Waveguide estimation apparatus, waveguide estimation method and program
A waveguide estimation device includes: a time window processing unit that multiplies time-series tap coefficients of an adaptive filter by a time window function; and an estimation unit that estimates at least one of a differential group delay in a frequency series or a time series and a polarization dependent loss in a frequency series or a time series based on the time-series tap coefficients in a time window. The estimation unit may estimate at least one of the differential group delay in a frequency series or a time series and the polarization dependent loss in a frequency series or a time series based on a tap coefficient exceeding a lower limit threshold value or falling below an upper limit threshold value among the time-series tap coefficients in a time window. The estimation unit may estimate the average value of the differential group delays in a frequency series or a time series. The time window processing unit may determine the length of the time window based on a constant multiple of the average value.
1 . A waveguide estimation device comprising:
a time window processor that multiplies time-series tap coefficients of an adaptive filter by an apodization function; and
an estimator that estimates at least one of a differential group delay in a frequency series or a time series and a polarization dependent loss in a frequency series or a time series based on the time-series tap coefficients in a time window,
wherein the estimator estimates at least one of the differential group delay in a frequency series or a time series and the polarization dependent loss in a frequency series or a time series based on a tap coefficient exceeding a lower limit threshold value or falling below an upper limit threshold value among the time-series tap coefficients in the time window.
2 . The waveguide estimation device according to claim 1 , wherein
the estimator estimates an average value of differential group delays in a frequency series or a time series, and the time window processor determines a length of the time window based on a constant multiple of the average value.
3 . The waveguide estimation device according to claim 1 , further comprising a frequency window processor that cuts out a frequency series used for Fourier transform of the time-series tap coefficients for each frequency domain,
wherein the estimator estimates at least one of the differential group delay in a frequency series or a time series and the polarization dependent loss in a frequency series or a time series based on the time-series tap coefficients in the time window for each of the cut frequency series.
4 . A non-transitory computer readable storing a program for causing a computer to function as the waveguide estimation device according to claim 1 .
5 . A waveguide estimation method executed by a waveguide estimation device, the method comprising:
a time window processing step of multiplying time-series tap coefficients of an adaptive filter by an apodization function; and
an estimation step of estimating at least one of a differential group delay in a frequency series or a time series and a polarization dependent loss in a frequency series or a time series based on the time-series tap coefficients in a time window,
wherein the estimation step further includes a step of estimating at least one of the differential group delay in a frequency series or a time series and the polarization dependent loss in a frequency series or a time series based on a tap coefficient exceeding a lower limit threshold value or falling below an upper limit threshold value among the time-series tap coefficients in the time window.
6 . The waveguide estimation method according to claim 5 , wherein
the estimation step further includes a step of estimating an average value of differential group delays in a frequency series or a time series, and the time window processing step further includes a step of determining a length of the time window based on a constant multiple of the average value.