| 摘要 |
PURPOSE:To eliminate the discontinuation of the phase at the switching point of the input data and then increase the reliability, by securing f1=(n-1)B and f2=nB (n>= integer of 2; B: modulating speed) each and at the same time securing the synchronization with the signal of frequency fs=B. CONSTITUTION:If modulating speed B=1,200 Baud and integer n=2 are set each, the signals (f), (c) and (d) having the frequencies fs=B=1,200Hz, f1=(n-1)B= 1,200Hz and f2=nB=2,400Hz each are delivered from signal generating circuit 4. In this case, signals (c) and (d) are synchronized with signal (f). Then input data (a) is synchronized with signal (f) having frequency fs at synchronizing circuit 5 to be formed like signal (e). Thus this signal (e) is modulated at modulating circuit 3 and by signals (c) and (d) to obtain FSK modulation signal (b). In this case, the synchronization is secured perfectly among data (a), signal (c) and signal (d) each. Thus the phase discontinuation which occurs hitherto is never caused to signal (b). |
