Embodiments relate to optical transport technologies, and more specifically, to a clock transmission method. Under this method, a first optical data unit (ODU) container can be obtained. Phase discrimination can be performed on an obtained first clock and a first ODU clock of a transmit end, to generate a first PD value. The first PD value can then be inserted into an overhead of the first ODU container. The first ODU container can be encapsulated into a second ODU container, and the second ODU container can be sent. A rate of the second ODU container is higher than a rate of the first ODU container. The first PD value is transmitted in the first ODU container which is not decapsulated in a subsequent transmission process. Therefore, final recovery of the first clock is not affected, so that a deviation between a finally recovered clock and the first clock is greatly reduced.

[Problem to be Solved] To provide a serial data transmission device that makes it possible to dynamically switch a band or a data transmission path and enhance the stability to failure while multiplexing and transmitting data by a TDM method when serial data is transmitted between a plurality of daisy-chained data transmission devices. [Solution] There is provided a serial data transmission device including: a receiver that receives data serially transmitted by a time-division multiplex method from another device daisy-chained to the serial data transmission device; a transmitter that serially transmits data by the time-division multiplex method to another device daisy-chained to the serial data transmission device; and a controller that controls serial transmission by the receiver and the transmitter, in which the controller performs control to make the serial transmission by the transmitter adjustable.

Systems and methods presented herein provide for an LTE wireless communication system operating in a Radio Frequency (RF) band with a conflicting wireless system. The LTE system includes an eNodeB operable to detect a plurality of UEs in the RF band, to generate LTE frames for downlink communications to the UEs, and to time-divide each LTE frame into a plurality of subframes. The eNodeB is also operable to condense the downlink communications into a first number of the subframes that frees data from a remaining number of the subframes in each LTE frame, and to burst-transmit the first number of the subframes of each LTE frame in the RF band.

Systems and methods presented herein provide for altering communications of a LTE wireless communication system operating in an RF band with a conflicting WiFi system. In one embodiment, an LTE system includes a wireless base station operable to transmit downlink communications to a UE in the RF band and to receive uplink communications from the UE in the RF band. The LTE system also includes a processor operable to detect the uplink communications from the UE, to estimate a location of the UE based on the detected uplink communications, to determine a communication capability between the UE and the wireless base station based on the location of the UE, and to downgrade the downlink communications from the wireless base station to the UE based on the determined communication capability to avoid interference with the WiFi communication system.

An automotive communication system includes multiple communication devices and a processor. The communication devices are configured to be installed in a vehicle and to communicate with one another over point-to-point Ethernet links. In each Ethernet link, a first communication device serves as a link master that is configured to set a clock signal for the link, and a second communication device serves as a slave that is configured to synchronize to the clock signal set by the first communication device. The communication devices are configured to receive data from sensors and to transmit the data over the Ethernet links. The processor is configured to receive the data from the communication devices over the Ethernet links, to synchronize the data originating from the multiple sensors to a common time-base based on link-specific clock-signal synchronization achieved on each of the links by each link master, and to process the synchronized data.

Techniques associated with link establishment in a fronthaul network are described herein. In one embodiment, a method includes receiving, by a proxy node, a Common Public Radio Interface (CPRI) bit stream transmitted by a radio equipment controller, wherein the CPRI bit stream is transmitted within a transmit time interval of the radio equipment controller; and fast-sampling, by the proxy node, the CPRI bit stream to determine whether a hyper frame number synchronization with the radio equipment controller at a common matching link bit rate is achievable, wherein the fast-sampling comprises attempting to decode the received CPRI bit stream and achieve the hyper frame number synchronization for each of a plurality of link bit rates configured for a fast-sampling time period during at least one fast-sampling time interval configured for the proxy node.

Techniques that provide link establishment between a radio equipment controller (REC) and a radio equipment (RE) in a fronthaul network are described herein. In one embodiment, a method includes performing, Common Public Radio Interface (CPRI) Layer 1 (L1) link auto-negotiation operations to establish a CPRI link between the REC and RE. A proxy slave may achieve a hyper frame number (HFN) synchronization with the REC at a link bit rate for a first CPRI bit stream and communicate the first CPRI bit stream and the link bit rate to a proxy master. The proxy master may communicate a second CPRI bit stream to the proxy slave to transmit to the REC. The L1 link auto-negotiation operations are completed and CPRI link is established between the REC and the RE when the REC achieves a HFN synchronization for the second CPRI bit stream.

A priority verification unit (110) obtains from, among a plurality of communication apparatuses, other communication apparatus other than a current grandmaster, a grandmaster mediation message that is a grandmaster mediation message used for selecting a grandmaster and that includes a priority of the other communication apparatus. The priority verification unit (110) verifies whether or not the priority of the other communication apparatus is higher than a grandmaster priority (22). A mediation unit (120), when the priority of the other communication apparatus is verified as being higher than the grandmaster priority (22), to obtain a synchronization message including time of the other communication apparatus from the other communication apparatus before switching the other communication apparatus to the grandmaster. The mediation unit (120) calculates difference between the time of the other communication apparatus and time of the communication apparatus, and when the difference is less than a threshold (23), switches the other communication apparatus to the grandmaster.

Embodiments of the present invention provide a flexible Ethernet latency measurement method and a related device. The method includes: determining, by a first node, first duration based on a first downlink transmission time interval and a second downlink receiving time interval; determining, by the first node, second duration based on a first uplink transmission time interval and a second uplink receiving time interval; and calculating, by the first node, an uplink and downlink latency difference between the first node and the second node based on the first duration and the second duration. According to the embodiments of the present invention, costs for measuring an asymmetric uplink and downlink latency can be reduced.

Techniques associated with link establishment in a fronthaul network are described herein. In one embodiment, a method includes receiving, by a proxy node, a Common Public Radio Interface (CPRI) bit stream transmitted by a radio equipment controller, wherein the CPRI bit stream is transmitted within a transmit time interval of the radio equipment controller; and fast-sampling, by the proxy node, the CPRI bit stream to determine whether a hyper frame number synchronization with the radio equipment controller at a common matching link bit rate is achievable, wherein the fast-sampling comprises attempting to decode the received CPRI bit stream and achieve the hyper frame number synchronization for each of a plurality of link bit rates configured for a fast-sampling time period during at least one fast-sampling time interval configured for the proxy node.