In this lecture we present the principles of adaptive beamforming, the problem of estimating the adaptive weights and several associated practical problems, like preserving low sidelobe patterns, using subarrays and GSLC configurations. We explain the detection problem with adaptive arrays and the methods for angle estimation. Finally the methods for resolution enhancement (super-resolution met...

We propose and demonstrate a novel apodization technique for an elliptical-core two-mode fiber acousto-optic filter by twisting the fiber and adjusting the acoustic polarization. The sidelobe suppression in the filter spectrum was improved from -9.7 to -15.5 dB. A theoretical analysis that includes acoustic birefringence explains the experimental results with good agreement.

Random-process autocorrelations and crosscorrelations in three dimensions here provide computationally efficient mean-square-error and average-gain measures to control main beam and sidelobe characteristics in convex optimization of far-field beamforming coefficients for large wideband arrays. An example optimized with the ultra-efficient interior-point code LOQO illustrates.

N -continuous OFDM is a modulation technique that has a lower sidelobe than the original OFDM as a result of the continuous connection with its higher-order derivatives between the OFDM symbols. However, N -continuous OFDM has a high symbol error rate. In the present paper, we improve N -continuous OFDM without increasing the symbol error rate by using a selected mapping technique.

A new technique is proposed for the design of circular antenna arrays using particle swarm optimization. The design problem has been formulated to achieve a desired beamwidth and sidelobe level. This is accomplished by jointly optimizing the excitation amplitude and phase. The results obtained show improvement over conventional linear programming method.