Modulation performance test method for navigational satellite binary offset carrier signal

Abstract

The invention discloses a modulation performance test method for a navigational satellite binary offset carrier signal. The modulation performance test method comprises the following steps of: firstly, carrying out direct A / D sampling on a BOC (binary offset carrier) modulation navigation signal of a navigational satellite downlink transmission microwave frequency band; then, carrying out variable-frequency filtering and hilbert transform on the signal in a numeric field; carrying out quadrature demodulation, channel gain compensation and phase compensation processing in digital communication, and filtering by a measurement filter to obtain measured data; carrying out symbol detection, reference signal generation processing and reference filtering on the measured data to obtain reference data; and calculating the reference data and the measured data to obtain a parameter and a signal graph which reflects the base band modulation performance. The BOC carrier modulation signal is processed in the numeric field by the modulation performance test method. Because a BOC single sideband frequency spectrum is extracted in the numeric field, the problem that the BOC signal can not be subjected to the modulation characteristic test through a vector signal analysis method because of subcarrier can be solved.

Description

technical field [0001] The invention relates to a method for testing the modulation performance of navigation satellite downlink broadcasting signals. Background technique [0002] At present, my country is developing a new generation of global navigation satellite systems. The difference from the previous generation of regional satellite navigation systems is that in order to improve the accuracy and anti-interference ability of satellite navigation signals, BOC (binary offset) will be added to the signal system of navigation satellites. The baseband modulation performance of the navigation signal is an important aspect of the navigation signal performance. In the satellite development process, the baseband modulation performance parameter of the downlink navigation performance of the navigation satellite is the key parameter in the whole satellite test. [0003] The baseband modulation performance test of the existing digital modulation signal generally adopts the following...

AI Technical Summary

Problems solved by technology

Since BOC is a new type of digital modulation signal, it is mainly used for navigation signals. The parameters of the modulation signal are not only related to the carrier frequency and code rate, but also related to the subcarrier frequency. However, the existing commercial analyzers or vector signal analysis software only For the carrier frequency and code rate, it is impossible to complete the test of all baseband modulation performance parameters of BOC modulated navigation signals

[0004] There are also many literatures on vector signal analysis, but the methods described in these literatures have the following two types of deficiencies: the first type is that the training sequence signal is required to perform channel estimation on the process of signal frequency conversion processing, in order to complete the channel amplitude compensation and The parameter setting of the phase compensation algorithm requires the generation of high-quality training signals

Due to the high modulation quality of the navigation signal, the estimated error will affect the test results, and the channel estimation algorithm is complicated to implement in this method

Images