A Simulation Platform for Evaluating RFID and WSN’s Energy Efficiencies

Advances in the wireless, RFID and sensor technologies has given rise to a plethora of diverse WSN motes that can be used in association with numerous applications. Experimenting with new MAC algorithms and various functionalities on a real sensor network to obtain energy efficiency is both time consuming and expensive especially when these different mote platforms are deployed in one application. Generally Simulators are used to approximate the performance of MAC protocols. Out of the numerous simulators available, none can simulate the energy efficiencies given different types of motes and environments in one application. Hence, the need of a simulation platform for a mix deployment of different types of WSNs and RFIDs is felt to access application performance requirements while curtailing energy consumption to enhance application lifetime. In this paper, we presents an extension of our effort EnergySim [1], which is a simulation platform developed dedicatedly for evaluating energy efficiencies. In this paper we have discussed the simulation modes, methodology and architecture of our proposed simulator with some future extensions presented at the end of the paper

Energy Efficient Cooperation in Underlay RFID Cognitive Networks for a Water Smart Home

Shrinking water  resources all over the world and increasing  costs of water consumption  have prompted  water users  and distribution companies  to come up with water conserving strategies. We have proposed an energy-efficient  smart water monitoring application in [1], using low power RFIDs. In the home environment,  there exist many primary interferences within a room, such as cell-phones,  Bluetooth  devices, TV signals, cordless phones and WiFi devices.  In order to reduce the interference  from our proposed RFID network for these primary  devices, we have proposed a cooperating  underlay  RFID cognitive network for our smart application on water.  These underlay  RFIDs should strictly adhere to the interference thresholds to work in parallel with the primary wireless devices [2].  This work is an extension of our previous  ventures proposed in [2,3], and we enhanced the previous efforts by introducing  a new system model and RFIDs.  Our proposed scheme is mutually energy efficient and maximizes the signal-to-noise ratio (SNR) for the RFID link, while keeping the interference levels for the primary  network below a certain threshold. A closed form expression for the probability density function (pdf) of the SNR at the destination reader/writer and outage probability are derived. Analytical results are verified through simulations. It is also shown that in comparison to non-cognitive selective cooperation,  this scheme performs  better in the low SNR region for cognitive networks. Moreover, the hidden Markov model’s (HMM) multi-level variant hierarchical hidden Markov model (HHMM) approach is used for pattern recognition and event detection for the data received for this system [4]. Using this model, a feedback and decision algorithm is also developed.  This approach has been applied  to simulated water pressure data from RFID motes, which were embedded in metallic water pipes

Vision-based Semantic Communications for Metaverse Services: A Contest Theoretic Approach

The popularity of Metaverse as an entertainment, social, and work platform has led to a great need for seamless avatar integration in the virtual world. In Metaverse, avatars must be updated and rendered to reflect users' behaviour. Achieving real-time synchronization between the virtual bilocation and the user is complex, placing high demands on the Metaverse Service Provider (MSP)'s rendering resource allocation scheme. To tackle this issue, we propose a semantic communication framework that leverages contest theory to model the interactions between users and MSPs and determine optimal resource allocation for each user. To reduce the consumption of network resources in wireless transmission, we use the semantic communication technique to reduce the amount of data to be transmitted. Under our simulation settings, the encoded semantic data only contains 51 bytes of skeleton coordinates instead of the image size of 8.243 megabytes. Moreover, we implement Deep Q-Network to optimize reward settings for maximum performance and efficient resource allocation. With the optimal reward setting, users are incentivized to select their respective suitable uploading frequency, reducing down-sampling loss due to rendering resource constraints by 66.076\% compared with the traditional average distribution method. The framework provides a novel solution to resource allocation for avatar association in VR environments, ensuring a smooth and immersive experience for all users.Comment: 6 pages,7figure

Performance Analysis of Free-Space Information Sharing in Full-Duplex Semantic Communications

In next-generation Internet services, such as Metaverse, the mixed reality (MR) technique plays a vital role. Yet the limited computing capacity of the user-side MR headset-mounted device (HMD) prevents its further application, especially in scenarios that require a lot of computation. One way out of this dilemma is to design an efficient information sharing scheme among users to replace the heavy and repetitive computation. In this paper, we propose a free-space information sharing mechanism based on full-duplex device-to-device (D2D) semantic communications. Specifically, the view images of MR users in the same real-world scenario may be analogous. Therefore, when one user (i.e., a device) completes some computation tasks, the user can send his own calculation results and the semantic features extracted from the user's own view image to nearby users (i.e., other devices). On this basis, other users can use the received semantic features to obtain the spatial matching of the computational results under their own view images without repeating the computation. Using generalized small-scale fading models, we analyze the key performance indicators of full-duplex D2D communications, including channel capacity and bit error probability, which directly affect the transmission of semantic information. Finally, the numerical analysis experiment proves the effectiveness of our proposed methods

Development of a cost-effective high performance pattern analyzer using transputer system

108 p.The research project "Developing a cost-effective high performance pattern analyser transputer system" was completed on May 1997. The objective of this project was to develop a pattern recognition system for computer vision using transputers placed in an IBM PC (Personal Computer). Four final year projects were involved in the development of the project, dealing withvarious aspects of pattern recognition.RP 18%#47;9

Research and development in quality of service multicast routing in MANET

This report summarizes the main research work during the past three and a half years of the project undertaken at Positioning & Wireless Technology Centre (PWTC) of NTU. It covers the following research topics: centralized multi-constrained Quality of Service (QoS) routing algorithms, MANET test-bed developments, QoS routing protocol for multi-cluster based ad hoc network with mobile backbone, QoS multicast routing protocol for multi-cluster based mobile ad hoc network (MANET), and hierarchical routing algorithms for large scale road networks. For the centralized multi-constrained QoS routing problem, by keeping limited number of non-dominated paths in each node according to a nonlinear path function, we have proposed Limited Path Dijkstra’s Algorithm (LPDA) and the Improved Limited Path Heuristic Algorithm (ILPHA). It is shown that our ILPHA improves the previous Limited Path Heuristic Algorithm (LPHA) significantly, and the heuristic algorithms with dominating area non-linear path function outperform the heuristic algorithms with the max weight based non-linear path function. For MANET test-bed developments, our practices in two MANET test-beds for video conference and video surveillance will be given, their implementation architecture and their notable features will be introduced. MANET addresses challenging QoS routing problem, particularly when the network is in large scale. We have studied the ad hoc network with Mobile Backbones (MBN) and this report introduces our findings for design of a hybrid QoS routing protocol for MBN. It is based on a proactive Intra-group Link state Updating Protocol (ILUP) and reactively discovery multiple segmented QoS paths sequentially from the source to the destination. The route search algorithm is modified from the k-shortest path algorithm or the Limited Path Dijkstra’s Algorithm (LPDA). Simulation results show the efficiency of the proposed protocol

A new energy-efficient local metric for Channel-Aware Geographic-Informed Forwarding (CAGIF) in wireless sensor networks

This paper proposes a new energy-efficient local metric, termed as efficient advancement metric (EAM), for channel aware geographic-informed forwarding (CAGIF) algorithm, which studies the optimal selection of the relay nodes by taking into account the underlying channel conditions. The proposed metric considers not only the forward distance but also the packet successful probability under a certain channel condition, rather than purely maximizing the forward distance, to choose the most energy-efficient relay node in the geographic- informed routing protocol in a CDMA-based wireless sensor network. The proposed algorithm only requires that nodes have the knowledge of their own location information and the location information of the source and destination nodes. The protocol assumes that nodes could vary transmission range to search for the optimal relay nodes according to this metric. An analytical framework is provided and numerical results show that there exists an optimum distance of a relay node under a certain channel condition to maximize the EAM for any fading conditions.Accepted versio

The Effect of Unreliable Wireless Channel on the Call Performance in Mobile Network

In this paper, we propose a model to study the call performance in mobile network taking into account the inherent time varying wireless channel. The performance metrics call complete probability and call complete ratio are introduced and further derived with the general call holding time. The impacts of the wireless channel error characteristics and the system parameters on the call performance are illustrated and discussed. The sensitivity problem with respect to the call holding time distribution is investigated. The result indicates that both call complete probability and call complete ratio exhibit a significantly different variation under different call holding time. The analytical model is verified by simulation result

Energy efficiency analysis of channel aware geographic-informed forwarding (CAGIF) for wireless sensor networks

This letter analytically examines the achievable energy efficiency of channel aware geographic-informed forwarding (CAGIF) algorithm, which chooses the next hop relay node by taking into consideration the underlying channel conditions, rather than purely maximizing the forwarding progress. The theoretical analysis in terms of the average forward distance is developed and the upper bound and lower bound of the average energy consumption are provided by referring to the retransmission techniques. Numerical results show that CAGIF significantly improves the energy efficiency over the previous geographic information based routing algorithms that ignore the channel conditions.Accepted versio