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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Integrating a Limiter/Filter/Amplifier into a Conformal Wraparound GPS/TM Antenna Substrate

Ryken, Marv, Davis, Rick, Kujiraoka, Scott 10 1900 (has links)
International Telemetering Conference Proceedings / October 18-21, 2004 / Town & Country Resort, San Diego, California / Missile instrumentation systems designers are constantly striving to achieve better performance out of their systems. Optimizing the antenna coverage and decreasing the noise figure are constantly strived for in order to improve system performance. At the same time, weapon systems are becoming smaller with the resulting reduced area for instrumentation. One way to achieve a lower system noise figure is to have the limiter, filter, and amplifier (LFA) located as close to the antenna as possible. This can be achieved by integrating the LFA into the substrate of a conformal wraparound antenna. Not only does this decrease the system noise, but it also saves space in an already crowded missile instrumentation section. This paper details the latest efforts in accomplishing this integration.
2

PHASE CENTER MEASUREMENTS FOR A WRAP-AROUND GPS ANTENNA

Meyer, Steven J., Kujiraoka, Scott R. 10 1900 (has links)
International Telemetering Conference Proceedings / October 23-26, 2000 / Town & Country Hotel and Conference Center, San Diego, California / Global Positioning System (GPS) technology is being used as a sensor in telemetry systems to provide time, space and position information (TSPI) as well as end game or vector scoring. The accuracy of these measurements depends on precisely locating the phase center of the GPS antenna. A procedure has not currently been addressed by anyone to measure the phase center of a conformal wrap-around GPS antenna. This paper will discuss some techniques on determining the antenna phase center.
3

DESIGN OF A GPS/TELEMETRY ANTENNA FOR SMALL DIAMETER PROJECTILES

Ryken, Marv, Davis, Rick, Kujiraoka, Scott R. 10 1900 (has links)
International Telemetering Conference Proceedings / October 23-26, 2000 / Town & Country Hotel and Conference Center, San Diego, California / In the past, airplanes, target drones, pods, and large missiles have been instrumented with telemetry, flight termination and beacon tracking antennas to assess performance. With the emerging use of the Global Positioning System (GPS) for tracking purposes, GPS is also included as part of the instrumentation package. This paper addresses the design of a conformal wraparound antenna system to cover the telemetry and GPS L1 frequencies for a small (2.75 inch) diameter airborne projectile. A filter is also integrated into the antenna system to isolate the transmitted telemetry signal from the received GPS signal. This integration is necessary due to the lack of space in the small diameter projectile. Performance characteristics of the prototype antenna system are also presented.
4

PHASE CENTER PROBLEMS WITH WRAP-AROUND ANTENNAS

Meyer, Steven J., Kujiraoka, Scott R. 10 1900 (has links)
International Telemetering Conference Proceedings / October 21, 2002 / Town & Country Hotel and Conference Center, San Diego, California / The Joint Advanced Missile Instrumentation (JAMI) program is integrating Global Positioning System (GPS) technology into missile telemetry systems. The weakest link appears to be the GPS antenna. The antenna on a missile is required to be flush mounted for aerodynamic reasons. Due to the missile’s tendency to roll, the antenna needs to be a multi-element omnidirectional antenna array. Therefore an antenna used on missiles is a wrap-around antenna since it will meet the flush mount and rolling requirements by giving omnidirectional coverage. JAMI has used readily available techniques for designing wrap-around telemetry antennas to develop a GPS wrap-around antenna and has discovered a major problem. The Phase Center of a wrap-around antenna tends to be a surface, not a point, and not necessarily at the centerline of the missile body. GPS measurements have been conducted to determine the Phase Center of the antenna. When the Phase Center is large, the GPS receiver perceives it as multipath and integer ambiguities cannot be resolved. This paper addresses the problems that have been uncovered and outlines the steps that are planned to resolve them.
5

New Developments in Integrated Airborne Antennas

Ryken, Marv 10 1900 (has links)
ITC/USA 2011 Conference Proceedings / The Forty-Seventh Annual International Telemetering Conference and Technical Exhibition / October 24-27, 2011 / Bally's Las Vegas, Las Vegas, Nevada / New developments in miniaturized integrated film bulk acoustic resonator (FBAR) filters and low noise amplifiers have resulted in the possibility of extremely small integrated antenna, filter, and low noise amplifier subsystems for use in airborne telemetry (TM) systems. This paper gives examples of a new development in airborne GPS antennas using an integrated band pass FBAR filter and low noise amplifier. Data is also included on the example antenna in a GPS/TM system.
6

Contemporary Arts Center: A Time of Transition

Naring, Samantha 01 May 2016 (has links)
The following report documents my 480-hour internship from August 17th, 2015 to January 29th, 2016 in the Education and Public Programs Department at the Contemporary Arts Center (CAC). I worked closely with the Marketing and Visual Art Departments. I chose the organization to experience an environment that commits itself to presenting high quality performing and visual arts. This paper assesses the CAC’s history, present day status, and future outlook. It also offers suggestions on how certain aspects can be improved in order to extend the organization’s longevity. Over the course of five months I observed strengths, weaknesses, opportunities and threats to the organization. Additionally, using knowledge gained from my Arts Administration classes and personal observations, this paper offers predictions as to the organization’s future.
7

Device-device communication and multihop transmission for future cellular networks

Amate, Ahmed Mohammed January 2015 (has links)
The next generation wireless networks i.e. 5G aim to provide multi-Gbps data traffic, in order to satisfy the increasing demand for high-definition video, among other high data rate services, as well as the exponential growth in mobile subscribers. To achieve this dramatic increase in data rates, current research is focused on improving the capacity of current 4G network standards, based on Long Term Evolution (LTE), before radical changes are exploited which could include acquiring additional/new spectrum. The LTE network has a reuse factor of one; hence neighbouring cells/sectors use the same spectrum, therefore making the cell edge users vulnerable to inter-cell interference. In addition, wireless transmission is commonly hindered by fading and pathloss. In this direction, this thesis focuses on improving the performance of cell edge users in LTE and LTE-Advanced (LTE-A) networks by initially implementing a new Coordinated Multi-Point (CoMP) algorithm to mitigate cell edge user interference. Subsequently Device-to-Device (D2D) communication is investigated as the enabling technology for maximising Resource Block (RB) utilisation in current 4G and emerging 5G networks. It is demonstrated that the application, as an extension to the above, of novel power control algorithms, to reduce the required D2D TX power, and multihop transmission for relaying D2D traffic, can further enhance network performance. To be able to develop the aforementioned technologies and evaluate the performance of new algorithms in emerging network scenarios, a beyond-the-state-of-the-art LTE system-level simulator (SLS) was implemented. The new simulator includes Multiple-Input Multiple-Output (MIMO) antenna functionalities, comprehensive channel models (such as Wireless World initiative New Radio II i.e. WINNER II) and adaptive modulation and coding schemes to accurately emulate the LTE and LTE-A network standards. Additionally, a novel interference modelling scheme using the 'wrap around' technique was proposed and implemented that maintained the topology of flat surfaced maps, allowing for use with cell planning tools while obtaining accurate and timely results in the SLS compared to the few existing platforms. For the proposed CoMP algorithm, the adaptive beamforming technique was employed to reduce interference on the cell edge UEs by applying Coordinated Scheduling (CoSH) between cooperating cells. Simulation results show up to 2-fold improvement in terms of throughput, and also shows SINR gain for the cell edge UEs in the cooperating cells. Furthermore, D2D communication underlaying the LTE network (and future generation of wireless networks) was investigated. The technology exploits the proximity of users in a network to achieve higher data rates with maximum RB utilisation (as the technology reuses the cellular RB simultaneously), while taking some load off the Evolved Node B (eNB) i.e. by direct communication between User Equipment (UE). Simulation results show that the proximity and transmission power of D2D transmission yields high performance gains for a D2D receiver, which was demonstrated to be better than that of cellular UEs with better channel conditions or in close proximity to the eNB in the network. The impact of interference from the simultaneous transmission however impedes the achievable data rates of cellular UEs in the network, especially at the cell edge. Thus, a power control algorithm was proposed to mitigate the impact of interference in the hybrid network (network consisting of both cellular and D2D UEs). It was implemented by setting a minimum SINR threshold so that the cellular UEs achieve a minimum performance, and equally a maximum SINR threshold to establish fairness for the D2D transmission as well. Simulation results show an increase in the cell edge throughput and notable improvement in the overall SINR distribution of UEs in the hybrid network. Additionally, multihop transmission for D2D UEs was investigated in the hybrid network: traditionally, the scheme is implemented to relay cellular traffic in a homogenous network. Contrary to most current studies where D2D UEs are employed to relay cellular traffic, the use of idle nodes to relay D2D traffic was implemented uniquely in this thesis. Simulation results show improvement in D2D receiver throughput with multihop transmission, which was significantly better than that of the same UEs performance with equivalent distance between the D2D pair when using single hop transmission.
8

Effektivisering av paketeringslinje

Lindström, Konni, Krantz, Sebastian January 2017 (has links)
Detta examensarbete har gjorts direkt mot båda författarnas inriktning inommaskiningenjörsprogrammet. Inriktningen är produktionsutveckling ochexamensarbetet har inneburit utveckling av ett paketeringssystem från grundenbaserat på ett enklare befintligt system. Det nuvarande systemet som finns påKvibilles mejeri har föråldrad utrustning och dålig kapacitet, vilket mejeriet villeförbättra. Projektet har gett författarna möjlighet att testa och utvidga sina kunskaperinom sitt utbildningsområde. Det som utförts i projektet har inneburit mycket informationssökande, teorin bakominnefattar bl.a. produktionssystem, arbetsplatsergonomi, modeller förproduktionsutveckling, direktiv, regler och utvärderingsmetoder samt givetvis dataom de maskiner och den utrustning som varit intressant för projektet. Det harförutom informationssökning inneburit kontakt med en rad olika maskinleverantörerför att få information och priser. Metodiken som används bestämdes under projektets förstudie, metoden är utveckladav Bellgran & Säfsten (2005) och är en ren produktionsutvecklingsmetod. Metodenhar följts till de delar som varit intressanta och vissa delar såsom driftsättning harförbisetts då resultatet av projektet inte realiserats. Metoden innebar bl.a. en studie avnuvarande och liknande produktionssystem samt intervjuer med dess operatörer. Projektets gång ledde till ett antal koncept för en helt ny paketeringslinje som inte harmånga likheter med den nuvarande linjen och dess arbetssätt. Författarna är mycketnöjda med det resulterande slutgiltiga konceptet och de fördelar konceptet innebärsom är av både teknisk och ekonomisk karaktär. Huvudresultaten inkluderar 50%ökad kapacitet och minskade manuella tunga moment som lett till minskat behov avoperatörer. / This thesis is in line with the two author’s orientation within the mechanicalengineering program. The orientation is production development and the project hasbeen to develop a new packaging line based on a simple existing one. The existingsystem is located in a dairy plant and have old equipment and low capacity which theplant want to improve. The project has given the authors opportunity to use andwiden their knowledge within their area of education.The project includes a lot of research, the theory behind the project is amongst otherthings; production systems, evaluation systems, work ergonomics, models forproduction development, directives, rules and data for the machines and equipmentneeded for the project. Contact has been made with several machine suppliers to findinformation and to get prices. The method used was decided during the projects background study, the method isdeveloped by Bellgran & Säften (2005) and is a method designed purely forproduction development. Only applicable parts of the method has been used whichmeans that some parts where left out such as the part for deployment since theproject won’t be realized as of now. The method included a study of the currentsystem and similar production systems as well as interviews with the staff. This project has led to a number of concepts for a new production system that worksvery different compared to the old system. The authors are very pleased with theresulting new final concept and the improvements it lead to which is technical andeconomical. The main results is 50% improved capacity and reduced heavy manualtasks which has resulted in less need of line operators.

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