Digital I/Q imbalance compensation in a quadrature receiver

摘要

An apparatus and method reduce distortion in a processed signal. The apparatus includes a first receive path, a second receive path, a summation unit, and a compensation unit. The first receive path is configured to process a received analog signal into a first digital signal. The second receive path is configured to process the received analog signal with a phase shift into a second digital signal. The summation unit is configured to sum the first and second digital signals to form a processed digital signal. The compensation unit is configured to identify a conjugate of the processed digital signal, apply a weighting factor to the conjugate of the processed digital signal to form a weighted signal, and subtract the weighted signal from the processed digital signal to reduce the distortion.

主权项

1. For use in a wireless communications network, a receiver configured to reduce distortion in a processed signal, the receiver comprising:
a first receive path configured to process a received analog signal into a first digital signal; a second receive path configured to process the received analog signal with a phase shift into a second digital signal; a summation unit configured to sum the first and second digital signals to form a processed digital signal; and a compensation circuit comprising a hardware controller and a weighting module, the compensation circuit configured to:
identify a processed digital signal conjugate from the processed digital signal,apply a set of weighting factors to the processed digital signal conjugate to form a weighted signal by identifying frequency independent distortion for one or more ranges of frequencies in the processed digital signal using a filter bank including one or more filters based on a receiving mode of the receiver and by applying the set of weighting factors to the one or more ranges of frequencies of the processed digital signal conjugate to form a frequency dependent weighted signal as the weighted signal to be subtracted from the process digital signal, andsubtract the weighted signal from the processed digital signal to reduce the distortion.