One-Bit LFM Pulse Radar: Harmonic Analysis and Target Reconstruction

Abstract

One-bit radar, adopting one-bit analog-to-digital converters to perform signal sampling and quantization, is a promising technology for low-cost and resource-limited applications. In this paper, effects of one-bit quantization on the linear signal processing for the one-bit linear frequency modulated pulse radar are studied and a target reconstruction approach is proposed. Firstly, characteristics of 3-order harmonics of the one-bit signal are analyzed. It is indicated that when conventional linear signal processing methods are carried out, 3-order harmonics may not only raise the detection background but also result in false alarms. Secondly, a two-stage approach jointly performing the linear and nonlinear signal processing is proposed to suppress harmonics and recover true targets. Specifically, in the first stage, the linear signal processing is carried out to suppress unmatched harmonics and dimension reduction. In the second stage, based on a dimension-reduced signal observation model, generalized approximate message passing is utilized to suppress matched harmonics and recover true targets. The effectiveness of the proposed approach is demonstrated by numerical results.

Parameter estimation and CRB analysis of 1‐bit colocated MIMO radar

“…For the elimination of the influence of false targets, a two-stage target detection approach, termed dimension reduction generalised-approximatemessage-passing (DR-GAMP), was proposed. In [1,[14][15][16][17], there is a common interesting phenomenon: for 1-bit quantisation, a higher SNR does not necessarily lead to better parameter estimation performance. This phenomenon is worthy of further discussion to clarify the influence of the SNR on 1-bit sampling.…”

“…Both random dithering and the time-varying threshold are essentially equivalent to adding random noise to the original signal before sampling, which implies that the signal-to-noise ratio (SNR) is reduced. In [17,18], a 1-bit linear frequency modulated continuous wave radar was studied. The signal decomposition form of a 1-bit sampled signal indicates that 1-bit sampling may give rise to false targets.…”

Signal Processing of Coast-Ship Bistatic High-Frequency Surface-Wave Radar Using One-Bit Quantized Measurement

“…The coming challenge is how to reduce equipment costs. Recently, a low-cost radar technology, one-bit quantization technology, has emerged [10], [11]. One-bit quantization refers to a one-bit analog-to-digital Converter.…”

“…Also for one-bit sampling with time-varying thresholds in [26], the target estimation is formulated as a multivariate weighted-least-squares optimization problem that can be solved in a cyclic manner. In [11], one-bit linear frequency modulated continuous wave (LFMCW) radar was studied and a two-stage target detection approach termed as dimension reduction generalized-approximate-messagepassing (DR-GAMP) was proposed. It is worth noting that in [10], [11], [24]- [26], there is a common interesting phenomenon: for one-bit quantization, higher SNR does not necessarily lead to better parameter estimation performance.…”