| 摘要 |
PROBLEM TO BE SOLVED: To solve such an inconvenience that a conventional FSK modulator is required to use an extension coil, a switching voltage generation circuit, and an element such as a variable capacity diode, and thus a cost is increased. SOLUTION: In the FSK modulator comprising an SAW resonator having two vibrational states, and an amplifier; the SAW resonator having two vibrational states can obtain the two vibrational states by arranging first and second 1-port type SAW resonators in parallel, in which one IDT and a pair of reflectors are arranged at both sides thereof. An SW and a current limiting element are serially connected, and then grounded to an output terminal of the second SAW resonator by using the first SAW resonator as a drive means and the second SAW resonator as a control means. The output terminal of the first SAW resonator is connected to the input terminal of the amplifier. The output of the amplifier is connected to the input terminal of the first and second SAW resonators after letting a phase convertor pass. COPYRIGHT: (C)2007,JPO&INPIT
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