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Climate change and resultant scarcity of water are becoming major challenges for countries around the world. With the advent of Wireless Sensor Networks (WSN) in the last decade and a relatively new concept of Internet of Things (IoT), embedded systems developers are now working on designing control and automation systems that are lower in cost and more sustainable than the existing telemetry systems...
The demo illustrates the performance of energy detection spectrum sensing. Time domain energy detection will be shown. Spectrum sensing is crucial for Cognitive Radio Transceiver. The original system under-study in my work is based on a Continuous Time RF Delta Sigma modulator, In the demo — to have the whole concept validated using FPGA board — an emulation of the RF delta sigma modulator is used...
Radio frequency front-ends constitute a core part of both conventional and emerging communication systems. Yet, although hardware realizations practically suffer from several types of impairments that degrade the overall system performance, the corresponding effects are often neglected and transceivers are assumed ideal. This typically refers to effects that are typically related to amplier nonlinearities,...
Direct-conversion radio transceivers can offer reprogrammable and low-cost hardware solutions for full-duplex (FD) cognitive radio (CR) devices. However, they are susceptible to radio frequency (RF) impairments, such as in-phase (I) and quadrature (Q) imbalance (IQI), which can significantly constrain the spectrum sensing capabilities. This paper is devoted to quantify and evaluate the effects of...
Direct-conversion radio transceivers can offer reprogrammable and low-cost hardware solutions for full-duplex (FD) cognitive radio (CR) devices. However, they are susceptible to radio frequency (RF) impairments, such as in-phase (I) and quadrature (Q) imbalance (IQI), which can significantly constrain the spectrum sensing capabilities. This paper is devoted to quantify and evaluate the effects of...
We present a novel low-cost built-in test approach for the Error Vector Magnitude (EVM) performance of RF transceivers. We rely on built-in sensors to extract low-cost measurements that can be used thereafter to predict implicitly the EVM. The key attribute of the sensors is that they are non-intrusive, that is, they are not electrically connected to the RF transceiver. Hence, the proposed built-in...
Due to the proliferation of nanometer CMOS mixed-signal/RF circuits and a push towards high operating speeds (5–100 Ghz+), there has been renewed interest in the design of high-speed circuits and systems that can self-calibrate and self-heal post-manufacture and in the field. In the past, designers have invented self-healing mechanisms that are tailored towards specific (critical) mixed-signal/RF...
Cognitive Radio (CR) technology is one of the favorable technology to efficiently deploy the underutilized frequency spectrum. Currently, the Federal Communications Commission (FCC) allowed TV white space (TVWS) which should protect the licensed user communication to utilize for data communication. The first actual deployment of communication system operating on TVWS is implemented in our group. However,...
We study the feasibility of utilising the RF transceiver of a mobile device to establish some kind of situation awareness. Our results show that the analysis of channel characteristics can provide additional and sufficiently accurate context information. This situation awareness is cheap in the sense that it can be obtained from already ongoing communication in a network of nodes. In this paper we...
Clinically many methodologies, both invasive and non-invasive, have been applied on the assessment of intestinal function in vivo. In routine, there are two preferable non-invasive methods, including ultrasound imaging and stethoscope, to get insight of intestinal motility for clinical diagnosis. However, the operation of traditional monitors is relied on professionals' experience, and also the sensing...
This paper presents a SystemC-based system-level modeling framework for wireless sensor networks. Benefit from the advantages of SystemC in the aspect of hardware and software co-simulation, this modeling framework allows the performance evaluation of sensor networks at system-level with elaborate sensor node models. It is used to study an industrial application, in which an IEEE 802.15.4 sensor network...
Technology evolution have made possible to connect all kind of devices to IP network. This becomes an evident objective for sensors networks research. The IETF 6LoWPAN RFC proposal was developed in that sense to use the benefit of IPV6 over wirelessly connected sensors (WSN). The IEEE 802.15.4 MAC layer stack being popular in the domain of wireless sensors within constrained resources, a few 6LoWPAN...
Development of reconfigurable RF resembles the Quest for the Holy Grail. It was started a long time ago; interesting developments have been achieved but it looks like it will never finish. However, as more and more microelectronic markets are under intense pressure, the need for reconfigurable RF systems is constantly growing. This paper aims at describing all current evolutions which push towards...
Many applications of sensor networks require batteries as the energy source, and hence critically rely on energy optimisation of sensor batteries. But as often neglected by the networking community, most batteries are non-ideal energy reservoirs and can exhibit battery recovery effect - the deliverable energy in batteries can be replenished per se, if left idling for sufficient duration. We made several...
Cognitive radios are slated to be the next generation of smart transceivers that can opportunistically access spectrum through dynamic sensing of their immediate radio frequency (RF) environment. Such spectral sharing will be limited primarily by the interference that a cognitive user may potentially cause to the licensed primary user of the band. In particular, all cognitive transmitters located...
The RF transceivers in MILES are used to trigger firing or communicate informations about the conditions of soldier and weapons. These transceivers have characteristics of low data rate and low power consumption for short range communication on the human body. Therefore, ZigBee devices are the best candidates for this kind of application. Although a ZigBee device operates under very low radiation...
This paper describes the dynamic spectrum access radio system that was built as part of the DARPA XG program. The DSA system's architecture four principal components (the DSA engine; the environmental sensing (i.e., detection) subsystem; the communications (i.e., radio) subsystem; and a policy module/enforcer) are described. The DSA system's 802.16-based radio hardware is described. One of the field...
This paper presents an arcade video game platform with a natural and tangible interface. The platform is built upon position tracking and velocity computing systems. The position tracking system uses radio frequency transceivers and ultrasonic sensors to compute the 3D position of the game player. The velocity computing system uses the 2D coordinates of two infrared ray grids to compute the trajectory...
The paper introduces a model of wireless sensor network (WSN) nodes with SystemC-AMS, a C++ based language for system-level description, then presents model refinements and simulation improvements of the system. Firstly the paper details the components of a WSN node : a sensor, an ADC, a microcontroller and a RF transceiver with some introduced impairements. Secondly, it presents the implementation...
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