# US 11,451,365 B2 · Communications device and method of communications > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,451,365 B2 - Document ID: US11451365B2 - Status: Granted - Kind: B2 - Application number: 16/833,398 - Filed: 2020-03-27 - Published: 2020-10-01 - Granted: 2022-09-20 - Earliest claimed: 2019-03-29 - Assignees: NXP B.V. - Applicants: NXP B.V. - Inventors: Gerrit Willem den Besten - Web page: https://patentgrep.com/patent/US11451365B2 ## CPC - H04J 3/1694: {Allocation of channels in TDM/TDMA networks, e.g. distributed multiplexers (Passive Optical Networks H04Q11/0062)} - H04L 5/22: using time-division multiplexing - H04L 5/1469: {using time-sharing} - H04L 12/40156: {by using dedicated slots associated with a priority level} - H04J: MULTIPLEX COMMUNICATION (transmission in general H04B; peculiar to transmission of digital information H04L5/00; systems for the simultaneous or sequential transmission of more than one television signal H04N7/08; in exchanges H04Q11/00; stereophonic systems H04S) - H04L: TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION (arrangements common to telegraphic and telephonic communication H04M) ## Abstract Methods for communications and of communication device involve determining a half-duplex communications mode for a communications device, and in response to determining the half-duplex communications mode for the communications device, disabling an echo canceller of the communications device and determining a time-division multiplex (TDM) communications schedule over a point-to-point communications link. In response to disabling the echo canceller and determining the TDM communications schedule over the point-to-point communications link, data transmission is conducted over the point-to-point communications link according to the TDM communications schedule without echo cancellation at the communications device. The TDM communications schedule specifies non-overlapping transmission time slots for different communications devices and a silent period for echo fade-out between consecutive transmission time slots of the non-overlapping transmission time slots. ## Claims ### Claim 1 A method of communications, the method comprising: determining a half-duplex communications mode for a communications device for a first time period and determining a full-duplex communications mode for the communications device for a second time period; in response to determining the half-duplex communications mode for the communications device for the first period: disabling an echo canceller of the communications device during the first time period; determining a time-division multiplex (TDM) communications schedule over a point-to-point communications link, wherein the TDM communications schedule specifies a plurality of non-overlapping transmission time slots for different communications devices and a silent period for echo fade-out between consecutive transmission time slots of the non-overlapping transmission time slots; and in response to disabling the echo canceller and determining the TDM communications schedule over the point-to-point communications link, conducting data transmission over the point-to-point communications link according to the TDM communications schedule without echo cancellation during the first time period using the communications device; and in response to determining the full-duplex communications mode for the communications device for the second period: enabling the echo canceller of the communications device; and in response to enabling the echo canceller, conducting simultaneous bidirectional transmission over the point-to-point communications link with echo cancellation using the communications device during the second time period. ### Claim 2 (depends on 1) The method of claim 1, further comprising training the point-to-point communications link prior to conducting the data transmission over the point-to-point communications link according to the TDM communications schedule without echo cancellation using the communications device. ### Claim 3 (depends on 2) The method of claim 2, wherein training the point-to-point communications link comprises: in a first direction of the point-to-point communications link, conducting continuous transmission from a first transceiver to a second transceiver while the second transceiver does not transmit data over the point-to-point communications link. ### Claim 4 (depends on 3) The method of claim 3, wherein training the point-to-point communications link further comprises, in a second direction of the point-to-point communications link that is opposite to the first direction, transmitting data from the second transceiver to the first transceiver to train the point-to-point communications link during a time slot assigned to the second transceiver while the first transceiver stops data transmission during the time slot assigned to the second transceiver. ### Claim 5 (depends on 2) The method of claim 2, wherein training the point-to-point communications link comprises extending a training transmit slot in a direction of training and reducing a transmission slot for a direction of the point-to-point communications link that is opposite to the direction of training. ### Claim 6 (depends on 1) The method of claim 1, wherein said conducting the data transmission over the point-to-point communications link according to the TDM communications schedule without echo cancellation during the first time period comprises transmitting data only during a fraction of an assigned transmission time slot according to the TDM communications schedule over the point-to-point communications link. ### Claim 7 (depends on 1) The method of claim 1, further comprising: adjusting the TDM communications schedule over the point-to-point communications link based on a bandwidth in one direction of the point-to-point communications link. ### Claim 8 (depends on 1) The method of claim 1, further comprising: adjusting a length of at least one of the non-overlapping transmission time slots of the TDM communications schedule. ### Claim 9 (depends on 1) The method of claim 1, further comprising: synchronizing with an Energy-Efficient Ethernet (EEE) communications schedule. ### Claim 10 (depends on 1) The method of claim 1, wherein said conducting data transmission over the point-to-point communications link according to the TDM communications schedule without echo cancellation during the first time period comprises transmitting data only once during multiple TDM cycles over the point-to-point communications link. ### Claim 11 (depends on 1) The method of claim 1, wherein at least one of the non-overlapping transmission time slots contains time to transmit an integer number of data frames over the point-to-point communications link. ### Claim 12 (depends on 1) The method of claim 1, wherein the communications device is part of an in-vehicle network (IVN). ### Claim 13 (depends on 1) The method of claim 1, wherein communications in different directions of the point-to-point communications link occur at different data rates. ### Claim 14 (depends on 1) The method of claim 1, further comprising determining a time duration of the silent period based on a communications channel length of the point-to-point communications link or based on a baud rate of the point-to-point communications link. ### Claim 15 A communications device comprising: a controller configured to: determine a half-duplex communications mode for a communications device for a first period; and determine a half-duplex communications mode for a communications device for a first period; in response to determining the half-duplex communications mode for the communications device: disable an echo canceller of the communications device; and determine a time-division multiplex (TDM) communications schedule over a point-to-point communications link, wherein the TDM communications schedule specifies a plurality of non-overlapping transmission time slots for different communications devices and a silent period for echo fade-out between consecutive transmission time slots of the non-overlapping transmission time slots; and in response to determining the full-duplex communications mode for the communications device, enable the echo canceller of the communications device; and a transceiver configured to: in response to disabling the echo canceller and determining the TDM communications schedule over the point-to-point communications link, conduct data transmission over the point-to-point communications link according to the TDM communications schedule without echo cancellation during the first time period; and in response to enabling the echo canceller, conduct simultaneous bidirectional transmission over the point-to-point communications link with echo cancellation during the second time period. ### Claim 16 (depends on 15) The communications device of claim 15, wherein the transceiver is further configured to train the point-to-point communications link prior to conducting the data transmission over the point-to-point communications link according to the TDM communications schedule without echo cancellation at the communications device. ### Claim 17 A wired communications network comprising: a wired transmission media; and a plurality of communications devices configured to communicate via the wired transmission media, wherein each of the communications devices comprises: a controller configured to: determine, for a first time period, a half-duplex communications mode for a communications device and determine, for a second time period, a full-duplex communications mode for the communications device; in response to determining the half-duplex communications mode for the communications device for the first time period: determine a time-division multiplex (TDM) communications schedule over a point-to-point communications link for the first time period, wherein the TDM communications schedule specifies a plurality of non-overlapping transmission time slots for different communications devices and a silent period for echo fade-out between consecutive transmission time slots of the non-overlapping transmission time slots; and disable an echo canceller of the communications device during the first timer period; and in response to determining the full-duplex communications mode for the communications device for the second time period, enable the echo canceler of the communications device; a transceiver configured to: in response to disabling the echo canceller and determining the TDM communications schedule over the point-to-point communications link, conduct data transmission over the point-to-point communications link according to the TDM communications schedule without echo cancellation during the first time period; and in response to enabling the echo canceller, conduct simultaneous bidirectional transmission over the point-to-point communications link with echo cancellation at the communications device during the second time period.