| 摘要 |
PROBLEM TO BE SOLVED: To provide a high frequency amplifier whose measurement accuracy is improved more by determining the gain of the high frequency amplifier so as to maximize the SNR value of a GPS receiver, and the GPS receiver using the high frequency amplifier. SOLUTION: An operational amplifier IC1 is a chip component made in an integrated circuit, a resistor R1 terminates a low-pass filter provided in an RF part and also determines the gain of the operational amplifier IC1 in cooperation with a feedback resistor R5, and resistors R3 and R4 sets the bias of the positive input terminal of the operational amplifier IC1. A capacitor C1 cuts dc components in a received signal outputted by the low-pass filter 8, and a capacitor C2 is a bypass capacitor for lowering the high frequency impedance. To maximize the SNR value, the following setting is made: the resistor R1=1.8 kΩ, the resistor R3=8.2 kΩ, the resistor R4=6.8 kΩ, the capacitor C1=0.1μF, the capacitor C2=1,000 pF, and the feedback resistor R5=2.1 kΩ. COPYRIGHT: (C)2005,JPO&NCIPI
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