Agilent Technologies N9010A - Manual (Page 210)

210 Chapter 22
cdma2000 Measurement Application
Measurements
Description Specifications Supplemental Information
QPSK EVM
(−25 dBm ≤ ML a ≤ −15 dBm
20 to 30
°C)
RF input power and attenuation are
set to meet the Mixer Level range
EVM
Range
0 to 25
%
Floor 1.6
%
Accuracy
b ±1.0%
I/Q origin offset
DUT Maximum Offset
Analyzer Noise Floor
−10 dBc (nominal)
−50 dBc (nominal)
Frequency Error
Range
±30 kHz (nominal)
Accuracy
±5 Hz + tfa c
a. ML (mixer level) is RF input power minus attenuation.
b. The accuracy specification applies when the EVM to be measured is well above the measurement floor.
When the EVM does not greatly exceed the floor, the errors due to the floor add to the accuracy errors.
The errors due to the floor are noise-like and add incoherently with the UUT EVM. The errors depend
on the EVM of the UUT and the floor as follows: error = sqrt(EVMUUT
2
+ EVMsa
2
) - EVMUUT,
where EVMUUT is the EVM of the UUT in percent, and EVMsa is the EVM floor of the analyzer in
percent.
c. tfa = transmitter frequency
× frequency reference accuracy