A hardware architecture for time reversal of short impulses based on frequency domain approach

Abstract

In this paper, a compact and low-cost electronic circuit system is designed to time reverse short impulses in microwave regime. The proposed system consists of three major parts: (i) Fourier transform, to obtain discrete spectra of input impulses; (ii) Digital signal processing, to digitize spectral samples resulted from the first part and process them; and finally (iii) Inverse Fourier transform, to synthesize time-reversed impulses using discrete continuous wave elements. This architecture is composed of commercially available semi-conductor components, including oscillators, multipliers/mixers, band-pass-filters, amplifiers, and switches. Thus, it can embody a system-on-chip implementation of real-time time-reversal. Its performance is demonstrated by Advanced Design System simulations, with time-reversal of impulses with around 1.4 ns temporal width and [22, 29] GHz spectral coverage in noisy environments as examples.

Full Analog Broadband Time-Reversal Module for Ultra-Wideband Communication System

“…The former method can directly sample, store and reverse the temporal signal; or temporal signal TR operation is realized by Fourier transform and frequency domain phase conjugate. The inversion of the signal in the time domain is equivalent to phase conjugate transformation of each frequency component in the frequency domain [10]- [12].Therefore, the temporal signal is transformed into the frequency domain by Fourier transform, the phase conjugate processing is performed on the signal in the frequency domain, and the TR signal can be obtained by inverse Fourier transform [13], [14]. The above analog methods cannot handle general aperiodic signals, and have poor real-time performance.…”