Design of Cognitive Radio Multi-User Multi-Channel Protocol Based on Matching Theory in Wireless Communications

Cognitive radio can sense the spectrum environment in real-time, and dynamically allocate the channel not occupied by the primary user (PU) to the secondary user (SU), which effectively solves the problem that the demand for spectrum resources caused by the surge of wireless communication technology and services is contradictory with the actual spectrum utilization. While considering the improvement of spectrum utilization, it is also important to find a suitable match between SU and idle channels to improve user satisfaction. Top Trading Cycles (TTC) and Boston (BOS)matching theory are applied to find the optimal match, and two preference ordering matrices are defined from SU and channel perspective respectively. The channel preference ranking of SU is based on the transmission rate of the user on different channels, and the channel preference ranking is based on the quotation of the user on the channel. Based on the existing preference matrix, TTC and BOS are used for allocation. The experimental results show that, compared with the existing DA matching theory, TTC is superior to DA and BOS allocation protocols in average throughput, average delay, average length, and average rejection rate. Compared with DA and TTC, BOS has lower allocation time. Therefore, when users and channels are matched, TTC is used to enable SU to obtain a channel with a faster transmission rate and higher satisfaction. When users need to quickly match channels, BOS mode is adopted to achieve an efficient and optimal allocation effect.