A Novel Transceiver Design for OFDM Systems in Time-Varying Channels with Adaptive Cyclic Prefix

Abstract

Cyclic prefix (CP) is widely employed in orthogonal frequency division multiplexing (OFDM) systems, primarily due to its effectiveness in mitigating multipath interference and facilitating simplified receiver-side equalization. However, conventional CP-aided OFDM systems incur a loss in spectral efficiency, particularly under channel conditions with substantial maximum delay spreads, thereby posing a critical limitation for next-generation wireless communications. To address this issue, we develop an adaptive CP-based OFDM transceiver, wherein the CP duration is dynamically optimized according to time-varying channel characteristics, significantly reducing prefix overhead. Simulation results demonstrate that the proposed scheme yields notable improvements in bandwidth efficiency while preserving bit error rate (BER) performance comparable to that of traditional OFDM systems.