An optical network receiver (ONU) circuit associated with a passive optical network (PON) is disclosed. The ONU circuit comprises one or more processors is configured to operate in a hunt state, wherein the one or more processors is configured to detect frame boundaries associated with an incoming data signal based on a detecting a predefined synchronization (psync) pattern associated with the incoming data signal and transition to a pre-sync state, when the predefined psync pattern is detected correctly. The one or more processors is further configured to operate in the pre-sync state, wherein the one or more processors is configured to perform forward error correction (FEC) decoding for the incoming data signal, in order to determine signal statistics associated with the incoming data signal.

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.

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.

The present disclosure relates to a method for determining an availability of a synchronization source in a communication system. The method comprises: detecting a stability of the synchronization source when the synchronization source recovers from a failure; and determining the availability of a synchronization source based on the detected stability of the synchronization source. The present disclosure also relates to network devices and a computer readable medium for performing said method.

An optical network receiver (ONU) circuit associated with a passive optical network (PON) is disclosed. The ONU circuit comprises one or more processors is configured to operate in a hunt state, wherein the one or more processors is configured to detect frame boundaries associated with an incoming data signal based on a detecting a predefined synchronization (psync) pattern associated with the incoming data signal and transition to a pre-sync state, when the predefined psync pattern is detected correctly. The one or more processors is further configured to operate in the pre-sync state, wherein the one or more processors is configured to perform forward error correction (FEC) decoding for the incoming data signal, in order to determine signal statistics associated with the incoming data signal.

An ONU is provided. The ONU comprises a receiver configured to receive a first PON frame from an OLT, the first PON frame comprising a first PSBd field, the first PSBd field comprising a first PSync field, the first PSync field comprising first bits, and a first quantity of the first bits being greater than 64 bits; and a processor coupled to the receiver and configured to perform synchronization of the first PON frame by matching the first bits to a pre-stored sequence.

Methods and apparatus for emulating optical modules. A method includes receiving, from an optical module emulator, a first serial data stream having the plurality of upstream signals multiplexed into a plurality of bits; wherein the first data stream includes a plurality of frames, each frame having a multi-frame alignment bit; and de-multiplexing the plurality of upstream signals based on each multi-frame alignment bit within each respective frame. A method includes receiving, from an emulator controller, a second serial data stream having a plurality of downstream signals multiplexed into a plurality of bits; wherein the second serial data stream includes a plurality of frames, each frame having a multi-frame alignment bit; and de-multiplexing the plurality of downstream signals based on each multi-frame alignment bit within each respective frame.

A processing module for a receiver device. The processor module comprises a channel estimate generation component arranged to output channel estimate information for a received signal, and a timestamping module arranged to determine a ToA measurement for a marker within a packet of the received signal based at least partly on the channel estimate information for the received signal generated by the channel estimate generation component. The channel estimate generation component comprises a validation component arranged to derive a validation pattern for the packet within the received signal for which a ToA measurement is to be determined, identify a section of the packet containing a validation sequence, and perform cross-correlation between at least a part of the validation sequence within the packet and at least a part of the generated validation pattern to generate channel estimate validation information.

Techniques that provide link auto-negotiation between a radio equipment controller (REC) and a radio equipment (RE) are described herein. In one embodiment, a method includes performing, by a proxy master, a Common Public Radio Interface (CPRI) Layer 1 (L1) link auto-negotiation with a RE to achieve a L1 synchronization between the proxy master and the RE at a link bit rate; communicating the link bit rate from the proxy master to a proxy slave; performing, by the proxy slave, a CPRI L1 link auto-negotiation with a REC to determine whether a L1 synchronization between the proxy slave and the REC is achieved, wherein if the L1 synchronization is achieved, the link bit rate is a common matching link bit rate achieved; and upon the common matching link bit rate being achieved, establishing a CPRI link between the REC and the RE using the common matching link bit rate.