Aspects of the present disclosure relate to retransmissions of data within wireless communication networks. For a retransmission, at least a portion of the encoded bits of an original transmission may be mapped to different bit locations in one or more modulated symbols based on a non-random mapping rule. In some examples, the encoded bits of a symbol may be reversed within the symbol for a retransmission. In other examples, the first and last encoded bits within a symbol may be switched for a retransmission. Other non-random mapping rules, such as a bit location offset, may also be used to map encoded bits to different bit locations in the modulated symbol within a retransmission.

A method and a device for transmitting and receiving data in a wireless communication system are disclosed. In an embodiment the method includes receiving transmission data, dividing the received transmission data into K>1 data streams, where K is a positive integer, feeding each data stream into its associated parallel processing path so as to obtain K modulated data packets j=1, . . . , K from the parallel processing paths, wherein in each processing path the method further includes segmenting the data stream, encoding the segmented data stream with a first error detection code and modulating the error detection encoded segmented data stream so as to obtain a modulated data packet j comprising a plurality of modulated symbols. The method further includes multiplexing the K modulated data packets so that at least one modulated symbol of each modulated data packet j are placed in proximity to each other in time and/or frequency.

A forward error correction (FEC) data generator has an input for at least two datastreams for which FEC data shall be generated in a joint manner, each datastream having a plurality of symbols. A FEC data symbol is based on a FEC source block possibly having a subset of symbols of the at least two data streams. The FEC data generator further has a signaling information generator configured to generate signaling information for the FEC data symbol regarding which symbols within the at least two datastreams belong to the corresponding source block by determining pointers to start symbols within a first and a second datastream, respectively, of the at least two datastreams and a number of symbols within the first datastream and second datastreams, respectively, that belong to the corresponding source block.

A method and apparatus for transmitting a streaming media with Forward Error Correction (FEC). Upon receiving the streaming media, the technique includes: encoding, segmenting and packeting frames comprised therein to generate a packetized elementary stream of media packets with variable sizes; for each L sequential media packets, calculating a random loss (RL) FEC parity and generating a respective RL FEC packet associated therewith; calculating burst loss (BL) FEC parities in accordance with a predefined FEC scheme and generating respective BL FEC structures bearing FEC headers and usable for generating BL FEC packets; calculating size-related parameters of a group of sequential media packets, the group being selected in accordance with the FEC scheme; and, transmitting the packetized elementary stream with interleaved FEC packets. The BL FEC packets are transmitted merely when the calculated size-related parameters meet a size-related burst loss (SRB) criterion defined by the FEC scheme.

A method of transmitting data by a transmitter in a broadcast system, a transmission device for transmitting at least one data stream in a broadcast system, a method of receiving data by a receiver in a broadcast system, and a receiving device for receiving data in a broadcast system are provided. The method of transmitting data by a transmission device includes generating a first frame including a preamble and a payload, wherein the preamble comprises first information related to the payload of the first frame and the payload comprises the data; and transmitting the first frame, wherein the preamble includes at least one parity bit for third information related to a payload of a second frame, wherein the second frame is a next frame of the first frame, and wherein the preamble of the first frame comprises second information related to the first information.

An adaptive downlink control channel structure is provided to enable a transmitter to switch between forward error correction codes that use either Chase combining or incremental redundancy hybrid automatic repeat request (HARQ) techniques. Chase combining HARQ can be more efficient for forward error correction codes that use higher code rates, while incremental redundancy can be more effective for forward error correction codes that use lower code rates. The transmitter will also selectively comprise the redundancy version indicator bits depending on the HARQ method selected, which can reduce the sizes of the transport blocks when not using incremental redundancy. A receiver device can also decode transport blocks and determine whether a redundancy version indicator is present based on the forward error correction code selected.

Disclosed herein are systems and methods for forward packet recovery in a communication network with constrained network bandwidth overhead. In exemplary embodiments, a target byte protection ratio is determined. Error correcting frames are dynamically generated by a first processor such that error correcting information can be generated to approximate the target byte protection ratio. The data packets and error correcting information are then transmitted across one or more communication networks to a second processor. The second processor can use the error correcting information to regenerate or replace data packets missing or corrupted in transmission across one or more communication networks.

Embodiments of the present invention relate to a data transmission method and apparatus based on unequal error protection and a device. The method includes: segmenting, according to a quantity of symbol bits in a constellation diagram, a code block corresponding to data, to obtain segmented code blocks; performing rate matching on the segmented code blocks obtained by channel encoding, to obtain output code blocks; cascading the output code blocks according to the quantity of symbol bits in the constellation diagram, to obtain cascaded code blocks; and sending the cascaded code blocks to a terminal device.

Disclosed herein is method and device for performing a Hybrid Automatic Repeat request (HARQ) based on polar codes in a wireless communication system. A transmitter transmits a first packet to a receiver. The transmitter receives a re-transmission request for the first packet from the receiver. The transmitter transmits a second packet to the receiver. Herein, each of the first packet and the second packet includes at least one information bit and at least one frozen bit. An information bit having a smallest mutual information corresponding to a bit channel within the first packet is re-transmitted through a first bit channel capable of transmitting at least one information bit included in the second packet. Alternatively, a new information bit is transmitted through a second bit channel capable of transmitting at least one information bit included in the second packet.

Systems and methods for reducing communication latency are provided. A communication session with a remote device is initiated. One or more message packets are transmitted to the remote device. Subsequently, it is determined whether any additional message packet is scheduled to be transmitted to the remote device. In the event that no additional message packet is scheduled to be sent to the remote device, a loss detection packet is appended to a last message packet. The last message packet and the loss detection packet are transmitted to the remote device. It is further determined whether the last message packet was successfully received by the remote device based on receipt of an acknowledgment message. In the event that the last message packet was not successfully transmitted, a retransmit of the last message packet is executed.