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Abnormal activity sensing has attracted increasing research attention in military surveillance, patient monitoring, and health care of children and elderly, etc. Researchers have exploited the characteristics of wireless signals to sense “keystrokes” and “human talks”, relieving the privacy invasion concern caused by mounting the surveillance cameras or wearing the smart devices. However, existing...
We build an ubiquitous abnormal activity detection system, namely NotiFi, for accurately detecting the abnormal activities on commercial off-the-shelf (COTS) IEEE 802.11 devices. In contrast to the traditional wearable sensor based and computer vision based systems which require additional sensors or enough lighting in line-of-sight (LoS) scenario, we proceed directly with abnormal activity characterization...
Mobile communication networks are more and more characterized by the integration of distributed and centralized computing and storage resources. Big data capability thus available throughout such networks will not only deliver enhanced system performance, but also profoundly impact the design and standardization of the next-generation network architecture, protocol stack, signaling procedure, and...
Most recently, activity localization and recognition has increasingly attracted significant attentions due to its broad range of applications to support smart devices. Pioneer systems based on WiFi signals usually require six to eight antennas to localize the activity while the commodity WiFi infrastructure does not meet this requirement. In addition, they also require the priori learning of wireless...
Abnormal activity detection has recently drawn significant research attention, because of its potential applications in providing critical and severe emergency information. Existing non-invasive activity detecting approaches rely on radio signals, wearable sensors or specialized hardware. Motivated by the observation that the amplitude and the phase information of channel state information CSI are...
With the rapid development of internet of things (IoT) with various low-cost machine type communications (MTC) devices, intelligent wearable devices, vehicular sensors and environmental sensors etc, it's anticipated that trillions of wireless nodes in IoT with diversified applications and services may come to life in the fifth generation wireless communication system (5G). These devices, however,...
Electronic channel sounding plays a vital role in developing wireless communication systems. It is critical for transceivers' equalization and filtering operations. However, current pure electronic channel sounding techniques are not well-suited for emerging scenarios such as opportunistic spectrum access, channel impulse response (CIR) based wireless positioning, and wireless security applications,...
Wireless meter reading based on a combination of WIA wireless network technology and 4G wireless network technology is proposed. Data can be collected and transferred to the background processing center timely and accurate. The article describes WIA wireless network hardware design and software design process. Greatly saving cost of laying communication lines due to using the wireless communication...
In this paper we introduce a precise real-time 3D indoor localization concept using a combination of the MISAS (multilateral inverse synthetic aperture secondary radar) approach and particle filtering. The synthetic aperture approach is a promising locating technique with effective multipath suppression. However, the practical usage in real-time applications is limited by its huge computational load...
In this paper, we propose and develop a small-scale research platform for intelligent transportation systems. Our platform has four main parts: an arena; an indoor localization system; automated radio controlled (RC) cars; and roadside monitoring facilities. First, to mimic the traffic environments we build an arena with a wooden floor, mock buildings and streets. Second, for the indoor localization...
For body sensor networks (BSN) nodes, extending battery lifetime is one of the key problems. In this paper, we address the problems of designing battery-friendly packet transmission policies in order to maximize the lifetime of batteries for BSN nodes under certain delay and deadline constraints. We present local optimization scheme for slack time and evaluate it with respect to battery performance...
This paper presents a compact wireless sensor node for 3D motion sensing, which can be used in wearable computing research. The sensor node is based on a commercial orientation sensor module and a wireless communication module. To extend the lifetime of this motion sensor node in many wearable computing applications, a power management unit is designed and implemented, which consists of a micro controller...
Wireless grid is a wireless network based virtual system that consists of wireless-connected different types of electronic devices and computers. It has broad application prospects in e-learning, mobile e-business, modern healthcare, smart home, wireless sensor networks and disaster management. Wireless cloud is a natural extension of wireless grid. On the basis of a literature analysis, this paper...
In this paper, the time modulation technique is extended to circular antenna arrays. The TMSA is adopted to synthesize a flat-topped pattern and scanning sum beams with lower amplitude excitation dynamic-range ratios or even uniform amplitude excitations, as compared to those of the CSA. The studies show that TMCA is a promising approach in synthesizing flat-topped pattern or scanning sum patterns...
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