Random Packet CDMA: Reducing Delay and Increasing Throughput of WLAN Systems Roland Kempter and Behrouz Farhang-Boroujeny Department of Electrical and Computer Engineering, University of Utah, USA Abstract— We revisit Random Packet Code Division Multiple Access (RP-CDMA), a recently proposed Physical/MAC layer scheme for wireless CDMA networks. We revise earlier results by adopting a more reali...

Reservation frame slotted-ALOHA (RFSA) was proposed in the past to manage the access to the wireless channel when devices generate long messages fragmented into small packets. In this paper, we consider an M2M area network composed of end-devices that periodically respond to the requests from a gateway with the transmission of fragmented messages. The idle network is suddenly set into saturatio...

of this work is to assess the impact of such MU detecPacketized random access based on Code Division Multiple Access (CDMA) is considered. Our primary aim is to assess the impact of (uncoded) multi-user (MU) detectors on the performance of CDMA with slotted ALOHA. The impact of respective multiple packet reception capability for the matched filter and MMSE detector on delay/throughput improveme...

One of the main problems in WIMAX is to share the medium by multiple users who compete for access. Various random access mechanisms, such as ALOHA and its corresponding variations have been widely studied as efficient methods to coordinate the medium access among competing users. In this paper the slotted ALOHA protocol is implemented as a two-state system. Using Markov Models, we evaluate the ...

New hierarchical protocols, SRMA-ALOHA and SRMA-Poll, are proposed for multiple random-access in wide area satellite data networks. The stations are grouped and operate in ALOHA or Poll mode, and group master stations access the channel using the SRMA scheme. The performance of protocols has been evaluated using simulations. Throughput and delays are presented for various traffic load condition...

We propose and analyse three different power selection schemes for slotted ALOHA random access protocol operating under multiple power levels. Through analysis and numerical examples we demonstrate that these schemes can significantly improve the performance of slotted ALOHA, in terms of throughput and stability, under heavy load. The proposed schemes are truly distributive in nature and can be...

Ad-hoc networking, though an attractive solution for many applications, still presents many unsolved issues, such as the hidden-terminal problem, flexible and prompt access, QoS provisioning, and efficient broadcast service. In this paper we present a MAC architecture able to solve the above issues in environments with no power consumption limitation, such as networks for inter-vehicle communic...

Radio Frequency Identification (RFID) technology is one of the most promising technologies in the IoT (The Internet of Things) era. Many RFID systems have been used in supermarkets or warehouses. There are two challenges for RFID anti-collision algorithms. The first challenge is accurately estimating the number of tags; the other is improving the efficiency of RFID systems. This paper proposes ...

In this paper, we have investigated the performance of a multicell S-ALOHA DSCDMA system with fast power control error on a Nakagami frequency selective environment. We analyzed how the throughput of the optimally stabilized system is affected by the channel conditions and some key system characteristics such as the processing gain or the number of fingers in the RAKE receiver. By using an idea...

We consider the channel aware slotted ALOHA protocol that has been recently proposed to improve the capacity of the traditional slotted ALOHA by using multi-user diversity. This type of diversity is commonly used in scheduling policies that allow terminals to transmit when their channel conditions are good. Here, we focus on a decentralized random access protocol where users decide to transmit ...