A Hybrid Analog-Digital Adaptive Beamforming in Time-Modulated Linear Arrays

Abstract An adaptive beamforming based on a hybrid analog–digital scheme in time-modulated linear arrays is proposed. Since the time-modulated linear array has many sidebands, the adaptive beamforming can be realized at the first positive sideband by only controlling the switch-on time sequences of each element without using any attenuator, phase shifter, or analog multiplier in the beamforming structure. An S-band eight-element double-layered printed dipole linear array was used to verify the pattern synthesis experimentally. The bit error rate of the proposed adaptive beamforming in the time-modulated linear array is simulated by using a binary phase shift keying signal, and good performance is obtained.

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