Generating LTE signal using Matlab

I want to generate LTE signal with sampling rate of 122.88MSPS for testing using AD9371 Evalution board using ZC706 zynq board & IIO Scope.

First I  generated LTE test signal using LTE Downlink Generator App in matlab & then upsampled to get 122.88MHz. After uploading that file in DAC Buffer in IIO scope, i was getting little different waveform than ideal.  

I have written matlab code for upsampling as

sig_out = resample(x, 4, 1);

>> db_backoff = 3;

>> QAM64_20MHz = tmwaveform * (10^(-db_backoff/20))/max([max(real(tmwaveform)) abs(min(real(tmwaveform))) max(imag(tmwaveform)) abs(min(imag(tmwaveform)))]);

Pls suggest

Pls suggest what to do toget ideal waveform.