Multi-beamforming with uniform linear array and algebraic integer quantization based DCT

Aperture arrays are widely used in beamforming applications where element signals are steered to a particular direction of interest and a single beam is formed. Multi-beamforming is an extension of single beamforming which is desired in the fields where sources located in multiple directions are of interest. Discrete Fourier Transform (DFT) is usually used in these scenarios to segregate the received signals based on their direction of arrivals. In this work, instead of DFT, the Discrete Cosine Transform (DCT) is used and an efficient implementation technique using Decomposed Algebraic Integer Quantization (DAIQ) is proposed for error-free and multiplier-less implementation of the DCT. Its performance for beamforming application is also studied.