Research on BDSBAS Dual-Frequency Message Scheduler Optimization

By analyzing the broadcasting status of the BDSBAS-B2a message, it is found that there are some problems in its current strategy, such as low proportion of effective messages, poor flexibility, poor standard compliance and poor scalability. Based on this, this paper puts forward a dynamic scheduling strategy of dual-frequency message with fixed time sequence, which makes full use of dual-frequency ranging error change identifier (DFRECI) to represent the change of dual-frequency ranging error identifier (DFREI). At the same time, this paper simulated the broadcast of the strategy. The result shows that when the strategy enhances three basic constellations under the normal operation of BDSBAS, the proportion of effective messages can reach 100%. Compared with current arrangement, the time for users to receive all types of messages for the first time is shortened by 41.67%. By making effective use of MT34, the strategy can increase the number of enhanced satellites from the current 54 to 85, which greatly improves the problem of poor scalability of enhanced satellites caused by overseas stations and the increase of constellations in the future.