MATLAB: How to generate LTE15 PRACH subframes

lteLTE Toolboxlte15prachrachresampling

Hi experts,

I am trying generate LTE15 (NULRB = 75) PRACH format 0 subframes. The expected subframe length is 23040 samples but ltePRACH() yields subframes of length 30720.

Is there anyway to get the correct subframe length from the LTE Toolbox without custom code for resampling?

Thank you very much.

Best Answer

Hello Reza,

It is not possible to directly generate the waveform at a different sampling rate, but it should be very easy to perform resampling using the MATLAB resample() function as follows:

>> ue.NULRB = 75;
>> prach.Format = 0;
>> waveform = ltePRACH(ue,prach);
>> waveform = resample(waveform,23040,30720);
>> size(waveform)
ans =
       23040           1

For information, the reason we use 30.72 Ms/s is for compatibility with our normal uplink waveforms created using lteSCFDMAModulate.

Regards,

Iain.

Related Solutions

MATLAB: 5G NR Downlink Carrier Waveform Generation

Hi Javier,

You can provide any values. But the best guide to run different simulations is the Transmission bandwidth configurations provided in the standard spec of TS 38.104 Section 5.3.2.

For example to configure a value of Channel Bandwidth of 30 MHz of 15 kHz SCS and 50 MHz bandwidth of 60 kHz SCS, make the following updates to carrier structure and bwp structure:

% Carriers Configuration
carriers = [];
carriers(1).SubcarrierSpacing = 15; % 15 kHz
carriers(1).NRB = 160;  % 160 resource blocks comprise 30 MHz bandwidth
carriers(1).RBStart = 0;
carriers(2).SubcarrierSpacing = 60; % 60 kHz
carriers(2).NRB = 65;    % 65 resource blocks comprise to 50 MHz bandwidth
carriers(2).RBStart = 0;
% Bandwidth parts configuration (Occupying complete carrier for both numerologies)
bwp = [];
bwp(1).SubcarrierSpacing = carriers(1).SubcarrierSpacing;          % BWP Subcarrier Spacing same as carrier subcarrier spacing 1
bwp(1).CyclicPrefix = 'Normal';         % BWP Cyclic prefix for 15 kHz
bwp(1).NRB = carriers(1).NRB;                        % Size of BWP

bwp(1).RBOffset = 0;                   % Position of BWP in SCS carrier

bwp(2).SubcarrierSpacing = carriers(2).SubcarrierSpacing;          % BWP Subcarrier Spacing
bwp(2).CyclicPrefix = 'Normal';         % BWP Cyclic prefix for 60 kHz
bwp(2).NRB = carriers(2).NRB;                        % Size of BWP
bwp(2).RBOffset = 0;                   % Position of BWP in SCS carrier

This will generate the output waveform for both the numerologies.

Hope this helps.

Regards,

Sriram

MATLAB: How to buy LTE toolbox

Hi,

You can reach out to the sales team from this link : Contact Sales.

Best Answer

Related Solutions

MATLAB: 5G NR Downlink Carrier Waveform Generation

MATLAB: How to buy LTE toolbox

Related Question