Design of Coded ALOHA With ZigZag Decoder

Abstract

In this study, we investigated the effects of combining a zigzag decoder (ZD) with a coded ALOHA using the successive interference cancellation (SIC) technique to retrieve packets from collisions. We proposed zigzag decodable coded slotted ALOHA (ZDCSA) and enhanced-ZDCSA (E-ZDCSA) as a scheme which applies ZD before and after SIC, respectively. Furthermore, we derived the asymptotic analysis for the throughput and packet loss rate (PLR) performances of E-ZDCSA and validated its accuracy with the Monte Carlo simulations. Through numerical and asymptotic analyses, we showed that E-ZDCSA outperforms ZDCSA and the conventional coded ALOHA schemes in terms of throughput and PLR performances in most of the offered load regime. Moreover, we demonstrated that our proposed schemes outperform the conventional protocol in a practical scenario in which ZD cannot resolve all the collisions.

Keywords

• Slotted ALOHA
• successive interference cancellation
• ZigZag decoding