Assessing Radio Frequency Compatibility Between Galileo and Compass

The radio frequency compatibility between Galileo and Compass has become a matter of great concern for the system providers and user community. This paper mainly deals with the intersystem interference between Galileo and Compass systems and displays some important analysis results. First, a comprehensive methodology for the radio frequency compatibility assessment is described, considering the geometry-dependent and time-varying terms such as space constellation, signal modulation, emission power level, space loss, satellite antenna gain, and user receiver characteristic. Second, real simulations were carried out to assess the interference effects where Galileo and Compass signals were sharing the same band. Simulation results show that Compass introduces intersystem interference to Galileo, but the interference effects are lower than those of Compass interfered to Galileo signals. In addition, the radio frequency compatibility in Asia-Pacific region was analysed. It was found that the maximum interference suffered by Galileo from Compass was below 0.25dB under existing rules of coordination at International Telecommunication Union (ITU). In other words, Compass can provide a sound basis for compatibility with Galileo.