摘要 |
Adaptive filter for producing an echo cancellation signal in a transceiver system arranged for digital communication in the duplex mode via one single pair of conductors, the filter comprising delay means (8) having N terminals for delaying the N most recently transmitted symbols, an addressing circuit (10) having M input terminals (M < N), each of which is coupled to the terminals 1 to M of the delay means, the addressing circuit forming from the signals applied to the input terminals an address for a memory (11) in which for each of these addresses always a first correction signal is stored; a weighting and summing arrangement (9) having N input terminals coupled to the N terminals of the delay means, the arrangement providing a second correction signal which is a weighted sum of all the signals at the input terminals thereof, means (12) for adding together the first correction signal and the second correction signal and an adaptive control loop (13). |