| 摘要 |
A multi-rated delay multiplexing direct spread spectrum communication system the multiplicity of which can be changed. The system performs control operation as quickly as possible by suppressing the output fluctuation within a narrow range so as to perform constant power transmission. A gain-variable amplifier (21) is provided at the succeeding stage of a modulator (19) and the gain of the amplifier (21) is controlled by a control signal generated based on the detection signal of the output of a power amplifying section (23). A detecting and control section (21c) detects the RF output of a delay multiplexing spread signal by means of a diode, finds the average power by means of an integrator, and equalizes the output of the amplifier (21) to a comparation voltage by means of a control signal which is generated on comparing the average power with the comparation voltage. However, when the output of the amplifier (21) is equalized to the comparation voltage, the time constant of the integration performed by the section (21c) is kept small for a fixed period of time by using a control signal representing a simplex/multiplex part. Consequently, a multiplexing switching section can quickly control the power. <IMAGE> |
