On the Design of Robust Multiband Ofdm Ultra-wideband Receivers

This paper analyzes the effects of narrowband interferences (NBI) on the performance of a multi-band orthogonal frequency division multiplexing (MB-OFDM) Ultra-wideband (UWB) receiver and proposes efficient schemes for signal reception and extraction of information in the presence of NBI. A study to assess the effects of NBI on the quantization noise in the analog to digital converter (ADC) is conducted. It is found that a reduced-complexity digital frequency excision method is sufficient to compensate weak NBI (with signal-to-interference ratio (SIR) larger than 0 dB). To combat efficiently strong NBI (with SIR less than 0 dB), this paper proposes a novel mixed interference suppression scheme that relies on the joint cooperation between a digital NBI detector and an adaptive analog notch filter. Simulation results show that the proposed mixed suppression scheme improves the performance of the digital frequency excision scheme by as much as 9 dB.