Spectral efficiency of a non-orthogonal FH-CDMA system

Author(s)

de Miranda Marques, Daniel Hindemburg ^[1] ; Sharma, Manish ^[2]

Affiliation

^[1] Agencia Nacl Telecomunicacoes, Rua Vergueiro 3073 Vila Mariana, BR-01101300 Sao Paulo - Brazil

^[2] Inst Tecnol Aeronaut, Praca Marechal Eduardo Gomes 50 Vila Acacias, BR-12228900 Sao Jose Dos Campos - Brazil

• Document type: Journal article
• Source: IET COMMUNICATIONS; v. 14, n. 21, p. 3927-3933, DEC 22 2020.
• Web of Science Citations: 0

Abstract

Fast frequency hopping code division multiple access (FH-CDMA) is a low complexity option for multiuser communication in fast, frequency selective fading channels such as in mobile mmWave communications. The original, orthogonal FH-CDMA has low spectral efficiency and up to now lacks a non-orthogonal version. In this work, a soft input soft output, non-orthogonal multiuser detector is designed using factor graphs. Extrinsic Information Transfer (EXIT) chart analysis of this detector allows determination of which multiple access code length maximises system spectral efficiency. Results show that when the access code length is reduced to an ideal length, spectral efficiency is maximised. Another conclusion is that maximum spectral efficiency is similar in value to a system with no multiple access method. (AU)

• FAPESP's process: 13/25977-7 - Security and reliability of Information: theory and practice
• Grantee: Marcelo Firer
• Support Opportunities: Research Projects - Thematic Grants