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Quantum or optical DRAs are used as optical sensors in healthcare, high speed wireless communication and optical imaging solutions. Concept for monitoring the shift of frequency due to analyte mate...

Sensor design using ultra-wideband (UWB) technology is considered powerful emerging technique to extract information about the state of biological and physiological conditions of human organs for diagnostic purposes. Recently, UWB radio sensor technology is being proposed for early stage breast cancer detection in view of some superior characteristics or bio-markers over current methods. In this paper, a RDRA is designed, leading to develop the smart data acquisition system. A novel RDRA structure is simulated, which operates in the range of 3.7–7.4 GHz (67% bandwidth) which lies in the lower European UWB frequency band. The positive gain of the proposed antenna is stable across the active bandwidth and the peak value is 2.5 dB, which makes the RDRA structure highly suitable for body centric applications, especially for early detection of breast cancer. Thus, the proposed RDRA antenna structure can be integrated for early stage breast cancer detection application as well.

Ultra Wide Band technology has specifically endowed radio sensor technology in information retrieval of physiological conditions measured among various human organs. Radio sensors possess several characteristics in comparison of the contemporary counterparts. Due to which they are ardent candidate for detection of early stage of breast cancer. In this paper, the antenna structure highlights the hybridisation of Ring Rectangular Dielectric Resonator [RRDR] placed on multiple ring patch, which operates at a frequency band of 5.4–15 GHz. Impedance bandwidth of 94.1% is achieved with the hybridisation of patch and dielectric resonator antenna along with slotted ground structure. A peak gain of 5.7 dBi and high efficiency of 95% is achieved over the entire operating band which presented hybrid antenna is highly suitable for wearable and On-body communication. Breast Phantom is designed and Specific Absorption Rate (SAR) is calculated to check the feasibility of contemplated structure. Acceptable SAR and ringing free impulse response makes this antenna suitable for primitive breast cancer detection as well as Wireless Body Area Networks (WBAN).

The paper presents a novel method for the improvement in the bandwidths by mode merging of the circularly polarized dielectric resonator antenna (CPDRA). The results of improved axial-ratio bandwidth and impedance bandwidth is compared with the previous work. In this design, 50 $$\Omega$$ terminator diverts current in such a way that adjacent exited modes get merged. Also the upper order modes are merged to the lower order modes and a significant enhancement is achieved in overlapping bandwidth. The proposed CPDRA provides axial ratio bandwidth of 53.78% (axial ratio

Conical Terahertz DRA (dielectric resonator antenna) have been designed and investigated at terahertz spectrum i.e. 10 THz. Lower terahertz frequency band is useful for high data speed communication and upper band is used for optical sensors and free space wireless communications. Novelty in this work is to open up research in. terahertz. A unique geometry based dual band terahertz DRA with mathematical formulations has been proposed. The comprehensive analysis in terahertz regime have been worked out with S11, VSWR, radiation pattern and efficiency using conical TDRA. The conical terahertz DRA is designed at 10 THz frequency with 4.9 dBi, gain with bore sight radiation pattern. The equivalent circuit of conical terahertz DRA have been evaluated for dynamic impedance showing frequency dependence nature.

This paper presents a novel, compact Ultra Wide Band , Asymmetric Ring Rectangular Dielectric Resonator Antenna (ARRDRA), which is a unique combination of Thin Dielectric Resonator (DR), Fork shape patch and defective ground structure. The base of the proposed antenna is its Hybrid structure, which generates fundamental TM, TE and higher order modes that yields an impedance bandwidth of 119%. Proposed antenna provides a frequency range from 4.2 to 16.6 GHz with a stable radiation pattern and low cross polarization levels. Peak gain of 5.5 dB and average efficiency of 90% is obtained by the design. Antenna is elongated on a FR4 substrate of dimension 20 x 24x 2.168 mm3 and is particularly suitable for C band INSAT, Radio Altimeter, WLAN, Wi-Fi for high frequencies. Ease in fabrication due to simplicity, compactness, stable radiation pattern throughout the entire bandwidth are the key features of the presented design. Inclusion of Defective ground structure and asymmetric ring not only increases the bandwidth but also stabilize the gain and efficiency due to less surface current. Presented design launch an Ultra Wide Band antenna with sufficient band rejection at 4.48-5.34 and 5.64-8.33 GHz with stable radiation pattern and high gain.

Smartdielectric resonator antenna (DRA) having beam control mechanism is anew area to be explored by antenna researchers. Proposed new geometry DRA has low loss, design flexibility, high efficiency, compact size and desired radiated beam control. Developing beam control in new geometry DRAs is investigated for the first time in this letter. Unique technique for beam control and beam width control is proposed using pit top and mount top DRA. Gain is controlled from 5.0 to 9.98 dBi and beam is controlled from ±30° to ±70° in broadside radiation pattern. U shape pit DRA has maximum directive gain of 9.98 dBi and efficiency 98% at 5.8 GHz frequency. Measured and simulated results of radiation pattern and reflection coefficient are found to be in close proximity. Hardware of U shape pit top DRA, mount top DRA, left side arc top DRA, right side arc shape top DRA is developed and investigated. Mobile and cellular communication network need wide coverage, hence large beam width is required. Narrowing of beam width at higher order mode is also achieved.

Optical antenna is coming up technology in the field of nano technology. Fabrication at nanometer scale is still at infant stage in India. Human eye can be realized as antenna system. In this artic...

Equivalent R, L, C circuit is realized for DRA (dielectric resonator antenna) with mathematical solution. Resonant frequency, reflection coefficient, impedance and quality factor have been evaluate...

Cooperative Communication Systems and Relay Selection approaches are recent techniques of wireless communication system that enhance the quality of service (QoS). This research paper probes the execution of the Radio-Frequency and Free Space Optical (RF/FSO) Co-operative system using network of relays. The Co-operative relay system is typically composed of node of a source, the nodes of relays and node of a destination. The source and relay link (S-R link) follow the Generalized-K Fading distribution channel. The link connecting the relay node/device and the destination (R-D link) follows - Fading distribution channel. The relay is considered to adopt according to DF i.e Decode and Forward method of relaying and cooperatively assists in transmission to the destination node from the source node. The channel capacity is modelled using PDF (Probability Density Function) for the - distribution channel of fading for evaluation of the Dual-hop Asymmetric RF-FSO system. The performance and the analytical expressions of the new system proposed i.e. RF/FSO system were verified and validated using Monte Carlo simulation method.

A half-split inverted-frustum shaped two-port multi-input-multi-output (MIMO) dielectric resonator antenna is proposed with the ultra-wideband response. The antenna provides the impedance bandwidth of 132.69% (7 - 34.6 GHz) with each port. The MIMO performance parameters like envelope correlation coefficient, diversity gain, mean effective gain and channel capacity loss remain in the acceptable limits with the isolation more than 20 dB throughout the operating band. In addition, the antenna provides the peak gain ranging from 4 - 9.5 dBi at port-1 and 4 - 8 dBi at port-2.

The analysis of a circularly polarised (CP) dielectric resonator antenna (DRA) with the aperture coupled feeding technique is presented in this paper. Until now, the random techniques have been developed for obtaining the CP response in DRA. It is glaringly required to develop a fixed mathematical criterion for the selection of dimensions of the antenna structure. The criterion for selection of the stair-shaped slot dimensions, which is utilised for obtaining the CP response, is defined in this paper. The ranges of slot length ratios are investigated so that a wide CP bandwidth can be obtained. The antenna offers the 10-dB impedance of 58.62% (4.1 GHz - 7.5 GHz) and 3-dB axial ratio bandwidth of 40.86 per cent (4.26GHz - 6.385 GHz).

In this article, we present the study to improve the bandwidth of the dielectric resonator antenna (DRA) excited by aperture coupled feed by using a stacked DRA configuration above a ground plane. A wide dual-band stacked rectangular dielectric resonator antenna is also presented. The antenna consists of thirteen dielectric layers with different permittivity (er1 = 12.85 with 0.8 mm thickness and er2 = 4.4 with 0.8 mm thickness) and it is centrally fed by a rectangular slot on FR4 epoxy substrate er = 4.4 with 0.8 mm thickness. The numerical procedure is performed through a software package based on the finite-element method. An excellent agreement between simulated experimental results is observed. The concept of increasing the bandwidth of the DRA by stacking is verified with the proper excitation and selection of the resonator parameters, a wide bandwidth has been achieved for the stacked DRA configuration based on a − 10 dB reflection coefficient on a 50 Ω transmission line.

A new compact four-port multi-input-multi-output (MIMO) dielectric resonator (DR) antenna is proposed with pattern diversity. The antenna contains four DR elements, the epsilon-shaped and cylindrical. These four DR elements are placed together such that they resonate at the same frequency. The specific geometry of the DR elements allows to place them at separation which is much smaller than operating wavelength. Hence, the combination of the four DR elements acts as a single DR. This helps in maintaining the compactness of the antenna structure. The antenna operates with the hybrid of modes HEM 11δ and TM 01δ excited in epsilon-shaped and cylindrical DR elements, respectively. The excitation of these orthogonal modes helps in obtaining the pattern diversity allowing the antenna for multi-directional coverage. The antenna provides 15.73% overlapping 10 dB impedance bandwidth with the variation of gain within ranges 4-6 and 6-6.5 dBi at port 1/2 and port 3/4, respectively. In addition, the antenna provides the high radiation efficiency >93% at port 1/2 and 97% at port 3/4. Other parameters required for MIMO applications such as envelope correlation coefficient and diversity gain are within the acceptable limits.

A novel type of turtle-shaped dielectric resonator antenna is proposed for use in ultrawide-band applications. Nine layers of different shapes of slabs are integrated and excited through a conformal strip. This staired-pyramid-type structure provides a large surface area for higher radiation efficiency. The integrated antenna is built on a defected ground structure to enhance the bandwidth of the antenna. The simulations and measured results for a fabricated prototype antenna for use in ultra-wideband applications are found to be in good agreement. The proposed antenna operates from 3.0 to 10.9 GHz (bandwidth 7.9 GHz), providing an impedance bandwidth of 114%. The ultrawide bandwidth is achieved by proper mixing of lower and higher modes generated through the slabs.

A tunable single-/dual-band notch filter is proposed for THz applications. The filter geometry contains a proximity-coupled graphene patch. The filter structure operates with propagating- and nonpropagating-type transverse magnetic ( $$ {\hbox{TM}} $$ ) modes. Different higher-order $$ {\hbox{TM}}_{mn} $$ (where $$ m $$ and $$ n $$ are integers) modes can be excited in the filter structure by changing the aspect ratio of the graphene patch, thus enabling the filter response to be tuned to obtain single- or dual-band notch characteristics. Appropriate selection of the physical parameters of the filter structure allows the desired response at different frequencies to be obtained. Furthermore, the response of the proposed band notch filter can be tuned over frequency by changing the chemical potential of the graphene.

A technique is proposed to obtain the dual-band circularly polarised (CP) response along with the miniaturisation of a singly fed rectangular dielectric resonator (DR) antenna. The miniaturised response is obtained by applying the metallic strips on the sidewalls of the DR. The specific format of the applied metallic strips excites the orthogonal degenerate modes. Thus, a dual-band CP response is obtained along with the miniaturisation of antenna. The proposed antenna is designed to obtain the small frequency ratio. The frequency ratio can also be tuned by changing the surface area of the applied metallic strips.

This paper presents a novel design of antenna using sapphire. An aperture coupled two- layer stacked rectangular dielectric resonator antenna structure design consists of sapphire and TMM13i. Due to sapphire and TMM13i physical attributes such as hardness, resistance to physical change and chemical erosion the designed antenna is best suited for long distance, underground and rugged communication in addition to C band and 5G applications. The Aperture coupled feed has been employed because of its advantage of providing better isolation between antennas and the feed network. The designed antenna provides the gain of 5.2 dB and impedance matching of 50 ohms. The software High-Frequency Structure Simulator has been employed to simulate antenna design. The prototype of the antenna has been designed and tested on Vector Network Analyzer and Anechoic Chamber. The simulated results are in close proximity of tested results.

A proximity coupled wideband graphene patch antenna is proposed for THz applications. Antenna resonates with the closely placed higher order T M 1 δ modes ( 4 ≤ δ ≤ 12 or more). The generation of the large number of modes with resonant frequencies close to each other provides the wideband response. The wideband graphene antenna is modeled to obtain the optimum values of physical parameters. The antenna parameters are defined for the impedance matching and tuning of the frequency response. Varying the physical parameters, the antenna response can also be tuned to obtain the multiband response. The proposed antenna enables to achieve 109.25% impedance bandwidth.

In this paper the fabrication of the quantum CDRA at 3.37THz Frequency. Focus on simulation, design, micro fabrication and working on Lab-on-a-chip platforms i.e. Photonic Chip Integration Facility. It can be fabricated on single silicon wafer of 3” using micro machining for fabrication. The 3D printers are used to provide rapid prototype fabrication. The proposed quantum CDRA provides the return loss and VSSR of -30dB and 1dB respectively. The VSSR is below 2dB. The gain of the proposed quantum CDRA is 8.2 dB. The proposed quantum CDRA obtains impedance bandwidth of 5.27%. Proposed cylindrical dielectric resonator antenna can be used in LiDAR.

In this paper, we are proposing a miniaturization technique of rectangular DRA. In this technique, we are using a metallic patch to miniaturize the size of the RDRA. By changing the height of the metallic patch inside the DRA the resonant frequency of RDRA is significantly moved in backward way. Usually, the minimum height of metallic patch up to which an antenna can provide good radiation with good impedance matching is λ/10. Antenna does not allow expected radiation and also impedance will mismatch if the height of the metallic patch is belowλ/10. After applying the miniaturization technique, the field configuration of the fundamental mode inside the DRA is changed but the gain of the antenna remains constant. The tuning of the gain peak is possible with the antenna’s ‘resonant frequency.