In a method for generating a data unit for transmission via a communication channel, the data unit conforming to a first communication protocol, one or more orthogonal frequency division multiplexing (OFDM) symbols of the data unit are generated. Each OFDM symbol of the one or more OFDM symbols (i) occupies a first bandwidth, (ii) is generated with a first tone spacing, and (iii) includes a set of pilot tones. The first tone spacing is a fraction 1/N of a second tone spacing, the second tone spacing defined for the first bandwidth by a second communication protocol. The set of pilot tones includes a same number of pilot tones as defined for the first bandwidth by the second communication protocol. The data unit is generated to include the one or more OFDM symbols in a data portion of the data unit.

A non-systematic convolutional decoder of a convolutionally encoded multi-level data stream includes a shift register and two or more paths of exclusive-OR (XOR) gates, arranged to reconstruct an original input information stream, each path having a quantiser arranged to quantise the signal to two levels, and a set of XOR gates arranged to match an encoding path in an associated convolutional encoder, and a selector arranged to feed an output from each path to a single input of the shift register. If the paths have differing values at their output, the selector may choose the value from the path based upon a function of the multi-level signals associated with each path, such as the path with the largest absolute signal level. The decoder provides a simple means for decoding signals while allowing the signal to also or instead be decoded using e.g. a Viterbi decoder if higher performance is required.

Devices, systems and methods for list decoding of polarization-adjusted convolutional (PAC) codes are described. One example method for improving error correction in a decoder for data in a communication channel includes receiving a noisy codeword, the codeword having been generated using a polarization-adjusted convolutional (PAC) code and provided to the communication channel prior to reception by the decoder, and performing PAC list decoding on the noisy codeword, wherein an encoding operation of the PAC code comprises a convolutional precoding operation that generates one or more dynamically frozen bits, and wherein the PAC list decoding comprises extending, based on the one or more dynamically frozen bits, at least two paths of a plurality of paths in the PAC list decoding differently and independently.

A wireless local area network (WLAN) transmitter includes a baseband processing module and a plurality of radio frequency (RF) transmitters. The processing module selects one of a plurality of modes of operation based on a mode selection signal. The processing module determines a number of transmit streams based on the mode selection signal. The processing of the data further continues by converting encoded data into streams of symbols in accordance with the number of transmit streams and the mode selection signal. A number of the plurality of RF transmitters are enabled based on the mode selection signal to convert a corresponding one of the streams of symbols into a corresponding RF signal such that a corresponding number of RF signals is produced.

A method of fast link adaptation for Bluetooth long-range wireless networks is provided. A data packet comprises a preamble, a first packet portion including a rate indication field, and a second packet portion including a PDU. The first packet portion is encoded using a first modulation and coding scheme with a first rate while the second packet portion is encoded using a second modulation and coding scheme with a second rate indicated by the RI field. A transmitter thus can use different MCS options to support variable data rates by adapting to channel conditions, and then uses the novel RI field to indicate the data rate to a receiver dynamically. As a result, fast link adaptation can be achieved for different applications with different rate requirements, to provide higher data rate, reduce connection time, lower power consumption, and improve link quality.

The present disclosure relates to a pre-5th-generation (5G) or 5G communication system to be provided for supporting higher data rates beyond 4th-generation (4G) communication system such as a long term evolution (LTE). A method for receiving data includes selecting one of reception schemes, and receiving data based on the selected reception scheme, wherein the reception schemes includes a scheme of determining an integer matrix based on channel values estimated for channels, and decoding symbols received through the channels based on the determined integer matrix, and a scheme of detecting, for each channel, a sum of symbols received from each of the channels during a preset time based on integer matrixes which are determined based on each of the channel values, retransforming the sum of the symbols detected for each channel based on at least one of the integer matrixes, and decoding the retransformed sum of the symbols for each channel.

An apparatus and method for time interleaving corresponding to hybrid time interleaving mode are disclosed. An apparatus for time interleaving according to an embodiment of the present invention includes a twisted block interleaver configured to perform intra-subframe interleaving corresponding to time interleaving blocks; and a convolutional delay line configured to perform inter-subframe interleaving using an output of the twisted block interleaver.

Methods and apparatuses for encoding and decoding a physical layer (PHY) protocol data unit (PPDU) for low power indoor (LPI) wireless communication, which includes a preamble portion and a payload portion. The preamble portion includes a first universal signal field (U-SIG), the first U-SIG comprising information regarding a payload portion of the PPDU. The preamble portion further includes a second U-SIG, which contains identical information regarding the payload portion of the PPDU. The repetition of the U-SIG may improve robustness of the preamble portion detection and also enable auto-detection of the PPDU for LPI communication.

An Acknowledgment (ACK) method is provided by a receiving device in a Wireless Local Area Network (WLAN). The receiving device receives a plurality of data units having a plurality of Traffic Identifiers (TIDs) and transmits an ACK frame including a plurality of ACK information fields for at least part of the plurality of data units. An ACK information field for a data unit satisfying a first condition among the plurality of ACK information fields includes a Traffic Identifier (TID) and a block ACK bitmap indicating whether the data unit has been successfully received. An ACK information field for a data unit satisfying a second condition and having been successfully received among the plurality of ACK information fields includes the first TID and does not include a block ACK bitmap.

A technique for assessing the reliability of bits received by a modulation symbol on a channel is provided. A providing circuit provides an input dataset including a plurality of input values. The input values correspond to different transmit hypotheses according to a modulation alphabet used for encoding the bits in the symbol. A computing circuit performs a first computing step and a second computing step. In the first computing step, a first intermediary dataset is computed by combining the input values of the input dataset according to a first combination scheme. In the second computing step, a second intermediary dataset is computed by combining the input values of the input dataset according to a second combination scheme. The second combination scheme is different from the first combination scheme. An assessing circuit assesses the reliability of the bits based on the first intermediary dataset and the second intermediary dataset.