Tektronix OM4006D, Руководство пользователя

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Core Processing function reference
NumBitsVar takes on one of two forms. If it is a positive integer value then that is
used as the number of bits to generate in output parameter Seq. The time
fi eld
Patt.t0 is ignored (if it exists). The output sequence starts with Patt.Seed in the
case of a PRBS, or Seq starts at position Patt.Start in the case of a speci
fi ed data
pattern.
Alternatively, NumBitsVar may have fi elds’ .t0 and .dt, in which cases the
difference between NumBitsVar.t0 and Patt.t0 is used, together with Patt.dt, to
determine the start point of Seq. The offset in time may be positive or negative.
It is acceptable for NumBitsVar to have other
fi elds, for example a .Values fi eld,
because they are ignored.
Note that Seq is not a structure. It is a variable containing a row vector of logical
values, and does not have .t0 and .dt
fi elds.
Jones2Stokes
Y = Jones2Stokes(X)
X – 2xN array, row of Jones vectors
Y – 3xN array, row of Stokes vectors
This function converts a row of Jones vectors into a row of Stokes vectors.
JonesOrth
Y = JonesOrth(X)
X – 2xN array, row of Jones vectors
Y – 2xN array, row of Jones vectors, each orthogonal to the corresponding
Jones vector in X
This function converts a row of Jones vectors into a row of Jones vectors
representing the orthogonal state of polarization.
In general there are many Jones vectors that are orthogonal to a given Jones
vector. The many vectors can have different absolute values and also they can be
related to one another by a phase factor. The output Y of JonesOrth is chosen to
have the same absolute value as input X, and the
fi rst element of Y is real.
OM4000D Series Coherent Lightwave Signal Analyzer 103