Thesis (M. S.)--Florida State University, 2005. / Advisor: Dr. Mark H. Weatherspoon, Florida State University, College of Engineering, Dept. of Electrical and Computer Engineering. Title and description from dissertation home page (viewed Sept. 19, 2005). Document formatted into pages; contains viii, 70 pages. Includes bibliographical references.

Thesis (MScEng)--Stellenbosch University, 2012. / ENGLISH ABSTRACT: This thesis describes the design and construction of a two-element digital correlation interferometer operating at 1.42 GHz. This instrument consists of two 92cm off set-parabolic reflectors arranged in an east-west baseline, with a maximum length of 24m. The reflectors are out-fi tted with helical beam antennas as primary feeds, and are further equipped with low-noise front-ends. A wideband dual-conversion superheterodyne receiver processes the astronomical signals before digitisation. The receiver is implemented as far as possible using a ffordable off -the-shelf technologies. The cross-correlation between the two antenna signals is measured using a 256MHz bandwidth digital FX correlator, and is implemented on a Reconfi gurable Open Architecture for Computing Hardware (ROACH) board. The preliminary observations made with this interferometer, suggests that it is possible to detect the sun, and some other much weaker sources such as Taurus A. The design of an interferometer in general is presented, from the formulation of the underlying instrumental requirements, to making meridian drift scan observations. The interferometer developed may serve as a demonstrator for other engineering students to gain a working knowledge of radio interferometry, which should prove invaluable when addressing the challenges the Square Kilometre Array (SKA) is faced with. / AFRIKAANSE OPSOMMING: In hierdie tesis word die ontwerp en konstruksie van 'n twee-element digitale korrelasie interferometer wat by 1.42 GHz ontvang beskryf. Die instrument bestaan uit twee 92 cm afsetparaboliese re ektorantennas met 'n oos-wes basislyn, met maksimum lengte 24 m. Heliese antennas word gebruik as primêre voer vir die reflektors, en verder maak die voorent gebruik van laeruis versterkers . Die wyeband superheterodineontvanger verwerk die astronomiese seine in twee stappe voordat dit digitaliseer word. Bekostigbare kommersiëele komponente word gebruik in die vervaardiging van die ontvanger. Die kruiskorrelasie tussen die twee antenna seine word digitaal gemeet deur 'n FX korreleerder met 'n 256MHz bandwydte op 'n ROACH bord. Die resultate toon aan dat dit moontlik is om die son waar te neem, sowel as sommige ander swakker bronne, soos Taurus A. Al die kwessies insluitende die instrumentale vereistes betrokke by die ontwerp van 'n interferometer word bespreek. Verder word die gebruik van interferometers om meridiaan meetings te doen bespreek. Die interferometer dien as 'n praktiese demonstrasie van radio interferometrie vir ingenieurstudente. Hierdie demonstrasie is voordelig vir studente om die uitdagings van die SKA te bestudeer.

This work deals with design, simulation and realisation of a receiving systém of an S-band front end for satellite communication. The first part of the project is designed the low noise amplifier (LNA) with high associated gain. The basic point of the design is choice of the active device. In the present time are available the ultra low noise transistors based on the GaAs with high mobility electron. The two-stage LNA has been designed with Agilent ATF-55143. It is pseudomorphic HEMTs ,which work in an enhancement mode.These transistor do not require a negative bias voltage and have extremely good typical noise figure. The design includes an interdigital tuned band pass filter between stages. The second part of the project is search another way design circuit. There are designed two LNA with paralel coupled line filter. The first has been applied on a PTFE substrate Duroid 5880 with relative permitivity 2,2 and tg d = 0,009. The substrate FR-4 (r = 4.34) with the thickness 0.06” was used for the realization.