Capacity Analysis of Burst Spread Spectrum Satellite System

In order to reduce the conflict probability between users of burst spread spectrum satellite system and improve the system capacity, this paper proposes a segment spreading algorithm based on hybrid spreading of long and short codes. The algorithm divides the user's burst information into synchronization segment and information segment, and spreads the synchronization segment composed of link synchronization and frame synchronization with a short code sequence; and spreads the information segment consisting of frame header, data and frame tail with a long code sequence. Compared with the system of spreading the frequency of the whole burst information by using short code or long code alone, this algorithm can not only utilize the good auto-correlation of short code to complete the signal capture, but also utilize the inter-correlation between long code sequences to avoid aggravating the multi-access interference and increase the confidentiality of information. On the basis of ensuring the probability of successful capture of burst information, the conflict interval reduction is limited to the synchronization segment, which reduces the conflict probability and can effectively improve the system user capacity.