DDH-MAC: a novel dynamic de-centralized hybrid MAC protocol for cognitive radio networks

The radio spectrum (3kHz - 300GHz) has become saturated and proven to be insufficient to address the proliferation of new wireless applications. Cognitive Radio Technology which is an opportunistic network and is equipped with fully programmable wireless devices that empowers the network by OODA cycle and then make intelligent decisions by adapting their MAC and physical layer characteristics such as waveform, has appeared to be the only solution for current low spectrum availability and under utilization problem. In this paper a novel Dynamic De-Centralized Hybrid “DDH-MAC” protocol for Cognitive Radio Networks has been presented which lies between Global Common Control Channel (GCCC) and non-GCCC categories of cognitive radio MAC protocols. DDH-MAC is equipped with the best features of GCCC MAC protocols but also overcomes the saturation and security issues in GCCC. To the best of authors' knowledge, DDH-MAC is the first protocol which is hybrid between GCCC and non-GCCC family of protocols. DDH-MAC provides multiple levels of security and partially use GCCC to transmit beacon which sets and announces local control channel for exchange of free channel list (FCL) sensed by the co-operatively communicating cognitive radio nodes, subsequently providing secure transactions among participating nodes over the decided local control channel. This paper describes the framework of the DDH-MAC protocol in addition to its pseudo code for implementation; it is shown that the pre-transmission time for DDH-MAC is on average 20% better while compared to other cognitive radio MAC protocols

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ABSTRACT In this article, we focus on the use of radio frequency wireless LANs, as opposed to infrared wireless systems. For radio frequency wireless LANs, the availability of unlicensed spectrum is a significant enabler. In the United States, it was the Federal Communications Commission's rule change, first published in 1985 (modified in 1990) allowing unlicensed spread spectrum use of the three industrial, scientific, and medical (ISM) frequency bands, that encouraged the development of a number of wireless technologies. Today, unlicensed wireless LAN products are available in all three of the ISM bands at 902-928 MHz,' 2.400-2.4835 GHz, and 5.725-5.850 GHz. As described later, the IEEE 802.11 committee makes use of the 2.4 GHz ISM band. The discussion that follows treats several types of emerging standards which impact wireless LAN systems. We begin with a description of two influential physical-and data-link-layer standards, IEEE 802.11 and HIPERLAN. Following this, we briefly examine some developments concerning the U.S. personal communication services (PCS) bands, future spectrum allocations, and wireless asynchronous transfer mode (ATM) systems. After describing these physical-and link-layer developments, we focus on the network layer. We discuss the extensions being made to the widely used Internet Protocol (IP) t o deal with mobility (wired or wireless). Finally, we describe some emerging standards for wireless link management in which interfaces are specified to provide wireless link information to protocol stacks and applications on the mobile client. In the conclusion, we speculate on future directions of wireless LAN systems. IEEE 802.1 1 WIRELESS LAN STANDARD he IEEE 802.11 committee has been working on the estab-T lishment of a standard for wireless LANs. Having begun its work in 1990, the 802.11 committee is nearing completion of the standard, which is expected to be finalized in mid-1996 Much of the standard appears to have reached final form at the current time (early 1996), so we can describe the main features of the architecture, the multiple physical layers, and the common medium access control (MAC) sublayer [1]. ARCHITECTURE We introduce the general architecture and terminology defined by the 802 11 committee [l]. As shown in 8

Performance Analysis of IEEE 802.15.4 MAC Protocol Under Light Traffic Condition in IoT Environment

In this paper, we propose analytic models for throughput and latency performance of the IEEE 802.15.4 MAC protocol operating under very low duty cycles In the Internet of Things applications. Our analytic models are intended for IEEE 802.15.4 MAC protocol in beacon-enabled star topology with light traffic conditions. Accuracy of the analytic models are verified through extensive simulations using the network simulator ns-2. A strong agreement between simulation results and our theoretical analysis is observed. In addition, we compare throughput and latency performance of two different CSMA/CA protocols in IEEE 802.15.4 and IEEE 802.11. This is motivated by a significant discrepancy of the CSMA/CA mechanism: IEEE 802.15.4 and IEEE 802.11. We observe a remarkable difference in throughput between two protocols. The simulation results also demonstrate an interesting fact that increasing the packet size will degrade the throughput of IEEE 802.15.4 due to the nature of the CSMA/CA mechanism, while a throughput improvement is usually expected

MAC Protocols for WuR Enabled WSNs : Design and Performance Evaluation

Master's thesis Information- and communication technology IKT591 - University of Agder 2017Increasing energy efficiency is a challenging task for protocol design in wireless sensor networks (WSNs) as well as in Internet of things (IoT). Traditionally, duty-cycled (DC) protocols have been widely adopted for data transmissions in WSNs for energy conservation by reducing idle listening and overhearing. Recently, wake-up radio (WuR) has merged as a promising technique to replace DC protocols thanks to its superior performance in both network lifetime and transmission latency. This thesis work focuses on the design and performance evaluation of WuR-enabled MAC protocols considering various traffic conditions and network topologies. As the first step, we investigate the niche of WuR by putting forward a question: Does WuR always consume lower energy than DC protocols? Through in-depth analysis, we ascertain the outstanding energy performance of WuR at light traffic loads. At the same time, we reveal its disadvantages at heavy traffic loads. Secondly, we propose a WuR protocol that is capable of avoiding WuC collisions by enabling a contention-based collision avoidance mechanism for WuC transmissions. The performance of the proposed protocol is evaluated by a Markov chain based mathematical model. Numerical results indicate that our proposed protocol achieves higher packet delivery radio (PDR) and network throughput, with the cost of slightly longer packet delay, compared with an existingWuR protocol. Thirdly, we propose another WuR protocol, referred to as EHA-WuR, which is designed to avoid energy hole in multi-hop networks for multipoint-to-point transmissions. Three operation modes are designed for EHA-WuR. The proposed protocol is implemented in Omnet++ simulator. Numerical results indicate that EHA-WuR significantly extends network lifetime compared with the traditional hop-by-hop operation mode. Key words: Wireless sensor networks, Internet of things, Wake-up radio, Collision avoidance, Energy hole proble

Cyber Physical Systems Oriented Robot Development Platform

AbstractThe development of systems, of various levels of complexity that can integrate physical with virtual components has become a priority for research in the context of emerging paradigms such as Cyber-Physical Systems or Internet for the Future. The authors propose a Robotic Development Platform architecture that integrates principles of Cyber-Physical Systems. The proposed architecture, is scalable, by facilitating the integration of different existing development and simulation tools and will allow robot systems to be tested in different environments, with different characteristics, and facilitate the integration of real world simulation with virtual environment simulation

Adjacency Matrix-Based Transmit Power Allocation Strategies in Wireless Sensor Networks

In this paper, we present an innovative transmit power control scheme, based on optimization theory, for wireless sensor networks (WSNs) which use carrier sense multiple access (CSMA) with collision avoidance (CA) as medium access control (MAC) protocol. In particular, we focus on schemes where several remote nodes send data directly to a common access point (AP). Under the assumption of finite overall network transmit power and low traffic load, we derive the optimal transmit power allocation strategy that minimizes the packet error rate (PER) at the AP. This approach is based on modeling the CSMA/CA MAC protocol through a finite state machine and takes into account the network adjacency matrix, depending on the transmit power distribution and determining the network connectivity. It will be then shown that the transmit power allocation problem reduces to a convex constrained minimization problem. Our results show that, under the assumption of low traffic load, the power allocation strategy, which guarantees minimal delay, requires the maximization of network connectivity, which can be equivalently interpreted as the maximization of the number of non-zero entries of the adjacency matrix. The obtained theoretical results are confirmed by simulations for unslotted Zigbee WSNs

Infrared wireless communication

Infrared wireless communication has already proven to be commercial success in the Television (TV) and Video Cassette Recorder (VCR) remote markets and is poised to become a key technology in a number of business markets. Over the next few years, we may witness an explosive growth of Infrared based walk-up data access and seamless indoor mobile data networking. The protocol architecture proposed by Infrared Data Association (IrDA), a non-profit organization founded in the summer of 1993, is very rapidly emerging as an industry wide infrared standard for walk-up , point-to-point communication The paper examines the IrDA protocol model and how the current printing model can be modified to work over the IrDA proposed protocol stack

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LTE in unlicensed spectrum: indoor planning, performance evaluation, and coexistence with WiFi

The pursuit of more bandwidth and more efficient spectrum usage has led to consider the use of Long Term Evolution (LTE) technology in unlicensed spectrum, a concept particularly useful for indoor deployments. However, LTE must be modified in order to guarantee a fair coexistence with other systems, particularly WiFi. There exist several coexistence methods, such as listen-before-talk (LBT), advanced channel selection, duty cycle, and variations of them. Research into unlicensed spectrum has focused into LTE Licensed Assisted Access (LAA) and LTE-Unlicensed (LTE-U), expected to be specified in 2016. The contribution of this thesis is complementary to the current work, and is focused on coexistence from the perspective of network planning and radio access optimization. This is accomplished with a framework that yields optimized network topologies that maximize the benefits from the LTE deployment, fulfill coverage criteria, and minimize interference. The efficacy of the statistically optimized network topologies has also been validated by means of system level simulations