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Frequency Dependent Nonlinear Amplifier
This project illustrates the use of the file based frequency dependent amplifier AMP_F. AMP_F utilizes an external text data file for configuration information. In this case, the data file "DATA" is made up of four columns. The file shows that Gain, OIP2, and OIP3 are dependent on frequency.
There are 2 system diagrams to illustrate and characterize different measurements.
The first diagram is titled Pwr Sweep. The VNA block sweeps the input power of AMP_F as well as its frequency. The resulting measurement of Pout (Output Power) can then be displayed versus both Pin (Input Power) and Frequency. The graph titled 2D Pout vs Pin vs Frequency illustrates the measurement in 2 dimensions while the graph titled 3D Pout vs Pin vs Frequency illustrates the same measurement in a 3 dimensional plot.
The second diagram is titled Freq Sweep. A single TONE is swept from 6GHz to 16GHz in increments of 0.25GHz. AMP_F's performance relative to the data file can be monitored in the graphs that are displayed. In each case, the original data is plotted along with the simulated data. The graphs from the Freq Sweep diagram are Gain vs Freq, IP2 vs Freq, IP3 vs Freq, Pout Pin vs Freq, and Spectrum Swept. IP2 and IP3 are measured using the IPn measurement.
The RBW setting in the VSA is set to 0.05GHz. In addition, FRQRES which is a secondary parameter on AMP_F must be manually adjusted to obtain better accuracy of Gain, IP2, and IP3 in the time domain simulations. The number of taps on the internal filters is determined by this parameter. See online help for details.
The VNA blocks control the sweeps. They sweeps frequency and power, respectively, and a minimum of 5000 samples are generated for each sweep.
Please read the online help for further information.