Transponder Devices Research Articles

Functionality of the Search and Rescue Transponder (SART) in Maritime Search and Rescue Actions

In this article, the authors present contemporary problems in search and rescue operations at sea. The research focuses on the detection of the SART (Search and Rescue Transponder) device. This device is used to call for help and assist the rescuing vessel in tracking. Issues with their functionality may reduce the likelihood of finding a survivor. The authors designed an experiment to assess the effectiveness of using the device. The research conducted is a real-world experiment that involved a ship radar, a liferaft, a SART device, and a radar reflector. The experiment consisted of multiple trials to detect, locate, and track the device, as well as to assess the radar image features. Four scenarios were developed, considering different distances and radar settings. Performance evaluation indicators were also developed. The results are presented both graphically and numerically. A brief discussion of the obtained results and concise conclusions are provided. Along with the research findings, recommendations for the use of SART and radar on ships are also presented, as well as recommendations for improving training. The results are applicable to improving the effectiveness of SAR operations.

Analysis of the effectiveness of methods for ensuring the reliability of a communication satellite transponder

Objectives . Since the launch of satellite communication systems in practical use, approaches towards enhancing their operational quality and durability have been developing in the direction of increased reliability of airborne transponders. This is mainly achieved by increasing redundancy and using components with a lower failure rate. In this regard, the creation of new technologies and new materials is a particularly promising direction. However, since durability testing of complex systems can take several years, the problem of ensuring an effective combination of redundancy methods and elements having a reduced failure rate remains challenging. The purpose of the work is to analyze the effectiveness of methods for ensuring the reliability of a communication satellite transponder based on a proposed methodology for determining the durability index using a mathematical model of the probability of failure-free operation. Methods . In order to describe the complex structure of a satellite communication system transponder, a logical- probabilistic method is used, in which the dependence of the system reliability indicators on the reliability indicators of the transponder elements is formulated as a logical function of operability. Mathematical models of system reliability are created on this basis including for redundant systems. Graphs and analytical methods are used to compare different systems. Results . The influence of various methods for ensuring the redundancy of transponder devices and the use of more reliable components on the reliability and durability indicators is considered. A gamma-percentage resource-based technique for determining the durability indicator based on the constructed mathematical models of the probability of failure-free operation is presented along with a comparative analysis of measures to increase the gamma-percentage resource of the transponder. Conclusions . The presented method for determining the durability index using a mathematical model of the probability of no-failure operation can be used to determine the time interval within which redundancy increases the probability of no-failure operation as compared with a decrease in the failure rate of elements. On this basis, the most effective combination of redundancy methods and approaches for reducing the failure rate of elements can be identified.

Retention and loss of PIT tags and surgically implanted devices in the Eurasian beaver

BackgroundPassive integrated transponder devices (PIT tags) are a valuable tool for individual identification of animals. Similarly, the surgical implantation of transmitters and bio-loggers can provide useful data on animal location, physiology and behavior. However, to avoid unnecessary recapture and related stress of study animals, PIT tags and bio-loggers should function reliably for long periods of time. Here, we evaluated the retention of PIT tags, and of very high frequency (VHF) transmitters and bio-loggers that were either implanted subcutaneously or into the peritoneal cavity of Eurasian beavers (Castor fiber).ResultsOver a 21-year period, we implanted PIT tags in 456 individuals and failed to detect a PIT tag at recapture in 30 cases, consisting of 26 individuals (6% of individuals). In all instances, we were still able to identify the individual due to the presence of unique ear tag numbers and tail scars. Moreover, we implanted 6 VHFs, 36 body temperature loggers and 21 heart rate loggers in 28 individuals, and experienced frequent loss of temperature loggers (at least 6 of 23 recaptured beavers) and heart rate loggers (10 of 18 recaptured beavers). No VHFs were lost in 2 recaptured beavers.ConclusionsPossible causes for PIT tag loss (or non-detection) were incorrect implantation, migration of the tag within the body, a foreign body reaction leading to ejection, or malfunctioning of the tag. We speculate that logger loss was related to a foreign body reaction, and that loggers were either rejected through the incision wound or, in the case of temperature loggers, possibly adhered and encapsulated to intestines, and then engulfed by the gastro-intestinal tract and ejected. We discuss animal welfare implications and give recommendations for future studies implanting bio-loggers into wildlife.

Structural damage detection using wireless passive sensing platform based on RFID technology

A wireless and battery-free passive sensing platform is proposed for structural damage detection. The platform is based on the radio-frequency identification (RFID) technology, where a standard RFID transponder device serves as an interface between low-power sensors – used for damage detection – and RFID reading devices. Sensor data are transmitted remotely from this sensing platform to a Personal Computer (PC) that controls the entire system. Energy harvesting is the major novelty of the proposed approach. The magnetic field produced by an antenna of the RFID reading device is used for energy harvesting. The platform supports different types of sensors that can be positioned in remote locations and used for structural damage detection. The sensing capability and the damage detection performance of the proposed system are demonstrated using two simple application examples, that is, vibration measurements in a beam-like structure subjected to the force excitation and temperature measurements in a bearing that supports a rotating shaft. The results illustrate the great potential of the proposed sensing platform for structural health monitoring applications, particularly in remote, difficult-access, or hazardous conditions. Copyright © 2016 John Wiley & Sons, Ltd.

Mobile Transponder Devices in Positioning Systems for Monitoring Earthbound Objects

The construction of an autonomous system for determining the position of objects using mobile communications infrastructure without continuous use of satellite navigations systems is discussed. It is shown that a dual-wavelength optical phasing line for time (phase) synchronization of distributed relay towers can be used to determine the coordinates of objects with an error as small as 10–20 mm and, with simultaneous emission of radio and modulated optical signals, the error can be reduced to 1 mm.

Design and development of a mixed signal prototyping system to achieve very high data rates for contactless applications

Contactless applications like ePassport (electronic passport) demand increased communication speed for higher volumes of exchanged data. Today, those passive applications are working at the carrier frequency of 13.56 MHz, as standardized in ISO/IEC 14443, including data rates up to 848 kbps. However, higher data rates are currently a field of research. For the investigation of very high data rates a mixed signal prototyping system is introduced, based on a new concept of a FPGA-based reader prototyping system. Moreover, an introduction to advanced demodulation methods for contactless transponder devices is given.

Surface acoustic wave modulator

An acoustic wave identification transponder device, having a substrate, an electroacoustic transfer generating an acoustic wave in said substrate and a set of encoding elements disposed in a path of the acoustic wave for modifying the acoustic wave, having elements which reflect portions of the acoustic wave having a component orthogonal to the incident wave. The reflectors may be, for example, trackchangers or reflective arrays compressors (RAC). The wave may be phase-amplitude modulated for increased efficiency expressed in bits per tap. Such phase amplitude modulation is preferably imposed by partial beam width phase delay elements disposed within an acoustic beam path.

Design of passive backscattering RFID devices

The endeavors in realizing ubiquitous chips for ambient intelligence networks increased significantly over the past few years. In particular, the passive radio frequency identification (RFID) technology became a well known synonym for passive transponder devices. The increased attention is not only related to economical advantages, but also to the general technological potential. This article deals with the design of self-sustaining wireless transponders based on the backscattering technology. We explain the general architecture, present important design constraints and emphasize general characteristics of the backscattering radio-frequency (RF) front-end approach. Furthermore, we extend the common linear models by some important nonlinear figures of merit.

PIT Tagging: Simple Technology at Its Best

Abstract Since their first use in the mid-1980s, passive integrated transponder devices (PIT tags) have allowed innovative investigations into numerous biological traits of animals. The tiny, coded markers injected into individual animals allow assessment of growth rates, movement patterns, and survivorship for many species in a manner more reliable than traditional approaches of externally marking animals for identification. PIT tags have also been used to confirm the identity of zoo animals, pets, and protected species that have been illegally removed from the wild. New approaches with PIT tags herald advances in physiology and conservation biology, as well as greater understanding of social interactions among individuals in a population. Despite their current limitations, including high purchase cost, low detection distance, and potential tag loss in some circumstances, PIT tags offer many opportunities to unravel animal mysteries that heretofore could not be addressed effectively.

Identification of individual prawns with implanted microchip transponders

Implanted microchip transponders, of the type widely used in dogs and cats, can be inserted into the body of a prawn, and read in situ. Specimens of Macrobrachium rosenbergii were selected for preliminary studies. Two large males were implanted with transponders 14×2 mm in size, and 20 smaller individuals with 5×2 mm glass dummies as a test for survival rates. The transponders were inserted into the largest portion of the tail musculature, to minimize nerve cord and aortic compression, or inhibition of movement. Virtually all prawns, large and small, successfully tolerated the procedure. Most went through at least three molt cycles without loss of the implants or significantly increased mortality compared to controls. Implants were not affected by the artificial seawater environment nor the body fluids of the prawns. We suggest that the use of transponder devices, especially if they can be made smaller, is a viable technique in prawn aquaculture to identify `selected sires' and founders of new lines of animals with desirable phenotypes.

Microtechnology in telecommunications for spacecraft cost and mass reduction

This paper examines the incorporation of both microelectronics and micromachining (termed microtechnologies) as applied to deep space telecommunication subsystems. Using the Pluto Fast Flyby Pre-Project as a main case study we have reduced the subsystem mass by 50%. This was accomplished via the use of advanced packaging {RF and digital multichip modules (MCMs) and Monolithic Microwave Integrated Circuits (MMICs) for the transponder and advanced GaAs power device technology for solid state power amplifiers}. Micromachined diplexers, filters, and switches using membrane-supported transmission line-technology (MIST-T) provide the potential to reduce subsystem form factor. Another way to reduce mission costs is in the use of both 32 GHz (at Goldstone Deep Space Network {DSN} facility) and 8.4 GHz (at Canberra and Madrid DSN facilities) downlink frequencies. This allows the data to be returned faster, thereby saving both DSN and Mission Operation costs.