Effects of Phase Quantization on Digital Beamforming for HF Phased Array Radar

Digital beamforming (DBF) are efficient techniques for implementation of reconfigurable radars. Digital implementation can be carried out using finite precision and infinite precision representation of the phased array signal. We consider finite precision representation, since it takes considerably less implementation resources compared with the infinite case. In this paper we evaluate FPGA implementation when quantization is introduced in the phasing network. Digital samples of phased signals are sensitive to finite precision. Finite precision reduces mainlobe level as well as sidelobe gain. For multiple beam generation, it degrades not only the transmitted beam but adjacent beams as well. The quantization effects depend on position of the quantizer. They are different when the quantizer is placed before and after beamforming network. Simulations have been performed to demonstrate the results