Robust, Low Complexity and Energy Efficient Baseband Receiver Design for MB-OFDM UWB.

摘要

Ultra-wideband (UWB) technology, targeting at wireless personal area networks (WPANs),brings the convenience of high-speed and short-range wireless interconnects. As a novel communication technique, multi-band orthogonal frequency division multiplexing (MB-OFDM) UWB has the features of high spectrum efficiency, multiple access capability and robustness against narrow band interference. However, its inherent high complexity and the requirement of powerful processing for good performance are the obstacles for practical application.;Synchronization plays the key role for the performance of the whole baseband receiver system. In this dissertation, a dual-threshold (DT) packet detection scheme is proposed for timing synchronization. Compared with traditional cross-correlation algorithm, DT has much better detection performance, especially in high noise environment.;As an OFDM-based system, MB-OFDM UWB is vulnerable and sensitive to carrier frequency offset (CFO). We employ multipartite table method (MTM) to implement arctangent and sin/cos functions for frequency synchronization. Compared with traditional algorithms, MTM has the advantages of low cost, low power consumption and higher processing speed. Residual phase distortion is corrected by a highly simplified phase tracking method, which also has better performance compared with traditional phase tracking scheme.;Architectures of matched filter in packet detector, CFO corrector, FFT output reorder buffer and phase tracking block are optimized for low complexity. Implemented in O.13-mum CMOS technology, the proposed baseband receiver system has the core area of 2.5 mm2 and the estimated power consumption is 170 mW, which is equivalent to the energy efficiency of 88 pJ/b at 480 Mbps data rate. The implementation results verify the robustness, low complexity and power efficiency of the proposed MB-OFDM UWB baseband receiver.