3GPP-defined QPSK EVM (LTE)

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3GPP-defined QPSK EVM is the average EVM for PDSCH QPSK allocations. This EVM average is calculated according to 3GPP TS 36.141, Section F.4.1. This average includes all subframes in the Measurement Interval.

Data EVM and 3GPP-defined EVM summary table results may not exactly match since the standard requires that 3GPP-defined EVM be calculated per slot and then averaged over the measurement interval whereas all other EVM results computed by the LTE demodulator are calculated per symbol and then averaged over the measurement interval.

Section F.4.2 of 3GPP TS 36.141 specifies that 10 downlink subframes should be used to compute the the EVM average.

For TDD signals, Section F.4.2.1 of 3GPP TS 36.141 specifies that minimum number of frames be used so that at least 10 downlink subframes are included in the EVM average.