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Patch antennas come in various shapes and sizes and consist of a patch of metal directly above a ground plane. Figure 5/27 shows an example of a patch antenna. The main disadvantage of these antennas is their relatively large size compared to other types of antennas. For example, some patch antennas are approximately half a wavelength on each side. The polarization can be either circular or linear depending on the design of the patch. In a patch antenna, most of the propagation is above the ground plane and can have high directional gain.

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  • Q-band and H-bband antenna
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  • Design of an H-shaped Microstrip Patch Antenna for Bluetooth Applications
  • Conformal antennas are usually microstrip antenna, stripline antenna, or crack antenna
  • Design of E-Shape Patch Antenna & its Array using IE3D Software
  • The design uses microstrip patch antenna as radiation elements
  • Miniaturization and Feeding Techniques of H-shaped antenna
  • Dual Annular Ring Coupled Stacked Psi Shape Patch Antenna for Wireless Applications
  • Frequency Reconfigurable Circular Patch Antenna with an Arc-Shaped Slot Ground Controlled by PIN Diodes
  • Analysis of a Full E-Shaped Antenna

The easy feed technique is one of the useful characteristics of microstrip patch antennas in wireless applications. The microstrip patch elements of an array antenna can be fed using a single line or multiple lines depending on the requirement of the system. There are various complex types of feeding techniques as well. Reference presented a four-element dual-band printed slot antenna array for 5G which is fed using a modified Wilkinson power divider. In , wideband E-shaped microstrip patch antenna with folded-patch feed in proposed. In both cases, the feeding techniques are of complex nature, whereasa series network is a simple type of feed network that consists of a continuous transmission line through which a proportion of energy is progressively coupled into each element of an array along the line. In , a series feed technique has been employed to feed a 4 × 4 planar microstrip array antenna with a modular structure and small dimension that can operate in 5G networks at 28 GHz. In , a modified 3 × 3 series-fed patch array antenna capable of beam steering is presented for 28 GHz millimeter-wave applications.

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This paper presents a novel design of polygon shaped microstrip slot antenna for dual band operation. The dual bands are achieved by placing ring slot in the conventional polygon microstrip antenna. The impedance bandwidth of each operating band is found to be 6/58% and 27/53%. These bands are enhanced to 22/68% and 36/03% respectively by truncating two corners of polygon patch, which also reduces the overall size of the patch by 27/48% when compared to conventional square microstrip antenna. The enhancement of impedance bandwidth does not affect the nature of broadside radiation characteristics. Design concept of antennas is given and simulation results are discussed.

The Antenna Toolbox has several antenna (https://yamamotonight-m.ru/content/uploads/files/download/e-shaped-patch-antenna-pdf.zip) elements that could provide hemispherical coverage and resemble a pattern of cosine shape. Choose a patch antenna element with typical radiator dimensions. The patch length is approximately half-wavelength at 77 GHz and the width is 1/5 times the length to improving the bandwidth.

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Two triangular shaped slots and one rectangular slot along the diagonal axis of a square patch have been embedded. Due to slotted structure along the diagonal axis and less surface area, good quality of circular polarization has been obtained with the reduction in the size of microstrip antenna by 4/04 %. Circular polarization radiation performance has been studied by size and angle variation of diagonally slotted structures. The experimental result found for 10-dB return loss is 44 MHz with 10MHz of 3dB Axial Ratio (AR) bandwidth respectively at the resonant frequency 910 MHz.

The first sidelobe level is higher, which cannot meet the design requirements. We need to find the appropriate spacing between elements to meet the main beam deflection. Then the current distribution is designed to reduce the sidelobe level.

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Design & Analysis of C-Shaped & Circular Microstrip Patch Antennas

A microstrip patch is one of the most widely used radiators for circular polarization. Figure 3/1shows some patches, including square, circular, pentagonal, equilateral triangular, ring, and elliptical shapes which are capable of circular polarization operation. However square and circular patches are widely utilized in practice. A single patch antenna can be made to radiate circular polarization if two orthogonal patch modes are simultaneously excited with equal amplitude and out of phase with sign determining the sense of rotation. Two types of feeding schemes can accomplish the task as given in figure 3/2. The first type is a dual-orthogonal feed, which employs an external power divider network. The other is a single point for which an external power divider is not required.

Rectangular patch antenna hfss

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The designed array has satisfied the requirement of the main beam offset, but the sidelobe level is still too high. The feeding position is in the middle of the array, which satisfies the design of Taylor distribution. The design of Taylor distribution is carried out based on this array. The model diagram is shown in Figure 14; plane is the plane of the array.

In present work, a novel miniaturized design of a multi frequency rectangular microstrip patch antenna is designed and simulation results are presented in this paper with broadband behavior for WLAN and HYPERLAN and SATELLITE applications is proposed. The proposed antenna has Multi frequency bandwidth of about 385 MHz (3/282-3/672GHz), 517MHz (5/1145/631GHz) and 1111 MHz (5/917-7/028GHz) at -10 dB return loss which is sufficient to make the antenna useful for WLAN/ HIPERLAN/ SATELLITE operation. The maximum achievable gain over the entire frequency band is close to 5 dBi. The resonance frequencies can be controlled by adjusting the dimensions of the ground plane. The proposed antenna uses a pi-shaped slot made into the ground. The key parameters like return loss, input impedance, gain are simulated, analyzed and optimized using High Frequency structure Simulator (HFSS) v11. The results show that the preference of the proposed antenna can be greatly improved compared to traditional microstrip patch antennas.

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Related Manuals for Shure PG4

Defected ground structure (DGS) is widely used to suppress the cross-polarization [12,13,14,15]. Recently, in , Kumar et al. presented a rectangular DGS to suppress the cross-polarization of a graphene-based antenna in the elevation plane. In , a dumbbell-shaped DGS is reported to achieve a co-cross-polarization isolation of more than 30 dB for a rectangular patch antenna. Similarly, in [14,15], different DGS structures are employed to suppress the cross-polarization of rectangular patch antennas. However, a few other techniques such as aperture coupling , metamaterial based [17,18], and differential feeding , are also reported in the literature to suppress the cross-polarization of non-conventional antennas.

Here working frequencies are 1/9 GHz and 2/0 GHz. Rectangular patch shape technique is used for designing this microstrip antenna. In our model electric field lines, conductance and input resistance have obtained by transmission line model whereas charge distribution, directivity and g.

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Multi Antenna Design for MIMO Mobile Communication System

Firstly, we choose dielectric substrate. For microstrip circuit, the loss of the microstrip is very large in the millimeter-wave band. The loss can be divided into dielectric loss, conductor loss, and radiation loss . Substrates with low loss tangent dielectric are usually chosen to reduce the dielectric loss. When the dielectric constant is low, the total loss of the microstrip would not change with the characteristic impedance. On the contrary, when the substrate has high dielectric constant, the loss of the microstrip will change rapidly with the characteristic impedance. Thicker substrate will increase radiation losses and the surface wave is more serious. A smaller height is more effective in suppressing the higher mode and reducing the radiation loss. Additionally, the thinner substrate with good flexibility is good for conformal antenna .

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The Delphi NAV300 sports a design that's slightly revamped over its predecessor's. The overall shape is the same, but it's slightly more narrow and heavier at 4/6 inches wide by 3/1 inches tall by 1/1 inches deep and 7/6 ounces, compared to NAV200's 5/3 by 3/2 by 1 inches and 6/7 ounces. The system also retains the flip-up patch antenna on the back, rather than integrating the receiver into the device. We much prefer the latter, since it looks neater and you don't have to worry about lifting the antenna every time, but it's certainly not a deal-breaker. The Delphi NAV300 is still a compact and ultraportable unit, so you should have no problems transporting it between vehicles.

A real crack in a building could be modelled with a line air gap with width of 5 mm as depicted in Figure 5(a). From Figure 5(b), it could be seen that the algorithm was able to reconstruct the line target. The similar crack model was constructed by breaking a brick into two unequal halves and putting them back together side by side. The result from the real brick shows a vague line that could match the irregular crack line of the brick. With bare eyes the line was hardly visible; however, if it would be processed further with image processing tool such as using edge detection technique, the crack could be better detected.

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Detection of Cracks in Concrete Structure Using Microwave Imaging Technique

Wireless communication has been growing exponentially over the last decade, where multimedia application, satellite and radar communication have developing with it, as well as demand for multitask features in same device has drawn attention to the consumers. Integration of Microstrip Patch Antenna in wireless equipments helps to fulfill requirement due to its miniature dimension, robustness and inexpensive attributes. In this paper, a modified slots loaded with E shaped patch antenna with dielectric substrate layer on the top has been illustrated. The proposed antenna has the capability to operate in eight different multiple frequencies having single radiator. The antenna has been design on the top of the dielectric substrate of permittivity 4/3 and thickness of 1/6mm. The proposed antenna resonates at 5/54 GHz, 6/51 GHz, 7/75 GHz, 8/15 GHz, 10/49 GHz, 11/98 GHz, 12/96 GHz and 16/11 GHz with impedance bandwidth of 44/51 MHz, 33/28 MHz, 330 MHz, 102 MHz, 1/101 GHz, 483 MHz and 4/532 respectively that covers C, X and Ku band. The design scheme and simulation results of proposed antenna are presented.

The third step is to reduce the sidelobe level. The antenna design is based on 8-element linear array. Because of the need to achieve the main lobe deviation, the distance between the radiating elements is consistent. The sidelobe amplitude can be reduced by controlling the current. The current amplitude distribution design is based on the Taylor distribution [21, 22].

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The same defect model was constructed and measured in the lab using the configuration shown in Figure 2. A 70 × 70 × 220 mm cement brick was used as the phantom. The measurement setup consists of vector network analyzer (VNA), 16 wide-slot antennas , 20 dB wideband amplifiers, and a multiplexer.

Fig. 2 Structure of theProposed Stacked E-shaped Patch Antenna AN OPTIMISED STACKED E-SHAPED PATCH ANTENNA

The research thesis is aimed towards the designing of a compact printed ultra wideband antenna (UWB) with dual band notched characteristics. It is a planar monopole micro-strip fed designed antenna structure. The radiating patch is rectangular in shape with a partial ground plane. The 3/0 GHz Wi-max band is rejected in addition to the 5/0 band used in Wireless Local Area networks (WLAN’s). Simulation is done using the “High Frequency Structure Simulator” and the measured values are analyzed. The results obtained after using the optimized parameters depict UWB characteristics while rejecting the two bands frequencies.

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Several CubeSat antennas are designed based on the patch topology due to its size and mass and planar compliance. The antenna was developed on the same Rogers substrate with two different thicknesses: 1/52 mm and 0/508 mm. A rectangular shape was chosen to comply with the CubeSat chassis structure, resulting in a gain of 7/3 dBi and directivity of 8/3 dBi at 2/4 GHz .

To test the resolution of the system, several FDTD models with different crack size, positions, and orientation were simulated. Firstly, a two-dimensional model of a brick with a single 5 mm or diameter hole was simulated. Comparing between the model and the reconstructed image in Figure 1, it can be seen that the hole has been properly reconstructed at the right position; however, its shape appeared to be a little distorted with some clutter around it.

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The three GRAS antennas are pointed in the satellite's velocity, anti-velocity, and zenith directions. The GVA (GRAS Velocity Antenna (https://yamamotonight-m.ru/hack/?patch=3226)) and the GAVA (GRAS Anti-Velocity Antenna) are phased arrays, each containing 18 dual-band patches with a shaped antenna pattern optimized for the occultation of the Earth's limb and its atmosphere.

Shure PG4 Service Manual

Table 2 summarizes some key indicators of the proposed antenna and other wideband CP antennas. The antenna proposed in is fed by a single feed point. The antenna proposed in is fed equivalently by two feed points. To improve the AR of the antenna in , a reactive impedance surface is used. To improve the AR of the antenna in , an L-shaped parasitic patch and four parasitic patches are used. In , a wide 3-dB AR bandwidth of 31% is achieved by generating an equivalent four-point feeding. It is observed that the more the feeding points, the easier it is to obtain a wider 3-dB AR bandwidth (27/5% in , 28/1% in , and 31% in ) and a wider impedance bandwidth (44/5%% in , 38% in , and 60/5% in ). In this paper, an equivalent six-point feeding and a parasitic patch are used to extend the impedance and 3-dB AR bandwidths. Compared with the CP antennas in [5, 9–16, 19, 20], the proposed antenna has a wider 3-dB AR bandwidth and better impedance matching. The peak gain of the proposed antenna is 9/76 dBic, which is a good result. Although the antenna in has a greater peak gain, the size is larger than that of the proposed antenna.

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Multiple-input multiple-output (MIMO) technology is originated from wireless communication antenna diversity technology and intelligent antenna technology. It is a combination of multiple-input single-output (MISO) and single-input multiple-output (SIMO) and therefore has the advantages and characteristics of the two [1, 2]. The MIMO system is equipped with multiple antennas at the transmitter and the receiver. It can improve the quality of wireless communication and the rate of data exponentially without increasing the bandwidth and transmitted power [3, 4]. Multiantenna system is an important part of MIMO technology. MIMO wireless system is not only affected by the multipath characteristics of the wireless communication channel but also depends on the design and layout of the multiantenna system. The research of MIMO multiantenna design mainly includes the form of antenna element, the layout of multiple antennas, and the mutual coupling analysis. At present, the research of MIMO multiantenna is focused on the exploration of low cost and high performance designs of antenna and layout [5–7].

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Where is the distance between the radiating elements and is the effective wavelength in the medium. When the distance, the main lobe biases feed; otherwise, it biases load. Element spacing is an important parameter influencing the radiation characteristics of an antenna array.

Micro strip antenna consists of very small conducting patch which can take any possible shape like square, triangular, circular, and rectangular. In this paper Square Micro strip Patch antenna is used because square patch antenna (home) have few benefits, including the cheap price, flexibility, and ease of manufacture. To achieve high directivity, low profile nature is obvious as well as small size of antenna is required. Metallic patch placed on a small portion of wavelength above a ground plane. Dielectric substrate material separates the two, the patch element and the ground plane. The radiating patch and the feed lines are designed on the substrate material using etching technique.

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The value of should not be too large; otherwise, the amplitude distribution of the current will change dramatically. After selecting, beam broadening factor and current amplitude distribution of each radiating element can be calculated. Ratio of the main lobe level to the sidelobe level is dB. The normalized current values of all levels are shown in Table 1.

The proposed frequency reconfigurable antenna (https://yamamotonight-m.ru/hack/?patch=7955) is based on back-fed circular patch antenna with an arc-shaped slot (length of 30 mm and width of 2 mm) in the ground plane. The top circular patch and the arc-shaped slot on the ground plane of this arc-shaped slot patch antenna (https://yamamotonight-m.ru/hack/?patch=4396) are excited by the coaxial back feed to achieve antenna radiation. As shown in Figure 3, the radii and of this arc-shaped slot circular patch antenna are 40 mm for the operating frequency of 1/9 GHz without any lumped elements or biasing network. While, if a common rectangular slot with the same length of 30 mm and width of 2 mm in the ground plane is employed, longer radius of 60 mm is needed for the antenna to achieve the same operating frequency at 1/9 GHz. The radius is fixed as 15 mm in both cases. In other words, the proposed antenna has the advantage of compact size and about 55/6% area reduction is achieved compared to the common rectangular slot antenna. Moreover, the operating frequency of this arc-shaped slot circular patch antenna can be directly adjusted by tuning the radius. As shown in Figure 4, the resonant frequency decreases from 2/19 GHz to 1/72 GHz as increases from 13 mm to 17 mm while keeping other dimension fixed. This implies that, for a given operating frequency, further antenna size reduction can be easily realized by reducing while properly increasing. Besides, using higher permittivity material substrate will also contribute to the antenna miniaturization.

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Design of Conformal Arrays

The geometry of the linear antenna (linked here) array is shown in Figure 1. Antenna patches (https://yamamotonight-m.ru/hack/?patch=8551) and the CPW-slot feeding network are, respectively, placed on the opposite sides of the substrate. Ring-shaped slotline structures with transverse end slots are used to connect with and feed the patches.

The 2D domain is considered in this work for the imaging of cracks on the bricks cross section. The 2D domain is considered in this work for the imaging of cracks on the bricks’ cross section because it saves memory space optimally and demands less tasking compared to 3D domain that is computationally time demanding. The imaging space is made up of rectangular block placed at the center of the domain surrounded on every side by transceiver points numbered from 1 to 16 to give full-view scanning of the brick phantom. The brick phantom without crack in which the dielectric properties are known (homogeneous material) is used as the background for the imaging domain. As a result of this, each sensor sends UWB pulse signals to the domain and other sensors now serve as observation points with each of them recording the received signal as the resulting response from the field.

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The back feeding port is located in the symmetry axis and 7 mm away from the center of the circular patch. Based on the circular shape of the substrate and the radiation patch, the slot in the ground is designed into an arc-shaped slot to reduce the size and realize better rotational symmetry of the ground plane. The total length of the arc-shaped slot is about 30 mm, and the width of the slot is 2 mm. Five PIN diodes as switches are symmetrically located in the slot by 20°, 32°, 90°, 148°, and 160°, respectively. Meanwhile, as shown in the bottom view of the proposed antenna, the ground plane is divided into six isolated parts by small slots with a width of 0/3 mm to provide independent DC biasing for PIN diodes. And three capacitors with the capacitance of 47 pF are mounted on each slot to provide RF and microwave continuity for the whole antenna ground plane. BAR-64-02 PIN diodes are mounted on the arc-shaped slot in ground plane to achieve frequency reconfiguration .

The geometry of the proposed antenna is illustrated in Figure 1. The antenna is fabricated on fire retardant dielectric substrate (FR4) having a relative permittivity of εr = 4/4 and dielectric loss tangent of ζ = 0/02. In order to have low profile thickness, the substrate is chosen to have a thickness of 1/6 mm. A rhombus-shaped slot is etched in the radiating element in order to excite two orthogonal modes. This perturbs the surface current over the patch element, thereby generating circular polarization. The orientation of the slot determines the nature of polarization. The antenna is fed by 50 Ω SMA connector. A quarter wave transformer having an impedance of 50 Ω is used for impedance matching.

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Compact circular polarized patch antennas play a vital role in satellite communications and airborne communication due to their low profile and lightweight. These antennas require low cross-polarization isolation in order to mitigate multipath interference and wider axial ratio beamwidth to provide a wide coverage area. However, 3 dB axial ratio beamwidth of the antenna suffers from a narrow beamwidth and cannot meet the required practical applications. A lot of researchers have been proposed to improve axial ratio beamwidth and to reduce cross-polarization isolation. One way of improving the beamwidth is to employ a 3D ground structure as in [1, 2]. These structures utilize a multilayer stacked structure which diffracts the electromagnetic waves from the ground plane, thereby altering the radiation pattern of the antenna. However, these structures increase the overall width of the antenna. In , the beamwidth of the antenna is improved by altering the spacing between the two crossed dipoles placed in a square-shaped contour. However, it results in a bidirectional radiation pattern and thus results in power loss in the undesired direction. Another way of improving the beamwidth is by exciting surface waves through substrates extended on the ground plane as given in . This technique significantly produces backward radiations, thereby interfering with other circuit elements.

The center frequency of the design is 35 GHz, and the dielectric substrate with relative dielectric constant is selected. Thickness of the substrate is 0/5 mm. According to the design of the radiation unit, the size of the microstrip patch antenna is only about 3 mm. The curvature of 60 mm cylindrical diameter is smaller than the microstrip patch antenna. So the antenna can be regarded as a planar antenna and analyzed by the theory of planar antenna. The design needs to achieve a specific beam direction, which is 60° to the conformal vector axis, and can be realized by conformal array. According to the analysis of the series-feed array, the microstrip patch antenna can be composed of a series-feed array to achieve such a beam direction. It can be realized by adjusting the spacing between the elements. The low sidelobe can be realized by the Taylor synthesis method. The distribution current of the antenna array is tapered to reduce the sidelobe level.

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The gain measurement is performed by comparing to a standard horn antenna. The gain of the antenna is 12/2 dB.

5G MIMO Conformal Microstrip Antenna Design

From the first experimental result, it can be concluded that the reconstructed image from the measurement as displayed in Figure 3(b) matches the image from the simulation. The 5 mm hole in the brick had been clearly detected.

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Design of Rhombus-Shaped Slot Patch Antenna for Wireless Communications

In this design, the line width of the microstrip line is 0/46 mm, and the characteristic impedance is 50 Ω. Therefore, the input impedance of the patch element needs to be close to 50 Ω. Figure 3 is the input impedance of rectangular microstrip patch antenna. From the figure, the input impedance is about 50/34 Ω, which matches well to the characteristic impedance of the microstrip line.

Many buildings and civil structures are made up of reinforced concretes or cement based materials. These structures are designed to carry certain amount of load under certain conditions and for a specific period. Environmental exposure and loadings are ways through which deterioration and damage are introduced inside a functioning civil structure or cement based materials during service. For example, a structure can deteriorate when it is loaded with more than what it has been originally designed for. This gradual deterioration and damage to the material usually appear in the form of a crack or other anomalies. The anomaly presents a great threat to any civil structures; it is very dangerous and has caused a lot of destruction and damage. Even small cracks that look insignificant can grow and may eventually lead to severe structural failure. Whatever may be the genesis of these cracks, either being micro or macro in nature, the side effects of such a defect affect not only the structural properties of such buildings but also more importantly their mechanical behaviour, integrity, and permeability characteristics [1–4]. Therefore, when cracks occur, the actual strength of such structures would be reduced.

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2. 5G MIMO Conformal Antenna Design

Besides manual inspection that is ineffective and time-consuming, several nondestructive evaluation techniques have been used for crack detection such as ultrasonic technique, vibration technique, and strain-based technique; however, some of the sensors used either are too large in size or suffer from poor resolution . A high resolution microwave imaging technique with ultrawideband signal in detecting cracks of millimeter scale is proposed.

From the simulation and experimental results of various anomaly scenarios, it could be concluded that microwave imaging technique has a high potential to be applied to defect detection of cement based materials. The achieved resolution of enables detection of cracks as small as 5 mm in size. Such a resolution enables detection of crack at the early stage of development.

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Receiver Shure LX4 Service Manual

In this paper, we designed a hexa shape patch antenna for L-band & S-band application. After designing the antenna on 1/8GHz (L-band) and 2/5GHz (S-band) frequency, we study and analysed the results for both bands using ie3d software.

Three kinds of arrays are given in this design. The first two arrays actually provide reference for the Taylor distribution matrix. The first array provides an appropriate spacing of the radiating elements. The second one determines the length of the serpentine. The final array form is based on the two arrays to adjust the radiation side of each radiating element to realize the current redistribution. In the array of rectangular patch, the gain is higher in the form of uniform distribution with intermediate feed. The lowest sidelobe level is the Taylor distribution with intermediate feed to reduce the sidelobe. The narrowest beam and the best matched impedance are the uniform distribution with one end of the feed. It can be seen that the reduction of the first sidelobe level is at the expense of width of the main lobe.

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The rectangular microstrip antenna element is shown in Figure 1. and of the patch element are adjusted during the simulation process. The size of mainly affects the resonant frequency, and mainly affects impedance matching.

This paper presents an optimized inset-fed rectangular microstrip patch antenna (see page) for WIMAX (3/5 GHz) applications. The bandwidth (BW) of a microstrip patch antenna is narrow which limits its operation in wireless communication. The bandwidth can be improved by symmetrically cutting a double I-shaped slot of size 2 mm x 10 mm from the patch, and U-shaped (https://yamamotonight-m.ru/hack/?patch=3144) slot of size 2 mm x 22 mm from the ground with reference to the edges of the patch.

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Cracks in concrete or cement based materials present a great threat to any civil structures; they are very dangerous and have caused a lot of destruction and damage. Even small cracks that look insignificant can grow and may eventually lead to severe structural failure. Besides manual inspection that is ineffective and time-consuming, several nondestructive evaluation techniques have been used for crack detection such as ultrasonic technique, vibration technique, and strain-based technique; however, some of the sensors used are either too large in size or limited in resolution. A high resolution microwave imaging technique with ultrawideband signal for crack detection in concrete structures is proposed. A combination of the delay-and-sum beamformer with full-view mounted antennas constitutes the image reconstruction algorithm. Various anomaly scenarios in cement bricks were simulated using FDTD, constructed, and measured in the lab.

A smart antenna for mobile applications incorporating an array of ± 450 polarised stacked patch elements 4 columns wide excited by a multi-beamforming and beam shaping network is described. Four narrow overlapping beams, one wide “broadcast channel” beam and right and left shaped beams can be provided. The later shaped beams are to provide high capacity coverage in a specific narrow angular sector while low capacity coverage is maintained over the remainder of a 1200 sector. Results are presented for the simulation of this smart antenna using CST EM simulation software. In addition, a demonstrator array has been constructed and tested which has yielded a positive conformation of the simulation results. It will be shown that the effects of mutual coupling degrade the beam shapes, particularly for the broadcast beam producing a significant reduction in gain over the centre of the pattern. Results are included to show the effects of applying modified complex excitation weights for compensation of mutual coupling. Whilst this technique can be shown to restore beam patterns it is also shown to introduce unacceptably high return loss at the antenna input ports. An alternative technique for producing Wide Angle Impedance Matching (WAIM) is described which is shown to improve return loss but degrade beam shapes. This work describes how both techniques can be combined to maintain good beam shapes and preserve good impedance matching, with consequent good return loss, over wide scan angles and also for shaped beams.

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The preferred models for the analysis of Microstrip patch antennas are the transmission line model, cavity model, and full wave model (which include primarily integral equations/Moment Method). The transmission line model is the simplest of all and it gives good physical insight but it is less accurate. The cavity model is more accurate and gives good physical insight but is complex in nature. The full wave models are extremely accurate, versatile and can treat single elements, finite and infinite arrays, stacked elements, arbitrary shaped elements and coupling. These give less insight as compared to the two models mentioned above and are far more complex in nature.

In this paper, 4 pairs of microstrip MIMO conformal antennas of 35 GHz have been designed

This paper presents the design of a MIMO conformal antenna for 5G. The frequency is 35 GHz, the carrier of conformal is a cylinder, and the angle between the main lobe of pattern and the carrier axis is 60°. The sidelobe characteristics of the antenna significantly affect the interference of the system and the suppression of the clutter. The antenna designed in this paper requires the first sidelobe level to be about −18 dB. In view of this characteristic, a series-fed standing wave antenna array with Taylor distribution is designed. Considering the influence of coupling, 4 pairs of antennas are designed. The results of the research are well suited for the 5G MIMO communication.

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In this paper, we present the results using the proposed technique for cement based bricks. A total of 16 antennas were mounted surrounding the material producing a full-view configuration.

In recent years, due to the breakthroughs of modern wireless communications, for example, near field communications (NFC), radio frequency identifications (RFID), and the internet of things (IoT), the developments of miniaturized and multiband/multimode communication components have been the main barriers in such science and engineering areas. The first component, for instance, used to send/receive the electromagnetic wave signals should be the antenna component, and comprehensive researches have focused on the multiband antennas and/or ultrawideband antennas, for the miniaturization and multiband/multimode requirements. In the various kinds of reported multiband antennas, monopole antenna is one of the most attractive configurations in recent years, because of the compact sizes, flexible designs, low fabrication costs, and well radiation characteristics. Some of the monopole antenna configurations are, for example, circular/rectangular/spiral ring patch antenna [1–3], I-shaped/U-shaped slot defected and T-shaped slot defected planar antenna , and spirograph planar antenna . These multiband monopole antennas were achieved by properly designing various resonator configurations to reduce operating frequencies, improve radiation pattern, and at the same time reduce cross-polarization characteristics. However, most of these antennas have complex configurations.

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Based on (2), the higher is the higher can be achieved; however, the maximum frequency is not unlimited due to higher signal reflection and attenuation inside the material at high frequencies. After several tests we found out that optimum is from 1 GHz to 7 GHz. Using this frequency bandwidth together with 16 antennas in multistatic configuration, can be achieved as shown in later section.

The geometry of the proposed dual-polarized patch antenna is shown in Figure 6. It consists of five substrates: the upper horizontal substrate (#1), the middle vertical substrates (#2 and #3), and the bottom horizontal substrates (#4 and #5). The radiating circular patch is printed on one of the horizontal substrates (#1). The four shaped strips are printed on the vertical substrates (#2 and #3) and soldered to Ports 3–6 of the hybrid ring feeding network via four probes. The quarter-wavelength impedance transformer and differential feeding line of Port 2 and the quarter-wavelength impedance transformer of Port 1 are printed on the top layer of the horizontal substrate (#4), and the hybrid ring with the differential feeding line of Port 1 is printed on the bottom layer of the horizontal substrate (#5). The ground is between the two horizontal substrates (#4 and #5). The height of the air layer between vertical substrates #2 and #3 is 18 mm. This air layer is designed to widen the working band.

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The second part of MIMO conformal antenna design is the microstrip series-fed array. To get high gain, low sidelobe, beam scanning, and beam control, we need to use the discrete radiating element to form the array according to the appropriate excitation and distance. In this paper, the requirements of the microstrip array are as follows: the gain is 10 dB, the angle between the main lobe and plane of array is not less than 10% ( dB), and the first sidelobe level is about −18 dB. The design of microstrip is divided into three steps. The first step is to select the feed method of the linear array, the second step is to realize the offset of the main lobe, and third step is to reduce the first sidelobe level.

In this paper, a dual-polarized patch antenna fed by a hybrid ring structure is proposed. The proposed antenna adopts shape strips coupled feeding structure to achieve wide working band. And a novel hybrid ring is applied as a feeding network. The hybrid ring feeding network has a broadband high isolation characteristic.

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The form of the array is the same as that of the middle feed, and there is a difference in the size of the array. The size of the array element is designed according to Taylor current distribution regulation of the elements at all levels which can be obtained from Table 2. By adjusting the radiation edge size of each element, the radiation admittance of each element can be changed, and the corresponding value of the radiation edge size can be obtained.