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Please follow the links to view the publication.Reinforcement learning based ALOHA for multi-hop wireless sensor networks with informed receiving
http://dl-live.theiet.org/content/conferences/10.1049/cp.2012.0582
In this paper, an ALOHA based Medium Access Control (MAC) protocol (RL-ALOHA with Informed Receiving) is proposed for multi-hop Wireless Sensor Networks (WSNs), which overcomes the traditional problems of low throughput, while exploiting their advantages of simplicity, low computational complexity and overheads. Reinforcement Learning (RL) is implemented as an intelligent slot assignment strategy in order to avoid collisions with minimal additional overheads. To improve the energy efficiency, Informed Receiving (IR) and ping packets are applied to avoid idle listening and overhearing. The simulation results show that this approach significantly increases the energy efficiency, achieves over twice throughput of Slotted ALOHA and reduces the end-to-end delay. (6 pages)Internet of Things technology for energy saving of telecom operators
http://dl-live.theiet.org/content/conferences/10.1049/cp.2011.0741
Telecom operators are equipment-intensive enter prise with various types of huge energy consumption equipment, which occupy a large part of the operating costs of production. With the process of social modernization, the state increase emphasis on resource conservation and environment protection. As an emerging technology, Internet of Things technology using for energy conservation of telecom operators can improve the company's own service and operational efficiency. This paper analyzes the energy consumption problems telecom operators equipments faced and give the appropriate IOT solutions which achieves the purpose of equipment energy saving.Adaptive congestion avoidance scheme based on reinforcement learning for wireless sensor network
http://dl-live.theiet.org/content/conferences/10.1049/cp.2011.0664
Energy efficiency and QoS-aware are the key issues of wireless sensor network (WSN). In this paper, we proposed a congestion avoidance scheme devoting to efficient use of energy and adaptive maintain well QoS quality by self-adapt routing. Because it is difficult to obtain the state of network energy and QoS in a practical condition, we are motivated to utilize reinforcement learning to obtain the routing strategy in multi-path communication of WSN. We extend the R-learning algorithm to solve the difficulty of the nodes obtaining the network's status information. We compare the proposed scheme to other congestion avoidance protocols, such as CR. The simulation results show that the performance of our schemes is prior to existing ones.Frequency spectrum access mechanism of cognitive radio based on spectum prediction
http://dl-live.theiet.org/content/conferences/10.1049/cp.2011.0730
In this thesis, a frequency spectrum access mechanism, in which future frequency spectrum state is predicted, is brought forward according to the fact that frequency spectrum detection error of Cognitive Radio is inevitable. That mechanism on support vector machine (SVM) method could evaluate the probability density of idle state duration and occupied state duration of authorized users in given channel. Therefore, it could assess and amend the result of frequency spectrum real-time detection , and could decrease the impact of false alarm probability and misjudgment probability on cognition system and authorized system. The result of simulation shows that the mechanism could obviously decrease the interference of detection error to authorized system, and could apparently reduce the lost of frequency spectrum access chances of cognition system caused by detection error.Study on the influence of IOT (Internet of Things) on mobile network
http://dl-live.theiet.org/content/conferences/10.1049/cp.2011.0742
Mobile communication network provides the terminals of IOT (Internet of Things) with a convenient way to access the network. However a large number of connected IOT terminals will inevitably produce a significant impact on the existing mobile communication network. After summarizing the characteristics of typical applications of IOT, this review provides analysis of the specific impact of IOT on mobile network, and finally proposes the corresponding solutions.Traffic prediction model for cognitive networks
http://dl-live.theiet.org/content/conferences/10.1049/cp.2011.1431
As cognitive networks become so booming, many traditional network utilities must be reconsidered owing to uncertain and complicated changes after spectrum decision. It is a challenge for nodes to predict unknown network traffic precisely combined with spectrum characteristics. In this paper, we present a Relevance Vector Machine (RVM) based traffic prediction model. Based on the judgment of spectrum and wireless environments characteristics, networks traffic can be predicted with periodical samples training to form a close loop feedback. Simulation results for our model are presented and compared to Least Square Support Vector Machine (LS-SVM) scheme, and the simulation results show that the RVM solution improved prediction accuracy up to 60% at most.GUI based cost effective handoff management in WiMAX network entry process using key caching mechanism
http://dl-live.theiet.org/content/conferences/10.1049/cp.2011.0497
Mobility management plays an important role in wireless communication networks in effectively delivering services to users on the move. The trouble is the long delay which occurs during the hand off management in these networks. The key caching mechanism is been introduced in this paper which establishes to prevent the un necessary handoff delay, to minimize the authentication cost along with the 50% consumption in the processing time This mechanism is analyzed in mobile Worldwide Interoperability for Microwave Access (WiMAX) in which IEEE 802.1X authentication procedure is used. This mechanism is investigated analytically and the real time process is been simulated through MATLAB GUI model. The time analysis result indicates that the key caching mechanism can effectively speed up the handoff processes.Media access control protocol modelling for mobile sensor network using OMNeT++ -MiXiM network simulator
http://dl-live.theiet.org/content/conferences/10.1049/cp.2011.0440
Wireless Sensor Network (WSN) consist of large number of battery operated sensing and computing devices deployed randomly for monitoring applications. With the advent of new technologies WSNs are providing a new class of information to human beings. In most cases the networks were stationary but as a evolutionary step the WSNs have to consider mobility. This new class of sensor networks is Mobile Wireless Sensor Networks. Eg moving robots, surveillance aircrafts. Nodes share a single channel for communication. To share communication channel, establishment of a MAC protocol is required in the sensor nodes. The objective of the MAC protocol is to regulate access of the shared wireless medium, so that the performance requirements of the underlying application are satisfied. Energy efficiency and Mobility are big challenges for Medium Access Control protocol design to give a reliable communication. Paper describes a Mobility aware MAC protocol, implemented using OMNeT++ network simulator. OMNeT++ is open source discrete event simulator. Mixim is 'mixed simulator', developed for wireless and mobile simulations in OMNeT++.A high speed turbo decoder implementation for CPU-based SDR system
http://dl-live.theiet.org/content/conferences/10.1049/cp.2011.0622
More and more CPU-based SDR systems appear in recent two years. Such system requires high speed real-time signal processing. In this paper, we present our effort on the speed optimization of Turbo decoder, the most computation-demanding module in all baseband modules. We jointly consider the algorithm parallelism and the processor architecture. Single Instruction Multiple Data (SIMD) instruction is used for software implementation. The evaluation results show that this proposed design can achieve a maximum of 124 Mbps throughput for single Soft Input Soft Output (SISO) module with Max-Log-MAP algorithm.Performance evaluation for high-speed railway mobile communication on HIL simulation platform
http://dl-live.theiet.org/content/conferences/10.1049/cp.2011.0976
An advanced performance evaluation approach, Hardware-in-the-Loop (HIL) simulation for mobile communication system on high-speed railway is introduced in this paper. On the developed HIL simulation platform, channel parameters, such as fading channel model, received level, speed of mobile station, noise and interference can be tuned at ease to simulate various radio propagation environments. HIL simulation platform can achieve real-time simulation in laboratory with high accuracy, low cost and low risk. In addition, the simulation is fully repeatable and fully controllable. The HIL simulation results show that the transmission reliability of mobile communication will deteriorate seriously with the increase of speed and co-channel interference. On the other hand, the transmission reliability will not improve obviously with the increase of received level.A data fusion using un-even clustering for WSN
http://dl-live.theiet.org/content/conferences/10.1049/cp.2011.1460
Data is fused by retransmission node. So combining routing protocol with data fusion at the network layer is one of the important techniques in WSN. The present data fusion protocols usually compress packets without considering the actual integration capabilities. Considering the distribution, the number and the reselecting mode of cluster heads and the integration capabilities of nodes etc., this paper proposed a data fusion algorithm DFHCAC based on heterogeneous clustering and asynchronous reelecting cluster heads to adapt the complexity and changeability of WSN topology. The experimental results show that the survival time of DFHCAC is longer about 47% than LEACH and the energy consumption is less about 25% than LEACH under the same network condition. So DFHCAC's performance is superior to LEACH, it can effective save energy and prolong network life cycle.A load-sharing overlay network design for conferencing VoIP
http://dl-live.theiet.org/content/conferences/10.1049/cp.2010.0529
Voice over Internet Protocol (VoIP) is one of the most important and popular applications for voice communications on the Internet. However, network dynamics of transmission latency and packet loss from public Internet will affect the voice quality of VoIP service. To make sure all participants in large-scale session of conferencing VoIP (CVoIP) have a good perceptual quality, CVoIP needs to pay considerable amount of resource and maintenance cost on client-server architecture of Internet. Therefore, we propose application-layer multicast (ALM) agents to construct a CVoIP multicast overlay network (CVoIPMON) ι with load sharing for cost-effective CVoIP service. Due to the activities of member leaving and joining the CVoIP session, we further apply the product of average link bandwidth and lifetime (i.e. ABTP) as criterion to construct a stable CVoIPMON. In this paper, we use the simulation tool OMNeT++ to obtain experimental results from the simulated CVoIPMON. The performance results demonstrate the load sharing and stability in proposed CVoIPMON for cost-effective CVoIP.On user-participated and service-oriented optical networks
http://dl-live.theiet.org/content/conferences/10.1049/cp.2010.1171
ICT (Information and Communication Technologies) networks are moving to support data, voice, video converged triple play, service-oriented intelligence of resource sharing, reconfiguration, and user-participated DIY (Do It Yourself) on virtual private network control and management. To accommodate these amazing features, future optical network should provide intelligent control and management for reliable transmission, which may employ user-participated and dedicated end-to-end lightpath such as the UCLP of CANARIE CANET4, also highly dynamic operation facilities for distributed multi-domain interconnecting. This paper forces on challenges and potential enabling technologies for user-participated and service-oriented optical networks. The topics involved include network virtualization, service model, architecture, and implementation, user-participated network interface.An adaptive secure RFID scheme supporting multiple databases
http://dl-live.theiet.org/content/conferences/10.1049/cp.2010.0749
In recent years, the research on Radio Frequency Identification (RFID) system has presented certain solutions that can meet the corresponding security requirements to some extents. However, the issues with multiple databases in RFID system, which are common in the real world, have gained little attention in the existing schemes. Although ONS (Object Name Service) solution is aimed at supporting multi-database in RFID system, it still has great security risk because of the lack of protection of the tag ID. In this paper, a new solution is presented which can provide sound protection of the tag ID and is adaptable to multiple databases, which can meet the security requirements of RFID system.An autonomic communication based conceptual and architecture model for cognitive radio nodes
http://dl-live.theiet.org/content/conferences/10.1049/cp.2010.0651
Cognitive radio has been a research hotspot because of its promise to improve the utilization of the assigned but unused radio spectrum. To accomplish this task, cognitive radio network should configure itself to adapt to its communication context. Autonomic computing and communication have been proposed to enable the computing and communication network self-management. Based on the similarity between cognitive radio and autonomic communication, the cognitive cycle is modeled by autonomic computing principles. Then, cognitive radio conceptual and architecture model with autonomic property are proposed. Cognitive radio nodes realized by the proposed models are easy to form an autonomic cognitive radio network, which can be looked as an autonomic communication environment. The autonomic cognitive radio node is expressed by autonomic communication element (ACE) architecture and a realization method is given based on the open-source ACE toolkit, which establishes a simulation environment for cognitive radio research.Research of WSNS coverage in coal mine based on GNG-like intelligent algorithm
http://dl-live.theiet.org/content/conferences/10.1049/cp.2010.1029
Coverage in wireless sensor networks (WSNs) is treated as a key technology for many monitoring applications. A novel sensor node's model is presented based on the neural network because the exiting models are not feasible in the special coal mine environment. In addition, we provide an improved intelligent algorithm GNG-Like(Growing Neural Gas-Like), taking into consideration application-special requirements and energy-conservation characteristics, which is applied into the coal mine to study the dynamic coverage in the inspection field. In GNG-Like, threshold is set and corresponding parameters are modified to achieve fast response and coverage for the changing environment in coal mine. We simulate GNG-Like algorithm in the Java platform and compare it to GNG intelligent algorithm. Simulation results show that, compared with the exiting GNG, GNG Like has a faster reaction rate, achieves optimize dynamic coverage and prolongs the network lifetime.Real-time estimation of excess atmospheric attenuation using an artificial neural network with a two-frequency input
http://dl-live.theiet.org/content/conferences/10.1049/cp.2009.1194
A simple artificial neural network is considered for real-time estimation of excess atmospheric attenuation on a satellite communication link with known attenuation at two frequencies. All atmospheric contributors to attenuation are considered except for gases. The network has a two-layer feed-forward structure with 32 neurons in the hidden layer. Its performance is evaluated by computer simulation using 447 hours of measured attenuation data at 20, 40, and 50 GHz. Estimated attenuation tracks well the measured attenuation at 50 GHz. Estimation error standard deviation is 0.36 dB. RMS error is a function of attenuation: it increases slowly with attenuation, but the ratio of error to attenuation decreases with increasing attenuation. This approach accurately estimates excess attenuation without requiring assumptions, but required training data. (4 pages)A Quasi-map estimation algorithm for multiple frequency offsets in distributed MIMO system
http://dl-live.theiet.org/content/conferences/10.1049/cp.2009.2051
This paper addresses a novel quasi maximum a posterior (MAP) estimation algorithm for multiple frequency offsets in distributed multiple inputs and multiple outputs (MIMO) system in the presence of prior information about frequency offsets. In this paper, the prior information is considered and the Cramer-Rao Bound (CRB) for the problem at hand is derived. Additionally, taking advantage of prior information, the algorithm of maximum a posterior is investigated. First, the variance of prior information can be estimated according to the range of the frequency offsets. Then a quasi MAP estimation algorithm will be introduced. Compared with the maximum-likelihood estimation, simulation results illustrate the performance of quasi MAP estimator achieves the CRB and the proposed algorithm can improve the efficiency of synchronization obviously, especially in low Signal to Noise Ratio (SNR) environment. Furthermore, its complexity is less than MAP estimation.Blind estimation of source number based on SVM in wireless communication systems
http://dl-live.theiet.org/content/conferences/10.1049/cp.2009.1902
In this paper, a novel method to estimate the number of source signals based on support vector machine (SVM) is proposed. The estimation problem of number of source signals is transformed into the problem of multi-class classification, and the SVM is applied to solve the problem of multi-class classification. The proposed method can be used when the modulation type chooses from the QPSK and BPSK at random. The application of the novel method can expand present well-determined situation and over-determined situation into the under-determined situation. Simulation results confirmed these conclusions.Software defined radios, cognitive radio and the software communications architecture (SCA) in relation to COMMS, radar and ESM
http://dl-live.theiet.org/content/conferences/10.1049/ic_20080393
In this paper we describe the role of software defined radio and in particular the software communications architecture (SCA) in relation to communications, radar and electronic support measures (ESM). We discuss the evolving timeline of software defined radio standards and programmes, and look at the various implementation approaches. The paper covers development of an example ESM application highlighting the complexity of the signal processing requirement and noting how this can be captured with components and interconnect elements within a model driven architecture based development tool. The paper considers the impacts of cognitive radio techniques and concludes with consideration of some of the potential benefits of software programmable radio techniques. (7 pages)Research on the telecommunication information centre technical solution
http://dl-live.theiet.org/content/conferences/10.1049/ic_20080276
The thesis is mainly concerns technical solution of the telecommunication information centre. It also points out the detailed system architecture utilizing Voice XML technology and the information search engine technology. The framework has made the telecommunication information centre project feasible.The relevance of the CLP measure of a VoIP system with regard to QoV
http://dl-live.theiet.org/content/conferences/10.1049/cp_20080637
Communication systems are undergoing constant and rapid innovation, both at the design stage and in the field. This in turn has led to an increasing need for fast, efficient, portable and economic methods for the testing of these systems. For voice carrying communication systems the quality of the transmitted voice that the system produces is a large factor in the systems overall performance rating. This measure is known as the 'Quality of Voice' (QoV) and can be evaluated either subjectively or objectively. Speech quality is a complex subjective phenomenon that can be best quantified by subjective testing. A subjective QoV measurement requires a 'listener' to rate a sample of speech produced by the system under test. To achieve accurate results an average rating, or Mean Opinion Score (MOS), must be found from a large panel of listeners. This results in subjective QoV testing being a highly expensive and time consuming process to conduct. This has driven the requirement for automated objective QoV testing systems which can operate efficiently and cost-effectively. The method described here aims to increase the efficiency of a previously established Non-intrusive objective QoV estimation system designed for use with a VoIP based network. The existing system takes as its inputs four operational parameters (Conditional and Unconditional Packet Loss Probabilities, Codec Type and Speaker Gender) of the communication system under test. These parameters are then mapped to a QoV score. This paper will identify the Conditional Loss Probability (CLP) parameter as being of least significance with regard to the QoV score achieved by the VoIP network. A similar QoV estimation system will then be developed with the CLP measure eliminated. This system will be tested to demonstrate that a system taking only three operational parameters of a VoIP system can still maintain a high degree of accuracy.A wireless Internet interface for person with physical disability
http://dl-live.theiet.org/content/conferences/10.1049/cp_20081098
Technologically assistive devices are increasingly playing more important roles in the lives of persons with disabilities, with one of the more promising considerations being a combination of the functions of computer software and hardware. However, using a conventional keyboard for Internet access is prohibitive for persons whose hand coordination and dexterity are impaired by ailments such as amyotrophic lateral sclerosis, multiple sclerosis, muscular dystrophy, and other severe handicaps. To assist participants with physical disabilities in sharing the resources of the Internet, we designed and implemented an easy-to-operate wireless input interface using Morse code as the adaptive communication tool. Moreover, a adaptive Morse code recognition process is introduced. After two months' practice on this system, three participants with physical disabilities could conveniently gain access to the Internet. (7 pages)Experimental evaluation of a single access point bluetooth localisation system
http://dl-live.theiet.org/content/conferences/10.1049/cp_20080672
Location tracking is a wide field of research with many different solutions. One common trait of many of these solutions is the necessity for a large amount of hardware infrastructure. This work attempts to address this deficiency of typical solutions by developing a localisation system which requires only one piece of infrastructure to be installed, the basestation computer. The proposed localisation system uses classifiers to translate the radio signals coming from a Bluetooth enabled mobile phone to predictions of the currently inhabited room. This paper investigates the applicability of Linear Discriminant Analysis and Support Vector Machines to such a system. Furthermore, experimental results for an in-home environment are used to evaluate the accuracy and repeatability of the proposed localisation system.An efficient joint algorithm based on one training sequence for OFDM system
http://dl-live.theiet.org/content/conferences/10.1049/cp_20080772
Based on the key technology of wireless communication systems-Orthogonal Frequency Division Multiplexing (OFDM), an efficient joint algorithm is proposed. We exploit a training sequence to estimate the integer frequency offset and channel parameters, and lower the peak-to-average power ratio by using the data of the training sequence as the coefficients of partial transmit sequence (PTS) algorithm. Results of simulations indicate that this method can simultaneously realize frequency synchronization, channel estimation and the low peak-to-average power ratio by using one training sequence. The OFDM system with the proposed algorithm has better BER performance and can be implemented with improved validity and reduced redundancy information.A new network fault location method based on (CBR/MBR)
http://dl-live.theiet.org/content/conferences/10.1049/cp_20080839
At present.it is general to apply a single AI (artificial intelligence) technology to fault diagnosis, the actual state cannot meet the whole demands of the exact fault identification and diagnosis. With regard to it , a integrate fault location method is given after the study of the question about the network fault location. It can reduce the amount of information presented to network operator by filtering out unnecessary or irrelevant events.Simultaneously, the semantic content of the information presented can be increased by the correlation process, hence helping to establish the underlying problem or condition which produced the events.This fault location method is divided into two phases: the initial alarm correlation and the potential alarm correlation. The typical alarm correlation methods are used to conduct a preliminary filtering in the initial alarm correlation.The integrate application of CBR (case based reasoning) and MBR (model based reasoning) further the network fault location in the potential alarm correlation. The network fault location method can settle the bottleneck to a certain extent and show good performance in fault location after the simulation test of the network fault location .A new bandwidth prediction based wireless ad-hoc video communication
http://dl-live.theiet.org/content/conferences/10.1049/cp_20070328
In this paper, we propose a new bandwidth prediction and control scheme for transmission of real-time video stream over wireless ad hoc network. Our proposed strategy is based on cross-layer, feedback and neural network techniques. We first determine several relevant parameters which directly impact the quality of video transmission. We obtain the topology change, the signal power information by using cross-layer mechanism. We obtain the packet loss statistics and the network jitter from receiver feedback. Subsequently, we extract their relevant features from those sample data, and take them as the input for training data of the neural network. The predicted result of the neural network would be used as the bandwidth of mobile ad-hoc network (MANET). This parameter will be used to control video encoder to adjust the bit rates of real-time video stream. We have implemented an integrated video streaming system simulation for proving our proposed scheme. In contrast to the conventional transfer scheme, the results of our proposed control strategies indicate that there are considerable improvements in the packet loss and the real time visual quality.The application of wireless sensor networks with multi-agent systems
http://dl-live.theiet.org/content/conferences/10.1049/cp_20070117
Wireless sensor networks have been identified as one of the most important technologies for the 21 st century, which have already enabled numerous embedded wireless applications. In this paper, we introduce a design system of the wireless sensor networks with multi-agent systems for lighting control of intelligent building. The system of intelligent buildings control provides a practical application that can benefit directly from artificial intelligence techniques with wireless sensor networks. Such design of an MAS for WSNs-based system requires issues in several interrelated areas including systems design, decision making, machine learning, topology management, message routing, and HCI (human-computer interaction).A neural network blind equalization algorithm based on variable momentum factor
http://dl-live.theiet.org/content/conferences/10.1049/cp_20070125
The influence of momentum term to blind equalization algorithm was analyzed in this paper. A new neural network blind equalization algorithm based on variable momentum factor was proposed, which adopted the non-linear function of mean square error as the variable momentum factor. The simulation shows that the new algorithm has faster convergence rate, smaller state residual error and lower bit error rate.Location-based access discovery based on pattern classification in B3G mobile systems
http://dl-live.theiet.org/content/conferences/10.1049/cp_20070262
With various radio access networks being deployed over the world, B3G mobile system is conceived to integrate all these radio access networks in order to provide ubiquitous multiservice network to end users. The discovery of available Radio Access Networks is essential in B3G mobile systems. In this study, a location-based access discovery mechanism based on pattern classification is proposed. It is argued that location-based access discovery problem can be handled by an origin-derivate pattern classification method. Accordingly, a system based on multiple probability neural networks is proposed. The experiment results show that the system can effectively discover available Radio access in B3G mobile systems.Study of localization scheme base on neural network for wireless sensor networks
http://dl-live.theiet.org/content/conferences/10.1049/cp_20070084
Precise knowledge of node location in wireless sensor network yields a wide variety of profound advantages. In this paper, localization scheme base on neural network for wireless sensor networks is described. We adopt neural network to model sensor network. The trained neural network can integrate global information of the sensor network as anchor nodes character, nodes deposited, environment, etc. The results of simulation demonstrate that the location scheme can obtain higher accuracy of location estimation, requires less anchor nodes and do not affected by NLOS environment and irregularity of anchor nodes radio power.A multiple constrained QoS routing algorithm based on Hopfield neural network
http://dl-live.theiet.org/content/conferences/10.1049/cp_20070252
This paper presents a multiple constrained QoS routing algorithm based on Hopfield NN. Multiple constrains conclude delay, bandwidth, delay-jitter, cost and so on. The expressions of network cost and path are given which is related with QoS and this problem can be regarded as a shortest path. Representing the shortest path problem as a Hopfield NN and establishing a NN model. Finally, an energy function is constructed which takes into account all objectives and constraints.Blind multi-user detection based on lagrange optimization neural network
http://dl-live.theiet.org/content/conferences/10.1049/cp_20070105
A kind of Lagrange principle of optimizing neural network is sketched in the paper, it has overcome the traditional defect based on that the neural network which punish function thought exists deal with inequality restraint directly reduce network size and complexity a kind of new optimization neural network Based on the Lagrange neural network, proposed a kind of blind multi-user detection algorithm, and indicated through the computer simulation, this algorithm has the improvement in the error rate performance aspect, the convergence rate also obviously enhances.An efficient document-split algorithm for on-demand XML data broadcast scheduling
http://dl-live.theiet.org/content/conferences/10.1049/cp_20070260
XML data broadcast is attracting more and more interests from many researchers. In on-demand XML data broadcast, the existing broadcast scheduling methods usually only considered the document-selectivity of user requests. In this paper, we propose an efficient document-split algorithm which considers the branch-selectivity for on-demand XML data broadcast scheduling. First, we divide the user requests into two sets according to the branch-selectivity; then split every document into two parts according to these two sets. With our scheduling algorithm, the hot and small branches are broadcast first. User requests with low branch-selectivity can be satisfied in a shorter time and both of access time and tuning time are reduced. Experiments show that our algorithm provides significantly better performance when compared with existing scheduling algorithms.Development of smart mobile phone based on software radio and PR-QMF communication model
http://dl-live.theiet.org/content/conferences/10.1049/cp_20070118
This paper researches a new unifying model of multi-user communication system based on perfect-reconstruction quadrature mirror filters (PR-QMF). software radio (SR) technology is applied in this paper in order to develop the smart mobile phone. The hardware evaluation board of smart mobile phone is constructed by S3C2410 processor and M23 base band/radio frequency (RF) processor, while its software platform is designed by embedded Linux and Qt/embedded. The smart phone supports speech service, short message service (SMS), image service, and network service, etc. The features and difficulties in the research and development (R&D) of smart phone's hardware and software are presented in detail in this paper. In the end, the TDMA multiple access is implemented on this unifying model of multi-user communication by means of the smart mobile phone evaluation board, which provides a perfect example for the further research.Open WSN, an layer first component architecture and package for sensor networks
http://dl-live.theiet.org/content/conferences/10.1049/cp_20070331
Most of the current WSN research platforms are based on Mica nodes and TinyOS. However, it's difficult to be integrated with the obsolete mature source code and difficult to port to other platforms. The micro-controller based solution is also weak to take high performance tasks such as image processing. So we develope an ARM7 based powerful WSN research platform named OpenWSN. OpenWSN adopts layer- first component based architecture. The hierachical feature makes it much easier to port to other hardware platforms. And OpenWSN introduces object oriented design and C language for implementation, which can make full use of the current mature source codes and human resources to lower the cost of future developing. Some more techniques are also introduced such as static resource allocation and service based policy to increase its robustness for real application. In general, OpenWSN is an appropriate solution for both industry and academia.The performance analysis of support vector machine parameters based on statistical analysis
http://dl-live.theiet.org/content/conferences/10.1049/cp_20070165
By using support vector machine learning method for audio classification, we compare the classification accuracy of different parameter combinations and analyze parameters impact on classification accuracy, number of support vectors and classification time. According to the statistical analysis, we find that the value of σ<sup xmlns="http://pub2web.metastore.ingenta.com/ns/">2</sup> has more influence on classification accuracy, number of support vectors and classification time than that of C. Based on the analysis, we propose a new parameter selection method about how to improve classification accuracy and reduce classification time.Sub-band-patch-through heuristic for cost efficient wavelength assignment in DWDM networks
http://dl-live.theiet.org/content/conferences/10.1049/ic_20070503
This paper discusses a heuristic for cost efficient wavelength assignment by saving mux/demux cards at nodes in an all-optical network while using the possibility to patch through wavelengths of a sub-band at intermediate nodes. (2 pages)How to implement a system based on an evolving broadband standard
http://dl-live.theiet.org/content/conferences/10.1049/ic_20060477
The lecture is going to describe a subsystem concept for the infrastructure portion of a wireless mobile broadband digital transceiver system. The system platform is software based, flexible and capable of processing multiple air interface standards. Choosing the right algorithm partitioning options and data flow considerations, it has been ensured that the platform is ready for the next iteration of the living standard. The same platform is still able to cope with the legacy versions. The complementing development flow ensures appropriately low cycle time for necessary design iterations.Implementation and comparison of a wideband HF noise and interference simulator
http://dl-live.theiet.org/content/conferences/10.1049/cp_20060254
The present needs for more accurate modelling and simulation of the wideband HF channel motivate the development and implementation of wideband channel simulators. It has been showed that many HF communication systems may properly mitigate the ISI distortion of the HF channel, but it may perform badly under the HF noise and interference. In this paper, a software simulation of a wideband noise and interference system (NI) is described. The validity of the HF simulator is demonstrated by the analysis of the results of the simulator and comparisons with measured noise/interference. The comparisons of the model with measurements will be made with a variety of first and higher order statistics.A software-defined HF sensor for geo-locating noise and interference
http://dl-live.theiet.org/content/conferences/10.1049/cp_20060253
The Signal to Noise Enhancement Program (SNEP) has built a software-defined, combined noise monitoring and geo-positioning system. RF-control includes a LABVIEW and MATLAB software controlled sensor, using generalized RF down-conversion and sampling. Based upon observed noise and interference levels, the sensor system directs synchronized sampling at three or more remote sensors. The system computes time correlation between the received noise energy, and it computes a hyperbolic time-difference-of-arrival geo-positioning solution for the noise source. RF-control allows for remote control and reporting results via network connection.Simulation of energy efficient data dissemination in wireless sensor networks
http://dl-live.theiet.org/content/conferences/10.1049/cp_20060654
In this paper we present the simulation-based performance evaluation and tuning of data dissemination in wireless sensor networks. The simulation uses directed diffusion protocol for query and data dissemination. The implementation is done in Java using eclipse. The simulation includes four phases: interest propagation, gradient establishment, data propagation, and reinforcement of path establishment and truncation. The objectives of protocol tuning include: a) reduced energy consumption, and b) the selection of the best path to send the data back from the event source to the sink. The simulation design is scalable and reusable; the same set of classes can be extended for the simulation of other protocols. (4 pages)Tele-contiguity and interaction: architecture as communication interface
http://dl-live.theiet.org/content/conferences/10.1049/cp_20060690
This paper is centered on the use of video-communication and tele-collaborative applications in temporary architecture. Today we live in an electronic society in which computers, mobile phones, Internet have become integral part of our everyday lives. Architecture has to interject the new space characteristics: fluxes and interrelations should become the goal of research. This approach has three significant characteristics: unification of real and virtual worlds both input and output, tele-contiguity between remote participants, convergence of amplified perceptions and sensible spaces. Tele-contiguity is superintended as an improvement of body materiality through sensory amplification and not as an impoverishment of human sensory system: the system should support an environment that looks like a natural and functional extension of the space that people use in their everyday activities. (5 pages)Blind equalization algorithm based on forward neural network in QAM system
http://dl-live.theiet.org/content/conferences/10.1049/cp_20061346
In this paper, an improved blind equalization algorithm based on multiple-layer forward neural network is proposed, and a new transfer function for the neural network is designed. The computer simulations show that the improved algorithm have faster convergence speed and smaller bit error rate than traditional forward neural network algorithm. (4 pages)Platform for joint evaluation of FPGA-implemented and Matlab algorithms in real MIMO transmissions
http://dl-live.theiet.org/content/conferences/10.1049/ic_20050373
This contribution describes a MIMO simulation and validation platform suitable for a progressive implementation of real-time signal processing algorithms. We describe a platform that allows sharing Matlab, simulated VHDL and hardware designs while transmitting through a real MIMO channel. The applicability and first results of this platform are shown for a narrowband 2×2 spatial multiplexing system operating in the 2.4 GHz band. (4 pages)Fundamental saturated amplifier channel power dynamics in transparent networks
http://dl-live.theiet.org/content/conferences/10.1049/cp_20050675
The optical power response of wavelength-division-multiplexed channels to gain variations in uncontrolled saturated amplifiers in high-capacity, large node-count transparent mesh networks is studied through numerical simulations. (2 pages)Simulation of wireless sensor networks localization with OMNeT++
http://dl-live.theiet.org/content/conferences/10.1049/cp_20051468
Wireless sensor networks are being developed for use in monitoring a host of environmental characteristics across the area of deployment, such as light, temperature, sound, and many others. Localization plays an important role in wireless sensor network applications when the positions of nodes cannot be decided beforehand or, if nodes are mobile. A distributed, scalable algorithm for estimating the localization of nodes in a wireless sensor network is described in detail. Simulations were performed with the software of OMNeT++. The results show that in the presence of 5% measurement range errors, 20 percentages beacon node population, and average neighbors of 12 nodes, the estimation errors of the algorithm proposed are about 25% on average. It is also shown that, the algorithm performs well with up to 35% measurement range errors. (6 pages)Energy optimization for mobile MPEG-4 video decoder
http://dl-live.theiet.org/content/conferences/10.1049/cp_20051484
Most compiler optimization techniques concern most about speed. In this paper, we present two high-level power/energy optimization methods for ARM-based battery-powered embedded multimedia systems, e.g. mobile phones, pocket PCs, personal multimedia systems, etc. The experiments using MPEG-4 simple profile level 0 (SP@L0) video decoder on ARM920T with two QCIF video sequences 15 fps, 24 kbps show that the proposed techniques can complement the existing speed-oriented ones to achieve lower energy/power consumption up to 13% relative to all ARM C++ optimization levels despite the 16-KB instruction and 16-KB data caches of ARM 920T core. (6 pages)SIMULINK simulation of a stationary indoor MIMO wireless system
http://dl-live.theiet.org/content/conferences/10.1049/cp_20050310
A SIMULINK simulation of a multiple-input/multiple-output (MIMO) Communications system model is described with reference to actual radio channel measurements from a microwave network analyser. Results are presented which indicate the effect of a changing surrounding environment with respect to a stationary MIMO communications system. The approach taken is to assume that changes in the surrounding physical environment give rise to measurement errors with respect to the quantities that were originally measured.Anycast routing in optical burst switched grid networks
http://dl-live.theiet.org/content/conferences/10.1049/cp_20050678
To deliver virtually unlimited computing power to residential users, an anycast routed optical burst switched grid infrastructure is proposed. This architecture is evaluated and compared with traditional shortest path routed systems in optical circuit switched and burst switched networks. (2 pages)