A fully textile microstrip topology with ultra wideband (UWB) characteristics useful in wireless body area networks (WBAN) is proposed. The antenna is operable within the full UWB band and incorporates a full textile shielding ground plane. The full ground plane is shown to be crucial in maintaining the performance when worn on-body. It successfully reduces any on-body performance degradation, resulting in a very robust structure. A detailed numerical and experimental evaluation of the antenna is performed in free space and on body.

UWB All-Textile Antenna With Full Ground Plane for Off-Body WBAN Communications

Issues related to substrate noise in system-on-chip design are described including the physical phenomena responsible for its creation, coupling transmission mechanisms and media, parameters affecting coupling strength, and its impact on mixed-signal integrated circuits. Design guidelines and best practices to minimize the generation, transmission, and reception of substrate noise are outlined, and different modeling approaches and computer simulation methods used in quantifying the noise coupling phenomena are presented. Finally, experiments that validate the modeling approaches and mitigation techniques are reviewed

Substrate Noise Coupling in SoC Design: Modeling, Avoidance, and Validation

Efficiency in RF energy harvesting systems: A comprehensive review

Issues related to substrate noise in system-on- chip design are described including the physical phenomena responsible for its creation, coupling transmission mechanisms and media, parameters affecting coupling strength, and its impact on mixed-signal integrated circuits. Design guidelines and best practices to minimize the generation, transmission, and reception of substrate noise are outlined, and different modeling approaches and computer simulation methods used in quantifying the noise coupling phenomena are presented. Finally, experiments that validate the modeling approaches and mitigation techniques are reviewed.

Substrate Noise Coupling in SoC Design: Modeling, Avoidance, and Validation Studies of noise activity, in chip substrates that are shared by digital and analog circuits, are aiding efforts to reduce crosstalk and to model noise isolation schemes.

Electromagnetic energy harvesting holds a promising future for energizing low power electronic devices in wireless communication circuits. This article presents an RF energy harvesting system that can harvest energy from the ambient surroundings at the downlink radio frequency range of GSM-900 band. The harvesting system is aimed to provide an alternative source of energy for energizing low power devices. The system design consists of three modules: a single wideband 377› E-shaped patch antenna, a pi matching network and a 7-stage voltage doubler circuit. These three modules were fabricated on a single printed circuit board. The antenna and Pi matching network have been optimized through electromagnetic simulation software, Agilent ADS 2009 environment. The uniqueness of the system lies in the partial ground plane and the alignment of induced electric fleld for maximum current ∞ow in the antenna that maximizes the captured RF energy. The design and simulation of the voltage doubler circuit were performed using Multisim software. All the three modules were integrated and fabricated on a double sided FR 4 printed circuit board. The DC voltage obtained from the harvester system in the fleld test at an approximate distance of 50m from GSM cell tower was 2.9V. This voltage was enough to power the STLM20 temperature sensor.

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Design of RF energy harvesting system for energizing low power devices

This paper presents an optimization of the voltage doubler stages in an energy conversion module for Radio Frequency (RF) energy harvesting system at 900 MHz band The function of the energy conversion module is to convert the (RF) signals into direct-current (DC) voltage at the given frequency band to power the low power devices/circuits The design is based on the Villard voltage doubler circuit A 7 stage Schottky diode voltage doubler circuit is designed, modeled, simulated, fabricated and tested in this work Multisim was used for the modeling and simulation work Simulation and measurement were carried out for various input power levels at the specified frequency band For an equivalent incident signal of –40 dBm, the circuit can produce 3mV across a 100 k? load The results also show that there is a multiplication factor of 22 at 0 dBm and produces DC output voltage of 50 V in measurement This voltage can be used to power low power sensors in sensor networks ultimately in place of batteries

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Optimization of the Voltage Doubler Stages in an RF-DC Convertor Module for Energy Harvesting

In this study, a simple and compact ultra-wideband (UWB) patch antenna with rectangular slot is presented. The fabricated antenna consists of a rectangular patch tapered from a microstrip feeding structure and a truncated ground plane. The proposed antenna is etched onto a FR4 printed circuit board (PCB) with an overall size of 28 mm × 29 mm × 1.6 mm. Simulated and experimental results are compared and are shown to be in good agreement. Experimental results indicate that the antenna achieved an UWB impedance bandwidth (S11 < –10 dB) ranges from 3.8 to 12 GHz. The small antenna exhibits a good voltage standing wave ratio (VSWR) performance and its E– and H–plane radiation patterns are stable over the UWB frequency range. The simulated result shows that the designed antenna can achieve a gain between 1.5 and 4.5 dBi against frequency. Besides, the group delay is less than 0.4 ns over the operating frequency band. These characteristics make the designed antenna suitable for various UWB applications.

A compact microstrip antenna for ultra wideband applications

An Ultra Wideband (UWB) microstrip diamond slotted patch antenna with enhanced bandwidth is presented in this paper. The proposed antenna is simulated in CST Microwave Studio and fabricated for measurements. Its simulated result displays impedance bandwidth from 3.28 GHz to 19.64 GHz, whereas the measured result displays the frequency region from 2.01 GHz to 18.67 GHz. The antenna complies with the return loss of S11 < –10 dB and Voltage Standing Wave Ratio (VSWR) < 2 throughout the impedance bandwidth. Details of the antenna design and related results such as phase angle, input impedance and radiation patterns are discussed in this paper. This antenna has surpassed the bandwidth of UWB requirement, which is from 3.1 GHz to 10.6 GHz, and exhibits good UWB characteristics.

/pdf/ultra-wideband-microstrip-diamond-slotted-patch-antenna-with-a99yq2w1o6.pdf

Ultra Wideband Microstrip Diamond Slotted Patch Antenna with Enhanced Bandwidth

The design of voltage multiplier module used for energy harvesting system from ambient at downlink radio frequency range (9352 MHz-9598 MHz) of GSM-900 is presented The function of this voltage multiplier circuit is to convert the RF energy signal into DC voltage that can be used to energize the low power electronic devices The design was based on the Villard voltage multiplier circuit A 4-stage Schottky diode voltage multiplier circuit was designed, modeled, simulated, fabricated and tested for its performance Multisim was used for the modeling and simulation work Simulation and practical tests were carried out for various input power levels at the specified frequency band The RF input power levels verses the output voltages at the nodes of the Villard network were recorded The input for the voltage multiplier module was fed through an efficient matching network from an RF energy harvesting antenna which is designed at 377 Ω impedance For a received signal of −27dBm (199) μW at the antenna modules produce a DC output voltage of 21 V across 100 kΩ load

Chandan Kumar Chakrabarty

Papers

Design of RF energy harvesting system for energizing low power devices

Optimization of the Voltage Doubler Stages in an RF-DC Convertor Module for Energy Harvesting

A compact microstrip antenna for ultra wideband applications

Ultra Wideband Microstrip Diamond Slotted Patch Antenna with Enhanced Bandwidth

Design of an RF-DC conversion circuit for energy harvesting