| 摘要 |
PURPOSE:To manufacture of transmitter in advance before an installed location and frequency assignment are decided by setting the center frequency of the transmitter by the program input, providing a reference oscillator corresponding to the offset frequency and selecting the reference oscillator in response to the condition of a base station. CONSTITUTION:The transmission frequency f0 is set by inputting a frequency division ratio M of a programmable frequency division section 18 from an input section. In this case, one channel is assigned to one area and the frequency division ratio M corresponding to the assigned channel is inputted and set. For example, if it is decided that the transmitter installed to the peripheral base station sends a signal in an offset frequency higher than the center frequency f0 by +alpha, a switch section 13 selects a reference oscillator 10. Then the output of the voltage control oscillation section is changed so that the output of the programmable frequency division section 18 in the entire synthesizer 19 approaches the reference frequency signal. As a result, the frequency outputted from a voltage controlled oscillation section 17 becomes an offset frequency of f0+alpha. |
