| 摘要 |
PURPOSE:To increase the spectrum resolution of a discrete Fourier conversion and then signal enhance the time property of a receiver, by resetting the counter when the input arrives and ends each. CONSTITUTION:The input PCM signal is applied to the multiplier 10 and the power detecting circuit 2. When the input signal more than the prescribed power is detected at the circuit 2, the output is applied to the D-FF3 and 4. The Q outputs of the FF3 and 4 reset the counter 7 for coefficient ROM address via the exclusive OR gate 5 and the inverter 6. As a result, the contents of the coefficient ROM8 is given to the multiplier 10 after the parallel-serial conversion 9 and then multiplied by the input PCM signal to be supplied to the totalizing circuit of discrete Fourier conversion via the terminal 11. Accordingly, an operation is started for the discrete Fourier conversion immediately after the arrival and end of the input signal. |
