (MTO) will be the first spacecraft to travel to another planet for the primary purpose of relaying communications to and from Earth. In fact, it will serve as a Mars communications hub for a growing interplanetary Internet. Rovers, science stations, and orbiting spacecraft will all communicate with Earth by sending and receiving signals via the Mars Telecommunications Orbiter. The spacecraft will be in contact with Earth almost around the clock, because its orbit will place it 20 times farther from the planet's surface than other spacecraft, meaning it will nearly always have a direct line of sight to Earth. The Mars Telecommunications Orbiter will fly above the surface of Mars at a distance of 5,000 kilometers.
Besides sending and receiving communications at radio and microwave frequencies, the Mars Telecommunications Orbiter will pioneer the use of lasers for planet-to-planet communications. These lasers will transmit and receive signals using near infrared light - just beyond the range of the electromagnetic spectrum seen by the human eye. The signals will travel tens of millions of miles through space. Though optical communications are more susceptible to inteference from clouds, they have the potential to transmit 10,000 times as much data as microwave communications.
During its 10-year mission in orbit, the Mars Telecommunications Orbiter will send the equivalent of three full compact disks of data to Earth each day. These will include data from the Mars Science Laboratory, which will land on Mars about a month after the Mars Telecommunications Orbiter enters orbit around the planet, and deploy a robotic rover to conduct more detailed scientific observations of the martian surface than ever before.
The Mars Telecommunications Orbiter will also carry a sphere the size of a soccer ball and track the device after deploying it in orbit around the Red Planet. This demonstration will support NASA's plan to launch a Mars Sample Return mission in 2013 to collect and bring Mars rocks back to Earth robotically. Successful retrieval of the samples will require an orbiting spacecraft to accurately track and intercept a sample container launched from the martian surface.
Lockheed Martin Space Systems is expected to land a NASA contract to design and build the $500 million Mars Telecommunications Orbiter, which the space agency said will pioneer the use of lasers for planet-to-planet communication. NASA and the Jefferson County-based aerospace company are in negotiations expected to lead to the award of a design-and-construction contract in June 2005. The MTO design will be based largely on the Mars Reconnaissance Orbiter, another NASA spacecraft built at Lockheed Martin's Waterton Canyon facility in Jefferson County.
NASA cancelled the plan to construct MTO in July 2005.
Nation: USA
Type / Application: Mars orbiter
Operator: NASA
Contractors: Lockheed Martin
Equipment:
Configuration:
Propulsion: six 170 N monopropellant engines ?
Power: 2 deployable solar arrays, batteries
Lifetime: 10 years
Mass: 1800 kg
Orbit: Heliocentric, then Mars orbit
NASA's Mars Telecommunications Orbiter (MTO) will be the first spacecraft to travel to another planet for the primary purpose of relaying communications to and from Earth. In fact, it will serve as a Mars communications hub for a growing interplanetary Internet. Rovers, science stations, and orbiting spacecraft will all communicate with Earth by sending and receiving signals via the Mars Telecommunications Orbiter. The spacecraft will be in contact with Earth almost around the clock, because its orbit will place it 20 times farther from the planet's surface than other spacecraft, meaning it will nearly always have a direct line of sight to Earth. The Mars Telecommunications Orbiter will fly above the surface of Mars at a distance of 5,000 kilometers.
Besides sending and receiving communications at radio and microwave frequencies, the Mars Telecommunications Orbiter will pioneer the use of lasers for planet-to-planet communications. These lasers will transmit and receive signals using near infrared light - just beyond the range of the electromagnetic spectrum seen by the human eye. The signals will travel tens of millions of miles through space. Though optical communications are more susceptible to inteference from clouds, they have the potential to transmit 10,000 times as much data as microwave communications.
During its 10-year mission in orbit, the Mars Telecommunications Orbiter will send the equivalent of three full compact disks of data to Earth each day. These will include data from the Mars Science Laboratory, which will land on Mars about a month after the Mars Telecommunications Orbiter enters orbit around the planet, and deploy a robotic rover to conduct more detailed scientific observations of the martian surface than ever before.
The Mars Telecommunications Orbiter will also carry a sphere the size of a soccer ball and track the device after deploying it in orbit around the Red Planet. This demonstration will support NASA's plan to launch a Mars Sample Return mission in 2013 to collect and bring Mars rocks back to Earth robotically. Successful retrieval of the samples will require an orbiting spacecraft to accurately track and intercept a sample container launched from the martian surface.
Lockheed Martin Space Systems is expected to land a NASA contract to design and build the $500 million Mars Telecommunications Orbiter, which the space agency said will pioneer the use of lasers for planet-to-planet communication. NASA and the Jefferson County-based aerospace company are in negotiations expected to lead to the award of a design-and-construction contract in June 2005. The MTO design will be based largely on the Mars Reconnaissance Orbiter, another NASA spacecraft built at Lockheed Martin's Waterton Canyon facility in Jefferson County.
NASA cancelled the plan to construct MTO in July 2005.
Nation: USA
Type / Application: Mars orbiter
Operator: NASA
Contractors: Lockheed Martin
Equipment:
Configuration:
Propulsion: six 170 N monopropellant engines ?
Power: 2 deployable solar arrays, batteries
Lifetime: 10 years
Mass: 1800 kg
Orbit: Heliocentric, then Mars orbit
rolltide 发表于 2011-11-11 21:26
MTO火星通讯星的资料：
NASA's Mars Telecommunications Orbiter (MTO) will be the first spacecraft t ...
学习了。。。。。
MTO火星通讯星的资料：
NASA's Mars Telecommunications Orbiter (MTO) will be the first spacecraft t ...
学习了。。。。。