| 摘要 |
PURPOSE:To prevent the generation of noises owing to the hopping of frequency by varying the transmission state of the spread spectrum signal in response to the state of the information signal. CONSTITUTION:A pseudo noise code is produced from a pseudo noise code generator 2a by a clock signal of a clock signal generator 6 and supplied to a synthesizer 3a. Thus the frequency hops every time the level of said code varies. While an AND circuit 1a keeps its output at a level 0 if the information signal of the level 0 is supplied to a terminal 7. Then the clock signal is supplied to a spread modulating part 4a when the information signal is set at a level 1. As a result, the spread spectrum signal is transmitted continuously when the information signal is set at the level 0 and then transmitted intermittently when the information signal is set at the level 1 respectively. |
