| 摘要 |
PURPOSE:To ensure the superposition for an optional waveform with an optional size and to obtain a superposition data in an easy way, by using an FM modulator for the modulation of the superposition data and feeding the comparison frequency and the local frequency obtained from the output of the FM modulator to an FSK modulator. CONSTITUTION:The input data of a data input terminal 12 is turned into a double superposition data compared with the transmission frequency through a synchronism reproducing circuit 8. This superposition data is fed to a phase shifter 9 to be controlled to the prescribed phase relation. The output of the shifter 9 undergoes the FM modulation through an FM modulator 10, and the output frequency of the modulator 10 is varied from (carrier frequency fc - maximum frequency deviation DELTAf) through (fc+DELTAf). The output of the VCO1 of the PLL constitution undergoes the conversion of frequency through a mixer 2 and by the output of the modulator 10. The output is then divided by a variable divider 3 having different ratios of division is accordance with the input data and then fed to a phase detector 4 to be compared with the reference signal of the output of the modulator 10 in terms of the phase. Then the output of the VCO1 is controlled, and an optional waveform is superposed in an optional size via an output divider 6 and a BPF7. Then a data is delivered. |
