| 摘要 |
<p>PROBLEM TO BE SOLVED: To obtain a digital demodulator where the number of parts is minimum and that can be operated without adjustment. SOLUTION: A loop filter 2 receives a multiplexed signal at an input terminal of a 1st CORDIC 1, an output signal of an accumulator 4 at its phase input terminal, and an output signal not assigned to the same coordinate as an amplitude input terminal in use, a 1st multiplex stage 3 multiplexes an output signal on a frequency selection signal denoting a pilot nominal frequency and an input terminal of the accumulator 4 receives the output signal from the 1st multiplex stage 3. One amplitude input terminal of the accumulator of a 2nd CORDIC 7 receives the output signal from a multiplier 5, an input terminal of the multiplier receives the output signal from the accumulator 4, multiplies '2' with it and an output terminal of the 2nd CORDIC 7 gives a demodulated difference acoustic signal.</p> |
