Frequency translational RF receiver with time varying transmission lines (TVTL)

Abstract

A novel receiver architecture based on frequency translation is proposed in this paper. The receiver treats a mono-lithically integrated time-varying transmission line (TVTL) as a capacitive mixer with minimum insertion loss and noise penalty, placing it in the first stage before a fixed, narrow bandpass filter. By varying the LO/carrier frequency of the TVTL mixer, the complete received frequency band is shifted so that the desired band can be selected with a fixed bandpass filter, without suffering signal-to-noise ratio (SNR) degradation that usually occurs in a conventional heterodyne receiver with a mixer at its first stage. Measured results of both the TVTL MMIC and the testbed of the frequency translational receiver validate the proposed concept and confirm its potential for applications in software defined radios.