Direct conversion radio receiver

摘要

A receiver (54) comprising an input for receiving an RF signal (Figure 7) centered at a first frequency and having a bandwidth. The receiver also comprises a first mixer (62) for producing a first output signal. The first output signal results from mixing the RF signal with a signal having an energy spreading portion (p(t)) and a down-converting portion (c(t)). Moreover, this first output signal comprises a self-mixing DC signal (c(t)p(t) self-mixing DC component) and a down-converted and energy spread RF signal (Figure 11) . The receiver further comprises a second mixer (70) for producing a second output signal by mixing a signal responsive to the first output signal with the energy spreading portion of the signal. The second output signal comprises two signals, namely: (1) a baseband signal (down-converted RFAI) responsive to the down-converted and energy spread RF signal; and (2) a portion of the spread DC signal (spread DC).