Research on Positioning Method in the Lunar Space

With the accomplish of Chang’e-5 mission, China’s Chang’e mission has entered the next stage, that is, the development and utilization of the moon and the construction of the lunar station. However, in this stage of lunar surface exploration mission, the accuracy of positioning cannot meet the requirement. In the paper, we provide the telemetry, tracking, command (TT&C) and communication links in the lunar space at the lunar station. Then, the high accuracy positioning method is given. The method mainly positioning by ranging and angle measurement. The ranging completes the acquisition of radial parameters of transceiver nodes, and the angle measurement acquire the tangential parameters. In order to obtain high precision positioning results, BOC (5, 1) modulation system and dual one-way ranging (DOWR) are used to measure the distance, and L-type interferometer is used to measure the angle. Besides, we design the angle measurement algorithm to increase the number of transmitter that can be measured by the interferometer. Under the condition of carrier to noise ratio of 60 dBHz, the ranging accuracy is 0.947 ns, and the angle measurement accuracy is higher than 0.02 rad.