Compute-Forward Multiple Access (CFMA): Practical Implementations

We present a practical strategy that aims to attain rate points on the dominant face of the multiple access channel capacity using a standard low complexity decoder. This technique is built upon recent theoretical developments of Zhu and Gastpar on compute-forward multiple access which achieves the...

Descripción completa

Detalles Bibliográficos
Autores: Sula, E, Zhu, JG, Pastore, A, Lim, SH, Gastpar, M
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2019
País:España
Institución:Centre Tecnològic de Telecomunicacions de Catalunya (CTTC)
Repositorio:r-CTTC. Repositorio Institucional Producción Científica del Centre Tecnològic de Telecomunicacions de Catalunya (CTTC)
OAI Identifier:oai:cttc.fundanetsuite.com:p1457
Acceso en línea:https://cttc.fundanetsuite.com/Publicaciones/ProdCientif/PublicacionFrw.aspx?id=1457
https://www.scopus.com/inward/record.uri?eid=2-s2.0-85054543828&doi=10.1109%2fTCOMM.2018.2874240&partnerID=40&md5=8f082c177a13aa448bc87ac193862784
Access Level:acceso abierto
Palabra clave:Channel capacity
Channel coding
Decoding
Receivers (containers)
Recovery
Satellite communication systems
Signal encoding
Signal interference
Standards
Complexity theory
Face
Interference channels
Low-density parity-check (LDPC) codes
Multiple access
Multiple access channels
Parity check codes
Sequential decoding
Sum-product algorithm
Multiple access interference
Descripción
Sumario:We present a practical strategy that aims to attain rate points on the dominant face of the multiple access channel capacity using a standard low complexity decoder. This technique is built upon recent theoretical developments of Zhu and Gastpar on compute-forward multiple access which achieves the capacity of the multiple access channel using a sequential decoder. We illustrate this strategy with off-the-shelf LDPC codes. In the first stage of decoding, the receiver first recovers a linear combination of the transmitted codewords using the sum-product algorithm (SPA). In the second stage, by using the recovered sum-of-codewords as side information, the receiver recovers one of the two codewords using a modified SPA, ultimately recovering both codewords. The main benefit of recovering the sum-of-codewords instead of the codeword itself is that it allows to attain points on the dominant face of the multiple access channel capacity without the need of rate-splitting or time sharing while maintaining a low complexity in the order of a standard point-to-point decoder. This property is also shown to be crucial for some applications, e.g., interference channels. For all the simulations with single-layer binary codes, our proposed practical strategy is shown to be within 1.7 dB of the theoretical limits, without explicit optimization on the off-the-self LDPC codes. © 1972-2012 IEEE.