Last updated: January 18, 2010
During remote operation of the Output RF Spectrum measurement you should configure the trigger arm to single, see SETup:ORFSpectrum .
If the trigger arm is not set to single, the measurement may not return a result. When trigger arm is continuous the measurement rearms itself and starts another measurement cycle, during remote operation the fetch query may not be synchronized to the measurement cycle, see Measurement States .
ORFS due to modulation measurements: Averaging for each measurement, including the zero offset measurement, is performed over 40 or more bits on the front and back of the burst, from bit 15 to 60 and bit 87 to 132. ETSI standards only require measuring the back bits 87 to 132. By making measurements on the front and back of the burst, two measurements per burst are achieved.
When fetching (frequency offsets) for ORFS due to modulation or switching remotely, the values for the offsets are entered after the " ? ", see FETCh:ORFSpectrum:MODulation:FREQuency[:OFFSet][:AVERage]? or FETCh:ORFSpectrum:SWITChing:FREQuency[:OFFSet][:MAXimum]? for GPIB commands.
In order for the test set to return a valid switching measurement result when measuring two adjacent uplink bursts, you should ensure that the burst you have selected to measure has a higher expected power level than the other uplink burst in the multislot configuration. If the selected burst has a lower expected power level, the same hardware range settings cannot be used for both the modulation and switching measurements and the test set returns NAN for the switching measurement. The expected power can be set manually using RFANalyzer:MANual:POWer:BURSt<[1]|2|3|4|5|6|7> .
See Integrity Indicator .
If over range (5) is returned the input signal is likely to clip during the useful part of the burst or the ORFS TX Power measurement has detected an over range.
If signal too noisy (10) is returned, the actual power at certain offsets is > 8 dB off from the expected level.
If under range (6) is returned; the measured power result is more than 10 dB below the expected input power level. Under range is also indicated if, the input power is more than 2 dB below the calibrated range of the test set's power detector for the RF Range setting. RF Range is automatically set based on the input power setting. Input power is a combination of amplitude offset and expected power settings. See Mobile Station Receiver Example .