Dehmas, Mokrane2020-12-162020-12-162020https://dspace.univ-boumerdes.dz/handle/123456789/593689 p. : ill. ; 30 cmIn this thesis, three compact microstrip antennas based on the defected microstrip (DMS) and the shorting post insertion techniques are developed. The first is a single-band operating in the radar 3 GHz frequency. It achieves a miniaturization ratio of around 77 % compared to a conventional rectangular structure. The second is a dual-band monopole covering UHF radio frequency identification bands. A size reduction of nearly 44 % is achieved compared to a reported structure. The third is a multi-band antenna operating in six frequency bands suitable for different applications involving commercial ones. A size reduction of nearly 60 % with respect to the original antenna has been obtained. Prototypes of the proposed antennas have been fabricated and their input reflection coefficientsfrSize reductionDMSShorting postThesis