一种适用于OFDM系统的块状导频自适应方案

An Adaptive Block Pilot Scheme for OFDM Systems

针对传统OFDM系统导频插入密度固定所导致的信道利用率较低的弊端,研究了块状导频的插入方法、自适应策略与传输信令.导频间信道状态一致时,OFDM信道估计精度主要取决于导频密度,因此,通过控制导频密度,提出了一种改进的块状导频自适应方案,在满足系统误码率要求的前提下可有效提高OFDM系统的信道利用率.仿真结果表明该方案可以实现通信需求与导频的自动匹配,在保证系统性能的同时有效降低导频密度.

The inset method,modulation technique and transmit channel of block pilot signal was researched in order to improving the low channel using efficiency which brought by fixation of inset pilot density in traditional OFDM.Therefore an adaptive block pilot scheme with low complexity was proposed in response to a traditional OFDM system with fixed pilot having a lack of channel utilization.It is designed to react to environmental conditions and reduces the overall pilot overhead when ideal performance is guaranteed.Furthermore,placement of pilot signals and signaling to facilitate this adaptive operation were also addressed.Simulation results showed that the proposed scheme remarkably improves system performance with low pilot overhead compared to conventional schemes.