Slotted ALOHA performance for FU-FB in frequency selective fading environment

Abstract

Slotted ALOHA is a simple and straightforward random multiple access technique, which has been used extensively in data and cellular networks as the protocol for random access. The complexity of state space-based analysis methods for finite user finite buffer systems increases exponentially with buffer size and number of users. The presence of multipath frequency selective fading channel further adds to the complexity, making the analysis practically intractable. This paper uses an approximate analysis technique called tagged user analysis (TUA) to analyze the performance parameters of slotted ALOHA over multipath and frequency selective fading channels for finite user finite buffer systems. In TUA, the steady state system performance is evaluated from the analysis of a single user. Moreover, the state flow graph of TUA has just four states, thus reducing the complexity of the analysis. Simulation results confirm the validity of the TUA analysis.S-ALOHA performance for FU-FB in freq. sel. fading environment protocols. Access network (infrastructure mode in WiFi) is an important application where multiple users compete for the opportunity to transmit data to an access point [4]. Recent work by [5] investigated the existing S-ALOHA medium access control protocol and suggested some improvements for handling the large propagation delays involved in underwater sensor networks. Theoretical analysis of pure ALOHA and an intuitive explanation of S-ALOHA performance for ultra-wideband were presented in [6]. In [7], researchers studied S-ALOHA-based radio frequency identification system. The analytical results for finding the optimum retransmission probabilities considering S-ALOHA random access protocol with a Poisson arrival process more suitable for the traffic model in a cellular system for the users in the cells were presented in [8]. Cognitive medium access control using S-ALOHA for CR networks was investigated in [9]. S-ALOHA has also been used in other applications including wireless relay networks [10], multi-input multi-output systems [11], wireless mesh networks [12], cooperative transmission [13], framed S-ALOHA-based radio frequency identification systems [14], and wireless sensor networks [15] .The analysis of any wireless communication system entails evaluating a number of system parameters such as, blocking probability, channel throughput, packet drop probability, packet response time, and packet wait delay. The existing MA analysis methods fall in three classes-S-G analysis, Markov analysis, and equilibrium point analysis (EPA) [16]. S-G analysis assumes infinite population, which generates an aggregate traffic of S packets/slot.