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A wireless sensor network equipped with microphones can be used for context awareness by classifying sound events in the target environment. This classification will become less accurate when more than one sound can be heard at the same time. We conduct a series of experiments in which we mix different sound types in order to see how high this influence is. We conclude, that in most cases, the classifier...
Indoor wireless transceivers connect sensors and actuators, which are carried by a mobile agent to the Smart Home Information System (SHIS). In the smart home, the sensors' role is to observe the human activities and home status, while the actuators are to perform assistive and recovery actions for serving the home resident. The SHIS then analyzes the sensors' data and issues the actuation commands...
Timely delivery of critical traffic is a major challenge in industrial applications. The Wireless Dominance (WiDOM) medium access control protocol offers a very large number of priority levels to suit time sensitive application requirements. In particular, assuming that its overhead is properly modeled, WiDOM enables an accurate evaluation of the network response time in the wireless domain, through...
Impulsive noise is one of the key factor that prevents millimeter waves frequencies wireless sensors system to be fully reliable in the railway environment. Measurements of impulsive noise taken in real railway environment are required to understand the behavior of the wireless sensors under these undesired fields. In this paper, impulsive events are extracted and characterized from the measured data...
This paper presents a 12-channel, low-power, high efficiency neural signal acquisition front-end for local field potential and action potential signals recording. The proposed neural front-end integrates low noise instrumentation amplifiers, low-power filter stages with configurable gain and cut-off frequencies, a successive approximation register (SAR) ADC, and a realtime compressed sensing processing...
There is a need to fulfill the growing capacity requirements of power line communication (PLC). One way to achieve higher data rates in PLC networks is to operate at higher frequencies and increase the used bandwidth. In the future, the increased PLC frequency range can overlap with several wireless communications systems resulting in interference for these transmissions and vice versa. Commonly used...
In this paper, the problem of fusion of decisions transmitted over Rayleigh fading channels in wireless sensor networks (WSNs) is revisited. The likelihood ratio test (LRT) is considered as the optimal fusion rule when applied at the fusion center. However, applying the LRT at the fusion center requires both the channel state information (CSI) and the local sensors performance indices. Acquiring these...
Among various cooperative techniques aiming to reduce power consumption for Wireless Sensor Network (WSN), we present a new approach, named distributed max-dmin precoding (DMP). This protocol is based on the deployment of a virtual 2×2 max-dmin precoding over one source, one forwarding relay, both equipped with one antenna and a destination involving 2 antennas. In this context, two kinds of relaying,...
In this paper, we propose a blind binary low-density parity-check (LDPC) encoder identification scheme for M-quadrature amplitude modulation (M-QAM) signals. The expectation-maximization (EM) algorithm is developed to estimate the unknown signal amplitude, noise variance, and phase offset for M-QAM signals. The a posteriori probabilities (APPs) of the coded bits are obtained from the APPs of the transmitted...
This paper reports an integrated 64-channel neural recording sensor. Neural signals are acquired, filtered, digitized and compressed in the channels. Additionally, each channel implements an auto-calibration mechanism which configures the transfer characteristics of the recording site. The system has two transmission modes; in one case the information captured by the channels is sent as uncompressed...
This paper presents a programmable wireless platform for biomedical signal acquisition application. The platform includes 8-channel programmable low-noise frontend circuits, a 12-bit SAR ADC, a digital control and processing unit (DCPU), and a RF transceiver. The number of the readout channels in the platform can be programmable according to the requirements of the applications. And the platform can...
Near-infrared spectroscopy (NIRS) is a relative new technology in monitoring muscle oxygenation and hemo-dynamics. This paper presents a portable multi-channel wireless NIRS device for real-time monitoring of muscle activity. The NIRS sensor is designed miniaturized and modularized, to make multi-site monitoring convenient. Wireless communication is applied to data transmission avoiding of cumbersome...
Compressed sensing (CS) technique has attracted a lot of recent research interests in mathematics and signal processing fields. Literature studies often exploit CS at the receiver side to sub-sample the receiving signals to reduce the sampling rate and processing overhead. It would be of great benefit if it is possible to exploit CS at the transmitter side to reduce the redundancy of the data before...
The live implantation of micro-electrode arrays allows the observation of populations of neural activity. There is a strong need for unsupervised adaptable neural spike extraction and spike-sorting methods, which would significantly reduce data throughput and allow for implantation and wireless transmission. We present a method for neural spike feature-extraction that involves the generation and use...
In this paper, geometry-based algorithms for device-free localization (DFL) of a single target are proposed. The algorithms exploit the change in attenuation caused by the device-free target on radio links passing through the deployment area. By solving for the intersections of some of the attenuated links and taking the centroid of the intersection points, an estimate of the target's location is...
The world population is in the midst of a unique and irreversible process of aging. Fall, which is one of the major health threats and obstacles to independent living of elders, will aggravate the global pressure in elders' health care and injury rescue. Thus, automatic fall detection is highly in need. Current proposed fall detection systems either need hardware installation or disrupt people's daily...
Bayesian estimation methods are widely used for wireless localization systems. They employ priori information and current measurement error distribution models to derive the state of a mobile target. Cramér-Rao lower bound (CRLB) is a fundamental tool to analyze the performance of Bayesian estimators. Although CRLB is derived based on the measurement error distribution, only a few works have investigated...
Efficient dynamic spectrum access (DSA) policies rely on accurate spectrum sensing information to exploit spectrum white space optimally. Obtaining accurate channel state information (CSI) from local spectrum measurements is made difficult by wireless signal fading and the presence of thermal noise which distorts measured signals and leads to uncertainty regarding the occupancy of spectrum resources...
Various control applications such as aerospace vehicles and automotive control systems can benefit from lower weight and cost. Replacing wired feedback control with wireless sensor and actuator networks (WiSAN) offers attractive features by improving upon the weight and cost problems, while posing new challenges due to the delayed noisy feedback links. Addressing these challenges requires modeling...
A novel approach involving selective channel signaling is proposed to achieve significant reductions in power requirements in OFDM. It is shown that by using only a subset of the available channels, savings in power can be achieved without sacrificing channel capacity.
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