An adaptive FIR echo canceller in analog full-duplex speech scrambling system

The purpose of this paper is to focus on the local echo-cancelling problem of full-duplex scrambled speech communications over two-wire telephone networks. We propose a new adaptive FIR filter algorithm for echo cancellation in such applications. The proposed algorithm differs from the conventional one by the construction of input signals in an optimal way using the D-optimal experiment design. The advantage in using the proposed adaptive FIR echo canceller is demonstrated through simulation results.