This thesis presents low-profile and small antennas for horizontal and circular polarization (CP) radiations. Installing small-sized antenna is one of the main requirements in wireless devices for such as various mobile telecommunications, RFID systems and Wireless sensor network systems (WSNs). In this thesis, the proposed antennas consist of three structures which radiate linear or CP in parallel to the ground plane or their elements. These antennas are based on a split ring antenna (SRA).