| 摘要 |
PURPOSE:To obtain a synthesizer which can be used even for a multiband multichannel receiver by composing a reference divider of a programable divider whose dividing ratio can be set and by making it possible to set a reference frequency to a channel space. CONSTITUTION:This synthesizer is provided with reference oscilator 1, reference programable divider 9, reference frequency switching method 11 and the time of band switching, position comparator 3, LPFs 4-1 and 4-2, programable divider 5, dividing-ratio setting method 8, and voltage control oscillators 6-1 and 6-2. All of or some of reference dividers obtaining reference frequencies are composed of programable dividers 9 and 5 which are able to set their dividing ratios by switching method 11 and setting method 8 in order to change its dividing ratio, and the reference frequency at the time of band switching is switched by switching method 11, and the outputs of LPEs 4-1 and 4-2, and the outputs of oscillators 6-1 and 6-2 are switched simultaneously by change-over switches 12 and 13. |
