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3 Uppsatser om 2-cc coupler - Sida 1 av 1

Analys och förbättringsförslag för riktkopplardesign

Ericsson develops a new stripline directional coupler. Its design is described in appendix B and differs from the directional couplers Ericsson uses in current products. The new directional coupler will be used for transmission power measurement in future UMTS 3G base stations.The most important parts of directional coupler theory are presented. It is necessary to study this theory to understand how the coupler works and how it should be designed to get good performance.Optimal directional coupler termination component values to get high directivity and broad directivity bandwidth have been investigated.The trim screws trim ranges have been studied.A simple analysis of serial production performance when termination component tolerances are taken into consideration has been done.The resistance components reactive (inductive/capacitive) characteristics at 2.14 GHz have been analyzed.The directivity performance limitations of the directional coupler, when Ericsson?s band pass filter is connected, are investigated.Design changes leading to better performance are proposed.

Utveckling av snabbfäste och verktyg för byte av sågklinga

This thesis is based upon the work done at Westinghouse electric company (WEC)inVästerås during the spring semester of 2015 and describes the development of a quickcoupler with associated blade changing tool. These are meant to be used togetherwith a sawing tool that the company uses for the dismantling of nuclear reactors,which is performed under water.The aim of the thesis was to develop a complete manufacturing documentation withdrawings and related CAD models which Westinghouse later can use to manufacturethe tool and the quick coupler. It was also included in the assignment to, if necessary,modify parts of the saw tool to adapt these to the intended blade changing tool.A number of visits to the company's workshop was made during the time to study thesaw that the thesis is based upon. The purpose of these visits was to get a better ideaof the dimensions, construction and the field of use of the saw. On three of thoseoccasions various engineers and consultants accompanied us to discuss possibleproblems with different ideas.This was interspersed with information in the form of literature studies on quickcouplers to create a clearer picture of the nature of the task.When enough information had been gathered a functional analysis was made to dividethe main problem into subthis phase the idea and concept generating process took place.The methods used for this was mainly brain writing and brainstorming.

In-situ audiometri ? Vägen mot rätt förstärkning?

This study investigated whether in-situ audiometry, delivered via hearing aids, is a better option as a basis forprescribing hearing aid amplification, compared to conventional audiometry. By examining the real ear insertgain (REIG) in 29 ears (18 subjects), that had been fitted with a hearing aid programmed using both conventionalaudiometry and in-situ audiometry, the study looked at whether in-situ audiometry based prescription is closer tothe NAL NL1's fitting target than audiogram based prescription. The hearing aid Siemens Pure 7mi with speakerunit M was used on all participants. The results showed how in-situ audiometry based gain at certain frequenciesis more consistent with the target curve, especially at 1000, 1500, 2000 and 4000 Hz. It was not establishedwhether the findings of the study were statistically significant.