Article

Performance Study of Localization Techniques in Wireless Body Area Sensor Networks

Authors:
To read the full-text of this research, you can request a copy directly from the authors.

Abstract

One of the major issues in Wireless Body Area Sensor Networks (WBASNs) is efficient localization. There are various techniques for indoor and outdoor environments to locate a person. This study evaluating and compares performance of optimization schemes in indoor environments for optimal placement of wireless sensors, where patients can perform their daily activities. In indoor environments, the performance comparison between Distance Vector-Hop algorithm, Ring Overlapping Based on Comparison Received Signal Strength Indicator (ROCRSSI), Particle filtering and Kalman filtering based location tracking techniques, in terms of localization accuracy is estimated. Results show that particle filtering outperforms all. GPS and several techniques based on GSMlocation tracking schemes are proposed for outdoor environments. Hidden Markov GSM based location tracking scheme efficiently performs among all, in terms of location accuracy and computational overheads.

No full-text available

Request Full-text Paper PDF

To read the full-text of this research,
you can request a copy directly from the authors.

... Unlike proactive routing protocols, where all the routes are formulated whenever the network initializes (e.g. [39], [40], [41]), in reactive approach, routes are queried only when needed by a node. A route request is flooded in the entire network and when a route is established, data is to be sent. ...
... His work is applicable for both MANETs and VANETs. N. Javaid et al.[39] ensured energy and delay of reactive routing for wireless multi-hop network.Authors of ([39],[14]) give detailed analysis on performance metrics of MANETs and VANETs routing Protocols.Kumar. S et al. [43] addresses path stability and link duration in reactive as well as proactive routing protocols for MANETs. ...
... His work is applicable for both MANETs and VANETs. N. Javaid et al.[39] ensured energy and delay of reactive routing for wireless multi-hop network.Authors of ([39],[14]) give detailed analysis on performance metrics of MANETs and VANETs routing Protocols.Kumar. S et al. [43] addresses path stability and link duration in reactive as well as proactive routing protocols for MANETs. ...
Article
Reactive routing protocols are gaining popularity due to their event driven nature day by day. In this vary paper, reactive routing is studied precisely. Route request, route reply and route maintenance phases are modeled with respect to control overhead. Control overhead varies with respect to change in various parameters. Our model calculates these variations as well. Besides modeling, we chose three most favored reactive routing protocols as Ad-Hoc on Demand Distance Vector (AODV), Dynamic Source Routing (DSR) and Dynamic MANET on Demand (DYMO) for our experiments. We simulated these protocols using ns-2 for a detailed comparison and performance analysis with respect to mobility and scalability issues keeping metrics of throughput, route delay and control over head. Their performances and comparisons are extensively presented in last part of our work.
... WBAN supports a variety of innovative applications in both medical and non-medical sciences. In the field of medical sciences, sensor nodes are positioned on the physique of the patient to detect symptoms of various major illnesses like cancer, asthma and additionally to observe standard physiological parameters [12,13]. Also, in the entertainment industry, various secured applications in the non-medical domain have also seen WBAN as a rising technology. ...
... The database which contains the recorded information is applied to the classification of rules, out of which the best rule is selected for further analysis by medical entities. 13 Sharma et al. [95] By considering five different forwarding functions depending on distance between nodes, residual energy, and dissipated energy of the nodes, the proposed protocol provides 6.7% better throughput as compared to iM-SIMPLE protocol and longer lifetime. 14 Ambigavathi, et al. [96] The aim is to provide both energy efficient, balanced load and priority-based algorithm for the developed protocol ELBPQA (Energy efficient and load balanced priority queue algorithm in which the traffic has been divided into three categories. ...
Article
Full-text available
Background The increased cost of treatments in the health care industry and advancements in technologies have led to a promising area of development in Wireless Sensor Networks and semiconductor technologies. Wireless Body Area Networks is a subset of WSN in which sensor nodes are placed on the human body or implanted inside the body to determine various physical parameters of the human body. This information is forwarded to the medical centers or central servers through gateways. The direct advantage of this technology is the existence of portable health monitoring applications as well as location independent monitoring applications. But, still, the existence of smart hospitals needs a lot of focused research related to practical problems faced by patients as well as practitioners. Introduction The aim of this paper is to present an essential depiction of WBAN development in both medical and non- medical applications. The important features of various wireless technologies supported by WBAN have also been presented. It is apparent that to determine the overall performance of a network in terms of different parameters like temperature, power consumption, throughput and delay, etc., a significant role is played by the routing protocols. Since WBAN directly deals with the human body and hence implementation of a new protocol is a challenging task before researchers, this paper reviews each category of routing protocols and their corresponding limitations. A comparison among routing protocols will guide researchers in implementing a specific protocol for targeted application. The paper also focuses on the future of WBAN which will provide the research areas for further exploration. Conclusion It is found that QoS aware protocols are employed specifically for critical applications. If we consider radiation imparted from the sensors and tissue protection of the human body, the thermal aware routing protocol is the solution. Another important conclusion of this paper is that the various protocols do not provide an optimal solution for selecting the forward node during routing and this solution primarily depends on the residual energy of the nodes and distance of the node from the sink. A study of protocols developed from 2004 onwards till date shows that implementation of WBAN using integration of IoT, EoT, and fog computing has been the emerging topic of research in recent years.
... These benefits provide a convenient-environment that can monitor the daily lives and medical situations of patients at anytime, anywhere and without limitations [10,11]. On the other hand, one of the most important challenges to these new technologies in healthcare is the security and privacy issues that often makes a patient's privacy more vulnerable [12,13]. The patient's physiological vital signs are very sensitive, especially if a patient is suffering from an embarrassing disease. ...
... Lack of tracking methods could let an attacker to transmit improper details such as, by replying with a fake signal about the patient's location [19,20,24]. Authors in [12] discussed about localization systems and their attacks. 9. Accountability: In the medical field, it is necessary for healthcare providers to safe guard patient health information. ...
Article
Wireless Body Area Network (WBAN) is a new trend in the technology that provides remote mechanism to monitor and collect patient’s health record data using wearable sensors. It is widely recognized that a high level of system security and privacy play a key role in protecting these data when being used by the healthcare professionals and during storage to ensure that patient’s records are kept safe from intruder’s danger. It is therefore of great interest to discuss security and privacy issues in WBANs. In this paper, we reviewed WBAN communication architecture, security and privacy requirements and security threats and the primary challenges in WBANs to these systems based on the latest standards and publications. This paper also covers the state-of-art security measures and research in WBAN. Finally, open areas for future research and enhancements are explored.
... Authors in [7], [8], [9], [10] and [11] work on MAC layer of the OSI model and give a medium access control protocol for WBAN, give a through survey on energy efficient protocols for WBAN, present arm mobility for patients in WBAN, noise filtering for WBAN channel and provide localization technique for WBAN, respectively. N.S.A. Zulkifli et al. implement heart rate monitoring algorithm for players, performing strenuous exercises [12]. ...
Article
Wireless Body Area Sensor Network (WBASN) is a technology employed mainly for patient health monitoring. New research is being done to take the technology to the next level i.e. player's fatigue monitoring in sports. Muscle fatigue is the main cause of player's performance degradation. This type of fatigue can be measured by sensing the accumulation of lactic acid in muscles. Excess of lactic acid makes muscles feel lethargic. Keeping this in mind we propose a protocol \underline{TH}reshold based \underline{E}nergy-efficient \underline{FA}tigue \underline{ME}asurement (THE-FAME) for soccer players using WBASN. In THE-FAME protocol, a composite parameter has been used that consists of a threshold parameter for lactic acid accumulation and a parameter for measuring distance covered by a particular player. When any parameters's value in this composite parameter shows an increase beyond threshold, the players is declared to be in a fatigue state. The size of battery and sensor should be very small for the sake of players' best performance. These sensor nodes, implanted inside player's body, are made energy efficient by using multiple sinks instead of a single sink. Matlab simulation results show the effectiveness of THE-FAME.
... A lot of work is carried which focuses on energy efficiency optimization problem in WSNs (e.g. [7, 11, 16, 9] ). Different types of ECCs are investigated in [3] and based upon BER and power consumption criteria, Reed Solomon code RS(31, 21) is considered to be an appropriate choice. ...
Conference Paper
Due to small size of sensor nodes deployed in Wireless Sensor Networks (WSNs), energy utilization is a key issue. Poor channel conditions lead to retransmissions and hence, result in energy wastage. Error control strategies are usually utilized to accommodate channel impairments like noise and fading in order to optimize energy consumption for network lifetime enhancement. Meanwhile, cooperative communication also emerges to be an appropriate candidate to combat the effects of channel fading. Energy efficiency of cooperative scheme when applied with Automatic Repeat Request (ARQ), Hybrid-ARQ (HARQ) and Forward Error Correction (FEC) is investigated in this work. Moreover, the expressions for energy efficiency of Direct Transmission, Single Relay Cooperation and Multi Relay Cooperation are also derived. In all, our work is focused towards energy optimal communication in WSNs. Our results show that error control strategies along with the cooperative scheme significantly enhances system performance in the form of energy optimization.
... Recent research in WSNs mostly deals with the aim to maximize energy efficiency ( [1], [2]). In this regard, some authors worked at routing layer ( [3], [4], [5]) while others ( [6], [7], [8]) explored MAC layer. ...
Article
One of the major challenges in Wireless Body Area Networks (WBANs) is to prolong the lifetime of network. Traditional research work focuses on minimizing transmit power, however, in the case of short range communication the consumption power in decoding is significantly larger than transmit power. This paper investigates the minimization of total power consumption by reducing the decoding power consumption. For achieving a desired Bit Error Rate (BER), we introduce some fundamental results on the basis of iterative message-passing algorithms for Low Density Parity Check Code (LDPC). To reduce energy dissipation in decoder, LDPC based coded communications between sensors are considered. Moreover, we evaluate the performance of LDPC at different code rates and introduce Adaptive Iterative Decoding (AID) by exploiting threshold on the number of iterations for a certain BER. In iterative LDPC decoding, the total energy consumption of network is reduced by 20 to 25 percent.
... For many healthcare applications, it is essential to know about patient's location. A study of location confirmed is proposed in [10] that the author very concerns the leakage of patient location when wearable sensors sending data to remote medical center. Lu et al. [11] propose a new secure and privacy preserving opportunistic computing scheme SPOC, which each medical user in emergency can achieve the user-centric privacy access control to balance the high-reliability of PHI access and minimizing PHI privacy disclosure. ...
Article
Full-text available
With the pervasiveness of smart phones and the advance of wireless body sensor network (BSN), mobile Healthcare (m-Healthcare), which extends the operation of Healthcare provider into a pervasive environment for better health monitoring, has attracted considerable interest recently. However, the flourish of m-Healthcare still faces many challenges including information security and privacy preservation. In this paper, we propose a secure and privacy-preserving framework combining with multilevel trust management. In our scheme, smart phone resources including computing power and energy can be opportunistically gathered to process the computing-intensive PHI (personal health information) during m-Healthcare emergency with minimal privacy disclosure. In specific, to leverage the PHI privacy disclosure and the high reliability of PHI process and transmission in m-Healthcare emergency, we introduce an efficient lightweight encryption for those users whose trust level is low, which is based on mix cipher algorithms and pair of plain text and cipher texts, and allow a medical user to decide who can participate in the opportunistic computing to assist in processing his overwhelming PHI data. Detailed security analysis and simulations show that the proposed framework can efficiently achieve user-centric privacy protection in m-Healthcare system.
... There are many proactive routing protocols in literature (e.g [38], [39], [40], [41]).Whenever a network with proactive routing protocols initiates, route calculation for every possible destination also initiates at that vary time. Contrary to reactive routing in [42], [43], [44], proactive routing doesn't wait for a request to search some destination. ...
Article
To ensure seamless communication in wireless multi-hop networks, certain classes of routing protocols are defined. This vary paper, is based upon proactive routing protocols for Wireless multihop networks. Initially, we discuss Destination Sequence Distance Vector (DSDV), Fish-eye State Routing (FSR) and Optimized Link State Routing (OLSR), precisely followed by mathematical frame work of control overhead regarding proactive natured routing protocols. Finally, extensive simulations are done using NS 2 respecting above mentioned routing protocols covering mobility and scalability issues. Said protocols are compared under mobile and dense environments to conclude our performance analysis.
... A lot of work is carried which focuses on energy efficiency optimization problem in WSNs (e.g. [7, 11, 16, 9] ). Different types of ECCs are investigated in [3] and based upon BER and power consumption criteria, Reed Solomon code RS(31, 21) is considered to be an appropriate choice. ...
Article
Due to small size of sensor nodes deployed in Wireless Sensor Networks (WSNs), energy utilization is a key issue. Poor channel conditions lead to retransmissions and hence, result in energy wastage. Error control strategies are usually utilized to accommodate channel impairments like noise and fading in order to optimize energy consumption for network lifetime enhancement. Meanwhile, cooperative communication also emerges to be an appropriate candidate to combat the effects of channel fading. Energy efficiency of cooperative scheme when applied with Automatic Repeat Request (ARQ), Hybrid-ARQ (HARQ) and Forward Error Correction (FEC) is investigated in this work. Moreover, the expressions for energy efficiency of Direct Transmission, Single Relay Cooperation and Multi Relay Cooperation are also derived. In all, our work is focused towards energy optimal communication in WSNs. Our results show that error control strategies with cooperative schemes can significantly enhance system performance in form of energy optimization.
Article
One of the major challenges in Wireless Body Area Networks (WBANs) is to prolong the lifetime of network. Traditional research work focuses on minimizing transmit power; however, in the case of short range communication the consumption power in decoding is significantly larger than transmit power. This paper investigates the minimization of total power consumption by reducing the decoding power consumption. For achieving a desired Bit Error Rate (BER), we introduce some fundamental results on the basis of iterative message-passing algorithms for Low Density Parity Check Code (LDPC). To reduce energy dissipation in decoder, LDPC based coded communications between sensors are considered. Moreover, we evaluate the performance of LDPC at different code rates and introduce Adaptive Iterative Decoding (AID) by exploiting threshold on the number of iterations for a certain BER (0.0004). In iterative LDPC decoding, the total energy consumption of network is reduced by 20 to 25%.
Conference Paper
Critical role is being played by data related handling in providing efficient working environment for any organization or system. The Tracking related services are being used by various persons and organizations for facilitating day to day working of business. The continuous work and research has done by service providers and researchers for providing exact and efficient information to users of Vehicle Tracking Systems. This is a well known fact that the information can be generated through related and valid data. The need is to handle the received data carefully so that the users could get relevant and exact information. This paper is an attempt for presenting an approach to data handling and tracking of vehicle by using SPSS (A Statistical Tool). The overall scenario starting from data received through GPS device to tracking of the vehicle with position and movement through SPSS is being reflected in this paper.
Article
Viral diseases continue to emerge and annually bring challenges to the Brazilian public health system, such as COVID-19 with easy respiratory infection. This study aims to analyze the importance of new technologies in the treatment of COVID-19 and, thus, promote the information of technological data in the Brazilian territory. Therefore, methodological techniques were used in systematic reviews in the selection of included studies to be used in the construction of this short and critical systematic review. And 08 articles were included for inclusion in this critical analysis.
Chapter
Wireless Body Area Sensor Networks (WBANs) are becoming more and more popular and have shown great potential in real-time monitoring of the human body. With the promise of cost effective, unobtrusive, and unsupervised continuous monitoring, WBANs have attracted a wide range of monitoring applications such as healthcare, sport activity and rehabilitation systems. However, in using the advantage of WBANs, a number of challenging issues should be resolved. Besides open issues in WBANs such as standardization, energy efficiency and Quality of Service (QoS), security and privacy issues are one of the major concerns. Since these wearable systems control life-critical data, they must be secure. Nevertheless, addressing security in these systems faces some difficulties. WBANs inherit most of the well known security challenges from Wireless Sensor Networks (WSN). However, typical characteristics of WBANs, such as severe resource constraints and harsh environmental conditions, pose additional unique challenges for security and privacy support. In this chapter, we will survey major security and privacy issues and potential attacks in WBANs. In addition, we will explain an unsolved quality of service problem which has great potential to pose a serious security issues in WBANs, and then we discuss a potential future direction.
Conference Paper
Wireless Body Area Networks is a research field expanding quickly due to increased global demand for body worn electronics. In some cases measurements taken by these devices may seem odd, due to the unknown context in which they are taken. Localisation is a step towards greater context awareness about devices being worn, and an alternate solution to localisation using inertial measurements is used. The implementation makes use of MEMS technology to measure motion and determine the device location based on the measured signal. This approach is capable of determining the device location with up to 97% accuracy even when differentiating between left and right body parts.
Article
Viruses will continue to emerge and bring challenges to the global public health system with emerging viruses through respiratory contagion that cause pandemics. This study aims to propose a way to use constant monitoring during the period of treatment of the patient with COVID-19 and, thus, reduce the negative indicators of death in the Brazilian territory. Methodological techniques were used in meta-analysis and systematic reviews in the selection of included studies when used in the construction of this systematic review. 05 articles were selected for inclusion in this critical analysis.
Article
The accurate and efficient localization of a person equipped with wireless body area network (WBAN) is still a major issue in surveillance systems. Localization mechanisms using signal strength suffer from inaccuracy but those especially based on fingerprints are likely more accurate for indoor environment and some related mechanisms have been proposed. However, a simple and accurate mechanism is still unavailable for indoor environment except those using ultra wideband technology which is not yet implemented in all existing devices. This paper proposes a new mechanism based on fingerprinting for WBAN indoor localization named Kriged Fingerprinting. From the recorded data, this proposed model generates a huge unsaved database used to estimate the mobile node. It is a hybridism of fingerprinting, particle swarm optimization (PSO) and kriging. The fingerprinting method operates into two phases: the first is the training phase that serves to build a radio map in a database and the second phase is a matching phase. PSO is used as a matching algorithm and when a particle gets to an unrecorded location, the kriging mechanism is used to interpolate its locations values. In comparison with some works done for indoor localization mechanisms and based on fingerprinting, our proposal outperforms all in terms of accuracy: the mobile node is localized with a mean error value of 0.906 m. Hence, the kriging method brings more improvement in localization based on fingerprinting.
Article
Full-text available
Existing researches on location tracking focus either entirely on indoor or entirely on outdoor by using different devices and techniques. Several solutions have been proposed to adopt a single location sensing technology that fits in both situations. This paper aims to track a user position in both indoor and outdoor environments by using a single wireless device with minimal tracking error. RSSI (Received Signal Strength Indication) technique together with enhancement algorithms is proposed to cater this solution. The proposed RSSI-based tracking technique is divided into two main phases, namely the calibration of RSSI coefficients (deterministic phase) and the distance along with position estimation of user location by iterative trilateration (probabilistic phase). A low complexity RSSI smoothing algorithm is implemented to minimize the dynamic fluctuation of radio signal received from each reference node when the target node is moving. Experiment measurements are carried out to analyze the sensitivity of RSSI. The results reveal the feasibility of these algorithms in designing a more accurate real-time position monitoring system.
Conference Paper
Full-text available
Research in location determination for GSM phones has gained interest recently as it enables a wide set of location based services. RSSI-based techniques have been the preferred method for GSM localization on the handset as RSSI information is available in all cell phones. Although the GSM standard allows for a cell phone to receive signal strength information from up to seven cell towers, many of today's cell phones are low-end phones, with limited API support, that gives only information about the associated cell tower. In addition, in many places in the world, the density of cell towers is very small and therefore, the available cell tower information for localization is very limited. This raises the challenge of accurately determining the cell phone location with very limited information, mainly the RSSI of the associated cell tower. In this paper we propose a Hidden Markov Model based solution that leverages the signal strength history from only the associated cell tower to achieve accurate GSM localization. We discuss the challenges of implementing our system and present the details of our system and how it addresses the challenges. To evaluate our proposed system, we implemented it on Android-based phones. Results for two different testbeds, representing urban and rural environments, show that our system provides at least 156% enhancement in median error in rural areas and at least 68% enhancement in median error in urban areas compared to current RSSI-based GSM localization systems.
Article
Full-text available
Wireless Body Area Network(WBAN) is an emerging trend in ubiquitous society and very prolific for Human being, which consists of low power wireless biosensors, seamlessly placed on or implanted in human body in order to provide an adaptable and smart healthcare system. Positioning of a WBAN user in his/her critical condition is an important issue in WBAN. For this purpose we have canvassed different positioning system, checked advantage and disfavor of those system keeping eyes on the environment of WBAN.A patient equipped with WBAN sensors can stuck into any critical condition anywhere so it is important to monitor them continuously. There are different technologies for localization, but their stickiness with certain application does not make them unanimous. In WBAN we need a technology which can serve two way communication as well as positioning of the user. Since GSM technology is dispersed through worldwide with huge infrastructure so this work tries to elaborate that how GSM is better option than others.
Article
Full-text available
Research in location determination for GSM phones has gained interest recently as it enables a wide set of location based services. RSSI-based techniques have been the preferred method for GSM localization on the handset as RSSI information is available in all cell phones. Although the GSM standard allows for a cell phone to receive signal strength information from up to seven cell towers, many of today's cell phones are low-end phones, with limited API support, that gives only information about the associated cell tower. In addition, in many places in the world, the density of cell towers is very small and therefore, the available cell tower information for localization is very limited. This raises the challenge of accurately determining the cell phone location with very limited information, mainly the RSSI of the associated cell tower. In this paper we propose a Hidden Markov Model based solution that leverages the signal strength history from only the associated cell tower to achieve accurate GSM localization. We discuss the challenges of implementing our system and present the details of our system and how it addresses the challenges. To evaluate our proposed system, we implemented it on Androidbased phones. Results for two different testbeds, representing urban and rural environments, show that our system provides at least 156% enhancement in median error in rural areas and at least 68% enhancement in median error in urban areas compared to current RSSI-based GSM localization systems Comment: 6 pages, 5 figures, submitted to ICC 2010
Article
Full-text available
Context-aware applications have been gaining huge interest in the last few years. With cell phones becoming ubiquitous computing devices, cell phone localization has become an important research problem. In this paper, we present CellSense, a prob- abilistic RSSI-based fingerprinting location determina- tion system for GSM phones.We discuss the challenges of implementing a probabilistic fingerprinting local- ization technique in GSM networks and present the details of the CellSense system and how it addresses the challenges. To evaluate our proposed system, we implemented CellSense on Android-based phones. Re- sults for two different testbeds, representing urban and rural environments, show that CellSense provides at least 23.8% enhancement in accuracy in rural areas and at least 86.4% in urban areas compared to other RSSI-based GSMlocalization systems. This comes with a minimal increase in computational requirements. We also evaluate the effect of changing the different system parameters on the accuracy-complexity tradeoff. Comment: 6 pages, 6 figures, Submitted to Globe-com 2010
Article
Full-text available
Location awareness among the participating nodes is one of the crucial requirements in designing ofsolutions for various issues related to Wireless Sensor Networks (WSNs). This paper discusses about arange free localization mechanism for WSN that operate in a three dimensional space. in this scheme, thesensor network is supposed to be comprised of mobile and static sensor nodes. Mobile sensor nodes areassumed to be equipped with GPS enabled devices and are expected to be aware of their position at anyinstance. These mobile nodes move in the network space and periodically broadcast beacon messagesabout their location. Static sensor nodes receive these messages as soon as they enter the communicationrange of any mobile node. On receiving such messages the static nodes calculate their individual positionbased on the equation of sphere. The proposed scheme gains in terms of computational and memoryoverhead as compared to existing approaches. The proposed scheme is simulated using Sinalgo, and theperformance of this is compared with the chord selection approach. The simulation results validate thegain in localization time, its accuracy, and the resulted overhead.
Chapter
This chapter provides an overview of the probability theory. To master both the model building and the subsequent analysis of the probability models, one must have certain knowledge of basic probability theory. The chapter presents an experiment where the sample space is S. For each event E of the sample space S, a number P(E) is assumed that satisfies the following three conditions: (1) 0 ≤ P(E) ≤ 1; (2) P(S) = 1; and (3) for any sequence of events E1, E2, … that are mutually exclusive, that is, events for which En Em = φ when n ≠ m, then P (n) = (En).
Article
Sensor's localization plays a very important role in wireless sensor networks, a new sensor localization approach with Ring Overlapping Based on Received Signal Strength Indicator (ROBRSSI) using three beacons is presented. Through the designing of error transforming and the collaboration between nodes, the effect of measurement error of RSSI on localization accuracy is restrained efficaciously, the requirement of the relative position between node and beacons is reduced and the node's precise localization is achieved. Then the localization of new comer who is added into WSN to compensate for the node fail to work is studied on the basis of ROBRSSI. Simulation results show that the location accuracy is well and the localization percentage is satisfactory; the localization method of new comer in WSN is efficient, which achieves precise localization.
Conference Paper
With the evolution of wireless sensor network, body area sensor networks are expected to realize many realtime monitoring applications. Localization is one of the most important amongst all contexts. In indoor environments signal strength-based localization algorithms usually fail to achieve good accuracy due to deficient antenna coverage and multi- path interference. We propose spatial diversification method, which solves this problem by combining multiple receivers in a body area sensor network to estimate the location with a higher accuracy. This method mitigates the errors caused by antenna orientations and beam forming properties. With a range free localization algorithm that we developed, we show with experimental results that with spatial diversity the localization accuracy is improved compared to using single receiver alone.
Article
An improved DIOS (desorption ionization on porous silicon) method for laser desorption/ionization mass spectrometry (LDI MS) by electroless plating of silver nanoparticles (AgNPs) on porous silicon (PSi) was developed. By addition of 4-aminothiophenol (4-ATP) into the AgNO3 plating solution, the plating speed can be slowed down and simultaneously 4-ATP self-assembled monolayers (SAMs) on AgNPs (4-ATP/AgNPs) were formed. Both AgNPs and 4-ATP/AgNPs coated PSi substrates present much higher stability, sensitivity and reproducibility for LDI MS than the un-treated porous silicon ones. Their shelf life in air was tested for several weeks to a month and their mass spectra still displayed the same high quality and sensitivity as the freshly prepared ones. And more 4-ATP SAMs partly play a role of matrix to increase the ionization efficiency. A small organic molecule of tetrapyridinporphyrin (TPyP), oligomers of polyethylene glycol (PEG 400 and 2300), and a peptide of oxytocin were used as examples to demonstrate the feasibility of the silver-plated PSi as a matrix-free-like method for LDI MS. This approach can obtain limits of detection to femtomoles for TPyP, subpicomoles for oxytocin, and picomoles for PEG 400 and 2300, comparable to the traditional matrix method and much better than the DIOS method. It simplifies the sample preparation as a matrix-free-like method without addition of matrix molecules and homogenizes the sample spread over the spot for better and more even mass signals.
Conference Paper
With the increase in demand for ad hoc networks, localization has become a fundamental and essential solution to manage networks. Among existing localization algorithms, DV-Hop algorithm can estimate the location of nodes using the estimated distance of nodes without any additional devices to measure range information. However, DV-Hop is not accurate in estimating the geographic location of nodes because the average size for one hop is calculated without considering the positioning error and the path configuration between nodes. In this paper, a novel algorithm based on DV-Hop algorithm is proposed for the approach to estimating the average size of a hop by minimizing anchor's positioning error using Least Squares Estimation with other anchors. Moreover, unknown nodes have their own average hop size for one hop to alleviate the location error of the unknown occurring as more than the minimum hop count for the distance. Simulation results show that the proposed algorithm outperforms the DV-Hop algorithm in location estimation.
Article
Wireless Body Area Network (WBAN) has been recently promoted to monitor the physiological parameters of patient in an unobtrusive and natural way. This paper towards to make advantage of those ongoing wireless communication links between the body sensors to provide estimated position information of patients or particular body area networks, which make daily activity surveillance possible for further analysis. The proposed particle filtering based localization algorithm just picks up the received radio signal strength information from beacons or its neighbors to infer its own pose, which do not require additional hardware or instruments. Theoretical analysis and simulation experiments are presented to examine the performance of location estimating method.
Conference Paper
While the patients in particular hospital or home area are monitored by wireless body sensor networks, tracking service is also very necessary in some cases. This paper is exploring the ability of wireless body sensor to provide localization service. By concerning with the existing transmission power aware MAC protocol, we propose a localization algorithm based on particle filtering. Further, a general message passing framework of transmission power aware medium access control (MAC) is introduced to the tracking service seamlessly. The proposed particle filtering based localization algorithm just picks up the received radio signal strength information from beacons or its neighbors to infer its own pose, which do not require additional hardware or instruments. Theoretical analysis and simulation experiments are presented to examine the performance of location estimating method.
Conference Paper
Sensor localization has become an essential requirement for realistic applications over wireless sensor networks (WSN). Radio propagation irregularity and the stringent constraint on hardware cost, however, make localization in WSN very challenging. Range-free localizations are more appealing than range-based ones, since they do not depend on received signal strength to estimate distance and thus need simple and cheap hardware only. In this paper, we propose a ring-overlapping, range-free approach using the Ring Overlapping based on Comparison of Received Signal Strength Indicator (ROCRSSI). Simulation results have verified the high estimation accuracy achieved with ROCRSSI.
CellSense: A Probabilistic RSSI-based GSM Positioning System" IEEE Communications Society subject matter experts for publication in IEEE Globecom
  • M Ibrahim
M. Ibrahim, et al., "CellSense: A Probabilistic RSSI-based GSM Positioning System" IEEE Communications Society subject matter experts for publication in IEEE Globecom 2010.
Indoor Patient Estimation Using Particle Filtering and Wireless Body Area Sensor Networks
  • H Ren
H. Ren, et al., "Indoor Patient Estimation Using Particle Filtering and Wireless Body Area Sensor Networks", in Proceedings of the 29th Annual International Conference of the IEEE EMBS, Lyon, France, 2007.
The Localization Method with Ring Overlapping Based on Received Signal Strength Indicator for Wireless Sensor Networks
  • W Qu
W. Qu, et al., "The Localization Method with Ring Overlapping Based on Received Signal Strength Indicator for Wireless Sensor Networks", 2nd International Conference on Power Electronics and Intelligent Transportation System, 2009.