Tektronix OM4006D, Руководство пользователя

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Core Processing function reference
ApplyPhase
[Y,BoundValsOut,AlertsOut] = ApplyPhase(X,Theta,BoundValsIn,AlertsIn)
X – single or dual polarization parameter vs. time:
.t0 – time of fi rst symbol
.dt – symbol duration
.Values – 1xN or 2xN array of complex values
Theta – phase to be applied:
.t0 – time of fi rst symbol
.dt – symbol duration
.Values – row vector of phase values (radians)
.CentFreq – frequency offset between local oscillator and optical signal
BoundValsIn – structure of boundary values from previous block
AlertsIn – structure of alerts accumulated before executing function
Y – result of applying phase adjustment to X
BoundValsOut – structure of boundary values to be passed to next block
AlertsOut – structure of alerts including any alerts raised during execution of
function
This function multiplies X.Values by a phase factor to give Y.Values. X may be a
single or dual polarization representation.
There is no requirement that Theta has the same time grid as X. If they have
different time grids then the values of Theta are interpolated to align with the time
grid of X. This means that Theta may be derived for symbol center times, for
example, and then applied to a waveform having a
fi ner grid.
The actual values of phase that are used take into account the heterodyne frequency
CentFreq, that is, 2*pi*Theta.CentFreq*(0:number of symbols-1)+Theta.Values
ClockRetime
[p,BoundValsOut,AlertsOut] =
ClockRetime(V,ChDelay,pHyb,Clock,BoundValsIn,AlertsIn)
V – 1x4 array of structures, each containing waveform (voltage values) from
scope
ChDelay – 4-element vector of time delays between scope channels, usually
obtained by separate calibration
94 OM4000D Series Coherent Lightwave Signal Analyzer