Multi‐beam RF aperture using multiplierless FFT approximation. Issue 24 (1st November 2014)

• Record Type: Journal Article
• Authors: Suarez, D.; Cintra, R. J.; Bayer, F. M.; Sengupta, A.; Kulasekera, S.; Madanayake, A.
• Is Part Of: Electronics letters. Volume 50:Issue 24(2014)
• Page Start: 1788
• Page End: 1790
• Publication Date: 2014-11-01
• Subjects: approximation theory -- radio networks -- fast Fourier transforms -- antenna arrays -- CMOS integrated circuits -- field programmable gate arrays; multibeam RF aperture -- multiplierless FFT approximation -- multiple independent radio frequency -- RF beams -- radio astronomy -- microwave imaging -- radar imaging -- fast Fourier transform -- receiver antenna array -- multiplier complexity -- multiplierless approximation -- RF beamforming -- antenna array patterns -- FFT based beamformer -- RF multibeam receivers -- complementary metal oxide semiconductor -- CMOS technology -- field programmable gate array -- FPGA device -- CMOS simulation; Electronics -- Periodicals; 621.381
• DOI: 10.1049/el.2014.3561
• Languages: English
• ISSNs: 0013-5194

Abstract

Abstract : Multiple independent radio‐frequency (RF) beams find applications in communications, radio astronomy, radar and microwave imaging. An N ‐point fast Fourier transform (FFT) applied spatially across an array of receiver antennas provides N ‐independent RF beams at N /2 log2 N multiplier complexity. Here, a low‐complexity multiplierless approximation for the 8‐point FFT is presented for RF beamforming, using only 26 additions. The algorithm provides eight beams that closely resemble the antenna array patterns of the traditional FFT‐based beamformer albeit without using multipliers. The proposed FFT‐like algorithm was verified on‐chip using a Xilinx Virtex‐6 Lx240T field programmable gate array (FPGA) device. The FPGA implementation indicated bandwidth of 369 MHz for each of the independent receive‐mode RF beams.