火星探测UHF频段原位通信关键技术研究

火星是人类探索太阳系的下一个里程碑，由于地球和火星之间的距离非常遥远（最远距离约4亿千米，光行时约22min），为了最大限度地完成火星车和地球之间的高效通信，火星车和火星环绕器之间的器间原位中继通信技术就显得尤为重要。针对大椭圆轨道下器间通信信噪比低、信号参数变化快、全自主要求高及质量功耗约束极为严苛等难点，提出了一种UHF频段器间原位通信技术，主要包括超高灵敏度高动态自适应信号解调、高精度多普勒测量、基于CCSDS Proximity-1的协议一体化集成融合和面向火星复杂环境的高集成度高收发隔离产品工程化设计，实现了捕获灵敏度优于-141dBm、解调灵敏度（1kbit/s）优于-134dBm、频率动态范围优于±26kHz、多普勒测量精度优于10mHz、收发隔离大于180dB、弧段内全自主高可靠高吞吐率通信及基于架构统型的系统/单机极限优化，相关指标优于美国系列火星探测器中的“Electra”。经祝融号火星车和天问一号火星环绕器、ESA“Mars Express”火星轨道器在轨实际测试，测试数据符合预期，为中国首次火星探测的圆满成功做出了重要贡献。

Research of UHF band relay communication key techniques for Mars exploration

Mars is the next milestone in our exploration of solar system.Due to the very long distance between the Earth and Mars（the longest distance is about 400 million kilometers，and the light travel time is about 22 minutes），in order to maximize the efficient communication between the Mars rover and the Earth，the inter vehicle relay communication technology between the Mars rover and the Mars Orbiter is particularly important.Aiming at overcoming the difficulties of low signal-to-noise ratio，rapid change of signal parameters，high requirements for full autonomy and extremely strict weight and power constraints of inter device communication in large elliptical orbit，a UHF band relay communication technique was proposed，mainly including ultra-high sensitivity and high dynamic adaptive signal demodulation，high precise Doppler measurement，the CCSDS Proximity-1 multiple dimensional integration and the highly integration and RX/TX isolation engineering design of transceiver product，achieving the acquisition sensitivity better than -141dBm，demodulation sensitivity（1kbit/s）better than -134dBm，frequency dynamic range better than ±26kHz，Doppler measurement precision better than 10mHz，RX/TX isolation greater than 180dB，fully autonomous，high reliability and high throughput communication in the visible arc section and system/product extreme optimization.The relevant performance indexes are better than the "Electra" in the American series of Mars probes.After the actual on orbit tests of the “Zhurong” Mars rover，the “Tianwen-1” Mars orbiter and the ESA “Mars Express” orbiter，the test data met the expectations and made a key contribution to the success of China′s first Mars exploration.