Pragmatic trellis coded modulation for adaptive multi-objective genetic algorithm-based cognitive radio systems

The cognitive radio (CR) has recently been proposed as one of the main opportunistic spectrum access solutions for dynamic spectrum allocation. In the CR context, an adaptive wireless node changes its transmission parameters to communicate efficiently and avoid interference with licensed users. In this paper, an adaptive pragmatic trellis coded modulation (TCM) scheme is proposed for CR systems. The proposed scheme employs the family of pragmatic TCM to combine different coded modulation modes to serve the CR node adaption while reducing the hardware complexity. The tradeoff of the error-throughput-power consumption performance is first analyzed using the so-called Pareto front concept. Then, the pragmatic TCM modes are implemented into a multi-objective genetic algorithm (MOGA) based CR decision engine. It is demonstrated that the proposed system is able to evolve to an appropriate transmission mode based on the wireless environmental conditions.