The genetic algorithm is used to synthesize the radiation pattern of the directional circular arc array to minimize the bit error rate (BER) performance in indoor wireless communication system. The impulse responses of the indoor channel for any transmitter-receiver location are computed by shooting and bouncing ray/image techniques. By using the impulse response of multipath channel, the performance of the synthesized antenna pattern on BPSK (binary phase shift keying) system with phase and timing recovery circuits can be calculated. Based on the topography of the antenna and the BER formula, the synthesis problem can be reformulated into an optimization problem and solved by the genetic algorithm. The novelty of our approach is choosing BER as the object function instead of sidelobe level of the antenna pattern, i.e., BER performance is defined as a object function to optimize the excitation coefficient of array by the genetic algorithm. The strong point of the genetic algorithm is that it can find out the solution even if the performance index cannot be formulated by simple equations. Besides, the genetic algorithm will converge to global extreme instead of local extreme and achieves a good antenna pattern. Numerical results show that the synthesized antenna pattern is effective to combat the multipath fading and can increase the transmission rate of indoor millimeter wave system.
關聯:
Wireless Personal Communications 42(4), pp.575-586
