OCBPSR: Orthogonal Complex BandPass Sampling Receiver

Second-order/Complex BandPass Sampling Receivers (CBPSR) are attractive for acquiring multi-signals for SDR/CR applications. One of the issues caused by the implementation of such receivers is the signals IQ mismatch. This paper proposes a CBPSR implementation that eliminates this IQ mismatch by reformatting the received signals in an orthogonal analytic form (thus named OCBPSR). Our implementation will also reduce the required sampling frequency to below the Nyquist rate, and so reducing the processing time to recover the signals. This is achieved by folding the upper-side of the received signals to the same fold-frequency in the baseband domain without overlapping, by making the signals orthogonal. MATLAB simulation is used to evaluate the performance of our OCBPSR using various scenarios of harsh signal environment, including Doppler and multipath effects.