In this paper, CPW-Fed ultra wideband (UWB) planar monopole antenna (PMA) loaded by double elliptical split ring resonators (ESRRs) for double band-notch characteristics is introduced and examined. Two different ESRRs with different dimensions are printed in the antenna backside to notch two different frequencies. The ESRRs are also rotated and the corresponding return loss effect is examined. Different notch frequencies can be obtained by varying the ESRRs, dimensions. Two single SRRs are used to notch two frequencies instead of using dual SRR pairs. Two notch frequencies at 5.2 GHz and 6.9 GHz has been obtained to notch WLAN and C-band wireless applications, respectively. A directive radiation pattern in E-plane and omnidirectional radiation patterns in the H-plane could be observed. Also the gain is suppressed in the notch frequencies. The group delay is nearly stable in the UWB frequency range, except at the notch frequencies, which is distorted sharply. So, the proposed antenna is a good candidate for the modern UWB systems. Finite element method FEM and finite integration technique FIT are used to simulate the proposed structures through the usage of Ansys HFSS and CST MWS. Very good agreement between both results has been obtained.

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The scope of this paper is to examine the effect of changing the structure of split ring resonator SRR from circular to an elliptical shape. The theoretical analysis of circular SRR (CSRR) is first examined and its results are compared with the simulated ones. Comparison between both configurations is also introduced. The new elliptical SRR (ESRR) can be adapted to operate in a multi-range of frequencies. The effect of gap position in ESRR resonant is also examined. When both gaps are moved but still aligned, the resonant frequency still the same. But when single gap is moved only the resonant frequency in changed to reach its maximum value when both gaps are in the same position. Frequency tunability can be offered by loading only a single varactor diode between the ESRR's metallic rings. The resonant frequency of the ESRR can be controlled by varying the capacitance of the varactor diode. Finite Element Method FEM is used to simulate the proposed structures using Ansys HFSS. A prototype of band notched coplanar waveguide filter loaded with single reconfigurable ESRR is fabricated and measured. A 0.5 pF single capacitor element is used instead of using varactor diode and the measured S 21 is compared with the simulated results. Very good agreement has been obtained between them. A 5.6 GHz and 5.4 GHz notch frequencies in the filter operating frequencies are obtained using ESRR without and with varactor loading, which covers WLAN band.

Health and safety concerns have grown in recent years due to the increasing frequency bands and the demand for wireless communication apparatus. Electromagnetic (EM) radiation breakthrough from Radio frequency (RF) into the human head is an issue that needs to be addressed. Radiation from RF sources can cause serious biological hazards inside the human body. This study measures the average Specific Absorption Rate in a 7-year-old child's head tissues using the ANSYS HFSS software and varying the distance from the source to the antenna in order to address these issues. SAR levels of phones sold should be below certain standard limits. We have used an internal antenna of a mobile phone It's a planar inverted F-antenna (PIFA) with a connected feeding structure.

Employing electromagnetic waves in mobile communication networks has increased the level of human exposure to electromagnetic fields that may result in concerns about health hazards associated involves the soaking up of cellular phone electromagnetic energy. The human body is penetrated by the electromagnetic fields that emit from a cell phone. The specific absorption rate (SAR) that is generated in the human head and body layers usually expresses the thermal effect on human tissue. The main objective of this paper is to investigate the thermal effects of the electromagnetic field induced inside the human head and body through the construction of a simplified model for both. The RF-source and human body models are built by using the ANSYS high-frequency structural simulator (HFSS). A planar inverted-F antenna (PIFA) will use to assign SAR values to different body tissues for the fourth generation (4G) of mobile phone communication at an operational frequency of 2.6 GHz and power radiated of 125 mW. The model is simulated and analyzed to evaluate the SAR induced at different human tissues depending on the source-to-antenna distance and its generated values must not exceed the safe limits for harmful thermal effects.