White noise reduction for wideband linear array signal processing

Abstract

The performance of wideband array signal processing algorithms is dependent on the noise level in the system. A method is proposed for reducing the level of white noise in wideband linear arrays via a judiciously designed spatial transformation followed by a bank of highpass filters. A detailed analysis of the method and its effect on the spectrum of the signal and noise is presented.The reduced noise level leads to a higher signal to noise ratio (SNR) for the system, which can have a significant beneficial effect on the performance of various beamforming methods and other array signal processing applications such as direction of arrival (DOA) estimation. Here we focus on the beamforming problem and study the improved performance of two well-known beamformers, namely the reference signal based (RSB) and the linearly constrained minimum variance (LCMV) beamformers.Both theoretical analysis and simulation results are provided. Index TermsWhite noise reduction, uniform linear arrays, nonuniform linear arrays, wideband beamforming, direction of arrival estimation, performance analysis.

Robust wideband beamforming method for linear frequency modulation signals based on digital dechirp processing

“…In [21–23], a method via a judiciously designed spatial transformation followed by a bank of highpass filters has been proposed to mitigate the effect of white noise without affecting the directional signals in wideband arbitrary linear arrays. With this method, a maximum 3 dB improvement in total power‐to‐total‐noise‐power ratio (TSNR) can be achieved in the ideal case, but the amount of calculation has been greatly increased.…”

Novel method for digital beamforming in co‐prime sensor arrays using product and min processors

“…This section aims to investigate computational complexity of the proposed method in the CSA compared to the full ULA and the CSA prod processor. The general equation for computing the beam pattern of full ULA, AF s1 , AF s2 , AF d1 , and AF d2 is given by (2), where N is proportional to the number of array elements. In accordance with the above equation, in a full ULA with N = N 1 × N 2 elements for calculating a pattern at a certain angle (such as θ), N−1 summation, and N multiplication operations are required.…”

“…The array of sensors is widely used in many fields of technology, such as wireless communication, radar, sonar, microphone arrays, radio surveillance, and so on. Beamforming and direction of arrival (DOA) estimation are two main areas of signal processing for narrowband and wideband sensor array [1, 2]. The maximum spatial resolution of beam‐forming and DOA estimation algorithms is achieved by maximising the array aperture.…”

Improved Main Lobe Cancellation Method for Suppression Directional Noise in HFSWR Systems

“…Due to the unique properties of directional noise, existing methods cannot be applied directly and need to be improved accordingly. In [31], the wideband linear array white noise is reduced by a judiciously designed spatial transformation followed by a bank of highpass filters. J. Xiong et al [32] presented a cascade model consisting of a noise estimation network based on U-Net and a recognition network based on MSCANet.…”