摘要 |
A direct conversion receiver includes a mixer for converting an RF signal into a baseband signal, a dynamic DC offset compensator for compensating for a dynamic DC offset caused by the effect of second order nonlinear distortion of the mixer on an interfering wave that enters the input terminals of the mixer, and a static DC offset compensator for compensating for a static DC offset caused by self-mixing of a local signal and a leakage component of the local signal that appears at the input terminals of the mixer. The static DC offset compensation starts at a time t 1 after a DC offset compensation operation has started. The static DC offset compensation is finished at the next time t 2 , and then the dynamic DC offset compensation starts. The dynamic DC offset compensation is finished at the next time t 3 . With this configuration, only a change in DC offset due to the dynamic DC offset is compensated after compensating for the static DC offset component. The dynamic DC offset compensator does not have an element for storing the magnitude of the static DC offset.
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