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IEICE Transactions. 01/2012; 95-B:206-216.
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ABSTRACT: Simulations are widely used to design and evaluate new protocols and applications of indoor wireless networks. However, the available network simulation tools face the challenges of providing accurate indoor channel models, three-dimensional (3-D) models, model portability, and effective validation. In order to overcome these challenges, this paper presents a new CO-Simulation framework based on MATLAB and OMNeT++ (COSMO) to rapidly build credible simulations for indoor wireless networks. A hierarchical ad hoc passive RFID network for indoor tag locating is described as a case study, demonstrating the significance and efficiency of COSMO compared with other network simulators. COSMO surpasses other network simulators in terms of workload and validity.
Global Telecommunications Conference (GLOBECOM 2010), 2010 IEEE; 01/2011
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ABSTRACT: Current passive RFID systems face the challenges to locate mobile objects in real time in indoor environments, including the realization of low delay as well as effective cooperation among readers and accurate ranging ability in the physical layer. In order to overcome these challenges, this paper presents a low delay multi-reader passive RFID system using ultra high frequency (UHF) radio as the forward link from readers to tags and orthogonal time hopping pulse-position modulation (TH-PPM) impulse ultra-wideband radio (IR-UWB) over the dynamic framed slotted ALOHA algorithm as the backward link from tags to readers. The asymmetric radio links overlap parts of the forward and backward transmission and avoid reader-tag collisions. Readers cooperate via network synchronization by a server and a contention-based update strategy to acknowledge tags. An optimal system configured with 4 readers using 16 orthogonal TH sequences is suggested and operates 3 times faster than the theoretical potential of EPC Class-1 Generation-2 protocol with the listen-before-talk scheme.
Computer Communications and Networks (ICCCN), 2010 Proceedings of 19th International Conference on; 09/2010
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ABSTRACT: A mobile and wide area deployable wireless sensor system, including hardware and software, is developed to enhance the mobility, deployment and capability of wireless sensors for networked services. Due to the dual-layer dual-directional wireless communication capability of a novel WAN-SAN coherent architecture and the removal of fix-installed gateway, all sensor nodes are remotely controllable and seamlessly integrated to internet services. Hardware modules are optimized for ultra low power and compact size. Abstract and extendable application interface is developed, based on SMS and TCP/UDP protocol, to be integrated easily into existing service systems. Hierarchical GPS-LPS Adaptive Localization, is supported based on GPS, wireless cellular ID, RFID, IR-UWB and inertial prediction. Specific data compression technique is adopted for high density data source. Finally, Fresh Food Tracking service is presented as an application example, including some field test data.
Sensors, 2009 IEEE; 11/2009
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ABSTRACT: The rapid development of wireless sensor network and RFID technologies offers a wide range of novel applications and services. In this paper, we present a two-layered wireless network for warehouses and supermarkets to monitor goods storage and sale, and assist for quality management and market analysis. The hierarchical architecture uses IEEE 802.15.4a impulse ultra-wideband radio (IR-UWB) communication protocol between slave sensor nodes and master sensor nodes, and IEEE 802.11b/g between master sensor nodes and server. The performance of our proposal is evaluated based on the widely used OMNeT++ simulation environment. Simulation results are presented and discussed according to different sampling rates and traffic loads for specific scenarios requirements.
Mobile Ubiquitous Computing, Systems, Services and Technologies, International Conference on. 10/2009;
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ABSTRACT: An enhanced dual-layer wide area wireless sensor network (WSN) system was developed and applied in fresh food tracking application. The sensor nodes of WSN provide a set of useful measurements about the environmental conditions during the fresh food transportation. Since the 3-axis acceleration data in such application account for more than 99% out of all collected source data, we propose a novel acceleration data compression scheme for this specific application, to overcome the resource and cost limitation imposed on embedded sensing nodes and wireless communication links in WSN. According to general fresh food transport behavior pattern, the acceleration data can be extracted into three components (D waveform, A waveform and P waveform). Each component could be compressed separately according to its distinct characteristic and then packetized as an encoded frame. In this paper we examine the experimental acceleration dataset from a field test (fresh melon fruit transport from Brazil to Sweden in 20 days) as a test case. Experimental results show that a high compression ratio (around 10:1) with the acceptable distortion could be achieved, confirming the effectiveness of the compression scheme proposed in this work.
Electronic Measurement & Instruments, 2009. ICEMI '09. 9th International Conference on; 09/2009
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ABSTRACT: Internet of things technologies makes it possible to trace when and where the excellent food or wine is spoiled or loses perfect taste in logistics and retail. This paper describes a system using a two-layered wireless sensor network to monitor the supply chain from manufacturer to consumer, including the network topology, application software on server, and sensor node hardware. It employs GSM/GPRS as the high layer network and semi impulse ultra-wideband radio (IR-UWB) for the low layer communication. We propose GSM Cell-ID location technology for tracking the goods transportation, and time-of-arrival method for local positioning. Finally, the first version of the system implementation and future work are presented.
Networked Sensing Systems (INSS), 2009 Sixth International Conference on; 07/2009
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ABSTRACT: This paper presents an efficient programmable engine that supports diverse interpolation algorithm in different video coding standards, such as H.264/AVC, and the Chinese national standard, AVS. It is a VLIW(very long instruction word) and SIMD(single instruction multiple data) hybrid architecture which could issue four ALU operations and one memory reference or a branch operation in every clock cycle, and execute four different data streams in a single instruction. An 8-bank 2-D on-chip memory is proposed to improve the parallelism of memory accessing. The design is implemented with Verilog-HDL, and synthesized with synopsys tools using 0.18 um Standard Cell Library. The total area is about 3.80 x 4.31 mm<sup>2</sup>, and the frequency can achieve 179.5 MHz.
ASIC, 2007. ASICON '07. 7th International Conference on; 11/2007
