CDMA2000 Measurements
R&S
®
CMW-KM8xx/-KS8xx
738
User Manual 1173.9511.02 ─ 12
Fig. 5-10: CDMA2000 multi evaluation: spectrum
●
Spectrum FFT:
The RF signal is measured in time domain (refer to GPRF, chapter
" FFT Spectrum Analyzer" ) and FFT is used to calculate the displayed spectrum.
The application provides the signal power in dB and a frequency span up to 4.5
MHz around the analyzer center frequency and allows accurate power measure-
ments.
●
ACP:
The purple bar at the center of the "Spectrum" diagram indicates the power
at the nominal RF frequency (set to 0 dB), measured with a evaluation bandwidth
of
±
4 MHz from the nominal frequency. The blue bars to the left and the right show
the power at configurable offset frequencies. The resolution bandwidth at these off-
sets is selectable, see
Absolute ACP in dBm and the ACP in dBc relative to the carrier power can be dis-
played. The unit of measured ACP is selectable per frequency offset (dBc or dBm),
see
The ACP values are determined using a Gaussian filter for the resolution band-
width 1 kHz to 50 kHz and a Nyquist filter for the resolution bandwidth greater than
50 kHz. If limit checking is enabled, the red part of the lines indicate excessive
ACP (according to the configured limits).
The following measurements are available:
–
ACP measurement with 20 frequency offsets and speed 1000 measurements
in less than 10 seconds
–
Extended ACP measurement with 40 frequency offsets and speed 1000 mea-
surements in less than 15 seconds
The ACP results can also be viewed in tabular presentation, see
●
OBW:
The green vertical marker lines indicate the OBW, i.e. the bandwidth bearing
95 of the transmitted power. For spreading rate 1 the standard defines that the
OBW should not exceed 1.48 MHz.
General Description
深圳德标仪器
135-1095-0799
