in recent years reflectarray antennas have received considerable attention due to their unique capabilities. however, due to their large size, analyzing the performance of these antennas using traditional full wave finite-difference and finite-element techniques requires considerable computational resources. in this paper, we present an efficient method to accurately analyze these class of ante...

A new shaped circularly polarized dielectric resonator antenna (CP DRA) is studied with branch-line coupler and log-periodic balun for the GPS application. Since the coupler and balun are located under the DRA, it does not increase the footprint of the antenna, as a result the system is very compact. Two configurations are considered in this paper. In the first configuration, an external 50Ω lo...

Tone Reservation (TR) is one of the well-known methods for PAPR reduction of Orthogonal Frequency Division Multiplexing (OFDM) systems. In this method some sub-carriers are reserved for PAPR reduction and the symbols in these sub-carriers are selected such that the PAPR of the OFDM frame is minimized. In this paper, the iterative algorithm introduced earlier for TR method in single antenna OFDM...

recently a new structure called groove gap waveguide (GGW) is ‎introduced to implement low loss microwave component devices ‎especially for millimeter wave applications. This paper presents a ‎new type of H-plane horn antenna making use of this new technology ‎in which backward radiation is significantly suppressed by ‎introducing a high impedance surface at the antenna aperture. The ‎high impe...

A newly designed printed slot antenna is presented that incorporates variable two band-notched functions for ultra-wideband (UWB) applications. The two band notches of this coplanar waveguide (CPW) fed antenna are achieved by an M-shaped slot (MSS) embedded in the radiating element and a C-shaped strip (CSS) close to ground plane, therefore two very narrow rejected properties in the wireless lo...

This paper presents a new approach for design of the log-periodic dipole array antenna (LPDA) based on using of different design parameters in the LPDA elements to control the antenna behavior. In the proposed procedure, the design parameters can control the value of forward gain over the operating frequency range, and also adjust the gain flatness. Furthermore, this design procedure can decrea...

An analytical technique is proposed for estimation of the radiation pattern of inverted-F antenna (IFA) which is mounted on the side wall of a long cylinder. The method can be applied to describe the IFA radiation in a lot of practical cases. It is indicated that this radiation pattern is a combination of radiation patterns of a horizontal and a vertical small radiator, near the cylinder with a...