1,720,969 research outputs found
A Reconfigurable Differential CMOS RF Energy Scavenger With 60% Peak Efficiency and -21dBm Sensitivity
No full textA differential RF-DC CMOS converter for RF energy scavenging based on a reconfigurable voltage rectifier topology is presented. The converter efficiency and sensitivity are optimized thanks to the proposed reconfigurable architecture. Prototypes realized in 130nm provide a regulated output voltage of ~2V when working at 868MHz, with a -21dBm sensitivity. The circuit efficiency peaks at 60%, remaining above the 40% for a 18dB input power range
System With RF Power Delivery Capabilities for Active Safety Enhancement in Industrial Vehicles Using Interchangeable Implements
No full textIn this paper, an active system for safety enhancement in industrial and off-highway vehicles using interchangeable implements is presented. The system, applied to the real case study of automatic identification of implements connected to a telehandler, is developed by adopting a hardware–software codesign approach. It is comprised of two devices: the Illuminator-Gateway Device (IGD) and the End Device (ED). Differently from other similar solutions, the system embeds a complete radio frequency (RF) power delivery system that is compliant with the regulations in force in Europe and in North America to extend the battery lifetime of the ED. In particular, the IGD, positioned on the free end of the telescopic arm of the telehandler, supplies the RF energy required for the operations of the ED and acts as a gateway sending the data received from the ED to the other Electronic Control Units (ECUs) of the vehicle. The ED, instead, is mounted on the connected implement, collects the RF energy delivered by the IGD, and wirelessly sends the unique identifier, the key parameters, and the calculated effective working time of the implement. This information can be used by the main ECU of the vehicle for safety-related purposes and programmed maintenance. Experimental results show that the implemented RF power delivery system is able to gather up to 63% of the power required by the ED when it is on duty, thus significantly extending its battery lifetime
Optimized CMOS RF-DC converters for remote wireless powering of RFID applications
No full textIn this paper, we present for the first time a novel optimization procedure which allows to maximize the efficiency of RF-DC energy harvester converters, taking into account the contributions of the matching network. Thanks to this procedure, we have designed and realized a CMOS RF-DC converter operating in a very wide range of input power -14÷+1dBm with a peak efficiency of 45%. The RF-DC converter provides a constant output voltage ~2V in the whole input power range thanks to a smart voltage regulator integrated with the converter
A 868MHz CMOS RF-DC Power Converter With -17dBm Input Power Sensitivity and Efficiency Higher Than 40% Over 14dB Input Power Range
No full textIn this paper we present a novel CMOS RF-DC converter circuit, operating at 868MHz, for RFID and remote powering applications. The novel reconfigurable architecture of the converter allows the circuit to operate over a very wide input power range with very high efficiency compared with previous art works. Prototypes realized in STM 0.130ìm CMOS technology provide a regulated output voltage ~2V with a -17dBm input power sensitivity. The circuit efficiency, higher than 40% over a 14dB input power range, peaks at 60%
An Integrated RF Energy Harvester for UHF Wireless Powering Applications
No full textA RF energy harvester comprised of an integrated differential RF-DC converter and a differential PCB custom antenna is presented for wireless powering applications in the UHF band. The RF-DC converter, based on a reconfigurable voltage rectifier directly connected to a matched PCB antenna, is designed for high efficiency and sensitivity. Prototypes of the
RF-DC converter realized in CMOS 130nm technology show a
-16dBm sensitivity and a 60% peak efficiency. The RF-DC converters operate within the -16dBm÷0dBm input power range with an efficiency which remains above the 40% for more than 10dB. The RF energy harvester operates on the 840MHz÷975MHz band thanks to the ad-hoc designed wide-band differential antenna
Enhancing Safety in Vehicles with Implement or Trailer using an Autonomous Wireless Sensor Network System
No full textIn this paper, we present an autonomous wireless sensor network system to enhance safety in vehicles with connected implement or trailer. Today’s vehicle stability control algorithms are used to enhance safety and prevent accidents, but they do not take into account if a trailer or an implement is connected to the front/rear of the vehicle. The proposed system allows overcoming this limitation by advertising to the vehicle’ electronic control unit the presence of the connected implement. This allows the stability control algorithm adjusting the vehicles parameters to current real conditions. The developed system comprises two wireless devices: a Wireless Master Device (WMD), mounted on the vehicle, and an autonomous Wireless End Device (WED), installed on the connected implement or trailer. The WED gathers energy from implement’ or trailer’ natural vibrations by using a vibrational energy harvester and a piezoelectric transducer. Thus, avoiding the need of frequent battery replacement and leading the wireless system to autonomously work for several years
An autonomous wireless sensor network device powered by a RF energy harvesting system
No full textIn this paper, we present an energetically autonomous wireless sensor network (WSN) device designed to enhance safety in vehicles capable to connect extra gear/equipment to the main chassis. The proposed system allows the vehicle stability control system to automatically recognize the connected trailer or implement through a purposely designed WSN device, which is integrated into trailer /implement and wirelessly sends its identification number. The WSN device we developed integrates also a novel RF energy harvesting circuit which gathers the energy from an 868MHz RF signal source, which is purposely transmitted from the vehicle towards the trailer or implement for remote powering. Measurements performed on fabricated WSN system prototypes show that the RF harvester can gather up to ≈50uW@3m from the RF power source with efficiency higher than 30% over a range of 10dBm. The combination of the RF energy harvesting circuit with the ultra-low power architecture and a custom task manager designed for the WSN system allows to further increase primary battery lifetime, making the wireless system capable to operate autonomously for several years
Reconfigurable RF Energy Harvester with Customized Differential PCB Antenna
No full textIn this work, a RF Energy harvester comprised of a differential RF-DC CMOS converter realized in ST130nm CMOS technology and a customized broadband PCB antenna with inductive coupling feeding is presented. Experimental results show that the system can work with different carrier frequencies and thanks to its reconfigurable architecture the proposed converter is able to provide a regulated output voltage of 2 V over a 14 dB of RF input power range. The conversion efficiency of the whole system peaks at 18% under normal outdoor working conditions
Wireless self-powered transponders and multi-sensing unit to enable ISOBUS identification of mechanical implements
No full textIn this paper we present an ISOBUS-based system for the automatic identification of implements or trailers without electronics on board. This allows, firstly, to improve the pre-crash prevention because the performances of existing vehicle dynamics control systems can now take into account data coming from the implements or trailers connected to the tractor. Secondly, publishing on the ISOBUS network the information of all the implements, including the ones without electronics, permits a full deployment of precision farming techniques.
The absence of electrical or electronic equipment on implements forces the use of wireless solutions, which in turn are limited by their battery lifetime, which is not comparable with the typical lifetime of trailers or implements. To overcome this limiting factor we added energy harvesting capabilities to the developed transponder, which is able to store energy coming from mechanical vibrations occurring during the normal implement working conditions
Active Safety System with RF Energy Harvesting Capabilities for Industrial Applications using Interchangeable Implements
No full textIn this paper a system for the remote powering of low power electronic devices is presented. The system has been applied to a real industrial application allowing to enhance active safety in industrial vehicles. It is comprised of two main devices: i) the End Device (ED) with an embedded Radio Frequency (RF) energy harvester; ii) the Illuminator-Gateway Device (IGD) with an embedded RF power transmitter. Thanks to the optimization of the customized dual band Planar Inverted Folded Antenna (PIFA) used, the ULP architecture of the ED, the hardware-software co-design approach used and the optimization of the ED firmware, the proposed system is able to provide up to the 63% of the power required by the ED when it is on duty
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