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Analytical calculation of throughput of ALOHA based protocols in optical wireless data networks

IEE PROCEEDINGS-OPTOELECTRONICS 2000年第4期147卷 322-328页

作者： Samaras, K O'Brien, DC Edwards, DJ Lucent Technol Bell Labs Unit 1 Swindon SN5 7YT Wilts England Univ Oxford Dept Engn Sci Oxford OX1 3PJ England

An analytical framework for the calculation of the throughput performance of random-access protocols based on ALOHA is presented under blockage conditions in optical wireless data networks. A simple approximate Markovian channel model, which describes the channel variability, is proposed. Based on that, an analytical technique is developed for the calculation of the throughput of S-ALOHA paired with a general backoff-retransmission policy. It is shown that this combination can provide stabilised throughput performance under adverse blockage conditions. Calculation of the throughput for reservation ALOHA under the same channel conditions is described. The analytical techniques described are based on equilibrium-point analysis and their predictions are in very good agreement with Monte-Carlo-simulation results.

关键词： Monte-Carlo-simulation results Computer communications approximate Markovian channel model Information theory access protocols general backoff-retransmission policy blockage conditions adverse blockage conditions channel variability Local area networks optical wireless data networks equilibrium-point analysis ALOHA based protocol throughput S-ALOHA Optical fibre networks optical fibre LAN random-access protocols protocols telecommunication channels analytical calculation

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Tree-Algorithms With Multi-Packet Reception and Successive Interference Cancellation

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IEEE TRANSACTIONS ON COMMUNICATIONS 2023年第11期71卷 6287-6300页

作者： Stefanovic, Cedomir Deshpande, Yash Gursu, H. Murat Kellerer, Wolfgang Aalborg Univ Dept Elect Syst DK-9220 Aalborg Denmark Tech Univ Munich Chair Commun Networks D-80333 Munich Germany Nokia Stand D-81541 Munich Germany

In this paper, we study binary tree-algorithms that exploit a combination of multi-packet reception (MPR) and successive interference cancellation (SIC), which so far has not been considered in the literature. Specifically, we assume that the receiver is capable of successfully decoding any collision of up to and including K concurrent packet transmissions and can perform SIC along the tree. We show a number of novel results for this type of tree algorithms. We first derive the basic performance parameters, which are the expected length of the collision resolution interval and the throughput normalized with K, conditioned on the number of contending users. We then analyze their asymptotic behaviour, identifying an oscillatory component that amplifies as K increases. In the next step, we derive the maximum stable throughput (MST) for the gated and windowed access assuming Poisson arrivals. We show that for windowed access, the bound on MST normalized with K increases with K. Finally, we discuss practical issues related to implementation of such scheme, as well as compare it to slotted ALOHA-based schemes that exploit both K-MPR and SIC.

关键词： random-access protocols tree algorithms multi-packet reception (MPR) successive interference cancellation (SIC) massive IoT communications

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Reliability-Based Splitting Algorithms for Time-Constrained Distributed Detection in random-access WSNs

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IEEE TRANSACTIONS ON SIGNAL PROCESSING 2014年第21期62卷 5536-5551页

作者： Laitrakun, Seksan Coyle, Edward J. Georgia Inst Technol Atlanta GA 30309 USA Georgia Inst Technol Sch Elect & Comp Engn Atlanta GA 30332 USA

We consider distributed detection applications for a wireless sensor network (WSN) that has a limited time to collect and process local decisions to produce a global decision. When this time is not sufficient to collect decisions from all nodes in the network, a strategy is needed for collecting those with the highest reliability. This can be accomplished by incorporating a reliability-based splitting algorithm into the random access protocol of the WSN: the collection time is divided into frames and only nodes with a specified range of reliabilities compete for the channel using slotted ALOHA within each frame-nodes with the most reliable decisions attempt transmission in the first frame, nodes with the next most reliable set of decisions attempt in the next frame, etc. The detection error probability (DEP) of the proposed scheme is minimized, and the efficacy is maximized by determining the reliability intervals that define which nodes attempt to transmit in each frame. Intervals that maximize the channel throughput do not always minimize the DEP or maximize the efficacy. Because the scheme orders transmissions of the local decisions in approximately descending order of reliability but suffers collisions, it will offer better performance than a collision-free scheme with no reliability ordering when the time constraint prevents transmission of all local decisions. The transition point between the two schemes is found by deriving the asymptotic relative efficiency (ARE) of the proposed scheme relative to a TDMA-based scheme.

关键词： Binary sensor networks censoring sensors distributed detection ordered transmissions random-access protocols splitting algorithms wireless sensor networks

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MULTIPLE-access IN WIRELESS DIGITAL NETWORKS

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PROCEEDINGS OF THE IEEE 1994年第9期82卷 1360-1370页

作者： ABRAMSON, N DBA Wireless Systems Honolulu HI

General principles for the design of a multiple-access system for large numbers of terminals transmitting to a single hub station are discussed. The importance of understanding the nature of the traffic to be carried by the network is emphasized. After some discussion of multiple access options for steady traffic and for slowly varying traffic, the use of random-access protocols for rapidly varying traffic is explained. Two general random-access protocols have been used in a variety of data networks, ALOHA and CDMA. Although these two techniques have different origins and are generally thought of as separate, they are in fact but different ways of looking at the same basic signals. We show that the use of multiple spreading codes in a CDMA network is not necessary in order to achieve multiple access capability. A single code can greatly reduce the complexity of a CDMA system. We introduce a spread-spectrum version of an ALOHA channel (Spread ALOHA) which is equivalent to a CDMA channel with a common spreading code for all users. The equivalence we demonstrate opens the door to a variety of techniques commonly used in ALOHA channels which can significantly increase both the throughput and the efficiency of the spread-spectrum channel.

关键词： ALOHA CDMA channel capacity code division multiple access complexity data communication systems digital radio systems efficiency encoding hub station multiple access multiple spreading codes multiple-access system packet radio networks protocols random-access protocols spread ALOHA spread spectrum communication spread-spectrum spread-spectrum channel telecommunication channels telecommunication traffic throughput traffic wireless digital networks

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Performance analysis of an optical CDMA random access protocol

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JOURNAL OF LIGHTWAVE TECHNOLOGY 2004年第5期22卷 1233-1241页

作者： Shalaby, HMH Univ Alexandria Dept Elect Engn Fac Engn Alexandria 21544 Egypt

A random-access protocol for an optical direct-detection code-division-multiple-access (CDMA) packet network is proposed. This protocol is called a round-robin receiver/transmitter ((RT)-T-3) protocol. A mathematical description of the protocol is presented using a detailed state diagram. Several performance measures, namely, steady-state system throughput, protocol efficiency, and average packet delay, are derived based on the equilibrium point-analysis technique. The effect of several design parameters on the above performance measures have been examined with the aid of a set of numerical examples. In our numerical calculations chip-level models have been adopted at the receiver side. Our results reveal that an efficiency of more than 90% can be reached easily with mild system parameters. Further an asymptotic efficiency of approximate to 100% is also achievable.

关键词： chip-level receivers code division multiple access (CDMA) direct-detection optical channel on-off keying optical CDMA optical CDMA protocols optical link layer optical networks random-access protocols

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Rao-Test Fusion Rules of Uncensored Decisions Transmitted Over a Collision Channel 21

Rao-Test Fusion Rules of Uncensored Decisions Transmitted Ov...

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21st International Symposium on Wireless Personal Multimedia Communications (WPMC)

作者： Laitrakun, Seksan Mae Fah Luang Univ Sch Informat Technol Chiang Rai Thailand

ISBN: (纸本)9781538657577

We consider composite hypothesis testing problems in distributed detection whose sensors share a collision channel to transmit their uncensored decisions and the fusion center (FC) has a limited time duration to collect local decisions. Rao-test fusion rules for distributed detection whose sensors utilize time division multiple access (TDMA) and frame slotted Aloha to transmit their decisions to the FC are derived. Since using TDMA provides no packet collisions while using frame slotted Aloha induces packet collisions, finding scenarios when one fusion rule achieves a better performance than the other one is our interest.

关键词： Distributed detection Rao test composite hypothesis testing sensor censoring fusion rules random-access protocols

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