Burst Synchronization of Measurements
Last updated: May 8, 2002
Measurement Synchronization
Measurement Synchronization Description
Measurement synchronization determines how a measurement's time reference is determined from the measurement data (a sampled time record). Measurement synchronization occurs after the measurement data is captured.
For the transmit power and ORFS (switching and modulation) measurements, the RF amplitude of the input signal is used for measurement synchronization. For Phase and Frequency Error Measurement and the Power versus Time Measurement (see
Phase and Frequency Error Measurement Description
and
Power versus Time Measurement Description
.) there are three possible settings for measurement synchronization:
-
Midamble
-
RF Amplitude
-
None
Selecting midamble causes the test set to use the input signal's midamble data to determine the measurement's time reference. A measurement is capable of midamble synchronization if the test set is able to determine transmitted data from measurement samples (i.e. perform demodulation). Midamble synchronization is not available for Transmit Power measurements. However, the Power vs. Time measurement can perform an average power measurement using midamble synchronization.
When the test set's operating mode is "test mode" or when the cell activated state is "off", the burst type may need to be specified before the test set can synchronize to the input signal's midamble. See
Expected Burst
.
Selecting RF amplitude causes the test set to use the input signal's rising and falling edges (if edges are detected within the sampled time record) to determine the measurement's time reference. If a non-bursted signal was sampled, the measurement's time reference will be developed using the beginning and end of the sampled time record, and the samples used for making the measurement will be taken from the middle of the time record.
Selecting None causes the test set to perform measurements exactly as if RF amplitude was chosen.
An integrity indicator is returned for each completed measurement. Integrity errors are prioritized so that when multiple errors occur, the highest priority error is returned first, as the root error. The integrity indicator returns a number from 0 to 16, where 0 indicates normal. The following integrity indicators reveal problems with measurement synchronization:
-
(7) Burst Short
-
(8) Trigger Early
-
(8) Fall Early
-
(9) Trigger Late
-
(9) Rise Late
-
(11) Sync Not Found
Refer to
Integrity Indicator
for descriptions of integrity indicators.
Programming Example:
OUTPUT 714;"SETUP:PVTIME:SYNC MIDAMBLE"!selects midamble synchronization for PVT measurements
