Last Updated: August 29, 2007
This topic describes the Spectrum Emission Mask measurement. Spectrum Emission Mask is a measurement in the Dedicated Physical Channel measurement suite.
SEM is a relative measurement of the in-channel to the out-of-channel emissions. The purpose for this test is to measure the excess emissions that would interfere to other channels or to other systems.
The UE conformance specifications in 3GPP TS 34.121, Section 5.9 and 5.9A define a mask for out of channel emissions. This mask is defined relative to the in-channel power.
In-Channel Power
The in-channel power is measured after filtering the signal with a=0.22, Root-Raised Cosine (RRC) filter. This measurement result is identical to the RRC Filtered Mean Power measurement.
Note: The in-channel measurement automatically runs the RRC Filtered Mean Power measurement, so there is no need to run the RRC Filtered Mean Power measurement while you are running the SEM measurement.
The out-of-channel emissions are measured using a Gaussian filter with either in a 30 kHz or 1 MHz noise bandwidth. The out-of-channel power applies to frequencies that are between 2.5 and 12.5 MHz away from the center carrier frequency.
Spectrum Emission Mask is a measurement in the Dedicated Physical Channel measurement suite. See Dedicated Physical Channel Measurement Suite Measurement Parameters for details of the parameters that apply to measurements in the suite.
Spectrum Emission Mask is a measurement in the Dedicated Physical Channel measurement suite. See Dedicated Physical Channel Measurement Suite Measurement Limits for details of the limits parameters that apply to measurements in the suite.
This result provides the integrity indicator for the Dedicated Physical Channel measurement suite. Normal indicates that the measurement suite completed successfully without error and the result is accurate. For details of other integrity indicators, see Measurement Integrity Indicator.
SCPI command: FETCh:WDPChannel:INTegrity?
This result provides the overall pass/fail for the Spectrum Emission Mask measurement. If any out-of-channel frequency range does not comply with the standard, the entire mask fails.
SCPI commands: FETCh:WDPChannel:SEMask[:PARTial]?, FETCh:WDPChannel:SEMask:RANGe[:ALL]?
This result provides the in-channel power in dBm/3.84 MHz.
SCPI commands: FETCh:WDPChannel:SEMask:BAND[:ALL]?, FETCh:WDPChannel:SEMask:RANGe[:ALL]?
The following results are provided for each of the four individual frequency ranges; pass/fail, relative power level, frequency offset of the largest mask error, and the margin of that error.
SCPI commands: FETCh:WDPChannel:SEMask:RANGe[:ALL]?, FETCh:WDPChannel:SEMask:RANGe:RANGe([1]|2|3|4)?
SCPI commands: FETCh:WDPChannel:SEMask:BAND:LOWer([1]|2|3|4)[:ALL]?, FETCh:WDPChannel:SEMask:BAND:LOWer([1]|2|3|4):POINts?
SCPI commands: FETCh:WDPChannel:SEMask:BAND:UPPer([1]|2|3|4)[:ALL]?, FETCh:WDPChannel:SEMask:BAND:UPPer([1]|2|3|4):POINts?
This result provides the number of points tested for all bands in the spectrum emission mask measurement. This is the sum of all of the number of points calculated using the formulas for each band.
SCPI command: FETCh:WDPChannel:SEMask:BAND:POINts?
Spectrum Emission Mask is a measurement in the Dedicated Physical Channel measurement suite. See Dedicated Physical Channel Input Signal Requirements for details of the input signal requirements that apply to all measurements in the suite.