Atec Agilent-E4406A - Manual (Page 7)

QPSK EVM measurement
The QPSK EVM measurement measures the modulation
quality of QPSK modulated signal. This measurement pro-
vides an IQ constellation diagram, error vector magnitude
(EVM) in RMS and peak as well as magnitude error versus
chip, phase error versus chip, and EVM versus chip.
QPSK EVM QPSK selected
Minimum power –20 dBm (nominal)
at RF input
EVM
Operating range 0 to 25% (nominal)
Floor 1.5% (nominal)
Accuracy ±1.0% (nominal) at
EVM of 10%
I/Q origin offset
Range –10 to –50 dBc (nominal)
Frequency error
Range ±300 kHz (nominal)
Accuracy ±10 Hz (nominal) +
(transmitter frequency x
frequency reference accuracy)
QPSK EVM 12.2k RMC selected
Minimum power –20 dBm (nominal)
at RF input
EVM
Operating range 0 to 20% (nominal)
Floor 1.5% (nominal)
Accuracy ±1.0% (nominal) at
EVM of 10%
I/Q origin offset
Range –10 to –50 dBc (nominal)
Frequency error
Range ±20 kHz (nominal)
Accuracy ±10 Hz (nominal) +
(transmitter frequency x
frequency reference accuracy)
Modulation accuracy measurement (composite EVM)
Composite EVM is a measure of the performance of a
W-CDMA transmitter’s modulation circuitry. Composite
EVM can be measured for a pilot channel along with other
channel structures, i.e. multiple traffic channels.
Minimum power –70 dBm (nominal)
at RF input
Composite EVM Using Test Model 4
Range 0% to 25%
Floor 1.5%
Accuracy ±1.0%
Peak code domain error Using Test Model 3 with
16 DPCH w/spreading code
of 256
Accuracy ±1.0 dB (nominal)
I/Q origin offset
Range –10 to –50 dBc (nominal)
Frequency error Specified for CPICH power
≥
–15 dBc
Range ±500 Hz
Accuracy ±2 Hz + (transmitter frequency x
frequency reference accuracy)
Time offset
Frame offset accuracy ±150 nsec
Relative offset accuracy ±1.25 nsec
Intermodulation distortion measurement
The intermodulation distortion measurement determines
the third order and fifth order intermodulation products
caused by nonlinear devices in the transmitter. This mea-
surement is made with two single tones or a single tone
and a modulated W-CDMA signal. The results are displayed
in relative power to the carrier in dBc or in absolute power
in dBm.
Minimum carrier power –20 dBm (nominal)
at RF input
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