Chapter 3 109
Making EDGE (with GSM) Measurements
Making the EDGE EVM Measurement
Troubleshooting Hints
Use the spectrum (frequency domain) measurement to verify that the
signal is present and approximately centered on the display.
Poor phase error indicates a problem at the I/Q baseband generator,
filters, and/or modulator in the transmitter circuitry.The output
amplifier in the transmitter can also create distortion that causes
unacceptably high phase error. In a real system, poor phase error will
reduce the ability of a receiver to correctly demodulate the signal,
especially in marginal signal conditions.