| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a data receiver with a gain control circuit simply configured to perform level adjustment without D/A conversion. <P>SOLUTION: This data receiver is provided with a gain control means 61 for controlling a gain of an input signal, an orthogonal detecting means for orthogonally detecting the gain controlled signal and dividing the signal into a vector component A<SB>x</SB>and a vector component A<SB>y</SB>, A/D conversion means 63, 612 for sampling the vector components A<SB>x</SB>and A<SB>y</SB>, an absolute value calculating means for calculating an absolute value of sampled data, a reference value generating means for generating a reference value, a subtracting means for subtracting the reference value from the absolute value outputted by the absolute value calculating means, a shift register, a selecting means for selecting an output signal of the subtracting means that enters the shift register, and a low-pass filter for smoothing an output of the shift register. An output voltage from the low-pass filter is compared to a reference voltage to control the gain of the gain control means, and the vector size of the input signal can be adjusted to "1" by a simple circuit. <P>COPYRIGHT: (C)2005,JPO&NCIPI |
