Patent ID: 8249538
Filing Date: 2012-08-21
Classification: H04B

Abstract:
1. A method comprising: receiving a wireless signal; selecting an initial value of a baseband offset frequency; measuring an initial noise level of downconversion of the received wireless signal to the initial value of the baseband offset frequency; incrementing the initial value for the baseband offset frequency to select a new value of the baseband offset frequency; measuring a new noise level of downconversion of the received wireless signal to the new value of the baseband offset frequency; selecting the initial value of the baseband offset frequency as a selected baseband offset frequency value if the initial noise level is lower than the new noise level; selecting the new value of the baseband offset frequency as the selected baseband offset frequency if the new noise level is lower than the initial noise level; directly downconverting and demodulating the received wireless signal to the selected baseband offset frequency value that is offset from zero frequency to produce an in-phase (I) baseband offset signal centered at the baseband offset frequency value and a quadrature-phase (Q) baseband offset signal centered at the baseband offset frequency value; bandpass filtering the I baseband offset signal and Q baseband offset signal to produce an I bandpass signal and a Q bandpass signal, respectively; and downconverting the I bandpass signal and the Q bandpass signal from the baseband offset frequency to zero frequency to produce an I baseband receive signal and a Q baseband receive signal.