Matlab Toolbox : 5G Library : PUCCH Format 1


The Physical Uplink Control Channel (PUCCH) in 5G NR (New Radio) is used to carry uplink control information from the User Equipment (UE) to the gNB (gNodeB, or base station). This control information might include things like HARQ (Hybrid Automatic Repeat reQuest) feedback, SR (Scheduling Request), and CSI (Channel State Information).

In MATLAB's 5G Toolbox, the PUCCH Format 1 refers to a specific format of the PUCCH, and the toolbox provides functions and tools to generate, analyze, and simulate this particular PUCCH format.

PUCCH Format 1 Structure:

PUCCH Format 1 is structured as follows:

  1. Resource Block (RB) Allocation: In this format, a resource block (RB) is allocated in the frequency domain for PUCCH transmission. The exact number of RBs depends on the bandwidth configuration.
  2. Orthogonal Cover Sequence (OCS): The Orthogonal Cover Sequence is used to spread the PUCCH symbols in the time domain. This spreading ensures orthogonality with other sequences and reduces interference.
  3. Modulation and Mapping: The control information bits are modulated using QPSK (Quadrature Phase Shift Keying) modulation in PUCCH Format 1. These modulated symbols are then mapped onto the allocated RBs.

MATLAB 5G Toolbox:

In MATLAB's 5G Toolbox, to work with PUCCH Format 1, you might typically perform the following tasks:

  1. Generation: Generate PUCCH Format 1 signals with specified parameters like bandwidth, OCS, and modulation type. MATLAB provides functions to easily create these signals.
  2. Configuration: Configure parameters such as RB allocation, number of symbols, and modulation scheme.
  3. Simulation: Simulate the transmission and reception of PUCCH Format 1 signals to analyze their performance under various channel conditions. This might involve adding channel impairments like noise, fading, and interference.
  4. Analysis: Use MATLAB's built-in functions and visualization tools to analyze the performance metrics of the PUCCH transmission, such as error rates, throughput, and latency.

Example Code (Simplified):

Here's a very simplified MATLAB code snippet that demonstrates how you might generate a PUCCH Format 1 signal using MATLAB's 5G Toolbox:

matlabCopy code% Initialize parameters
N_RB = 10; % Number of resource blocks
OCS = [1 0 1 0]; % Orthogonal Cover Sequence
modulationScheme = 'QPSK';

% Generate PUCCH Format 1 signal
[pucchSymbols, info] = ltePUCCH1(N_RB, OCS, modulationScheme);

% Plot the PUCCH symbols
figure;
stem(real(pucchSymbols)); hold on;
stem(imag(pucchSymbols), 'r'); hold off;
title('PUCCH Format 1 Symbols');
xlabel('Sample Index');
ylabel('Amplitude');
legend('Real', 'Imaginary');

This is a very basic example, and in a real-world scenario, you would include more configurations, parameters, and analyses. The MATLAB 5G Toolbox provides comprehensive functions and tools to work with various 5G NR features, including PUCCH Format 1.