We are presenting by this paper on helical antennas which find important applications in communication systems, primarily because of their circular polarization and wide bandwidth. The helical antenna, first introduced by Kraus in 1946, The geometry of larger helical shape type antenna, which is a doubly helical structure, is fully described by five independent parameters, with the including tw...

The design of a novel CPW-fed printed slot-loop antenna with narrowband omnidirectional attributes is proposed. The antenna geometry is selected to reduce slot coupling, thus achieving both a narrow bandwidth and an omnidirectional radiation pattern simultaneously. A gain of 2.1 dBi is accomplished with high radiation efficiency. Very narrow fractional impedance bandwidths as low as 2.9% are re...

A compact microstrip-fed ultra-wideband (UWB) planar monopole antenna with dual band rejected characteristic is presented in this paper. By etching two identical complementary square split ring resonators (CSRRs) in the radiation patch, dual band rejections in the WiMAX and WLAN bands are achieved. The proposed antenna, with the size of 30×34mm2, has been design. And the simulated results show ...

Recently, microwave ultra-wideband (UWB) technology has attracted much attention in high speed wireless communications, imaging and radar applications. Antennas with very wide impedance bandwidth and stable radiations are required for such systems. Among many UWB antennas, planar types are low profile, light weight, low cost and suitable for mobile devices [1]. However, the planar antennas may ...

This paper presents the design of elliptical slot antenna for multiband applications. The suggested antenna covers L-band, WIMAX, WLAN and X band. By placing inverted T-shaped stub and three reverse U-shape stubs, the resonating characteristics of the antenna are observed. The resonating frequencies are 1.95, 4.14, 5.05, 5.89 and 9.15 GHz respectively. The designed antenna shows good return los...

In this paper, a novel compact butterfly shaped printed monopole antenna for ultra-wideband (UWB) applications is presented. The proposed antenna is designed with a standard printed circuit board (PCB) process for suitable integration with other microwave components. The antenna prototype is designed then fabricated and tested experimentally. The calculated impedance bandwidth of the proposed a...

This paper presents a multiband slot antenna with modifying fractal geometry fed by coplanar waveguide (CPW) transmission line. The presented antenna has been designed by modifying an inner fractal patch of the antenna to operate at multiple resonant frequencies, which effectively supports the digital communication system (DCS 1.71–1.88 GHz), worldwide interoperability for microwave access (WiM...

A novel approach for the design of a compact multiband monopole antenna for improving radiation characteristics at higher resonant frequencies is presented. The proposed structure consists of a conventional printed monopole loaded with spiral ring resonators and fed by microstrip. When at higher resonant frequency, the electrical length of the conventional monopole antennas is relatively large ...

A large bandwidth wide-slot antenna, fed by coplanar waveguide (CPW), is proposed. Experimental investigations and detailed simulations are conducted to understand its behavior and to optimize for broadband operation. The impedance bandwidth, determined by 10-dB return loss of the proposed slot antenna using both measurement and simulation, is about 131% (2.8 to 14GHz). In addition to be small ...

In this paper, the effect of antenna sectorization in the reverse link Erlang capacity of a multiclass code-division multiple-access (CDMA) cellular system is studied. Traditionally, it has been considered that the capacity is multiplied by a factor equal to the number of sectors introduced. This is true only in the ideal antenna sectored system. However, due to the nonideal antenna radiation p...