A frequency agile Vivaldi antenna whose operating frequency band can be switched between two selected bands is proposed in this paper for spectrum monitoring and cognitive radio applications. A RF switch is introduced into the back-slot of a Vivaldi antenna to allow switching of the operational band. The realised gains of the antenna are 10.5 dBi in the low band around 3.1 GHz, and 12 dBi in hi...

Computation of the broadband matching potential of a microstrip antenna requires the wideband lumped equivalent circuit of the antenna. The general topology of the equivalent circuit of rectangular microstrip patch antennas has been used to model the feedpoint impedance of microstrip antennas over a wide frequency band and equivalent circuit parameters are determined using optimization techniqu...

Introduction The microstrip patch antennas are widely used in modern communication system due to low profile, low weight, low cost However, the antennas suffered from narrow bandwidth and low gain.[6 The major need for modern communication devices is to operate at wider band such as to support high speed internet, multimedia communication and similarly many more broadband services, this is achi...

The digital video broadcasting-handheld (DVB-H) service is a new standard for delivering live broadcasting television to handheld terminals and it utilizes UHF bands IV and V (470-862 MHz). However, since the upper limit of the DVB-H frequency band is within a measurable distance of the lower limit of the GSM 900 frequency band, the upper limit will probably be restricted to channel 49 (698 MHz...

Despite their great potential in communication and sensing applications, printed leaky-wave antennas have rarely been reported at mm-wave frequencies. In this paper, tapered operating 80 GHz are designed, fabricated experimentally characterized. While most continuous use subwavelength strips or other comparably small elements, work, the surface impedance is discretized very coarsely using only ...

This paper presents several microstrip patch antennas, for reception at X band. From passive and active single patches to active arrays, design, fabrication, integration and test are addressed.

This paper proposes a method for designing new <em>ultra wide band</em> (UWB) multiple-input multiple-output (MIMO) antenna with two and four elements. First we presented an ultra-wide band studied these performances. Then, the application of metamaterials to design MIMO antennas miniaturization performance antennas, in order guarantee proper functioning system much reduced separati...