Computing ACPR, EVM and PAE with ADS Ptolemy Simulation
应用文章
Problem description
You’re designing a power amplifier that must meet ACPR and EVM specifications while delivering a specified output power. You need this data, but you also need to see how these performances vary due to statistical variation. In addition, given that you have design parameters you can adjust to improve performances, which parameters matter, and to what values should they be set? This example and document show a method of doing this with ADS.
Background about this technique
With ADS Ptolemy co-simulation, a specification-compliant source is used to generate a modulated signal (EDGE, in this example) which is supplied to a power amplifier subcircuit under test. The output from the power amplifier is then measured using specification-compliant sinks to determine the adjacent- and alternate-channel power ratios, the error vector magnitude, and the mean transmitted RF carrier power. In addition, bias voltages and currents in the amplifier subcircuit are measured to determine the average DC power consumption, enabling efficiency calculations.