다중 경로 페이딩 채널에서 Bi-orthogonal Modulation을 이용한 Multi-code Parallel Combinatory CDMA System의 성능 개선

Performance Improvement of Multi-Code Parallel Combinatory CDMA Systems Using Bi-Orthogonal Modulation under Multipath Fading Environment

In this paper, we present the performance of a multi-code parallel combinatory CDMA system using bi-orthogonal modulation under multipath fading channel. In general, the dynamic range of the amplitude of the transmit signal is very large in conventional multi-code CDMA systems, resulting in severe nonlinear distortion due to high power amplifier and thus significant BER performance degradation. Since the number of simultaneously multiplexed code channels in the proposed system is reduced, the proposed system exhibits reduction of peak-to-average power ratio (PAPR) of the transmit signal amplitude with significant BER improvement. We verify the performance of the proposed system by computer simulations under the Vehicular B multipath fading channel model by ARIB.