V-Band Six-Port Interferometer Receiver: High Data-Rate Wireless Applications, BER and EVM Analysis, and CFO Compensation

The realization and analysis of an implemented V-band six-port demodulator, operating over 60 GHz band, are presented in this paper. The performance of the design in real-time high-data-rate wireless data transmission is strongly proved using different modulated signals. The valid high data-rate demodulation results achieved over a 7 GHz band (from 57 to 64 GHz), provide a confirmation that this six-port interferometer receiver is an attractive proposition for homodyne or heterodyne transceivers designed for high-speed short-range wireless communication systems, such as future wireless small cell backhaul for 5G. The performance of the proposed direct conversion receiver is characterized in terms of the bit error rate (BER) and error vector magnitude (EVM) for various M-PSK/M-QAM demodulated signals. To verify the resulting data, the relation between the error vector magnitude and the bit error rate is also analyzed. Theoretical results are matched to measured values and validate that the EVM and BER are appropriate metrics for mm-wave channels limited by additive white Gaussian noise. In the last section, the proposed six-port interferometer is introduced for precise estimation of carrier frequency offset (CFO) and Doppler shift in V-band wireless systems. The final results, which include various modulation configurations at mega or Giga symbol rates generated by the implemented transmitter, are supported by laboratory measurements.