Nonlinear distortions generated by the power amplifier (PA) will affect the performance of channel estimation thus the veracity of signal detection for ultra-wideband (UWB) orthogonal frequency-division multiplexing (OFDM) systems. The existing nonlinear cancellation techniques for tackling this problem reduce the overhead of the system due to the large number of pilot subcarriers required. As the UWB channel can usually be modeled as sparse, an iterative method that estimates the sparse channel and recovers the original signal, referred to as SCE-DSD, is proposed in this letter. Involving the nonlinear distortion in the measurement matrix construction, SCE-DSD estimates the channel and the original signal sequentially. The numerical results show that, compared to the state-of-the-art method, the proposed method has a better performance using a smaller number of pilot subcarriers.

中文翻译：

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结合失真信号检测的 UWB OFDM 系统稀疏信道估计方案


功率放大器（PA）产生的非线性失真将影响信道估计的性能，从而影响超宽带（UWB）正交频分复用（OFDM）系统信号检测的准确性。由于需要大量的导频子载波，现有的用于解决该问题的非线性消除技术减少了系统的开销。由于UWB信道通常可以被建模为稀疏信道，因此本文提出了一种估计稀疏信道并恢复原始信号的迭代方法，称为SCE-DSD。 SCE-DSD在测量矩阵构造中涉及非线性失真，依次估计信道和原始信号。数值结果表明，与最先进的方法相比，所提出的方法使用较少数量的导频子载波具有更好的性能。