  5G New Radio (NR) introduces new flexibility that different numerologies can
be selected to meet the requirements of a wide variety of services. For this
new structure, blind numerology identification can increase system efficiency.
Therefore, we propose a blind identification method for mixed numerologies. An
autocorrelation method is applied in the time domain by correlating the cyclic
prefix (CP) signal of the candidate numerology in the received composite signal
for numerology type identification. Then, the location of each numerology in
the frequency domain is identified by the variance difference in the power
spectral density (PSD) of the subbands, on which different numerologies are
occupied. The simulation results are obtained under additive white Gaussian
noise (AWGN) and frequencyselective channels. The obtained results show that
the proposed method has a robust identification accuracy and a satisfactory BER
performance as compared to the non-blind identification approach in the
conventional mixed-numerology system.
