Informatics Publishing Limited

A. Sudhakar ¹, M. Satyanarayana ², M. Sunil Prakash ², Sudhir Kumar Sharma ³

Affiliations
1 ECE Department, GMR Institute of Technology, Rajam - 532127, Andhra Pradesh, IN
2 ECE Department, MVGR College of Engineering, Vizianagaram - 535005, Andhra Pradesh, IN
3 ECE Department, Jaipur National University, Jaipur - 302017, Rajasthan, IN

Abstract

In this paper, a printed Ultra Wide Band (UWB) antenna of small size with variable frequency band-notched properties is presented. Finite element based HFSS software is used to simulate the proposed antenna and then fabricated. The parameters of fabricated antenna are measured with E5071C vector network analyser. The measured and simulated results are in good agreement. A stepped radiating patch is printed on one side and stepped ground plane on the other side of FR- 4 substrate to increase the bandwidth from 4.3 GHz to 11.28 GHz. Introduction of two protruding strips having a length of λ/2 in rectangular slot results to get frequency notch characteristics in WLAN (5.15–5.85 GHz) band. The effects of length and thickness of individual protruding strips on band notch characteristics are examined. By varying either the length or the thickness of protruding strips incorporated in the rectangular slot, we can control the band notch frequency and its band width. The presented antenna has a small size of 12 x 18 x 1.6 mm3and reveals a steady gain throughout the UWB except at notched band of 4.9 GHz 6.1 GHz. The radiation pattern in the E-plane and H-plane is like a figure of eight.

Keywords

Antenna, Frequency Notch, Protruding Strips, Rectangular Slot, UWB

Full Text

   

A. Sudhakar ¹, M. Satyanarayana ², M. Sunil Prakash ², Sudhir Kumar Sharma ³

Affiliations
1 ECE Department, GMR Institute of Technology, Rajam - 532127, Andhra Pradesh, IN
2 ECE Department, MVGR College of Engineering, Vizianagaram - 535005, Andhra Pradesh, IN
3 ECE Department, Jaipur National University, Jaipur - 302017, Rajasthan, IN

Abstract

Objective: This paper suggests a small microstrip antenna with WLAN frequency rejection properties to avoid interference between UWB systems. Methods/Analysis: At initial stage the dimension of suggested antenna are calculated by the available formulae in the literature and then is simulated by HFSS which is based on FEM to get optimized dimensions. The features of the manufactured antenna are checked with E5071C vector network analyser and compared with software generated results for validation. Findings: This antenna comprises of “S” shaped slot etched on the patch of FR4 substrate on front side and ground is having steps on rear. Top and bottom of the substrate is covered with a dielectric material (Teflon) of different dimensions. By proper selection of dimensions of patch and positions of slot on the radiating patch, the broadband property and frequency notching is achieved. The bandwidth of the suggested antenna is found to be 88.7% with operating frequency band from 4.26 GHz to 11.06 GHz and frequency notching range 4.85-5.97 GHz is obtained. It is shown that the shifting of rejected frequency can be observed by altering the size and type of dielectric resonant material. The suggested antenna has a small size of 12 x 18 x 6.6 mm3 and discloses a maximum gain of 4.99 dB. Applications: The suggested antenna can be used to avoid the intervention between UWB systems and other existing systems in the operating frequency range 5-6 GHz.

Keywords

Dielectric Resonant Material, Frequency Notch, Microstrip Feed, Patch Antenna, “S” Shaped Slot.

Full Text

   

D. Prabhakar ¹, P. Mallikarjuna Rao ², M. Satyanarayana ³

Affiliations
1 Department of Electronics and Communication Engineering, DVR and Dr. HS MIC College of Technology, Kanchikacherla –521180, Andhra Pradesh, IN
2 Department of Electronics and Communication Engineering, Andhra University College of Engineering (AUCE), Visakhapatnam – 530003, Andhra Pradesh, IN
3 Department of Electronics and Communication Engineering, Maharaj Vijayaram Gajapathi Raj (MVGR) College of Engineering (Autonomous), Vizianagaram – 535005, Andhra Pradesh, IN

Abstract

Objective: This research paper focuses on the simulated design and its analysis of 2 element microstrip patch antenna arrays with Quarter wave transformer feed and mitered bend feed network that is widely used in ISM frequency bands in the field of wireless communications. Methods: Various types of microstrip array antennas using Quarter wave transformer feed and with miter bend feeds are designed using HFSS 13.0 and fabricated by photolithography technique using FR-4 substrate, which is tested using VNA E5071C. Findings: The optimum performance of the feeding system is based on various antenna parameters. Here 1X2 array antennas are designed. Miter bends are used for better impedance matching. Usage of miter bends declines the reflection coefficient. There is improvement in gain by using miter bend feed network. Applications: Good impedance matching, optimum reflection coefficient and high gain are achieved by metered bends. The obtained results show that the designed antenna is an apt tool for communications.

Keywords

Corporate Feed, HFSS, Microstrip Antenna, Mitered-Bend Feed, Quarter-Wave Feed Transformer, Reflection Coefficient, WLAN

Full Text

   

B. Ramana Babu ¹, A. Chandra Sekhar ², M. Satyanarayana ³, R. M. Preethi ⁴

Affiliations
1 Department of Computer Science and Engineering, Sanketika Institute of Technology and Management, Visakhapatnam, Andhra Pradesh, IN
2 Department of Computer Science and Engineering, Avanthi Institute of Engineering & Technology, KOTABHOGAPURAM, Andhra Pradesh 535006, IN
3 Department of Computer Science and Engineering, Andhra University College of Engineering (A), Visakhapatnam, IN
4 Department of Computer Science and Engineering, AVANTHI Institute of Engineering & Technology, NARSIPATNAM, Andhra Pradesh, IN

Abstract

Objectives: Requests for ADMINSHIP (RFA) within Wikipedia are primarily focused on the impact of the relationship between ADMINSHIP candidates and voters on RFA success. Very few studies, however, have investigated how candidates’ contributions may predict their success in the RFA process.

Methods/Statistical Analysis: In this examination, we look at the effect of substance and social commitments and in addition add up to commitments made by ADMINSHIP hopefuls on the group's general choice in the matter of whether to elevate the possibility to head.

Findings: We also assess the influence of clarity of contribution on RFA success. To do so, we collected data on 754 RFA cases and used logistic regression to test four hypotheses.

Application/Improvements: Our results highlight the important role that user contribution behaviors and activity history have on the user’s success in the RFA process. The outcomes additionally propose that residency and number of RFA endeavors assume a part in the RFA procedure. Our discoveries have suggestions for hypothesis and practice.

Keywords

Requests for ADMINSHIP (RFA), Content Contribution, Administrators, Trust, Wikipedia, Social Contribution.

Full Text