An Electronic Hybrid with Adaptive Balancing for Telephony
David G. Messerschmitt · IEEE Transactions on Communications · 1980
A new form of adaptive balancing hybrid is proposed for application to the two-wire to four-wire interface of a local digital switch. It is similar to an echo canceller but with a single degree of freedom and much simpler circuitry. In this paper a theory of operation of the hybrid is developed, and in a companion paper two circuit implementations and experimental results are reported.