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Title: Analog vs. Digital Spatial Transforms: A Throughput, Power, and Area Comparison
Spatial linear transforms that process multiple parallel analog signals to simplify downstream signal processing find widespread use in multi-antenna communication systems, machine learning inference, data compression, audio and ultrasound applications, among many others. In the past, a wide range of mixed-signal as well as digital spatial transform circuits have been proposed-it is, however, a longstanding question whether analog or digital transforms are superior in terms of throughput, power, and area. In this paper, we focus on Hadamard transforms and perform a systematic comparison of state-of-the-art analog and digital circuits implementing spatial transforms in the same 65 nm CMOS technology. We analyze the trade-offs between throughput, power, and area, and we identify regimes in which mixed-signal or digital Hadamard transforms are preferable. Our comparison reveals that (i) there is no clear winner and (ii) analog-to-digital conversion is often dominating area and energy efficiency-and not the spatial transform.  more » « less
Award ID(s):
1717559 2002921
Author(s) / Creator(s):
; ; ; ; ;
Date Published:
Journal Name:
IEEE 63rd International Midwest Symposium on Circuits and Systems (MWSCAS)
Page Range / eLocation ID:
125 to 128
Medium: X
Sponsoring Org:
National Science Foundation
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