Transmit Multi-beamforming for Colocated Uniform Linear Array Using MISL Beamformers

摘要

This paper considers transmit multi-beamforming for colocated uniform linear array (ULA). First, the colocated ULA emitting sum of independent ortho-normal baseband waveforms by each element is briefly introduced, and its transmit beampattern expressed by the sum of sub-beampatterns of all the waveforms is formulated. Then the beamforming algorithms using the criterion of minimum integrated sidelobe level (MISL) for different types of steering angle-space are proposed. The algorithms can be summarized by optimizing the weighting coefficients of each waveform, which controls one sub-beampattern, to form a beam based on parallel MISL beamformers. And each beamformer is then converted to a Rayleigh quotient (RQ) minimization in which the optimal closed-form solutions can be obtained. Finally, numerical comparisons and computational complexity analyses are provided to validate the MISL beamformers.