Modulation Measurements

Measurements

Composite Measurement

The next class of measurements are of the Composite signal. This measures the entire coded WCDMA signal and provides metrics for the entire signal in both uplink and downlink modes. A standard measurement of the transmitter is the Composite EVM (shown in the summary table). This is the EVM of a signal that has all of the active codes combined together for the entire transmitter.

3GPP has “Composite EVM” conformance specifications similar to QPSK, but they look very different due to the different signals. Each code is demodulated, then combined to get a composite waveform. The composite measurement also supports HSDPA signals along with several additional measurements such as:

Scramble Code

Peak Code Domain Error

Power in the Synchronizing Channel (SCH)

Figure 5-31.Composite Graph Type Selection Dialog

5-54

MS278XB OM

Page 210
Image 210
Anritsu Series MS278XB Modulation Measurements Composite Measurement, Composite Graph Type Selection Dialog