ADVANCED RECEIVER ARCHITECTURES IN RADIO-FREQUENCY APPLICATIONS

Abstract

The general principles of several types of receivers fall under the two main headings of TRF (tuned radiofrequency) receivers, where the received signal is processed at the incoming frequency right up to the detector stage, and thesuperhet (supersonic heterodyne) receiver, where the incoming signal is translated (sometimes after some amplification atthe incoming frequency) to an intermediate frequency for further processing. There are however, a number of variants ofeach of these two main types. Regeneration (‘reaction’ or ‘tickling’) may be applied in a TRF receiver, to increase both itssensitivity and selectivity. This may be carried to the stage where the RF amplifier actually oscillates – either continuously,so that the receiver operates as a synchrodyne or homodyne, or intermittently, so that the receiver operates as a superregenerativereceiver, both of which have been described previously. The synchrodyne or homodyne may be consideredalternatively as a superhet, where the IF (intermediate frequency) is 0 Hz. In this paper we present the new type of receiverarchitectures which work in radiofrequencies.Keywords: Supersonic Heterodyne, Tuned Radio Frequency.