| 摘要 |
A direct conversion receiver having a DC offset eliminating function that eliminates a DC offset component in which an oscillator generates a local frequency signal, A first phase shifter shifts a phase of the local frequency signal from the oscillator by 90°, a first frequency mixer mixes the received radio frequency signal and the local frequency signal from the oscillator, a first low pass filter low-pass filters an output signal of the first frequency mixer, a second phase shifter shifts a phase of the received radio frequency signal by 90°, a second frequency mixer mixes output signals of the first and second phase shifters, a second low pass filter low-pass filters an output signal of the second frequency mixer, a subtracter subtracts an output signal of the second low pass filter, and a DC offset component generated by a direct conversion receiver is eliminated. Accordingly, the receiver prevents a dynamic range of the direct conversion receiver to be narrowed in order to increase a resolution thereof.
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