An Out-of-Band Spectrum Suppression Technique for Frequency Division Duplexing Communication Systems

The conventional full-band (FB) digital predistortion (DPD) method could be ineffective in frequency division duplexing (FDD) communication systems, particularly when power amplifiers (PAs) are driven into the near-saturation region. This letter introduces an out-of-band (OOB) spectrum suppression technique with an anti-aliasing architecture to mitigate the spectrum spreading effect of PAs. The proposed anti-aliasing architecture significantly reduces computational complexity compared to existing methods. The experimental results show that the proposed method achieves better ACPR performance than existing methods, while it reduces the computational complexity by approximately 80%.