Service manual

Remote Commands for WLAN TX Measurements
R&S
®
FSV-K91/91n/91ac/91p
211Operating Manual 1176.7649.02 ─ 04
5.16.2 I/Q Measurements
There are a number of measurements that can be performed in I/Q mode. No data is
returned for any of the following measurements, should it be requested, until a mea-
surement belonging to the I/Q group has been run. Running a frequency sweep mea-
surement, for example Spectrum Mask, does not generate results for this measure-
ment group.
5.16.2.1 Constellation vs Symbol
This measurement represents I and Q data. Each I and Q point is returned in floating
point format. TRACE1 is used for these measurement results.
For the IEEE 802.11a, j and n standard, data is returned as a repeating array of inter-
leaved I and Q data in groups of selected carriers, until all the data is exhausted. The
following rules apply:
●
If "All Carriers" is selected, 52 pairs of I and Q data per symbol are returned.
●
If "Pilots Only" is selected, 4 pairs of I and Q data per symbol are returned in the
following order: Carrier –21, Carrier –7, Carrier 7, Carrier 21.
●
If a single carrier is selected, 1 pair of I and Q data per symbol is returned.
For IEEE 802.11n only:
●
20 MHz Channel Bandwidth.
If "All Carriers" is selected, it will return 56 pairs of I and Q data per symbol. If
"Pilots Only" is selected, it will return 4 pairs of I and Q per symbol in the following
order: Carrier –21, Carrier –7, Carrier 7, Carrier 21. If a single carrier is selected, it
will return 1 pair of I and Q data per symbol.
●
40 MHz Channel Bandwidth
If "All Carriers" is selected, it will return 116 pairs of I and Q data per symbol. If
"Pilots Only" is selected, it will return 6 pairs of I and Q per symbol in the following
order: Carrier –53, Carrier –25, Carrier –11, Carrier 11, Carrier 25, Carrier 53. If a
single carrier is selected, it will return 1 pair of I and Q data per symbol.
For IEEE 802.11b, the data is returned as a repeating array of interleaved I and Q data
in symbol order until all the data is exhausted.
5.16.2.2 Constellation vs Carrier
This measurement represents I and Q data. Data is returned as a repeating array of
interleaved I and Q data in groups of 53 channels (57 within the n standard) including
DC, until all the data is exhausted. The IEEE 80211n Standard has 57 carrier for
20MHz channel bandwidth including DC and 117 carriers for 40MHz channel band-
width including 3 DC.
Each I and Q point is returned in floating point format. TRACE1 is used for these mea-
surement results.
Supported data formats (see FORMat[:DATA] on page 176): ASCii|REAL
TRACe Subsystem (WLAN)