Communication apparatus and communication method

US12562817B2 · US · B2

Patent metadata
FieldValue
Publication numberUS-12562817-B2
Application numberUS-202118274266-A
CountryUS
Kind codeB2
Filing dateFeb 4, 2021
Priority dateFeb 4, 2021
Publication dateFeb 24, 2026
Grant dateFeb 24, 2026

How to read this patent

A practical reading order for non-experts. Skip the full description unless you need deep technical detail.

  1. Title

    What the patent document calls the invention.

  2. Abstract

    A short plain-language summary of the technical disclosure.

  3. Assignees and inventors

    Who owns or filed the patent and who is credited as inventor.

  4. Key dates

    Filing, priority, publication, and grant dates set the timeline.

  5. First independent claim

    The legal scope of protection — read this for what is actually claimed.

  6. CPC / IPC classifications

    Technology tags used to group this patent with similar filings.

  7. Citations and related patents

    Prior art links and similar publications in this corpus.

Abstract

Official abstract text for this publication.

The communication device includes: a reception unit that receives burst frame signals from a plurality of other communication devices respectively; and a control unit that changes a block length of a moving average filter in carrier phase synchronization so as to minimize a phase noise amount of the burst frame signals.

First claim

Opening claim text (preview).

The invention claimed is: 1 . A communication device of a time division multiplexing passive optical network that includes the communication device and a plurality of communication devices, the communication device being an optical line termination device, the plurality of communication devices being optical network units, each having a different laser light source and each generating a burst frame signal by multilevel-modulating laser light output from the laser light source in wavelength synchronization with local oscillation light output from a local oscillation light source of the communication device, the communication device comprising: a receiver that coherently receives the burst frame signal respectively transmitted from the plurality of communication devices by using the local oscillation light source; a measurer that measures a phase noise amount from a preamble of the received burst frame signal or from the burst frame signal when a discovery operation is executed; and a controller that changes a block length of a moving average filter in carrier phase synchronization of a coherent receiver so as to minimize a phase noise amount of the burst frame signals for each received burst frame signal or for each execution period of the discovery operation. 2 . The communication device according to claim 1 , wherein the preambles of the burst frame signals are signals on which on-off keying modulation is performed. 3 . The control device according to claim 1 , wherein the controller changes the block length on the basis of information indicating an arrival time of each burst frame signal used in dynamic band allocation. 4 . The communication device according to claim 1 , wherein the burst frame signal obtained at the time of execution of the discovery operation is a signal on which on-off keying modulation is performed. 5 . The communication device according to claim 1 , the communication device further comprising: a compensator that compensates phase noise using a polarization pilot, wherein when the phase noise amount is equal to or greater than a predetermined value, the controller does not perform the carrier phase synchronization, and causes the compensator to compensate the phase noise. 6 . A communication method used by a communication device of a time division multiplexing passive optical network that includes the communication device and a plurality of communication devices, the communication device being an optical line termination device, the plurality of communication devices being optical network units each having a different laser light source and each generating a burst frame signal by multilevel-modulating laser light output from the laser light source in wavelength synchronization with local oscillation light output from a local oscillation light source of the communication device, the communication method comprising: coherently receiving the burst frame signal respectively transmitted from the plurality of communication devices by using the local oscillation light source; measuring a phase noise amount from a preamble of the received burst frame signal or from the burst frame signal when a discovery operation is executed; and changing a block length of a moving average filter in carrier phase synchronization of a coherent receiver so as to minimize a phase noise amount of the burst frame signals for each received burst frame signal or for each execution period of the discovery operation. 7 . The control device according to claim 1 , wherein the measurer selects, in time series, only data in an on-state where an optical power is present from the preamble, and performs a predetermined arithmetic processing on two adjacent data in the selected time series to calculate a variance value of a phase difference as the phase noise amount. 8 . The control device according to claim 1 , wherein the measurer selects, in time series, only data in an on-state in which an optical power is present from the burst frame signal when the discovery operation is executed, and sets the variance of a phase difference calculated by performing a predetermined arithmetic operation on two adjacent data in the selected time series as the phase noise amount.

Assignees

Inventors

Classifications

  • Star-type networks {or tree-type networks} · CPC title

  • using a supervisory or additional signal · CPC title

  • Fine synchronisation, e.g. by positioning the FFT window · CPC title

  • Amplitude-modulated carrier systems, e.g. using on-off keying; Single sideband or vestigial sideband modulation (H04L27/32 takes precedence) · CPC title

  • Estimation of the phase of the received optical signal, phase error estimation or phase error correction · CPC title

Patent family

Related publications grouped by family.

External sources

Frequently asked questions

Answers are generated from the same data shown on this page.

What does patent US12562817B2 cover?
The communication device includes: a reception unit that receives burst frame signals from a plurality of other communication devices respectively; and a control unit that changes a block length of a moving average filter in carrier phase synchronization so as to minimize a phase noise amount of the burst frame signals.
Who is the assignee on this patent?
Ntt Inc
What technology area does this patent fall under?
Primary CPC classification H04B10/6165. Mapped technology areas include Electricity.
When was this patent published?
Publication date Tue Feb 24 2026 00:00:00 GMT+0000 (Coordinated Universal Time) (B2). Legal status and post-grant events are not shown on this page.
What related patents are in patentsdb?
We list 6 related publications on this page (citations in our corpus or others sharing the same primary CPC).