| 摘要 |
PURPOSE:To attain the synchronizing demodulation with a simple circuit constitution by modulating directly the phase of a pseudo noise PN code with an information signal. CONSTITUTION:A clock generator 1 is provided together with a PN code generator 2, variable delay circuit 3, correlator 4, loop filter 5, voltage control oscillator 6, PN code generator 7, and a waveform shaping circuit 8. A modulator consists of only the generator 1, the generator 2, and the circuit 3. Then a PN signal. is inputted to the circuit 3 and the delay time is changed by an information signal. Then the phase modulation is applied to a PN code. Thus the primary demodulation can be omitted and it is possible to attain the synchronizing demodulation that is hitherto difficult to perform in a system where the PN code is turned on and off. |
