channel coding

channel coding

Encoding a communications channel to ensure error-free transmission. Channel coding modifies the outgoing message, which is known as "forward error correction" (FEC). At the receiving end, the channel coding bits are used to verify the validity of the message and correct most errors. Channel coding improves the signal-to-noise ratio (SNR).

Convolutional Codes
Convolutional codes were introduced in 1955 by Peter Elias. The input bits are transformed by predefined algorithms and decoded at the receiving end. Viterbi and BCJR are the common convolutional algorithms. See Viterbi decoder.

LDPC
Introduced by Robert Gallager in 1960 and rediscovered more than 30 years later, the low-density parity check (LDPC) method creates a block parity bit that takes little processing to decode. Also known as "Gallager codes."

Turbo Codes
Turbo codes were introduced in 1993 by Claude Berrou and were licensed by France Telecom until 2013. There are several turbo code variations; however, the primary method passes the input bits through two convolutional decoders. The two decoders exchange probabilistic information to assist each other similar to the way a turbo engine works.

Polar Codes
Polar codes were introduced in 2009 by Turkish professor Erdal Arikan. Creating a "virtual channel" that is the polar opposite of the main transmission stream, polar codes require more processing at both ends. However, they offer high performance and have been adopted by the 3GPP for the 5G New Radio (NR) control channels.
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References in periodicals archive ?
Polar codes are the world's first channel coding scheme to take the world up to the threshold of Shannon's limit, or the maximum rate that data can be sent with zero error at a particular bandwidth.
Polar codes are the world's first channel coding scheme to bring us up against the threshold of Shannon's limit, or the maximum rate that data can be sent with zero error at a particular bandwidth.
Most of existing matching algorithms were investigated based on the Continuous input Continuous output Memoryless Channel (CCMC) [32] capacity, which assumed perfect channel coding and perfect modulation.
The end-to-end 5G NR system operates at 3.5 GHz and supports a 100-MHz bandwidth, compliant with the 3GPP Release-15 5G New Radio layer 1 framework--including the scalable OFDM numerology, new advanced channel coding and modulation schemes, and the low-latency self-contained slot structure.
The end-to-end 5G NR system operates in 3.5GHz and supports 100MHz bandwidth, compliant with the 3GPP Release-15 5G New Radio layer 1 framework -- including the scalable OFDM numerology, new advanced channel coding and modulation schemes, and the low-latency self-contained slot structure.
Intel also announced its 5G modem at the Consumer Electronics Show (CES) in January, with a single chip that supports both mmWave and sub-6GHz spectrum bands, incorporating Massive MIMO, beam-forming technology, and advanced channel coding.
Berens, 'Enhanced channel coding for OFDM-based UWB systems', in IEEE International Conference.
To address this problem, we employ channel coding, which is composed of two parts: an encoder and a decoder.
Supports key 5G NR technology features, including low latency frame structure, advanced channel coding, massive MIMO and beamforming
The simulation uses Hamming (15,11) channel coding with automatic repeat request (ARQ).
Channel coding is crucial to achieve good performance in a communication system.