摘要 |
Signal processing for a receiver, such as a radio receiver within a cellular telephone, includes providing frequency conversion, preferentially passing a desired signal following the conversion, and introducing both phase-based filtering and equalization to the band-filtered signal. In one embodiment, the band filtering is provided by a low pass filter and the compensation occurs following operations by a polyphase filter, which implements the phase-based filtering. In many applications, the frequency conversion is a down conversion to either a zero intermediate frequency or a low intermediate frequency. The low pass filter reduces out-of-band interference and blocking signal strength, but may introduce phase-related distortions. The polyphase filtering and equalization cooperate to control the phase-related distortions.
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