Title
Gridless Quadrature Compressive Sampling with Interpolated Array Technique.
Abstract
Quadrature compressive sampling (QuadCS) is a sub-Nyquist sampling scheme for acquiring in-phase and quadrature (I/Q) components in radar. In this scheme, the received intermediate frequency (IF) signals are expressed as a linear combination of time-delayed and scaled replicas of the transmitted waveforms. For sparse IF signals on discrete grids of time-delay space, the QuadCS can efficiently reconstruct the I/Q components from sub-Nyquist samples. In practice, the signals are characterized by a set of unknown time-delay parameters in a continuous space. Then conventional sparse signal reconstruction will deteriorate the QuadCS reconstruction performance. This paper focuses on the reconstruction of the I/Q components with continuous delay parameters. A parametric spectrum-matched dictionary is defined, which sparsely describes the IF signals in the frequency domain by delay parameters and gain coefficients, and the QuadCS system is reexamined under the new dictionary. With the inherent structure of the QuadCS system, it is found that the estimation of delay parameters can be decoupled from that of sparse gain coefficients, yielding a beamspace direction-of-arrival (DOA) estimation formulation with a time-varying beamforming matrix. Then an interpolated beamspace DOA method is developed to perform the DOA estimation. An optimal interpolated array is established and sufficient conditions to guarantee the successful estimation of the delay parameters are derived. With the estimated delays, the gain coefficients can be conveniently determined by solving a linear least-squares problem. Extensive simulation results evidently demonstrate the superiority of the proposed algorithms in achieving super-resolution time-delay estimation and high-accuracy sparse signal reconstruction. Quadrature compressive sampling system is described in the frequency domain.A beamspace DOA-based formulation is established for gridless sparse reconstruction.Time-delays are estimated with interpolated arrays.Sufficient condition to guarantee the estimation of the delay parameters is derived.
Year
DOI
Venue
2015
10.1016/j.sigpro.2016.10.010
Signal Processing
Keywords
Field
DocType
Compressed sensing,Quadrature sampling,Beamspace DOA estimation,Interpolated array
Frequency domain,Linear combination,Beamforming,Mathematical optimization,Interpolation,Parametric statistics,Quadrature (mathematics),Compressed sensing,Mathematics,Signal reconstruction
Journal
Volume
Issue
ISSN
abs/1503.00436
C
0165-1684
Citations 
PageRank 
References 
5
0.44
33
Authors
4
Name
Order
Citations
PageRank
Feng Xi14411.75
Shengyao Chen26513.93
Yimin Zhang31536130.17
Zhong Liu4735.31