China News Service, Beijing, December 1. According to news from the China National Space Administration’s Lunar Exploration and Space Engineering Center on the 1st, in November, China’s “Tianwen 1” and the ESA’s “Mars Express” mission team carried out the “Zhu Rong” mission. The on-orbit relay communication test between the Mars rover and the Mars Express orbiter was a complete success.
Before the test, the respective detectors in both directions must be instructed to make preparations for the test.
At the appointed time, the "Zhurong" will send the test data to the "Mars Express", the communication distance is about 4000 kilometers, and the communication time is 10 minutes.
"Mars Express" receives the data and forwards it to the deep space monitoring and control station subordinate to ESA. After receiving the data, the monitoring and control station sends it to the European Space Operations Center (ESOC). The ESOC is then forwarded to the Beijing Aerospace Flight Control Center. After interpretation by the Chinese technical team, Interpret the correctness of the data.
According to the results of data interpretation and analysis, the mission teams of both parties confirmed that the relay communication device interfaces of the "Zhurong" and "Mars Express" match, conform to international standards, and the content of the transmitted data is complete and correct, and the test is a success.
In the future, the two parties will further develop scientific data relay communication cooperation on the basis of this phase of experimentation.
According to reports, due to weight and volume constraints, the Mars rover has weak direct-to-ground communication capabilities and cannot meet the demand for large amounts of data transmission. Therefore, it is necessary to send the data to the Mars orbiter that is closer, and it is forwarded to the orbiter with stronger communication capability. In the ground receiving system, this process is called relay communication.
Under normal circumstances, before establishing relay communication, the orbiter will first send an "initiation" signal to the rover, and the rover will reply with an "confirmation" signal, and then the two parties will establish a stable two-way relay communication link, just like a friend making a call You need to make a phone call first.
Since the launch frequency of the "Mars Express" does not match the receiving frequency of the "Zhurong", the communication link cannot be established by "dialing the phone".
The transmitting frequency of "Zhurong" matches the receiving frequency of "Mars Express", so the two parties need to agree on the communication time in advance, and "Zhurong" will send data directly, and "Mars Express" will conduct "blind reception".
The "Mars Express" orbiter has a "blind harvest" function, but there has been no opportunity to actually use this function for more than a decade.
ESA stated that this test is a good opportunity for the "Mars Express" to verify the "blind harvest" model in orbit.
It is reported that the "Zhu Rong" rover currently works on the surface of Mars for 196 Mars days, has traveled 1,297 meters in total, obtained about 10GB of raw scientific data for inspections, and has sufficient energy and good condition.