Optimization Method for Wide Beam Sonar Transmit Beamforming

Abstract

Imaging and mapping sonars such as forward-looking sonars (FLS) and side-scan sonars (SSS) are sensors frequently used onboard autonomous underwater vehicles. To acquire information from around the vehicle, it is desirable for these sonar systems to insonify a large area; thus, the sonar transmit beampattern should have a wide field of view. In this work, we study the problem of the optimization of wide transmission beampatterns. We consider the conventional phased-array beampattern design problem where all array elements transmit an identical waveform. The complex weight vector is adjusted to create the desired beampattern shape. In our experiments, we consider wide transmission beampatterns (≥20∘) with uniform output power. In this paper, we introduce a new iterative-convex optimization method for narrowband linear phased arrays and compare it to existing approaches for convex and concave–convex optimization. In the iterative-convex method, the phase of the weight parameters is allowed to be complex as in disciplined convex–concave programming (DCCP). Comparing the iterative-convex optimization method and DCCP to the standard convex optimization, we see that the former methods archive optimized beampatterns closer to the desired beampatterns. Furthermore, for the same number of iterations, the proposed iterative-convex method achieves optimized beampatterns, which are closer to the desired beampattern than the beampatterns achieved by optimization with DCCP.

Fast Low-Sidelobe Pattern Synthesis Using the Symmetry of Array Geometry

“…Convex optimization shows supreme performance in finding the optimal solutions at the expense of modeling difficulty. Due to the quadratic nature of the array pattern expression, second-order cone programming (SOCP) and semidefinite programming (SDP) have gained widespread applications in array pattern synthesis [16][17][18][19][20][21][22][23][24][25]. Nevertheless, for convex optimization methods, the problem models vary with the optimization purposes, and most problems appear to be non-convex.…”

Phase-only array transmit beamforming without iterative/numerical optimization methods

“…In fact, the constant modulus constraint makes the problem nonconvex and NP-hard (Cong et al, 2022). To solve it, some solutions are obtained through a semidefinite relaxation of the constraint to transform the optimization problem into a convex problem that can be solved by means of well-known numerical tools [ (Gershman et al, 2010;Tranter et al, 2016;Tranter et al, 2017;Rixon Fuchs et al, 2022), and references therein]. Other existing strategies exploit statistical and evolutionary methods to find solutions as close as possible to the optimal one (Hatam, 2022).…”

Accurate and Low-Power Ultrasound–Radiofrequency (RF) Indoor Ranging Using MEMS Loudspeaker Arrays

“…MUSIC, ESPRIT, GCC-PHAT, and beamforming are widely used techniques to determine the direction of arrival (DoA) of received signals [ 24 ]. Through beamforming, for example, sonar is able to construct one or more directional beams simultaneously to perform fine-grained target detection [ 25 ]. While loudspeaker arrays have been applied in a variety of fields, such as haptic control, object levitation, medical examination, and non-destructing testing, their application in acoustic localization has been very limited so far.…”