A fast response digital logic tone detector

Digital logic tone detector (DLTD) based on Teager´s energy tracker is presented. We show that the circuit can detect the offset tone between the input and the local oscillator frequency. Also we investigate the possibility of detection bandwidth control by adding a RC integrator. Proposed circuit consists of conventional digital logic devices without analog elements. As a consequence, it is well suited for integrated circuit realizations and has superior reliabilities over component drift or aging effect. Moreover it has fast response time and accurate discrimination characteristics