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step

System object: comm.EVM
Package: comm

Measure error vector magnitude

Syntax

RMSEVM = step(H,REFSYM,RXSYM)
[RMSEVM,MAXEVM] = step(H,REFSYM,RXSYM)
[RMSEVM,PEVM] = step(H,REFSYM,RXSYM)
[RMSEVM,NUMSYM] = step(H,REFSYM,RXSYM)
[RMSEVM,MAXEVM,PEVM,NUMSYM] = step(H,REFSYM,RXSYM)

Description

RMSEVM = step(H,REFSYM,RXSYM) outputs the root-mean-square EVM (in percent), RMSEVM, measured in the received signal, RXSYM, based on the reference signal, REFSYM. REFSYM and RXSYM inputs are complex column vectors of equal dimensions and data type. The data type can be double, single, signed integer, or signed fixed point with power-of-two slope and zero bias. The step method outputs the RMSEVM measurement based solely on the current input frame.

[RMSEVM,MAXEVM] = step(H,REFSYM,RXSYM) outputs the maximum EVM (in percent), MAXEVM, measured in the received signal, RXSYM, when you set the MaximumEVMOutputPort property to true. The step method outputs the MAXEVM measurement based on the reference signal, REFSYM. MAXEVM represents the worst-case EVM value measured in the current input frame.

[RMSEVM,PEVM] = step(H,REFSYM,RXSYM) outputs the percentile EVM (in percent), PEVM, measured in the received signal, RXSYM, when you set the XPercentileEVMOutputPort property to true. The step method outputs the PEVM measurement based on the reference signal, REFSYM. The object sets PEVM equal to a value just greater than the XPercentileValue percent of all the EVM values. For example, if you set the XPercentileValue property to 95, then 95% of all EVM measurements are below the PEVM value. The object calculates the persistent measurement PEVM, using all the input frames since the last reset.

[RMSEVM,NUMSYM] = step(H,REFSYM,RXSYM) outputs the number of symbols, NUMSYM, used to calculate the X-Percentile EVM measurements when you set the SymbolCountOutputPort property to true. All outputs of the object are of data type double. You can combine optional output arguments when you set their enabling properties. Optional outputs must be listed in the same order as the order of the enabling properties. For example,

[RMSEVM,MAXEVM,PEVM,NUMSYM] = step(H,REFSYM,RXSYM)

    Note:   The object performs an initialization the first time the step method is executed. This initialization locks nontunable properties and input specifications, such as dimensions, complexity, and data type of the input data. If you change a nontunable property or an input specification, the System object™ issues an error. To change nontunable properties or inputs, you must first call the release method to unlock the object.

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