# An Under-Sampling Array Signal Processing Method Based on Improved Hadamard Matrix
## Nomenclature  
* [1] [PERSON]; [PERSON] Two decades of array signal processing research: The parametric approach. _IEEE Signal Process. Mag._**1996**, _13_, 67-94. [CrossRef]
* [2] [PERSON]; [PERSON] Performance analysis of adaptive array signal processing algorithms. _IETE Tech. Rev._**2016**, _33_, 472-491. [CrossRef]
* [3] [PERSON]; [PERSON]; [PERSON] Target azimuth estimation in the presence of linear array shape distortion. In Proceedings of the 2015 8 th International Congress on Image and Signal Processing (CISP), Shenyang, China, 14-16 October 2015. * [4] [PERSON]; [PERSON]; [PERSON]; [PERSON]; [PERSON] Optimal measurements for resolution beyond the Rayleigh limit. _Opt. Lett._**2017**, _42_, 231-234. [CrossRef] [PubMed]
* [5] [PERSON] High-resolution frequency-wavement spectrum analysis. _Proc. IEEE_**1969**, _57_, 1408-1418. [CrossRef]
* [6] [PERSON] Multiple emitter location and signal parameter estimation. _IEEE Trans. Antennas Propag._**1986**, _34_, 276-280. [CrossRef]
* [7] [PERSON]; [PERSON]; [PERSON]; [PERSON]; [PERSON] A novel DOA estimation algorithm based on eigen space. In Proceedings of the 2007 International Symposium on Microwave, Antenna, Propagation and EMC Technologies for Wireless Communications, Hangzhou, China, 16-17 August 2007. * [8] [PERSON] Compressed sensing. _IEEE Trans. Inf. Theory_**2006**, _52_, 1289-1306. [CrossRef]
* [9] [PERSON]; [PERSON]; [PERSON] Spatial-Resampling Wideband Compressive Beamforming. In Proceedings of the OCEANS 2021: San Diego--Porto, San Diego, CA, USA, 20-23 September 2021. * [10] [PERSON]; [PERSON]; [PERSON]; [PERSON] On the virtual array concept for higher order array processing. _IEEE Trans. Signal Process._**2005**, _53_, 1254-1271. [CrossRef]
* [11] [PERSON]; [PERSON]; [PERSON] DOA Estimation of Quasi-Stationary Signals with Less Sensors Than Sources and Unknown Spatial Noise Covariance: A Khatri-Rao Subspace Approach. _IEEE Trans. Signal Process._**2010**, _58_, 2168-2180. [CrossRef]
* [12] [PERSON] Minimum-redundancy linear arrays. _IEEE Trans. Antennas Propag._**1968**, _16_, 172-175. [CrossRef]
* [13] [PERSON]; [PERSON] The unifying role of the coarray in aperture synthesis for coherent and incoherent imaging. _Proc. IEEE_**1990**, _78_, 735-752. [CrossRef]
* [14] [PERSON]; [PERSON] Nested Arrays: A Novel Approach to Array Processing with Enhanced Degrees of Freedom. _IEEE Trans. Signal Process._**2010**, _58_, 4167-4181. [CrossRef]
* [15] [PERSON]; [PERSON]; [PERSON] Single-Snapshot Nested Virtual Array Completion: Necessary and Sufficient Conditions. _IEEE Signal Process. Lett._**2022**, _29_, 1-5. [CrossRef]
* [16] [PERSON]; [PERSON] Sparse Sensing with Co-Prime Samplers and Arrays. _IEEE Trans. Signal Process._**2011**, _59_, 573-586. [CrossRef]
* [17] [PERSON]; [PERSON]; [PERSON] Direction estimation using compressive sampling array processing. In Proceedings of the 2009 IEEE/SP 15 th Workshop on Statistical Signal Processing(SSP), Cardiff, UK, 31 August-3 September 2009. * [18] [PERSON]; [PERSON] DOA estimation based on compressive sampling array with novel beamforming. In Proceedings of the 2014 XXXth URSI General Assembly and Scientific Symposium (URSI GASS), Beijing, China, 16-23 August 2014. * [19] [PERSON]; [PERSON]; [PERSON] Direction estimation under compressive sensing framework: A review and experimental results. In Proceedings of the 2011 IEEE International Conference on Information and Automation(ICIA), Shenzhen, China, 6-8 June 2011. * [20] [PERSON] Music DOA estimation with compressive sensing and/or compressive arrays. In Proceedings of the 2011 IEEE International Symposium on Antennas and Propagation (APSURSI), Spokane, WA, USA, 3-8 July 2011. * [PERSON] et al. (2014) [PERSON]; [PERSON]; [PERSON] Bearing estimation of coherent signals using compressive sampling array. In Proceedings of the 2014 IEEE International Instrumentation and Measurement Technology Conference (I2 MTC) Montevideo, Montevideo, Uruguay, 12-15 May 2014. * [PERSON] et al.