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 battery management system (BMS) is presented herein. The BMS has a master node. The master node includes a master transceiver and a controller communicably coupled to the master transceiver. The BMS has a plurality (n) of slave nodes. Each slave node of the n slave nodes includes a slave transceiver for communicably coupling to at least one battery monitor. The controller of the BMS is configured to direct the master transceiver to establish a communications network with the n slave nodes. To establish the communications network, the controller is also configured to respectively assign each of the n slave nodes to non-overlapping time slots of a superframe. The controller is further configured to direct the master transceiver to consecutively receive uplink (UL) transmissions from the n slave nodes in the non-overlapping time slots of the superframe.

A synchronization apparatus, a synchronization system, a radio communication apparatus, and a synchronization method capable of reducing the effect of the fluctuations in synchronization signals that arc caused when the synchronization signals arc received through a network are provided. A synchronization apparatus (20) according to the present invention receives a synchronization signal transmitted from a synchronization signal source (10) through a network. The synchronization apparatus (20) includes a frequency synchronization unit (21) that performs frequency synchronization based on a received synchronization signal, and outputs a frequency synchronization signal, a phase synchronization unit (23) that performs phase synchronization based on a synchronization signal transmitted from the synchronization signal source (10) through a network, and outputs a phase synchronization signal, and a phase synchronization control unit (22) that generates an offset value by using a phase difference between the frequency synchronization signal and the phase synchronization signal, and corrects a phase of the frequency synchronization signal by using the offset value.

A system for testing synchronous TTP communication networks is provided. The system includes a first and second nodes coupled to a transmission bus. The first node is configured to generate a test command, which includes a test flag and a test round field, set the test flag, and transmit the test command and a plurality of parameters via the transmission bus using data frames. The second node is configured to receive the test command and the plurality of parameters from the transmission bus, determine whether the test flag is set, and compare parameter values in the received data frames with expected values in a test vector stored on the second node, for each of the plurality of parameters, in response to determining that the test flag is set. The first and second nodes are configured to communicate with each other using a TTP on a time slot basis.

A communications network delay variation smoothing method, an apparatus, and a system are disclosed. The method includes: clearing, by a local device, a forward delay threshold and a reverse delay threshold when an initialization time starts; and when determining that a maximum value between a real-time forward delay value corresponding to a current service flow fragment and a reverse delay threshold corresponding to the current service flow fragment is greater than a current value of the forward delay threshold, replacing the current value of the forward delay threshold with the maximum value. In this way, after the initialization ends, a delay threshold after the initialization ends is determined and is applied to delay compensation, thereby significantly reducing a bi-directional asymmetric delay variation, and avoiding a problem of abnormal user communication that is caused when the variation exceeds a limit.

Certain features relate to compensating for a roundtrip delay caused by a distributed antenna system. A delay unit communicatively coupled to a base station can intercept the delay compensation signaling communicated between the digital baseband unit of the base station and the radio transmitter unit of the base station. The delay unit can adjust the delay compensation signaling by adding to the delay compensation signaling the pre-determined fiber delay caused by the DAS. In some aspects, the delay unit can delay the control words for a base station operating under the Common Public Radio Interface standard. In other aspects, the delay unit can delay the roundtrip time measurement message for a base station operating under the Open Base Station Architecture Initiative standard.

Systems and methods presented herein provide for an LTE wireless communication system operating in an RF band with a conflicting wireless system. The LTE system includes a first eNodeB operable to transmit downlink communications to UEs in the RF band and to receive uplink communications from the UEs in the RF band. The first eNodeB is also operable to transmit an LTE control channel across a portion of the RF band, to time divide the LTE control channel into a plurality of subchannels, and to occupy a first of the subchannels. A second eNodeB is operable to detect the LTE control channel and to occupy a second of the subchannels proximate in time to the first subchannel of the first eNodeB.

A system for testing synchronous TTP communication networks is provided. The system includes a first and second nodes coupled to a transmission bus. The first node is configured to generate a test command, which includes a test flag and a test round field, set the test flag, and transmit the test command and a plurality of parameters via the transmission bus using data frames. The second node is configured to receive the test command and the plurality of parameters from the transmission bus, determine whether the test flag is set, and compare parameter values in the received data frames with expected values in a test vector stored on the second node, for each of the plurality of parameters, in response to determining that the test flag is set. The first and second nodes are configured to communicate with each other using a TTP on a time slot basis.

A method and apparatus 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. The apparatus comprises a control unit configured to cause the first transceiver unit to transmit a first signal to the second transceiver unit over the first path and to receive a reply to the first signal from the second transceiver unit over the second path, and to transmit a second signal to the second transceiver unit over the second path and to receive a reply to the second signal from the second transceiver unit over the first path. The apparatus further comprises a receiving unit configured to receive a first time reference representing the time of transmission of the 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 the time of transmission of the 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. The apparatus further comprises a determining unit configured to determine a propagation delay of the first path and or of the second path using the first time reference, the second time reference, the third time reference and the fourth time reference.

Presented are systems and methods for spectrum management and timing optimization of communication networks have multiple distribution points, multiple remote transceivers, and a shared communication binder. In some embodiments, distribution points and communication lines are added to an active network by the allocation of unused time slots. In some embodiments, transmission collisions, near-end cross-talk, and far-end cross-talk, are predicted upon the addition of added distribution points and communication lines, and techniques are applied to reduce or cancel such phenomena.