| 摘要 |
PROBLEM TO BE SOLVED: To provide a transmitter loaded on a satellite switchable to optimum transmission power by itself. SOLUTION: Output is performed to a judgement part 7 as the error voltage (a) of a phase locked loop 1 and transmission power control signals (b) are outputted to a control part 9 in the judgement part 7. The reception level of up-link signals is outputted from an AGC detection part 6 as an AGC control voltage (c). In the judgement part 8, based on the level judged result of the AGC control voltage (c) and bit rate selection information (h), the request value (d) of transmission power capable of securing a line margin is outputted to the control part 9. In the control part 9, the output of the judgement part 7 and 8 is compared, the transmission power is decided, and simultaneously, in the case that the request value of the judgement part 8 can not be satisfied, the selection control signals (f) of a highest bit rate capable of maintaining a line by the transmission power are outputted to a data processing part 10. In a transmission part 30, down-link carrier waves are modulated by base band signals outputted from the data processing part 10 in a modulator 11 and they are transmitted as RF signals after power amplification 12. |
