| 摘要 |
PURPOSE:To provide the echo adding circuit which can generates an echo signal having a small noise component even when a companding process is performed. CONSTITUTION:This circuit is equipped with a cyclic loop which consists of a compressing conversion circuit 2 generating a logarithmically compressed signal C from a source signal A, a waveform composing circuit 1, a low-pass filter 3, a delay circuit 4, a low-pass filter 5, and an attenuator 7 and generates a delayed signal D from the signal C and an expanding conversion circuit 6 which generates the uncompressed echo signal E from the signal D. The compressing conversion circuit 2 and expanding conversion part 6 are not included in the cyclic loop, so noises which are generated there are not integrated by remaining in the loop. |
