Beamforming with extended co-prime sensor arrays

Abstract

Co-prime sensor arrays (CSAs) interleave two uniform linear subarrays that are undersampled by co-prime factors. The resulting nonuniform array requires far fewer sensors to match the spatial resolution of a fully populated ULA of the same aperture. Choosing the co-prime undersampling factors as close to equal as possible minimizes the number of sensors in the CSA. However, the peak side lobe of the CSA is higher than the peak side lobe of the equivalent full uniform linear array (ULA). Increasing the number of sensors in the CSA subarrays by half while maintaining the interelement spacing gurarantees that the CSA peak side lobe is less than that of the full aperture ULA when both arrays use rectangular windows.

Gaussian signal detection by coprime sensor arrays

“…A coprime sensor array (CSA) interleaves two aliased ULAs with undersampling factors N and M respectively where N and M are coprime [5][6][7][8]. Subarray A and Subarray B of a basic CSA have M and N sensors respectively and the subar rays share the first sensor as shown in Figure 1.…”

“…Adding sensors to the subarrays while keeping their intersensor spacings fixed reduces the peak side lobe height [5,8]. This paper assumes that the numbers of sensors in the subarrays differ by one to 978-1-4673-6997-8/15/$3l.00 ©2015 IEEE minimize the total number of sensors [7] and the subarrays are extended to Me = 3M /2 and N e = 3M /2 + 1 sensors to reduce the peak side lobe height to half of the full ULA with equivalent aperture. The CSA with the added sensors in the subarrays is called extended CSA (ECSA).…”

Extending coprime sensor arrays to achieve the peak side lobe height of a full uniform linear array

“…As we demonstrated in [14], the valid optimal coprime pair is the one that has M and N as close as possible. For L = 30, the coprime pair (5, 6) is optimal in minimizing the total number of sensors.…”

Angular Resolution Enhancement Provided by Nonuniformly-Spaced Linear Hydrophone Arrays in Ocean Acoustic Waveguide Remote Sensing

“…Co-prime arrays [32,33], on the other hand, combine subapertures with uniform inter-element spacings that are non-integral multiples of each other. Like nested arrays, co-prime arrays are also widely exploited to enhance beamwidth in active and passive radar sensing, as well as in grating lobe suppression [34,35].…”