How to characterize PA for DPD implementation with or without hardware ?

For implememting DPD for our Power amplifier,We need input/output data file of the PA to characterize it.

How can we get that data of PA with hardware using VST or without hardware by simulating our PA according to its specifiacations ?

Answer 1

[Balavignesh]

Hi Utkarsh,

Implementing Digital Pre-Distortion (DPD) for your Power Amplifier (PA) requires characterizing the PA using input/output data.

Steps to obtain Data with Hardware using VST:

1. Setup: Connect your 'PA' to a Vector Signal Transceiver (VST). The VST acts as both a signal generator (to provide the input signal to the PA) and a signal analyzer (to capture the output from the PA).
2. Data Acquisition: MATLAB's Instrument Control Toolbox provides functions to communicate with the hardware. You could generate a test signal in MATLAB, send it to 'PA' through a 'VST', and finally capture the output signal using a 'VST' https://www.mathworks.com/help/instrument/
3. Save Data: Save the input and output signals into a file for further analysis and DPD model development.

% Assuming you have the necessary toolboxes and drivers installed
vst = vstInit('IPAddress', '192.168.1.100'); % Initialize VST with its IP
inputSignal = generateTestSignal(); % Custom function to generate your test signal
vst.downloadSignal(inputSignal); % Send signal to PA via VST
outputSignal = vst.captureSignal(); % Capture output from PA
save('PA_IO_Data.mat', 'inputSignal', 'outputSignal'); % Save data for analysis

Steps to obtain Data without Hardware by simulating PA:

1. PA Model: Develop a model of your 'PA' in MATLAB based on its specifications. This could involve using MATLAB's RF Toolbox or directly implementing mathematical models of the PA's behavior (e.g., AM/AM, AM/PM conversion characteristics).
2. Simulation: Generate the same test signal as you would in the hardware scenario. Pass this signal through your PA model to simulate the output.
3. Save Simulated Data: Save both the input test signal and the simulated output for DPD development.

inputSignal = generateTestSignal(); % Your test signal
outputSignal = simulatePA(inputSignal); % Custom function to simulate PA output
save('PA_IO_SimulatedData.mat', 'inputSignal', 'outputSignal'); % Save data

Both approaches will provide you with the necessary input/output data for PA characterization, which is crucial for DPD implementation. The choice between hardware-based characterization and simulation depends on available resources and how closely you wish to mimic real-world conditions.

Hope that Helps!

Balavignesh