Write-Once Memory codes for low-complexity decoding of Asymmetric Multiple Access Channel

Write-Once Memory (WOM) codes are designed for data storage, which allow re-writing on n cells that can change their bit value from 0 to 1 but not vice versa. This paper focuses on applying “WOM codes” to cooperative wireless communications. Due to the characteristics of WOM codes, the Asymmetric Multiple Access Channel (AMAC) (also referred to as the MAC with degraded messages) is considered, which is a conventional Multiple Access Channel (MAC), where one user can observe the other user´s message. We describe an AMAC system where WOM codes are used to deal with the interference between two users. For a specific AMAC model, WOM codes can achieve the AMAC capacity, and using WOM codes for the AMAC with no errors leads to a low-complexity decoder. Finally, we comment of how the AMAC model can be applied to the relay channel. While we consider primarily the AMAC with no errors, this study forms a foundation for future work on the AMAC with errors.