Effect of PIN Diode Integration on Patch Antennas for Frequency Reconfigurable Antenna Applications

PIN diodes are commonly used to design reconfigurable antennas owing to their sufficient isolation, lower cost, and ease of fabrication. This study aims to explore the effect of biasing conditions of a PIN diode radio frequency (RF) switch on a frequency-reconfigurable antenna. This approach investigates the contribution of the forward diode current and the reversed biased voltage on the shift in the operating band, the impedance matching, and the radiation efficiency of a reconfigurable antenna. The benefits and drawbacks of different approaches to modeling PIN diode RF switches are demonstrated on Ansys electromagnetic switch. The result shows a significant match between simulated and measured operating bands, impedance matching, and radiation efficiency. The proposed RF switch model can be used as a practical simulation model for implementing various reconfigurable microwave components

Parasitic Element Based Frequency Reconfigurable Antenna with Dual Wideband Characteristics for Wireless Applications

A Microstrip Frequency Reconfigurable circular patch slot antenna for switchable Bluetooth, WiMAX, WLAN, and satellite communication applications is analyzed and presented in this work. The optimized overall size of 47 mm x40 mmx1.6 mm is utilized in the design, and which can cover wide range of frequencies below 10 GHz. In the initial phase, different monopole antennas are designed with various shapes of same size and later parasitic patch elements has been added to those monopole antennas. The circular monopole driven element and parasitic element are connected with a PIN diode, and which reinforced in achieving frequency reconfigurability. The proposed antenna is resonating at various frequencies of 2.4 GHz, 4 GHz, and 8.4 GHz when the diode in ON condition and resonating at 3 GHz, 5.4 GHz, and 8.4 GHz when the diode is in OFF condition. The performance of the designed antenna prototype is scaled and differentiated with the results of simulation and found good matching with respect to performance characteristics

Planar EBG Loaded UWB Monopole Antenna with Triple Notch Characteristics

A triple band-notched ultra-wideband (UWB) monopole antenna using a planar electromagnetic bandgap (EBG) design is proposed. The EBG unit cell composed by an Archimedean spiral and inter-digital capacitance demonstrates the notch frequencies. The antenna with EBG cells near the feed line occupies only 30 × 36 mm2 with triple band-rejection characteristics. The three notched bands at 4.2 GHz, 5.2 GHz, and 9.1 GHz can be used in C-band satellite downlink, wireless local area network (WLAN), and X-band radio location for naval radar or military required applications. In addition, the proposed design is flexible to tune different notched bands by altering the EBG dimensions. The parametric analysis is studied in details after placing the EBG unit cells near the feed line to show the coupling effect. The input impedance and surface current distribution analysis are also analyzed to understand the effect of EBG at notch frequencies. The proposed design prototype is fabricated and characterized. A fairly considerable agreement is observed between simulated and measured results

Compact Circularly Polarized Monopole Antenna Using Characteristic Mode Analysis

This study aims to design a circularly polarized compact antenna using characteristic mode analysis (CMA). The proposed antenna consists of a substrate with a slotted annular ring-shaped patch and partial ground. The excitation position of the antenna and its optimal dimensions are determined through the analysis of different operation modes with CMA. After that, an optimized antenna is designed, and an antenna prototype is fabricated for validation. The experimental results show that the reflection coefficient achieves a -10dB impedance bandwidth of 6.85 GHz, a 3dB-axial ratio bandwidth of 0.7 GHz, and a peak gain of 3.2 dBi. These characteristics agree with simulations and make the circularly polarized compact antenna suit for C-band and sub-6 GHz 5G wireless applications

Channel Estimation of FBMC Aux, FBMC and OFDM, based on BER and PAPR for 5G Systems

320-324In this generation of high-speed internet many research organizations are still busy finding the best candidate for the upcoming next generation of cellular mobile communication. These days mobile communication is divided into two parts, one is calling service and second is internet connectivity. Though many waveforms have been suggested for the fifth generation of mobile communication but out of which getting a compared output results on the basis of channel estimation is required. Through this research paper, FBMC Aux, FBMC, and OFDM are compared in terms of BER and PAPR to find our best candidate for future 5th generation mobile and data communication. A comparison of the time index is also done to verify the merits and demerits of the FBMC and FBMC Aux in this paper

GENETIC ALGORITHM-BASED CLUSTERING OF WIRELESS SENSOR NETWORK WITH NOVEL DATA ENCRYPTION

Wireless sensor networks (WSNs) have been used widely in so many applications. It is the most efficient way to monitor the information. There areso many ways to deploy the sensors. Many problems are not identified and solved. The main challenge of WSN is energy efficiency and information security. WSN power consumption is reduced by genetic algorithm-based clustering algorithm. Information from cluster head to base station may have a lot of chances to get hacked. The most reliable way to manage energy consumption is clustering, and encryption will suit best for information security. In this paper, we explain clustering techniques and a new algorithm to encrypt the data in the network

Determination of T Follicular Helper Cell Fate by Dendritic Cells.

T follicular helper (Tfh) cells are a specialized subset of CD4+ T cells that collaborate with B cells to promote and regulate humoral responses. Unlike other CD4+ effector lineages, Tfh cells require interactions with both dendritic cells (DCs) and B cells to complete their differentiation. While numerous studies have assessed the potential of different DC subsets to support Tfh priming, the conclusions of these studies depend heavily on the model and method of immunization used. We propose that the location of different DC subsets within the lymph node (LN) and their access to antigen determine their potency in Tfh priming. Finally, we provide a three-step model that accounts for the ability of multiple DC subsets and related lineages to support the Tfh differentiation program

Compact Circularly Polarized Monopole Antenna Using Characteristic Mode Analysis

This study aims to design a circularly polarized compact antenna using characteristic mode analysis (CMA). The proposed antenna consists of a substrate with a slotted annular ring-shaped patch and partial ground. The excitation position of the antenna and its optimal dimensions are determined through the analysis of different operation modes with CMA. After that, an optimized antenna is designed, and an antenna prototype is fabricated for validation. The experimental results show that the reflection coefficient achieves a -10dB impedance bandwidth of 6.85 GHz, a 3dB-axial ratio bandwidth of 0.7 GHz, and a peak gain of 3.2 dBi. These characteristics agree with simulations and make the circularly polarized compact antenna suit for C-band and sub-6 GHz 5G wireless applications

Evaluation of the Evan’s and Bicaudate index for South Karnataka Population using computed tomography

Background: Radiological markers that are useful in the diagnosis of normal pressure hydrocephalus include the Bicaudate index (BCI) and the Evans index (EI), which are practical indicators of ventricular volume. Worldwide, variation exists in normative studies for both these indices. The majority of research for EI and BCI is based on data from the Western population. The study has been performed on the South Karnataka population. Aims and Objectives: This study’s goal is to derive age and gender specific cutoff values on normative data of Evans and BCI. Materials and Methods: This was a prospective and observational study.Patients referred to “RL Jalappa Hospital” for computed tomography (CT) scan of the brain who meet the inclusion criteria will be included in this study. CT brain of all the patients will be performed in Siemens Somatom emotion 16 slice CT scanner. Ninety-seven were selected for this study, and EI and BCI were calculated for them. Results: The mean value of EI and BCI in our study was 0.26±0.02 and 0.1167±0.02, respectively. The difference in EI and BCI between males and females shown significant statistical difference between males and females but the values increased as increase in age. Conclusion: Our study for South Indian population concludes that EI and BCI have a significant statistical difference between males and females. Both EI and BCI values increase with age. Hence cutoff values of EI and BCI index according to age and gender are important for evaluation of hydrocephalus