Power Linearity Example (RF Signals)

[Justin.]

Overview

Power Linearity is an industry standard test for characterising the ability of a Power Amplifier (PA) in RF Systems. The test itself is a measure of the desired output of the PA, as specified by a user, measured against the actual output of the PA. The typical result you retrieve from this is the limit at which the PA works perfectly. You may want to retrieve an idea of at what power levels does desired output not equal actual output, or is there a consistent offset for all measurements.

Description

This VI was written to accomplish a Power Linearity test. The VI itself uses multiple loops for two reasons. Firstly, performing the test itself does need specific loops, secondly, there is an event handling loop and a display loop. Both of these loops are introduced to allow for scalability of the VI, the VI can be used as a template for Power Linearity but there is room for improvement to either allow more specific tests or more types of tests. There are three important parameters to configure; the starting power, i.e. the first (and lowest) power level you wish to generate. The interval, this determines the difference between power levels tested as you perform power linearity. The maximum power, this determines the last power level that the power linearity test will generate, this is a safety implementation to preserve the PA.

Steps to Implement or Execute Code

1. Run the VI.
2. Configure the resource to use as your RF Instrument
3. Configure the parameters of start power, interval and maximum power.
4. Once parameters are configured, press the Power Linearity button.
5. Press Stop to end the application.

Requirements

Software

LabVIEW 2013

RF Drivers Suite

Hardware

An instrument that can generate and analyse RF Signals. This example was created using the VST 5644R.

Additional Images or Video