10.4 Design of Telemetry/Telecommand and Telecommunication Technology
357
Fig. 10.13 Pattern of UHF receiving antenna
After the pitch angles of (1) and (2) were considered, the pitch angle covered by
the UHF antenna pattern was determined. The monopole antenna was installed on
the lunar lander for reception of the telemetry exploration data of the lunar rover.
The monopole antenna pattern was fully covered in the horizontal direction, and
the elevation pattern was in “∞” shape, which could satisfy the requirements of
telecommunication between the lunar probes on lunar surface.
4. Telecommunication Model between Lunar Probes
The radio wave in telecommunication between the lunar probes on lunar surface was
transmitted in form of space wave and ground wave. The received signal strength at
the receiver was affected by direct wave, reflected wave, and the scattering effects
of the reflected wave on rough surface.
1) Reflection and scattering models on lunar surface
When the radio wave encountered a smooth reflective surface in the transmission path,
it would be reflected, and scattering occurs when it encountered a rough reflective
surface. According to different roughness of the reflective surface, the reflective
surface could be classified into smooth reflective surface and rough reflective surface.
Electromagnetic wave was reflected on smooth reflective surfaces and scattered on
rough reflective surfaces.
357
Fig. 10.13 Pattern of UHF receiving antenna
After the pitch angles of (1) and (2) were considered, the pitch angle covered by
the UHF antenna pattern was determined. The monopole antenna was installed on
the lunar lander for reception of the telemetry exploration data of the lunar rover.
The monopole antenna pattern was fully covered in the horizontal direction, and
the elevation pattern was in “∞” shape, which could satisfy the requirements of
telecommunication between the lunar probes on lunar surface.
4. Telecommunication Model between Lunar Probes
The radio wave in telecommunication between the lunar probes on lunar surface was
transmitted in form of space wave and ground wave. The received signal strength at
the receiver was affected by direct wave, reflected wave, and the scattering effects
of the reflected wave on rough surface.
1) Reflection and scattering models on lunar surface
When the radio wave encountered a smooth reflective surface in the transmission path,
it would be reflected, and scattering occurs when it encountered a rough reflective
surface. According to different roughness of the reflective surface, the reflective
surface could be classified into smooth reflective surface and rough reflective surface.
Electromagnetic wave was reflected on smooth reflective surfaces and scattered on
rough reflective surfaces.