An adaptive signal-to-noise ratio estimator in mobile communication channels
An adaptive signal-to-noise ratio estimator in mobile communication channels
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DOI：
10.1016/j.dsp.2009.09.004
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发表时间：
2010-05-01
影响因子：
2.9
通讯作者：
Li, Gang
中科院分区：
文献类型：
--
作者：
Hua, Jingyu;Meng, Limin;Li, Gang
信噪比（SNR）是移动的传播信道中的一个重要参数，它直接反映了信道的接收状况，因此在系统性能评估和自适应应用中有着广泛的应用。因此，本文提出了一种适用于移动的通信系统的频域信噪比估计方法，该方法利用带限衰落信道和加性白色高斯噪声的信号模型。利用上述模型，可以从信道加噪声信号的周期图中估计噪声功率谱密度，随后导致我们的SNR估计。此外，为了降低快速傅里叶变换在周期图计算中的固有频谱泄漏，解析推导了泄漏表达式，并提出了一种自适应处理方法，在泄漏减少和噪声平滑之间进行权衡。我们通过仿真验证了我们的算法，并在很宽的速度和信噪比范围内观察到高精度。此外，与传统方法不同的是，所提出的估计器不严格基于特定多普勒频谱形状的假设，只考虑了有限带宽信道的要求，因此对一般移动的信道具有鲁棒性。(C)2009 Elsevier Inc. All rights reserved.
Representing the reception condition directly, signal-to-noise ratio (SNR) is an important parameter in mobile propagation channels, and therefore is widely used in system performance evaluations and adaptive applications. Hence, this paper puts forward a frequency domain SNR estimator in mobile communications, where we exploit the signal model with the band-limited fading channel and the additive white Gaussian noise. With the above model, the noise power spectrum density can be estimated from the periodogram of channel-plus-noise signals, subsequently leading to our SNR estimation. Moreover, in order to degrade the intrinsic spectrum leakage of fast Fourier transform in periodogram calculation, the leakage expression is derived analytically and then an adaptive process is proposed to make a tradeoff between leakage reduction and noise smoothing. We verify our algorithm by simulations and observe high accuracy in a wide range of velocities and SNRs. Additionally, unlike the conventional work, the proposed estimator is not strictly based on the assumption of specific Doppler spectral shapes except for the requirement of the band-limited channel, hence it is robust to general mobile channels. (C) 2009 Elsevier Inc. All rights reserved.