Method for implementing predistortion compensation processing for 5G NR in-band modulated signals

A method for implementing predistortion compensation processing for a 5G NR in-band modulated signal, the method comprises the steps of:

• (1) first configuring a wideband modulator to output continuous wave signals enabling an output frequency interval of switching signals to be consistent with a bandwidth of a 5G NR subcarrier, and recording a power value Pn of the output continuous wave signal of a modulation channel corresponding to a current frequency through a power meter, the 5G NR subcarrier bandwidths are configured as 15 kHz, 30 kHz, and 60 kHz;
• then
• (2) calculating power measurement difference values of all points and P0 according-to the power value Pn, taking P0 as a reference point, P0 measured by the power meter, normalizing, and generating a compensation channel impulse response through forming filtering;
• (3) performing inverse Fourier transform on the compensation channel impulse response and converting the compensation channel impulse response into a time domain based power compensation factor;
• (4) carrying out inverse Fourier transform on original baseband signals generated by the 5G NR subcarrier according to different symbols to generate I and Q two paths of baseband signals;
• (5) multiplying the power compensation factor by the I and Q two paths of baseband signals point by point to generate compensated baseband data;
• and
• (6) filtering the generated compensated baseband data with a root raised cosine filter with a roll-off coefficient of 0.22, performing digital-to-analog conversion to generate an analog zero intermediate frequency signal, and inputting the analog zero intermediate frequency signal into a broadband demodulator to perform frequency conversion modulation on the 5G NR broadband signal.