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Circularly polarized designs of square microstrip antennas employing U-slot are presented in a 2400 MHz frequency spectrum. Design with a U-slot employing unequal lengths or the corner truncated patch with equal length U-slot yields axial ratio bandwidths of 3.84% and 2.2%, respectively. Against the conventional offset feed patches or the truncated corner square patches, the proposed designs decrease the frequency and patch size by 10% and 22%, respectively. Reduction in the frequency and patch area, while employing the U-slot is not being discussed in the reported papers on the circularly polarized designs, and hence it is the new contribution in the present study. The U-slot cut configurations exhibit a radiation pattern in the broadside with a gain of larger than 6 dBi across the complete reflection coefficient bandwidth. To obtain a wideband and circular polarized response using a single patch, a reconfigurable design of a corner truncated square patch employed with a U-slot is presented. A design methodology is presented based on the resonant length formulation to obtain reconfigurable U-slot cut design as per specific band start frequency in wideband response or center frequency in the axial ratio bandwidth in the circular polarized antenna. This helps to design these configurations for the specific frequency band. Simulated results in the proposed design are verified using the measurements that reflect a close agreement. [ABSTRACT FROM AUTHOR]

Blade antennas are used as transmitters in telemetry system of the sounding rocket RX-450 of Research Center for Rocket Technology - National Research and Innovation Agency to send rocket information to the ground station. For 360° coverage, the rocket needs two blade antennas connected with a splitter device which necessitates provision of additional power on the rocket payload. We designed a circular polarization conformal 2.4 GHz antenna to avoid both aerodynamic disturbances due to antenna shape and data transmission loss due to polarization loss with the ground station. The antenna material is Roger 6010LM and good antenna parameters were determined by simulation. The antenna bandwidth is 71 MHz (2412-2483 MHz). The maximum and minimum gain 7.8 dB at 2.43 GHz and 4.5 dB at 2.47 GHz respectively. Because of its conformal shape, we get an omnidirectional radiation pattern. Further, using the Hilbert curve method with a U-slot on the ground plane, circular polarization with an axial ratio = 2 dB is obtained. [ABSTRACT FROM AUTHOR]

5G stands for 5th generation network. It allows to connect people, machines, objects, etc. this paper will be talking about the design of a simple rectangular microstrip patch antenna for Ka bands and mmW applications at 35 GHz as operating frequency with dimensions 4.4 × 3.05 mm2 and we got after simulation some parameters such as bandwidth equals to 4 GHz, 5.3 dB as Gain, 6.5 dB as Directivity, 1.9 as VSWR (Voltage Standing Wave Ratio). Then, we have tried to improve those parameters by doing another design known as U slot antenna and we have achieved, bandwidth equals to 3 GHz, 6.08 dB as Gain, 7.16 dB as Directivity, 1.3 as VSWR. The proposed antenna has been made using FR4 material for substrate and has successfully improved the values of parameters because efficiency is 85% and is suitable for 5G applications. [ABSTRACT FROM AUTHOR]

This paper presents a dual-band printed monopole antenna backed with an electromagnetic band-gap (EBG) array for LTE, WLAN, Wi-MAX, and ISM band applications. The antenna is comprised of a T-shaped monopole, 50 Ω microstrip feed line, and a rectangular-shaped partial ground plane. The printed monopole antenna is supported by a 6 × 6 array of EBG unit cells, with each unit cell composed of square and circular rings, resulting in a wide impedance bandwidth and improved gain. The EBG-backed printed monopole antenna with partial ground plane offers an impedance bandwidth of 57.8% (1.6–2.9 GHz) and a maximum radiation efficiency of 95.4% with a peak gain of 6.9 dB in the first band, and an impedance bandwidth of 53.24% (3.39–5.85 GHz) and a maximum radiation efficiency of 95.2% with a peak gain of 8.7 dB in the second band. The proposed monopole antenna design is miniaturised, has less design complexity, and does not require vias for EBG realisation. [ABSTRACT FROM AUTHOR]

The SIW antenna suffers from the narrow bandwidth for a single cavity and single resonant. Defected ground structure (DGS) with a dual cavity was the solution to solve narrow bandwidth by resulting in hybrid resonance. The hybrid resonance with 14.83% impedance bandwidth is proposed in this antenna design. The first resonance resulted from the combination of the TE101 modes from inner and outer HMSIW cavities while the second resonance resulted from the combination of the strong TE101 and the weak TE102 mode from the inner HMSIW cavity and the addition of the weak TE101 from the outer HMSIW cavity. The measurement antenna design has a broadband antenna with a 14.31% (5.71 – 6.59 GHz) impedance bandwidth by using substrate Rogers RO 5880.

Circularly polarized gap-coupled variations of square microstrip antennas using U-slot are proposed in 2400 MHz frequency spectrum for WLAN and Bluetooth applications. Design with patches gap-coupled along the two coordinate axes provides the optimum results. It yields axial ratio bandwidth of 376 MHz (15.8%) with a maximum broadside gain of above 10 dBi. Design methodology based on the resonant length formulation is proposed that helps in designing similar antennas in other frequency bands. Measurements have been carried out to validate the simulated results that show close agreement. [ABSTRACT FROM AUTHOR]

The E-shape and U-slot cut microstrip antennas have been widely reported to obtain the wideband and circularly polarized responses. By combining these two design features, wideband and circularly polarized designs of E-shape and U-slot cut rectangular microstrip antenna that offer right hand and left hand wave response in the circular polarized spectrum are presented in this paper. The reconfigurable design approach is considered to achieve the same. By selecting a suitable excitation of the RF diodes, wideband response or circular polarized response is obtained. In 900 MHz frequency spectrum, on total substrate thickness of 0.07g, microstrip antenna offers impedance bandwidth of 22.07% and 21.64% while functioning in the wideband mode, in U-slot cut and E-shape patch. Using the reconfigurable E-shape design, it offers total 34.5% of input impedance bandwidth which contains 3.37 % of axial ratio bandwidth, towards the higher frequency band. Using the U-slot cut patch, these values are 31.5% and 1.35%, respectively. Reconfigurable approach combines the two operational features of the widely reported slot cut antenna thus providing the two responses using a single patch. Reconfigurable designs offer broadside radiation pattern with a peak gain of greater than 8 dBi. With the achieved antenna characteristics, proposed designs are useful in GSM applications in 800 - 1000 MHz frequency band. [ABSTRACT FROM AUTHOR]

Variations of U-slot and pair of rectangular slots (E-shape) cut rectangular and square microstrip antenna are reported for the circularly polarized response. In the reported literature, details about the functioning of the two designs in terms of the resonant modes present, with a comparison amongst them, are not discussed. This paper provides a detailed review-based study to explain the functioning of the resonant slot-cut circular polarized microstrip antenna in terms of the resonant modes present. This study reveals that TM11 mode in an E-shape microstrip antenna and degenerated TM10 modes in a U-slot design yield the circularly polarized response. Amongst the two, U-slot cut design offers stable gain characteristics across the axial ratio bandwidth and offers a dual-band frequency response. A design methodology based on the resonant length formulation is presented that helps in realizing both the circularly polarized configurations as per the given frequency of interest. Thus, the present work provides a detailed review-based study about the functioning of resonant slot-cut microstrip antenna and its design methodology, which is not discussed in the reported literature. [ABSTRACT FROM AUTHOR]

Antennas are an important component in wireless communication systems that continue to grow in the use of the 2.4 GHz frequency for 4G/LTE applications. Technology in the field of telecommunications has developed very rapidly using wireless communication, which is easily accessible by various devices, for example, Wi-Fi or Wireless Fidelity. Microstrip antenna is one type of antenna that has a narrow bandwidth, small gain. This research aims to widen the bandwidth by designing and manufacturing a truncated corner microstrip patch antenna with a 2x4 array at a frequency of 2.4 GHz with a U-slot. The truncated corner method is used to obtain circular polarization. The truncated corner microstrip antenna is designed by cutting corners. The array method is used to obtain the maximum gain value, while the addition of U-slot aims to reduce the return loss and Voltage Standing Wave Ratio (VSWR) values.

This article examines and studies the impacts of a U-shaped slot in the ground plane of a rectangular microstrip patch antenna with a finite ground plane. To build a compact patch antenna, the U-shaped slot's ideal size and placement have been considered. The size of the patch is 10.6 × 7.8 mm² and the size of the overall rectangular antenna structure is only 31.8 × 23.4 mm² including modified ground backside plane. The reference antenna's resonant frequency is 10 GHz and after the incorporation of U-shaped slot at the ground plane that resonant frequency lowered to 2.1 GHz. By the parametric studies almost 96 % compactness has been found possessing the slot’s optimum dimension. The improved antenna’s gain has been identified as 2.5 dBi. In this literature a study on compactness of rectangular microstrip antenna has been discussed and the effects of U-shaped slot on the finite ground plane over the resonant frequency, return loss and bandwidth have been analyzed. By adjusting various slot parameters in parametric research and selecting the best value of slot’s dimension and position, it has been determined that the modified antenna's resonance frequency is 2.1 GHz. [ABSTRACT FROM AUTHOR]

In this study, a compact U-slot patch antenna design based on dielectric measurement approach of Flame Retardant 4 (FR4) material is presented for X band space applications. In accordance with the design method, the measured frequency dependent dielectric constant and tangent loss values of the FR4 material at X-band using the waveguide method is applied to the HFSS design tool to be used in antenna designs. Then, the functional performance of the design method on antennas is verified by comparing the simulation and measurement results of a conventional antenna design in the literature. In the light of the verified results, a new U-slot patch antenna design with lateral side slots for X-band space applications is presented with a feed line by using the proposed design method. The presented compact antenna design provides 1.77 dB gain at the center frequency (9.5 GHz) and the frequency bandwidth from 8.53 GHz to 10.63 GHz. [ABSTRACT FROM AUTHOR]

Wideband and circular polarized designs of rectangular microstrip antennas employing offset positions of the U-slot and rectangular slot are presented. Query ID="Q1" Text="'EXTC' expand" An inter-spacing between the patch TM10, TM11 and TM02 resonant modes is optimized due to the presence of two offset slots that yields a wideband response with the presence of circular polarized bandwidth towards the higher frequencies, thus providing separate regions for the two responses. In 900 MHz spectrum, the proposed design yields maximum impedance bandwidth of 298 MHz (32.07%) with an axial ratio bandwidth of 13 MHz (1.26%). The proposed designs exhibit pattern maximum in the broadside direction with a gain of larger than 6 dBi. Simulated results have been verified using the experimentation, which shows close agreement. [ABSTRACT FROM AUTHOR]

A penta-mode concept is proposed for the design of single-fed ultrawideband circularly polarized (CP) antennas. The concept involves five linearly polarized (LP) modes in a way that each two adjacent LP modes are designed with orthogonal polarizations of equal amplitude and quadrature phase difference. In this manner, each LP mode is shared by two LP modes nearby except for the first and the last mode in the band. As a result, the CP bandwidth is significantly improved. For proof of concept, a stacked U-slot patch antenna is proposed and designed with a characteristic mode analysis (CMA). The five modes are designed by optimizing the U-slot and the coupling between stacked patches. With the single-fed CP antenna element, a $2\times $ 2 CP array is further designed and prototyped. The measured CP bandwidths of antenna element and array are 52.7% [within 2:1 voltage standing wave ratio (VSWR) and 3 dB axial ratio] and 74% (within 2:1 active VSWR and 3 dB gain), respectively, a significant improvement compared with the conventional CP stacked structures of similar thickness or volume. [ABSTRACT FROM AUTHOR]

In this paper, a compact dual-band multipleinput multiple-output (MIMO) diversity antenna is proposed. Each of the two MIMO antennas consists of two folded strips working as radiating elements that are fed by a microstrip line. The antennas operate in three WLAN bands: ISM 2.45 GHz, 5.25 GHz, and ISM 5.775 GHz. To improve the isolation at WLAN (2.4-2.48 GHz), two L-shaped slots are etched in the ground plane while a U-shaped slot is cut in the ground plane to enhance isolation at WLAN (5.15-5.35 GHz and 5.725-5.825 GHz). Three slots on the substrate between radiating patches are also employed for an extra reduction in the mutual coupling at 2.45 GHz. The antenna performance was examined by simulation employing CST Microwave Studio Software. The proposed antenna offers minimum isolation of more than 19.5 dB, a low envelope correlation coefficient (ECC) of less than 0.0016, and good radiation efficiency (-80%) through the operating frequency bands. The antenna is compact, thin, and suitable for portable devices. [ABSTRACT FROM AUTHOR]

One of the major drawbacks of the U-slotted wideband microstrip patch antennas, i.e., the polarization instability at the high-end frequencies, is addressed by utilizing the next broadside TM12 mode in circular patch antennas. The proposed antenna is capable of generating stably polarized waves over a wide frequency range of ~45% (2.05–3.25 GHz), which is not the case with the reported literature on U-slotted wideband patch antennas. The antenna comprises the U-slot and appropriately positioned shorting vias to achieve the desired impedance and radiation characteristics. It is fed by an L-probe and loaded with four non-resonating arc slits to suppress the TM12 mode’s E-plane sidelobes, which are very prominent otherwise. The polarization stability of the antenna is demonstrated through the surface current distributions on the patch, radiation patterns, and the x- and y-polarized gain over the frequency range of interest. [ABSTRACT FROM AUTHOR]

This paper presents to enhance the input impedance matching of the rectangle microstrip patch due to the dwindling of the surface waves. The properties of this antenna have been enhanced by the enhancement of the input impedance matching. This is to achieve with the use of three techniques, which are the defective ground structure, intrude a U-shaped slot on a patch, and 1-D EBG structure. This antenna has designed on both sides of the FR4 epoxy substrate of a thickness of 1.6 mm at 2.4 GHz to the simulation and fabrication. The results of this antenna have been good agreement between both the simulations and fabricate designs. This antenna can applicable to LTE (4G), WiFI, WiMax, UMTS, and 3G/2G mobile communications. [ABSTRACT FROM AUTHOR]

A triple band-notched monopole antenna with reconfigurable characteristics is designed and investigated in this study for implementation in ultra-wideband (UWB) systems. A conventional rectangular monopole antenna is intended first to accomplish UWB performance characteristics. Further, to obtain triple notched characteristics, three U-shaped slots are etched on the rectangular radiating surface of the antenna. A wide frequency bandwidth ranging from 2.13 GHz to 10.50 GHz with three notched bands operating at 2.65 GHz (2.49–2.82 GHz), 3.43 GHz (3.18–3.68 GHz), and 4.08 GHz (3.93–4.22 GHz) have been successfully realized. By integrating three PIN diode switches, total eight reconfigurable states of operations have been realized in the UWB spectrum. A thorough analytical investigation along with the comparison of simulated and measured performances for the proposed antenna has been presented to manifest the applicability in practical systems. The antenna structure can be successfully implemented for rejecting interferences from dual WiMAX bands along with C-band fixed satellite communication systems, respectively. [ABSTRACT FROM AUTHOR]

In the presented paper, the printed patch antenna is used for the various applications in the wireless communication systems. Printed patch antenna has several negatives for the use of microwave frequency as low efficiency, low gain and low bandwidth. The parameters of this antenna are very complex in tuning. Due to this, various slots is used for improvement of antenna performance. The variety of slots is used in microstrip patch antenna for the high frequency applications which makes the antenna suitable for the wireless communication systems. This paper provides a double U-slot and a defected ground structure for the improvement of bandwidth, gain and various other parameters. [ABSTRACT FROM AUTHOR]

A printed monopole filtenna fed by a co-planar waveguide with U-shaped split slot on patch and circular split ring resonator pairs at the other side of feed is proposed in this letter. The compact filtenna of dimension 0.32λ × 0.215λ (λ denotes wavelength corresponding to 2.68 GHz) is capable of providing large bandwidth from 2.68 to 8.72 GHz with dual frequency notch bands over 3.28–3.84 and 4.95–6.02 GHz, primarily to eliminate the WiMAX and WLAN interferences. The dual notched antenna performances are evaluated by simulation and experimental measurement and compared to those of recently reported ultra-wideband (UWB) notched antennas. The proposed filtenna provides bidirectional E-plane and omni-directional H-plane radiation patterns with gain variation of 2–4.5 dBi and average radiation efficiency of 78% in its pass band. Also the filtenna offers minimal dispersion characteristic as stable group delay response, and linear variation of transfer function (S21) is achieved in its pass bandwidth. [ABSTRACT FROM AUTHOR]

A low-profile, high-gain, and broadband U-slot cut artificial magnetic conductor (AMC) loaded patch antenna is presented in this letter. The wideband performance is achieved by strategically cutting two rectangular slots and inserting four strips onto a conventional AMC ground plane. Moreover, a defected ground structure is used to reduce the antenna size. As a result, four reflection zeroes are obtained within the antenna | $S_{11}$ | curve. The antenna is characterized by a low profile ($\boldsymbol{h}/{\boldsymbol{\lambda }_0}\sim 0.05$ , ${\boldsymbol{\lambda }_0}$ is the free-space wavelength at the center frequency), wide bandwidth 58.6%, light weight, low cost, and wide 10 dBi gain bandwidth. The presented antenna is suitable for C-band satellite (3.7–4.2 GHz), 5.15–5.35 GHz WLAN, and the 5G in 3–6 GHz band applications. [ABSTRACT FROM AUTHOR]

Abstract Wide band designs of E-shape and U-slot cut Rectangular Microstrip antennas are discussed which yields bandwidth of 207 (23%%) and 174 (19%) MHz, respectively. For further bandwidth enhancement, various designs of E-shape and U-slot cut rectangular patch antenna with tapered patch width are proposed. Tapering in patch width alters the input impedance at TM 10 mode in E-shape patch and at TM 10 and TM 02 modes in U-slot cut rectangular patch that yields increase in the bandwidth. Tapered design of E-shape patch gives bandwidth of 225 MHz (~26%) and that of U-slot cut patch yields bandwidth of 202 MHz (~22%). In another tapered width design of E and U-slot cut RMSAs, patch width is reduced at both the ends and these designs yields bandwidth of above 270 MHz (29%) and 212 MHz (22.2%), respectively. The varying width patches exhibit broadside radiation pattern with moderate increment in the values of broadside antenna gain. [ABSTRACT FROM AUTHOR]

Abstract Novel design of Phi-shape microstrip antenna for circular polarized response is presented. The placement of dual stubs in Phi-shape structure optimizes the spacing between degenerated orthogonal TM 11 modes of equivalent circular ring patch that yields circularly polarized response. With reference to patch dual orthogonal TM 11 modes and next higher order TM 21 mode, Phi-shape patch yields VSWR bandwidth of nearly 700 MHz (> 55%) with AR BW of 56 MHz (5.64%). The antenna gives broadside radiation pattern with peak broadside gain of above 8.5 dBi over the VSWR bandwidth. [ABSTRACT FROM AUTHOR]

A novel coaxial fed multilayered antenna is designed to operate at multiband operation in this article. The designed antenna consists of defected ground in the bottom plane of lower substrate and W-shaped patch on the top. U-shaped patch is placed on the top layer of the upper substrate and coaxial feeding is used in this design to excite the lower patch. The proposed antenna is operating in the application bands of GSM and PCS (0.9-1.2 GHz), Bluetooth, ISM and LTE (2.4-2.6 GHz), Wi-Fi (3.2-3.6 GHz), Lower band of WLAN (4.8-5.2 GHz), Upper band of WLAN (5.8-7 GHz) and Satellite applications (10.2-11 GHz). Antenna providing peak realized gain of 4.5 dB and peak efficiency of 80%. The prototyped antenna giving excellent correlation results with simulation results obtained from HFSS tool. [ABSTRACT FROM AUTHOR]

The Theory of Characteristic Modes (TCM) is proposed as a systematic approach to antenna design to achieve the goal of finding the antenna structure with optimum broadband behavior. This theory provides a physical insight to the radiating nature of microstrip patch antennas and reduces the design optimization time. In this work, the resonant behavior of the highly radiating structure of the single U-slot rectangular patch on a single-layer εr = 4.4 substrate is analyzed using TCM. Modal analysis of this single-layer structure with different single feed excitations concludes that VSWR ≤ 2 impedance bandwidth in the order of 96% can be achieved with a single T-probe feed. Experimental results, included here, show VSWR ≤ 2 impedance bandwidth in the order of 71%. [ABSTRACT FROM AUTHOR]

Abstract: A single layer single probe‐fed wideband microstrip antenna is presented and investigated. By cutting a U‐slot in the rectangular patch, and by incorporating two identical U‐shaped parasitic patches around both the radiating edges and the nonradiating edges of the rectangular patch, three resonant frequencies are excited to form the wideband performance. Details of the antenna design is presented. The measured and simulated results are in good agreement, the measured impedance bandwidth is 1.44 GHz ( 4.82 ‐ 6.26 GHz), or 26.2 % centered at 5.5 GHz, which covers WLAN 5.2 GHz ( 5.15 ‐ 5.35 GHz), WLAN 5.8 GHz ( 5.725 ‐ 5.825 GHz), and WIMAX 5.5 GHz ( 5.25 ‐ 5.85 GHz) bands. The measured peak gains at the three resonant frequencies are 7 . 73 dB, 7 . 01 dB, and 4 . 55 dB, respectively. An equivalent circuit model which is based on the transmission line theory, the asymmetric coupled microstrip lines theory, and the π‐network theory is established. This equivalent circuit model is used to give an insight into the wideband mechanism of the proposed antenna, and is also used to explain why the three resonant frequencies shift at the variations of different parameters from a physical point of view. The error analysis is given to demonstrate the validity of the equivalent circuit model. [ABSTRACT FROM AUTHOR]

Ultra-wideband (UWB) phased arrays are increasingly used in radar and medical applications. Mutual coupling reduction between the phased array elements is critical in achieving good scan bandwidth. This study investigates the mutual coupling of a UWB U-slot microstrip patch 2-element array to find the patch orientation and U-slot topology with the least mutual coupling. Electromagnetic (EM) simulation results indicate that, for εr = 2.2 substrate, diamond patch orientation with opposite U-slot topology has the least coupling between the array elements. Results also indicate that the current density distribution on the microstrip patch has an effect on mutual coupling between the array elements. Results show good agreement between MoM and FEM EM solvers. [ABSTRACT FROM AUTHOR]

Broadband microstrip antenna using variations of U-slot has been widely reported. However, in most of the reported work, an in-depth explanation about the mode introduced by U-slot and procedure to design U-slot cut antennas at any given frequency is not explained. In this paper, first an extensive analysis to study the broadband response in symmetrical and a new configuration of asymmetrical U-slot cut rectangular microstrip antennas is presented. The U-slot tunes higher-order orthogonal mode resonance frequency of the patch with respect to fundamental mode to realise wider bandwidth. Further formulation in resonant length at modified patch modes in symmetrical U-slot cut antenna is proposed. Frequencies calculated using these formulations show closer agreement with simulated and measured results. Using proposed formulations, a procedure to design U-slot cut antenna at different frequencies over 800-4000 MHz range which shows broadband response is explained. Thus, the proposed work gives an insight into the functioning of widely used U-slot cut antennas and the formulations will be helpful for designing at any given frequency. [ABSTRACT FROM AUTHOR]

This letter presents design of a compact (0.32λg × 0.15λg) dual frequency rectangular microstrip patch antenna for wireless applications. Dual frequency operation is achieved by inserting a pair of symmetric face-to-face U-slots, which results in excitation of [ABSTRACT FROM AUTHOR]

In this study, a 28-GHz U-slot array antenna for a wideband communication system is proposed. The U-slot patch antenna structure consists of a patch, two U-shaped slot, and a ground plane. With the additional U-slot, the proposed antenna has around 10% of bandwidth at -10 dB. To increase gain, the U-slot antenna is arrayed to 2×2. The proposed antenna is designed and fabricated. The 2×2 array antenna volume is 41.3 mm × 46 mm × 0.508 mm. The proposed antenna was measured and compared with the simulation results to prove the reliability of the design. The bandwidth and gain of the measurement results are 3.35 GHz and 13 dBi, respectively and the operating frequency is around 28 GHz. [ABSTRACT FROM AUTHOR]

The need for low-profile and ultra-wideband (UWB) antennas is rising in wireless communication and medical applications. The method of dimensional invariance, which is a class of U-slot patch design methods, is utilized to realize an initial, low-profile, wideband design. Building on this initial wideband design, this study establishes ideal L-probe feed dimensions through extensive parametric study on εr = 2.2 and 4.5 substrates to propose empirical guidelines for the design of L-probe feeds which yield first-pass optimum impedance bandwidth. The established ideal L-probe dimensions, after further extrapolation, are used successfully on other substrates, εr = 3.27, 6.0 and 9.2, for the design of first-pass L-probe feeds which yield impedance bandwidth over 55%, 60%, and 53%, respectively. The results of three commercially available EM simulation solvers show good agreement [ABSTRACT FROM AUTHOR]

A low-profile microstrip-fed planar monopole ultra-wideband (UWB) antenna with triple band rejection characteristics is proposed. The proposed antenna configuration consists of a bevelled ground with multiple U-slots embedded on the radiation patch for realizing the band notch characteristics. The notched frequency bands can be controlled by adjusting the parameters of the slots. The measured results demonstrate that the fabricated antenna exhibits an impedance bandwidth from 3 to 11 GHz for a VSWR ˂ 2 with three rejection bands at 3.38‒3.73 GHz for WiMAX, 5.12‒5.84 GHz for WLAN and 7.23‒8.56 GHz for X-band satellite communication services. Band rejection function is confirmed by the three gain diminishes occurring at 3.7, 5.35, and 8 GHz and stable gain outside the rejection bands. Measured group delay ensures that the designed antenna has good transmission capability of UWB signal with minimum distortion. [ABSTRACT FROM AUTHOR]

ABSTRACT A thin, single substrate layered, dual directionally isolated band Meander line antenna (MLA) with connected ends, widened near the feed area, loaded by a U-slot in the patch layer, and by a modification from complementary split ring resonator (CSRR) in the ground layer, is presented for WLAN applications. © 2016 Wiley Periodicals, Inc. Microwave Opt Technol Lett 58:895-901, 2016 [ABSTRACT FROM AUTHOR]

A new design for single-feed dual-layer dual-band patch antenna with linear polarization is presented in this letter. The dual-band performance is achieved by E-shaped and U-slot patches. The proposed bands of the antenna are WLAN (2.40-2.4835 GHz) and WiMAX (3.40-3.61 GHz) bands. The fundamental modes of the two bands are TM01 mode, and the impedance bandwidths ( ) of 26.9% and 7.1% are achieved at central frequencies of 2.60 and 3.50 GHz. The peak gains of two different bands are 7.1 and 7.4 dBi, and good band isolation is achieved between the two bands. The advantages of the antenna are simple structure, wideband performance at low band, and high gains. [ABSTRACT FROM PUBLISHER]

Half-width microstrip leaky-wave antennas (HW-MLWAs) are generally single band. Here, we present a new method to achieve dual-band operation from an HW-MLWA by periodically loading the antenna with U-shaped slots. These dual-band MLWAs are able to steer the beam in forward directions in one band and in backward directions in the other band. One of the antenna designs was prototyped and tested, and excellent agreement between the predicted and measured results were observed. The measured 10-dB return loss bandwidth of the first and second bands are $19.5 \% $ (5.24–6.37 GHz) and $13.2 \% $ (7.9–9.02 GHz), respectively. The antenna can steer the main beam from $30^\circ $ to $65^\circ $ in the first band and from $-46^\circ $ to $-10^\circ$ in the second band by sweeping the frequency from 5.25 to 6.25 GHz and 7.75 to 9 GHz, respectively. The measured peak gain of the antenna is 12.2 and 14.1 dBi in the first and second bands, respectively. Although the antenna parameters are optimized for dual-band operation, the radiation properties in another higher frequency band (third band) are also explored. In the third band, the antenna beam continuously scans from backward to forward direction as frequency increases. Moreover, this U-slot loaded single-layer half-width LWA is easy to fabricate. [ABSTRACT FROM PUBLISHER]