Telefonaktiebolaget Lm Ericsson (publ)

Stefano Stracca

Fabio Cavaliere

Stefano Ruffini

Giulio Bottari

Paola Iovanna

Paolo Debenedetti

Tomas Thyni

Mats Forsman

Filippo Ponzini

Luca Giorgi

Roberto Sabella

Mats Johansson

Alessandra Bigongiari

Methods and apparatus are provided for transmitting synchronization data over a FlexE communications link. In an example aspect, a method of transmitting synchronization data over a FlexE communications link includes, in response to a synchronization event, selecting a next slot of the FlexE communications link that is unallocated or is allocated to a FlexE client, and transmitting synchronization data associated with the synchronization event in the selected slot.

Transmitting and receiving synchronization data

Methods and apparatus are provided for transmitting data. In one aspect, a method of transmitting data comprises identifying a start of a Common Public Radio Interface (CPRI) frame, identifying CPRI data blocks of the CPRI frame, and transmitting the CPRI data blocks of the CPRI frame in slots of a FlexE calendar of a Flex Ethernet physical layer group (FlexE PHY group).

CPRI data block transmission method and apparatus

A method of supporting latency monitoring in a network transporting traffic to and from a wireless base station. The method comprises, at a first node of the transport network determining a first timestamp representing a time at which a data element is received at the first node and adding information representative of the first timestamp to a communication signal which carries data for the wireless base station, the data including the data element. The method also comprises sending an indication of an association between the information representative of the first timestamp and the data element that the information representative of the first timestamp relates to. A method performed at a second node as well as apparatus for use at the first node and apparatus for use at the second node are also disclosed.

Method and apparatus for latency monitoring

The disclosure provides methods, apparatus and computer-readable media for synchronization over an optical network. A method comprises: receiving, from a client, a request to initiate a synchronization service for a client node coupled to the optical communication network; and, in response to the request, establishing a synchronization service to the client node via a virtual synchronization network utilizing the optical communication network. The synchronization service utilizes a bidirectional optical channel established via the optical communication network for the transmission of synchronization data for the client.

Methods, apparatus and computer-readable media for synchronization over an optical network

A method of managing transport of packets transmitted over a time division multiplexed, TDM, link in a network. The method performed at a second network node comprises: receiving () blocks of data from a first network node. Data from one packet is received in a plurality of blocks and a first block from a packet has a time-stamp indicating arrival time of the packet at the first network node. The blocks are multiplexed for transmission over the TDM link. The method also comprises: queuing () the received blocks and if a block from the top of the queue () has a time-stamp (&#x2014;yes) and a maximum allowed latency has been exceeded () the method discards () blocks containing data from the same packet as the block with said time-stamp if there is at least one block containing data from another packet in the queue (&#x2014;yes). An apparatus is also disclosed.

Method and apparatus for managing transport of delay-sensitive packets

A method of supporting latency monitoring in a network transporting traffic to and from a wireless base station. The method comprises, at a first node of the transport network determining () a first timestamp representing a time at which a data element is received at the first node and adding () information representative of the first timestamp to a communication signal which carries data for the wireless base station, the data including the data element. The method also comprises sending () an indication of an association between the information representative of the first timestamp and the data element that the information representative of the first timestamp relates to. A method performed at a second node as well as apparatus for use at the first node and apparatus for use at the second node are also disclosed.

A method for managing traffic of a plurality of packets in a plurality of packet flows transmitted using a time-slotted interface. The packet flows traverse a plurality of switches of a transport network according to an assigned path from a source node to a destination node. The method comprises determining an end-to-end latency of a plurality of packets traversing a current switch in packet flows and assigning priority values to the packets traversing the current switch, wherein a priority value of a packet depends on the determined end-to-end latency of said packets. The method further comprises allocating a time slot in an output interface of the current switch to the packet having the highest priority value among the packets competing for said time slot.

Method and switch for managing traffic in transport network

A method for switching data signals transmitted over a transport network is disclosed. The method comprises receiving a plurality of input data signals of a first signal type wherein the plurality of data signals of the first signal type comprises data signals exchanged between a Radio Equipment and a Radio Equipment Controller and aggregating the plurality of input data signals into an aggregated first data signal. The method also comprises receiving a second data signal of a second signal type different to the first signal type, and multiplexing the first data signal with the second data signal to form a combined data signal. The method further comprises forwarding the combined data signal to the transport network. Multiplexing the first data signal with the second data signal comprises, for a frame of the combined data signal, allocating the first data signal to a portion of the frame reserved for the first data signal, and allocating the second data signal to a remaining portion of the frame.

Switching data signals of at least two types for transmission over a transport network providing both backhaul and fronthaul (Xhaul) connectivity

A transport network () is connected to a first wireless base station () and to a second wireless base station (). The first wireless base station comprises a remote radio unit () and a baseband processing unit () which are connected by the transport network (). A node () of the transport network () receives a synchronous time division multiplexed communication signal which carries at least a first communication signal between the baseband processing unit () and the remote radio unit (). The node () determines a frequency synchronisation signal from the synchronous time division multiplexed communication signal. The node () transmits the synchronous time division multiplexed communication signal to the remote radio unit () of the first wireless base station. The node () transmits the frequency synchronisation signal to the second wireless base station (). The node () also assists with providing phase/time synchronisation to the second wireless base station ().

Synchronisation of wireless base stations

A method for managing traffic of a plurality of packets in a plurality of packet flows transmitted using a time-slotted interface. The packet flows traverse a plurality of switches of a transport network according to an assigned path from a source node to a destination node. The method comprises determining () an end-to-end latency of a plurality of packets traversing a current switch in packet flows and assigning () priority to packets to the packets traversing the current switch, wherein a priority value of a packet depends on the determined end-to-end latency of said packets. The method further comprises allocating () a time slot in an output interface of the current switch to the packet having the highest priority value among the packets competing for said time slot.

Techniques are disclosed for determining propagation delay of a first path and or of a second path which connect a first transceiver unit associated with a first clock to a second transceiver unit associated with a second clock in a communications network, based on a first time reference representing a time of transmission of a first signal from the first transceiver unit, a second time reference representing the time of receipt of the first signal at the second transceiver unit, a third time reference representing a time of transmission of a reply to the second signal from the second transceiver unit, and a fourth time reference representing the time of receipt of the reply to the second signal at the first transceiver unit.

Method and apparatus for determining propagation delay in a communications network

A method () of encapsulating digital communications signals for transmission on a communications link, comprising steps: a. receiving a first signal of a first signal type and comprising a first clock signal and receiving a second signal of a second signal type, different to the first, and comprising a second clock signal different to the first clock signal, each clock signal having a respective clock value and accuracy (); b. obtaining the first clock signal (); c. obtaining a difference between at least one of the clock values of the clock signals and the accuracies of the clock signals () and buffering the second signal for a time at least long enough to compensate for the difference (); and d. assembling the first signal and the buffered second signal into a frame comprising an overhead and a payload comprising a first portion and a second portion, mapping the first signal into the first portion and the second signal into the second portion (), wherein step d. is performed using the first clock signal.

Encapsulating digital communications signals for transmission on an optical link

A network node () for a radio access network, wherein the network node comprises a switch system () configured to switch traffic for a plurality of base stations () of the radio access network. The switch system () is configured to provide for communication between a remote radio unit () and a baseband processing unit () of the said plurality of base stations. The switch system () is configured to provide for communication between a first base station () and a second base station () of said plurality of base stations. At least one of the first or second base station is a radio base station () comprising baseband processing.

Growing community of inventors

Pisa, Italy

Stefano Stracca