4 research outputs found
Optimum sparse subarray design for multitask receivers
The problem of optimum sparse array configuration to maximize the beamformer output signal-to-interference plus noise ratio (MaxSINR) in the presence of multiple sources of interest (SOI) has been recently addressed in the literature. In this paper, we consider a shared aperture system where
optimum sparse subarrays are allocated to individual SOIs and collectively span the entire full array receiver aperture. Each
subarray may have its own antenna type and can comprise a different number of antennas. The optimum joint sparse subarray design for shared aperture based on maximizing the
sum of the subarray beamformer SINRs is considered with and without SINR threshold constraints. We utilize Taylor series approximation and sequential convex programming (SCP) techniques to render the initial non-convex optimization a convex
problem. The simulation results validate the shared aperture design solutions for MaxSINR for both cases where the number of sparse subarray antennas is predefined or left to comstitute an optimization variable
Multi-stage Antenna Selection for Adaptive Beamforming in MIMO Arrays
Increasing the number of transmit and receive elements in
multiple-input-multiple-output (MIMO) antenna arrays imposes a substantial
increase in hardware and computational costs. We mitigate this problem by
employing a reconfigurable MIMO array where large transmit and receive arrays
are multiplexed in a smaller set of k baseband signals. We consider four stages
for the MIMO array configuration and propose four different selection
strategies to offer dimensionality reduction in post-processing and achieve
hardware cost reduction in digital signal processing (DSP) and radio-frequency
(RF) stages. We define the problem as a determinant maximization and develop a
unified formulation to decouple the joint problem and select antennas/elements
in various stages in one integrated problem. We then analyze the performance of
the proposed selection approaches and prove that, in terms of the output SINR,
a joint transmit-receive selection method performs best followed by
matched-filter, hybrid and factored selection methods. The theoretical results
are validated numerically, demonstrating that all methods allow an excellent
trade-off between performance and cost.Comment: Submitted for publicatio