| 摘要 |
PURPOSE:To simplify a circuit constitution, and to widely reduce cost by eliminating the need for a pull-in circuit and a synchronism hold circuit, etc., constituted of a clock reproducing circuit, a diffused code generation circuit and a loop which are an essential constituting condition in inverse diffusion up to this time. CONSTITUTION:A demodulating part 20 inputs a spread spectrum signal and separates it into a first and a second diffusing signals corresponding to a first and a second carrier waves by a comb-line filter 24. Both are multiplied by a multiplier 6 and after the obtained multiplied output signal is separated into two signals corresponding to the frequencies of the difference and the sum of the first and the second carrier waves, both are multiplied by the multiplier 9, and two squared output signals corresponding respectively to the double frequencies of the first and the second carrier waves are obtained and after they are separated, they are frequency-divided by 1/2-frequency dividers 25, 26 respectively, and a first and a second regenerated carrier waves are obtained. The multiplier 7 multiplies the second regenerated carrier wave and the second diffused signal and generates a regenerated diffused code signal. The multiplier 8 multiplies this signal and the first regenerated carrier wave and generates an inverse diffusing signal. The multiplier 5 multiplies this signal and the first diffused signal, and the inverse diffusion is performed. A primary modulated wave signal is demodulated and an information signal is outputted. |
