CSI of the guard-band subcarrier in 5G channel

my ultimate goal is to use 5G toolbox to estimate the compete channel response (for in-band subcarriers & guard-band subcarrier).

This can be done as follows

1. Generate 20 MHz signal
2. Use of an array with Nt antennas at TX
3. Perform perfect channel estimation

I can use the following link to generate 20 MHz signal. But not sure how to check the number of subcarriers or IFFT point

https://www.mathworks.com/help/5g/ug/5g-nr-tm-waveform-generation.html

The following link perform perfect channel estimation. But I have question why the number of subcarriers in the channel magnitude response is limited to 300? what about the rest of subcarriers

https://www.mathworks.com/help/5g/ref/nrperfectchannelestimate.html#mw_function_nrPerfectChannelEstimate_sep_mw_3cbeae39-cf8f-4ffc-8cd5-1049e2c6108b

Is it possible to use 5G toolbox to estimate the compete channel response (for in-band subcarriers & guard-band subcarrier)?

Answer 1

[vidyesh]

Hi Abdelwahab,

I see that you're seeking clarification on how the number of subcarriers is determined, specifically why there are 300 subcarriers in the 'NR Perfect Channel Estimate' example.

The number of subcarriers in a given bandwidth is determined by the number of Resource Blocks allocated, which is specified by the input parameter `NSizeGrid`. In the "Perfect channel estimate" example, the number of RBs, denoted as `NRB`, is set to 25. Given that each Resource Block comprises 12 subcarriers, multiplying the two gives us the total number of subcarriers: 25 RBs × 12 subcarriers/RB = 300 subcarriers. For further information, you can refer to the following documentation page: https://www.mathworks.com/help/5g/ref/nrperfectchannelestimate

Guard bands are intentionally designated frequency spaces that remain unoccupied; they serve as protective margins between adjacent frequency channels or bands. Their primary purpose is to prevent signal interference, which helps to maintain the integrity and quality of communications. Because no signal is transmitted over these guard bands, they are not included in the signal estimation process.

For a detailed explanation of NR frequency ranges and the role of guard bands, the following page will be useful:

https://www.sharetechnote.com/html/5G/5G_FR_Bandwidth.html

Hope this helps.