SNR Calculation on the basis of channel estimation using Pilot Symbols

Hi,

I wanted to ask how can we calculate SNR on the basis of channel estimation using Pilot Symbols and make CQI table for Adaptive modulation coding according to the estiamted SNR values.

Regards

[KALYAN ACHARJYA]

Being more specific will help in getting a better response.

[Rimsha Javed]

As per my understanding channel estimation alogrithms are implemented at RX side to find the impact of channel like Rayleigh channel on the Received signal. The recevied signal is coorelated with the known pilot signals to find the impact and then equalized to mitigate the chaneel impairments. To find noise , this estimated signals is subtracted from the known pilot signals. Then we find SNR by finding Singal Power and Noise Power, and then CQI table is formed on the basis of this SNR. which paramters should be in consideration while making CQI with SNR threshold.

Please correct me if my concept is wrong.

Answer 1

[charan]

Hi,

Channel estimation is done at the receiver end using pilot signals and based on this estimation the CSI parameters like RI, CQI are calculated. A certain SNR level is mapped to a CQI value when the "BLER" (Block Error Rate) for the link is within acceptable range and the coding scheme is the maximum possible one. The following documentation gives more information about CQI mapping:

https://www.mathworks.com/help/5g/ug/5g-nr-downlink-csi-reporting.html#:~:text=beam%20combining%20coefficients.-,CQI%20Selection,-The%20CQI%20is