Design and Development of an RF Energy Harvesting Wireless Sensor Node (EH-WSN) for Aerospace Applications

AbstractNumerous applications of wireless sensor networks are constrained by the limited battery power of the sensors. The power consumption of processors and microcontrollers could be scaled down dramatically with the new advances in microelectronics. This reduction gives rise to the possibility of energy harvesting sources to power wireless sensor nodes. In this paper a summary is given of our ongoing research work on RF Energy Harvesting Wireless Sensor Node (EH-WSN) which can plug-in to the already developed Wireless Instrumentation System (WIS) for aerospace applications. Present WSN's which are powered from battery have limited operational lifetime. While energy harvesting has the potential to enable near-perpetual system operation, design of which is a complex trade-off due to the interaction of numerous factors such as the characteristics of the energy source, power supply requirements, power management futures, WSN application behaviour, chemistry and capacity of batteries used etc. In this work, we have identified a suitable power harvesting cum battery management scheme which harvests power consistently and deterministically from a secondary RF source which can be used even in harsh real-time applications. Using a RF power harvesting receiver IC and a compact power management cum storage circuit, we establish the test bed and conduct a series of experiments to verify the effectiveness of the proposed scheme. We have demonstrated continuous operation of the sensor node at an operating distance of 2 meters from the RF power source for a data rate of 240 sps. This is achieved by using special synchronized MAC protocol, low power techniques, usage of low leakage components and systematic coding of the micro controller firmware. This paper provides an insight into how various power reduction techniques can be used and orchestrated such that satisfactory performance can be achieved for a given energy budget

Parasitic capacitance characteristics of deep submicrometre grooved gate MOSFETs

10.1088/0268-1242/17/3/301Semiconductor Science and Technology173179-188SSTE

Simulation of 0.1μm hot carrier effect suppressed grooved gate MOSFET

International Symposium on IC Technology, Systems and Applications8490-49

Micro-Strain and Temperature Sensors for Space Applications with Graphite-PDMS Composite

Large-area flexible sensors have several applications [1]-[11]. In new generation aerospace systems, such flexible sensor sheets can be used to measure the spatial distribution of important parameters along the structure of launch-vehicles or space-crafts eg. Strain and temperature. Highly stretchable strains sensors have been developed using carbon-nanotube/PDMS composites [12], optical guides in PDMS [13], 3-D foam [14]. In [15], a method to adjust the sensitivity of strain sensors by tailoring the microstructure of graphene-aerogel/PDMS nanocomposite, in the strain range of 0 to 10%, has been discussed. Another work discusses flexible dual sensors (pressure and temperature) using microstructureframe-supported organic thermoelectric materials [16]. In this work, we investigate percolation based sensors with Graphite-PDMS (poly di-methyl siloxane) composites for measuring micro-strains and temperature. The concentration ratio of the graphite/elastomer and the dimensions, electrode spacing of the sensor have been experimentally optimized to operate the sensor in the micro-strain range (0-5000 μ.strain), which is of high interest in aerospace applications. The concentration ratio of Graphite/PDMS composite has been experimentally optimized as 0.46:0.54, and the PDMS Elastomer:Cross-linker ratio has been optimized as 4:1 to achieve sensitivity within this micro-strain range. Changes in both temperature and strain can be sensed by measuring the change in resistance across the electrodes of the sensing element. The fabrication methodology and the characterization measurements for micro-strain, temperature are further discussed in the subsequent sections

Field Programmable Gate Array Based Miniaturised Central Controller for a Decentralised Base-Band Telemetry System for Satellite Launch Vehicles

International Telemetering Conference Proceedings / October 30-November 02, 1995 / Riviera Hotel, Las Vegas, NevadaThe Central Control Unit (CCU) for a decentralised on-board base-band telemetry system is designed for use in launch vehicle missions of the Indian Space Research Organisation (ISRO). This new design is a highly improved and miniaturised version of an earlier design. The major design highlights are as follows: usage of CMOS Field Programmable Gate Array (FPGA) devices in place of LS TTL devices, high level user programmability of TM format using EEPROMs, usage of high density memory for on-board data storage and delayed data transmission, HMC based pre-modulation filter and final output driver etc. The entire system is realised on a single 6 layer MLB and is packaged on a stackable modular frame. This design has resulted in a 1:4 reduction in weight, 1:4 reduction in volume, 1:5 reduction in power consumption and 1:3 reduction in height in addition to drastic reduction of part diversity and solder joints and thus greatly increased reliability. This paper discusses the design approach, implementation details, tools used, simulations carried out and the results of detailed qualification tests done on the realised qualification model.International Foundation for TelemeteringProceedings from the International Telemetering Conference are made available by the International Foundation for Telemetering and the University of Arizona Libraries. Visit http://www.telemetry.org/index.php/contact-us if you have questions about items in this collection

FIELD PROGRAMMABLE GATE ARRAY BASED MINIATURISED REMOTE UNIT FOR A DECENTRALISED BASE-BAND TELEMETRY SYSTEM FOR SATELLITE LAUNCH VEHICLES

International Telemetering Conference Proceedings / October 30-November 02, 1995 / Riviera Hotel, Las Vegas, NevadaThe Remote Unit (RU) for a decentralised on-board base-band telemetry system is designed for use in launch vehicle missions of the Indian Space Research Organisation (ISRO). This new design is a highly improved and miniaturised version of an earlier design. The major design highlights are as follows. Usage of CMOS Field Programmable Gate Array (FPGA) technology in place of LS TTL devices, the ability to acquire various types of data like high level single ended or differential analog, bi-level events and two channels of high speed asynchronous serial data from On-Board Computers (OBCs), usage of HMC technology for the reduction of discrete parts etc. The entire system is realised on a single 6 layer MLB and is packaged on a stackable modular frame. This paper discusses the design approach, tools used, simulations carried out, implementation details and the results of detailed qualification tests done on the realised qualification model.International Foundation for TelemeteringProceedings from the International Telemetering Conference are made available by the International Foundation for Telemetering and the University of Arizona Libraries. Visit http://www.telemetry.org/index.php/contact-us if you have questions about items in this collection

Data acquisition and processing at ocean bottom for a Tsunami warning system

The design and development of a Bottom Pressure Recorder for a Tsunami Early Warning System is described here. The special requirements that it should satisfy for the specific application of deployment at ocean bed and pressure monitoring of the water column above are dealt with. A high-resolution data digitization and low circuit power consumption are typical ones. The implementation details of the data sensing and acquisition part to meet these are also brought out. The data processing part typically encompasses a Tsunami detection algorithm that should detect an event of significance in the background of a variety of periodic and aperiodic noise signals. Such an algorithm and its simulation are presented. Further, the results of sea trials carried out on the system off the Chennai coast are presented. The high quality and fidelity of the data prove that the system design is robust despite its low cost and with suitable augmentations, is ready for a full-fledged deployment at ocean bed. (C) 2013 Elsevier Ltd. All rights reserved