LS and LMMSE Channel Estimation and Equalization in NR PDSCH Throughput MATLAB Example

I'm currently working with MATLAB's NR PDSCH Throughput example and have modified the setup to use 8x2 MIMO and disabled HARQ processes. Now, I'm aiming to evaluate and plot BER vs SNR for two different receiver configurations:

1. LS estimation + LS equalization
2. LMMSE estimation + LMMSE equalization

However, the default example uses the nrChannelEstimate function for channel estimation, which, upon inspection, appears to perform LS estimation. At the same time, the equalization step in the code is done using nrEqualizeMMSE, which doesn't align with the LS-based chain I'm trying to evaluate.

Could someone help me understand:

• What exactly is happening inside nrChannelEstimate?
• How can I modify the code to perform LS estimation + LS equalization and LMMSE estimation + LMMSE equalization independently for comparison?
• Can nrChannelEstimate be configured or used with mentioning options for using LS or MMSE based Estimation

Frequency Offset Correction

Additionally, the example handles timing offset correction using:

[rxWaveform, ofdmResponse, timingOffset] = channel(txWaveform, carrier);

But at high Doppler values, we expect significant frequency offset too. From my understanding, the current setup does not correct frequency offset explicitly.

• Does the timing offset output also account for frequency offset correction in this function?
• If not, how should I introduce frequency synchronization in the receiver chain?

One thing I’ve noticed is that in the LTE Toolbox, there are dedicated functions like lteFrequencyOffset and lteFrequencyCorrect to estimate and correct for frequency offset. However, I couldn’t find any equivalent functions in the 5G Toolbox (to my knowledge). Is there any recommended approach or workaround to handle this in the 5G NR framework or can we use same LTE toolbox based function with this chain?

Any guidance or suggestions would be greatly appreciated!

Thanks in advance.