Receiver
AssigneeMitsubishi Electric Corporation
InventorKeisuke Matsuda
Life of this patent
Estimating the term…
Abstract
A receiver is configured to extract a clock signal superimposed on a detection signal of light propagated to determine whether or not SNR of the detection signal is lower than SNR at which the detection signal can be demodulated; compensate a signal value of the detection signal by using a filter coefficient and output a detection signal after signal value compensation; and calculate, as the filter coefficient, a filter coefficient in which a signal value of a detection signal output from the adaptive filter is a reference value when it is determined that there is no SNR degradation, and changes the filter coefficient to a stored filter coefficient when it is determined that SNR degradation occurs.
Claims14
A receiver comprising:
- processing circuitry configured to
- extract a clock signal superimposed on a detection signal of light propagated through space;
- determine whether or not a signal-to-noise ratio of the detection signal is lower than a signal-to-noise ratio at which the detection signal is demodulated on a basis of an amplitude of the extracted clock signal;
- an adaptive filter to compensate a signal value of the detection signal by using a filter coefficient and output a detection signal after signal value compensation;
- calculate, as the filter coefficient, a filter coefficient in which a signal value of the detection signal output from the adaptive filter is a reference value;
- and
- store the calculated filter coefficient when the processing circuitry determines that there is no signal-to-noise ratio degradation, and change the filter coefficient used by the adaptive filter to a stored filter coefficient when the processing circuitry determines that signal-to-noise ratio degradation occurs.
A receiver comprising:
- processing circuitry configured to
- extract a clock signal superimposed on a detection signal of light propagated through space;
- determine whether or not a signal-to-noise ratio of the detection signal is lower than a signal-to-noise ratio at which the detection signal is demodulated on a basis of an amplitude of the extracted clock signal;
- compensate a frequency of the detection signal by phase-rotating the detection signal using a frequency compensation value, and output a detection signal after frequency compensation;
- calculate a frequency of the detection signal as the frequency compensation value;
- and
- store the calculated frequency compensation value when the processing circuitry determines that there is no signal-to-noise ratio degradation, and
- change the frequency compensation value used for phase rotation of the detection signal to a stored frequency compensation value when the processing circuitry determines that signal-to-noise ratio degradation occurs.
Dependencies are inferred from the claim text.