Using hNRReferen​ceWaveform​Generator with TDD actual pattern

Hi Matlab,

3GPP UL waveforms when generated from 5G Toolboxes, fill only slots which is defined from 3GPP. we also need special subframe with 4 symbols UL enabled. Let me know if we can fill special subrame when exact UL symbols.

// Matlab outputs :

hNRReferenceWaveformGenerator(ulnrref,bw,scs,dm,ncellid);

G-FR1-A1-5, 100MHz, 30kHz, TDD, 1

ulrefwaveformgen.Config.PUSCH{1, 1}.SymbolAllocation = [0,14]

ulrefwaveformgen.Config.PUSCH{1, 1}.SlotAllocation = [8,9,18,19]

// 3GPP defined TDD pattern.

38.141 : Table 4.9.2.2-1: Configurations of TDD for BS type 1-C and BS type 1-H test models

Field name Value

referenceSubcarrierSpacing (kHz) 15 30 60

Periodicity (ms) for dl-UL-TransmissionPeriodicity 5 5 5

nrofDownlinkSlots 3 7 14

nrofDownlinkSymbols 10 6 12

nrofUplinkSlots 1 2 4

nrofUplinkSymbols 2 4 8

Answer 1

[Shubham]

Hi Madhusoodan,

To incorporate special subframes with 4 uplink symbols in a 5G NR TDD configuration using MATLAB's 5G Toolbox, you'll need to customize the TDD pattern to accommodate the specific requirement of having a special subframe. The 5G Toolbox provides flexibility in configuring the TDD pattern, but it requires manual adjustments to the slot and symbol allocation.

Here's a step-by-step approach to achieve this:

Step 1: Understand the TDD Pattern

The TDD pattern is defined by a combination of downlink slots, uplink slots, and special subframes. The special subframes can include a mix of downlink, guard, and uplink symbols. In your case, you want a special subframe with 4 uplink symbols.

Step 2: Customize the TDD Configuration

You will need to adjust the SymbolAllocation and SlotAllocation properties in the configuration to reflect your desired TDD pattern.

Step 3: Modify the MATLAB Configuration

Here's how you can modify the configuration to include a special subframe with 4 uplink symbols:

% Define the uplink reference waveform configuration
ulnrref = 'G-FR1-A1-5';
bw = 100; % Bandwidth in MHz
scs = 30; % Subcarrier spacing in kHz
dm = 'TDD'; % Duplex mode
ncellid = 1; % Cell ID

% Generate the reference waveform
ulrefwaveformgen = hNRReferenceWaveformGenerator(ulnrref, bw, scs, dm, ncellid);

% Modify the PUSCH configuration to include special subframe
% Assuming you want the special subframe in the 10th slot
ulrefwaveformgen.Config.PUSCH{1, 1}.SymbolAllocation = [0, 14]; % Full slot allocation
ulrefwaveformgen.Config.PUSCH{1, 1}.SlotAllocation = [8, 9, 18, 19]; % Example slot allocation

% Add a special subframe with 4 uplink symbols
specialSlotIndex = 10; % Define the slot index for the special subframe
specialSymbolAllocation = [10, 4]; % Start at symbol 10, with 4 uplink symbols

% Update the configuration for the special subframe
ulrefwaveformgen.Config.PUSCH{1, 2}.SymbolAllocation = specialSymbolAllocation;
ulrefwaveformgen.Config.PUSCH{1, 2}.SlotAllocation = specialSlotIndex;

% Generate the waveform
[ulWaveform, ulInfo] = ulrefwaveformgen();

% Display the configuration
disp(ulrefwaveformgen.Config);

Key Points:

• You specify which slots are used for uplink transmissions. The SlotAllocation array determines which slots are allocated for uplink within the TDD frame.
• The SymbolAllocation specifies which symbols within a slot are used for uplink. For the special subframe, you set this to start at a specific symbol and include the desired number of uplink symbols.
• The 5G Toolbox allows for significant customization of TDD patterns, but the specific pattern must comply with the overall TDD configuration rules.

[Madhusoodan NA]

Thanks a lot for the answer. I am able to get required waveform now.