A Novel Smiley Fractal Antenna (SFA) Design and Development for UWB Wireless Applications

              The objective of the project is design and implementation of Smiley Fractal Antenna for Ultra Wideband (UWB) applications. Fractal antennas are simple, light weight and compact in size. The proposed antenna is employed with N-notch feed and modified ground plane, and is of compact size, fabricated on an FR-4 substrate with . The CPW feed used in the proposed system helps the antenna to achieve the bandwidth in the ration of 6:1.  The radiation pattern of the proposed antenna is omnidirectional with a maximum gain of 4.83 dB and efficiency of 93.55% is obtained.  For the design and analysis, Ansys HFSS software is being used.   The simulated results obtained show that the proposed antenna is a suitable candidate for multiband and wideband applications.

Multiband Micro-strip Antenna For Long Term Evolution MIMO System

Nowadays, there are more and more interests in research on multi-input and multi-output (MIMO) systems in the wireless communication. Since it has the ability to increase the capacity of channel using the spatial properties of multipath, it is necessary to have a number of uncorrelated antennas at each end of the communication link. So it seems to be very essential to design adequate antenna due to use in MIMO systems. As revealed in many literatures, both of nonprinted MIMO antennas such as planar-inverted F antennas (PIFAs) and printed MIMO antennas are proposed. However, among the antennas which are used for MIMO application, printed antennas are more appropriate due to their low cost, easy fabrication, and their capability of easily being integrated to small terminal devices

Compact Wide-Beam Circularly-Polarized micro strip Antenna with a Parasitic Ring for CNSS Application

ABSTRACT:

A compact single-feed circularly-polarized (CP) wide beam micro strip antenna is proposed for CNSS application. The antenna is designed with a double-layer structure, comprising a circular patch with two rectangular stubs along the diameter direction and a parasitic ring right above it. The resonance frequency and the CP characteristics are mainly controlled by the circular patch and the rectangular stubs, respectively. The vertical HPBW (half power beam width) could be widened by the parasitic ring. Experimental results show that the measured vertical HPBW is approximately 140° and the measured out-of-roundness for the horizontal radiation pattern is only 1.1 dB. Besides, it could maintain good low-profile characteristics

COMPACT ULTRA-WIDE-BAND ANTENNA WITH BAND REJECTION CHARACTERISTICS

With the development of wireless communications, ultra-wide-band (UWB) technology has been regarded as one of the most promising technologies in the wireless world because of their attractive features, including high-speed data rate, extremely low spectral power density, high-precision ranging, low complexity and low cost, robustness to multi-path fading and very low interference. These applications make the Federal Communications Commission to dedicate 7.5 GHz of the spectrum from 3.1 to 10.6 GHz for UWB radio applications. One of the key issues in the UWB communications is the design of a compact antenna while providing wideband characteristics over the whole operating band. Owing to the rapid development of such an UWB system, a great deal of attention is being given for the designing of the UWB antennas. This is quite challenging in satisfying the requirement of the UWB, such as ultra-wide impedance bandwidth, omnidirectional radiation pattern, constant gain, high radiation efficiency, constant group delay, low profile and easy manufacturing.

Multiband Reconfigurable E shaped Micro-strip Antenna

Reconfigurable antennas are being given much focus for their versatility, compact size, low cost and high performance. Reconfigurable antennas radiate more than one pattern at different frequencies and with various polarizations providing more flexibility to antenna designers. Due to the additional degree of freedom, there is a large potential for increased system performance. The ability to switch between various systems has recently attracted special attention to reconfigurable antennas. This class of radiator can change its operating frequency, polarization or radiation pattern with the use of GaAS FET, PIN diodes and RF MEMS

COMPACT ULTRA-WIDE-BAND MONOPOLE ANTENNA WITH BAND REJECTION CHARACTERISTICS

ABSTRACT

With the development of wireless communications, ultra-wide-band (UWB) technology has been regarded as one of the most promising technologies in the wireless world because of their attractive features, including high-speed data rate, extremely low spectral power density, high-precision ranging, low complexity and low cost, robustness to multi-path fading and very low interference. These applications make the Federal Communications Commission to dedicate 7.5 GHz of the spectrum from 3.1 to 10.6 GHz for UWB radio applications. One of the key issues in the UWB communications is the design of a compact antenna while providing wideband characteristics over the whole operating band. Owing to the rapid development of such an UWB system, a great deal of attention is being given for the designing of the UWB antennas. This is quite challenging in satisfying the requirement of the UWB, such as ultra-wide impedance bandwidth, omnidirectional radiation pattern, constant gain, high radiation efficiency, constant group delay, low profile and easy manufacturing.

Proposed System:

            To design of such antennas for UWB communication also needs a band rejection filter to avoid interference with existing wireless networks with standards such as IEEE 802.11a in USA (5.15–5.35 GHz, 5.725–5.825 GHz), (3.4–3.6 GHz) for worldwide interoperability for microwave access (WiMAX) and HIPERLAN/2 in Europe (5.15–5.35 GHz, 5.470–5.725 GHz); therefore the UWB transmitters cannot cause any electromagnetic interference on other communication systems nearby.

MINIATURIZATION OF MICROSTRIP ANTENNA

ABSTRACT

In recent years, wireless smart systems have rapidly emerged in areas such as healthcare and activity monitoring with applications in outpatient monitoring and the provision of in-home lifelines for the elderly. Wireless sensor motes operating in the 433 MHz industrial scientific and medical (ISM) band are a popular choice for low data rate applications and provide a good communication range due to reduced body absorption when compared to higher frequencies. Small and lightweight sensor realisations are key constraints for unobtrusive monitoring and an example of a 433 MHz sensor device is presented in measuring 25 mm2 in size excluding the antenna. A λ0/4 resonant antenna at 433 MHz would require dimensions of ∼170 mm excluding a ground plane.

Proposed System:

To designs a compact, planar antenna operating at 433 MHz for wireless smart systems printed on a low-cost FR4 material. Significant size reduction can be achieved using a square-spiral section and rectangular patch element. For the intended application, the goal is to realise a wrist-worn sensor with an area of 5 0× 30 mm².Sensor and radio transceiver electronics can be accommodated above the ground plane.