<p>During the work at Gateway Security AB in Motala I began examining available antenna models to get a wider perspective, this have given knowledge of their structure, and an understanding of their function. All my necessary fact is based on my observations and notes of these measurings. </p><p>New antenna models, and available models were examined where measurements at different heights and different distances on the antenna were performed with the help of an oscilloscope and a measure probe, peak – to - peak was brought on the signal. The measurements are presented in a line diagram. </p><p>Further development of simulating tool for antenna designs have been made. Calculations of electromagnetic fields from the antenna take place in the simulation programme Wire-MoM, where the antenna is fed in as a thread structure. I used the data from this programme to present the appearance graphical in 2-dimension in Matlab. Further development represents an improvement of the result presentation management of the simulating tool. </p><p>The results are presented graphical and show the fields at a height of for example 1 meter. Conclusions where taken on the basis of comparison of my results from all the measurements and the graphical image.</p>

During the work at Gateway Security AB in Motala I began examining available antenna models to get a wider perspective, this have given knowledge of their structure, and an understanding of their function. All my necessary fact is based on my observations and notes of these measurings. New antenna models, and available models were examined where measurements at different heights and different distances on the antenna were performed with the help of an oscilloscope and a measure probe, peak – to - peak was brought on the signal. The measurements are presented in a line diagram. Further development of simulating tool for antenna designs have been made. Calculations of electromagnetic fields from the antenna take place in the simulation programme Wire-MoM, where the antenna is fed in as a thread structure. I used the data from this programme to present the appearance graphical in 2-dimension in Matlab. Further development represents an improvement of the result presentation management of the simulating tool. The results are presented graphical and show the fields at a height of for example 1 meter. Conclusions where taken on the basis of comparison of my results from all the measurements and the graphical image.

In this master thesis, compact antenna design aimed towards naval applicationshave been designed, analyzed and evaluated. There is a recentinterest in the development of compact antennas to be used for smallersubmarine models, and with a smaller hull on a submarine, communicationand antenna systems must be adapted and minimized, which limitsantenna design. With two limiting cylindrical volumes with maximumallowed dimensions r = 10 cm, h = 50 cm and r = 5 cm, h = 90 cm,the antennas would operate on the upper to lower V/UHF band, radiatehemispherically and have a high RHCP purity. It was found that the mostappropriate antenna structure for both volumes was QHA design. Afterthe design and analysis process was completed, it was concluded that theshorter antenna design could meet all requirements set while the longerantenna design did not meet all requirements but could still establish agood communication link on the higher frequencies. Antenna prototypesbased on the produced design were constructed and measured and, despiteminor deviations, veried that the results obtained from this thesis werereliable. / I denna mastersuppsatsen har kompakta antenner riktade mot marinaapplikationer designats, analyserats och utvarderats. Det nns ett intressefor utvecklingen av kompakta antenner som ska anvandas for mindreubatsmodeller och med ett mindre skrov pa en ubat maste kommunikationsochantennsystemen anpassas och minimeras darefter, vilket begransarantenndesignen. Med tva begransande cylindriska volymer med maximalttillatna dimensioner r = 10 cm, h = 50 cm samt r = 5 cm,h = 90 cm, skulle antennerna verka pa det ovre till lagre V/UHF-bandet,strala hemisfariskt och ha en hog RHCP-renhet. Det konstaterades attden lampligaste antennstrukturen for bada volymen var QHA-design. Efteratt design- och analysprocessen slutforts drogs slutsatsen att den kortareantenndesignen kunde uppfylla alla krav som stalldes medan den langreantenndesignen inte uppfyllde alla krav men fortfarande kunde upprattaen bra kommunikationslank pa de hogre frekvenserna. Antennprototyperbaserade pa de framtagna designerna konstruerades och mattes och, trotsmindre avvikelser, verierade att de erhallna resultaten fran denna avhandlingvar tillforlitliga.