DemodOFDMErrInfo

This is a Data Header variable.

Type = Array of Float

DemodOFDMErrInfo is similar to the DemodErrInfo array used for regular digital demod and the Demod3GChanErrInfo and Demod3GCompErrInfo arrays for 3G digital demod. The values in this array provide summary error information about the OFDM Orthogonal Frequency Division Multiplexing: OFDM employs multiple overlapping radio frequency carriers, each operating at a carefully chosen frequency that is Orthogonal to the others, to produce a transmission scheme that supports higher bit rates due to parallel channel operation. OFDM is an alternative tranmission scheme to DSSS and FHSS. demodulation.

The length of this array is equal to vsaTrcDemOFDMErrInfoCount. The values in this array are:

• vsaTrcDemOFDMErrInfoEvmRms - The RMS level of the normalized Error Vector for all subcarriers and all symbol times in the measurement. Only the symbol times specified by Meas Interval and Meas Offset are used to compute this. The units are percent.

• vsaTrcDemOFDMErrInfoEvmPk - The peak magnitude of the normalized Error Vector for all subcarriers and all symbol times in the measurement. Only the symbol times specified by Meas Interval and Meas Offset are used to compute this. The units are percent.

• vsaTrcDemOFDMErrInfoEvmPkSym - The symbol number of the peak magnitude of the normalized Error Vector. Only the symbol times specified by Meas Interval and Meas Offset are used to compute this.

• vsaTrcDemOFDMErrInfoMagErrRms - Not implemented, set to zero.

• vsaTrcDemOFDMErrInfoMagErrPk - Not implemented, set to zero.

• vsaTrcDemOFDMErrInfoMagErrPkSym - Not implemented, set to zero.

• vsaTrcDemOFDMErrInfoPhaseErrRms - Not implemented, set to zero.

• vsaTrcDemOFDMErrInfoPhaseErrPk - Not implemented, set to zero.

• vsaTrcDemOFDMErrInfoPhaseErrPkSym - Not implemented, set to zero.

• vsaTrcDemOFDMErrInfoFreqErr - The frequency error, equal to the difference between the measured center subcarrier frequency and the instrument center frequency. The units are Hz. The measured center subcarrier frequency is estimated from both the burst preamble and the data symbol times specified by Meas Interval and Meas Offset.

• vsaTrcDemOFDMErrInfoIqOffset - The IQ offset of the signal, which is the center subcarrier feedthrough. This is estimated from the burst preamble. The value is a unitless power ratio.

• vsaTrcDemOFDMErrInfoSyncCorr - The correlation between the burst preamble sync and the ideal sync signal. For 802.11a signals, the correlation is done on the short sync portion of the preamble. For HiperLan/2 signals, the correlation is done on the long sync portion of the preamble because there may not be a short sync present. This value is a unitless value between zero and one, where one is perfect correlation and zero is no correlation.

• vsaTrcDemOFDMErrInfoLSEvm - Not implemented, set to zero.

• vsaTrcDemOFDMErrInfoPilotEvm - The RMS level of the normalized Error Vector for the pilot subcarriers at all symbol times in the measurement. Only the symbol times specified by Meas Interval and Meas Offset are used to compute this. The units are percent.

• saTrcDemOFDMErrInfoCpeRms - The RMS level of the Common Pilot Error. The ideal Common Pilot Error has a magnitude of one and a phase of zero, so this RMS level is really computed from the Common Pilot Error minus one. only the symbol times specified by the Meas Interval and Meas Offset are used to compute this. The units are percent.

• vsaTrcDemOFDMErrInfoOctets - The number of decoded octets in the burst (one octet is eight bits), as detected in the SIGNAL symbol. The value does not include the bits in the SIGNAL symbol itself. For HiperLan/2 signals, the value is specified as 1e10, meaning that the value does not apply and should be displayed as "N/A".

• vsaTrcDemOFDMErrInfoNSym - The number of symbols in the burst, after the SIGNAL symbol, as detected in the SIGNAL symbol. For HiperLan/2 signals, the value is specified as 1e10, meaning that the value does not apply and should be displayed as "N/A".

• vsaTrcDemOFDMErrInfoCodingRateNum - The numerator of the coding rate of the convolutional coder, as detected in the SIGNAL symbol. For HiperLan/2 signals, the value is specified as 1e10, meaning that the value does not apply and should be displayed as "N/A".

• vsaTrcDemOFDMErrInfoCodingRateDen - The denominator of the coding rate of the convolutional coder, as detected in the SIGNAL symbol. For HiperLan/2 signals, the value is specified as 1e10, meaning that the value does not apply and should be displayed as "N/A".

• vsaTrcDemOFDMErrInfoBitsPerSym - The number of bits per symbol per subcarrier, determined by the modulation format specified in the SIGNAL symbol. For HiperLan/2 signals, the value is specified as 1e10, meaning that the value does not apply and should be displayed as "N/A".

• vsaTrcDemOFDMErrInfoBitRate - The calculated decoded bit rate of the signal, computed from the detected coding rate and modulation type in the SIGNAL symbol, and from the symbol rate as specified by the user. For HiperLan/2 signals, the value is specified as 1e10, meaning that the value does not apply and should be displayed as "N/A".