This paper describes a wideband transmitting adaptive digital beamforming (ADBF) scheme with nulls in the direction of interference. The scheme partitions the wideband transmit signal into independent sub-bands using an analysis filter bank behind each array element. In each channel, sub-band ADBF weight vector is computed based on the minimum variance criterion with multiple linear constraints to form the sub-band transmit beam. Finally, a wideband transmit adaptive beam is reconstructed through the synthesis filters. Theoretical analysis and simulation experiments show that this algorithm can form a wideband transmit beam with deep nulls, and the pointing direction of the null keeps unchanged regardless of frequency. The algorithm proposed in this paper has little computation load and is efficient to implement in engineering applications.
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