A user equipment device (UE) comprises physical layer circuitry configured to transmit and receive radio frequency electrical signals with one or more nodes of a radio access network, an audio subsystem configured to generate frames of audio data, and processing circuitry. The processing circuitry is configured to calculate a time delay from generation of an audio data frame by the audio subsystem of the UE device to transmission of an audio data packet by the physical layer circuitry during a voice call, and decrease the time delay to a delay value that preserves a specified minimum time for delivery of the generated audio data frame to the physical layer circuitry to meet a scheduled transmission time of the audio data packet.

In an audio processing apparatus configured to supply audio data to a processor configured to process audio data, a plurality of receivers, each configured to receive audio data and a work clock carried with the audio data and to supply the audio data to the processor; a plurality of PLL circuits corresponding to the plurality of receivers, each PLL circuit being configured to generate a clock signal based on a word clock received by the corresponding receiver; and a selector configured to select a clock signal from among a plurality of clock signals generated by the plurality of PLL circuits, and to supply the selected clock signal to the processor, the processor outputting the processed audio data at timing synchronized with the selected clock signal are provided.

One embodiment includes a system. The system includes a receiver configured to extract a timestamp from a header of each packet of a data stream received from a network and to de-packetize the data stream to provide a stream of data blocks. The timestamp can correspond to generation of each data block associated with each respective packet of the data stream according to a global timebase. The system also includes a delay controller configured to measure a delay associated with each packet of the data stream based on the timestamp relative to the global timebase and to control converting the data stream to a corresponding analog output signal for transmission based on the measured delay.

Systems, methods, and computer-readable media for processing a digital bit stream representative of a communication signal are provided. The method can include dividing, at one or more processors, the digital bit stream into a plurality of data packets, each having an overlap of data from an adjacent packet. The method can include performing a timing recovery operation and a carrier recovery operation on portions of the plurality of data packets in multiple processing blocks in the processor, in parallel. The method can include combining the first plurality and the second plurality based on timing and phase stitching.

Control apparatus to control operation of a data buffer to which data items are written according to a write pointer which advances in position in response to an input data item rate and from which data items are read according to a read pointer which advances in position in response to an output data item rate, comprises: a detector configured to detect an occupancy difference between a current buffer occupancy and a target buffer occupancy, in which the current buffer occupancy represents a difference between the read and write pointers; an output data item interpolator configured to interpolate a data item at an interpolated data buffer location displaced by a read offset displacement from a data buffer location pointed to by the read pointer; and output control circuitry configured, in response to a current occupancy difference exceeding a threshold occupancy difference, to change the read pointer from an initial read pointer to a target read pointer by a change amount so as to reduce the occupancy difference, the output control circuitry being configured to progressively vary the read offset displacement so as to define an interpolated data buffer location which progresses over the output of a transitional group of data items towards the location pointed to by the target read pointer; the output control circuitry being further configured, when the occupancy difference is less than the threshold occupancy difference and the interpolated data buffer location is aligned with the target read pointer, to inhibit operation of the output data item interpolator and to control output of an output data item from the data buffer location pointed to by the read pointer.

This application provides a method for sending and receiving a clock synchronization packet in FlexE. The method includes: generating, by a sending apparatus, indication information and a plurality of data blocks, where the plurality of data blocks are obtained by encoding a first clock synchronization packet, the indication information is used to indicate a first data block, and the first data block is a data block used for timestamp sampling in the plurality of data blocks; determining, by the sending apparatus, according to the indication information, a moment at which the first data block arrives at a medium dependent interface MDI of the sending apparatus, and generating a sending timestamp, where the sending timestamp is used to record a sending moment of the first clock synchronization packet; generating a second clock synchronization packet carrying the sending timestamp; and sending, by the sending apparatus, the second clock synchronization packet.

Some disclosed systems and methods include assigning channel streams to satellite playback devices, delaying initial transmission of surround sound content to satellite playback devices to accumulate audio samples for transmission in individual frames of surround sound content, and taking advantage of configured playback delays for different channels of surround sound content to prioritize transmission of channels of surround sound content having shorter configured playback delays over transmission of channels of surround sound content having longer configured playback delays.

A wireless conference system includes an access point and a plurality of conference units, configured for bi-directional, TDMA based wireless communication of latency sensitive audio data packets. The access point and conference units include clocks actively synchronized, generating local audio clock signals used for processing the audio data packets and local synchronization clock signals used for the TDMA based wireless communication. The conference units and access point have a transceiver. The receiver includes a packet loss detection unit configured to detect loss of an audio data packet and including: means to determine an expected arrival time for an audio data packet from the local synchronization clock signal and from a predetermined expected transmission delay, and means to detect whether the audio data packet is lost. The receiver further includes a packet loss concealment unit configured to generate a replacement packet for a lost audio data packet.

A network element includes at least two Time Division Multiplexing (TDM) modules each including a TDM client interface, TDM processing circuitry, and circuit emulation circuitry; and a packet switch fabric connected to the at least two TDM modules in a Link Aggregation Group (LAG) for a protected TDM service, and configured to output a packet interface, wherein the protected TDM service is provided as a single packetized TDM stream via the packet interface from the packet switch fabric.

A networked system is provided for transporting digital media packets, such as audio and video. The network includes network devices interconnected to send and receive packets. Each network device can receive and transmit media signals from media devices. A master clock generates a system time signal that the network devices use, together with a network time protocol to generate a local clock signal synchronised to the system time signal for both rate and offset. The local clock signal governs both the rate and offset of the received or transmitted media signals. The system, which can be implemented using conventional network equipment enables media signals to be transported to meet quality and timing requirements for high quality audio and video reproduction.