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In recent years, improvements in wireless communication have led to the development of microstrip or patch antennas. The article discusses using simulation, measurement, an RLC equivalent circuit model, and machine learning to assess antenna performance. The antenna's dimensions are 1.01 λ0×0.612λ0 with respect to the lowest operating frequency, the maximum achieved gain is 6.76 dB, the maximum directivity is 8.21 dBi, and the maximum efficiency is 83.05%. The prototype's measured return loss is compared to CST and ADS simulations. The prediction of gain and directivity of the antenna is determined using a different supervised regression machine learning (ML) method. The performance of ML models is measured by the variance score, R square, mean square error (MSE), mean absolute error (MAE), root mean square error (RMSE), and mean squared logarithmic error (MSLE), etc. With errors of less than unity and an accuracy of roughly 98%, Ridge regression gain prediction outperforms the other seven ML models. Gaussian process regression is the best method for predicting directivity. Finally, modeling results from CST and ADS, as well as measured and anticipated results from machine learning, reveal that the suggested antenna is a good candidate for LTE.

In recent years, improvements in wireless communication have led to the development of microstrip or patch antennas. The article discusses using simulation, measurement, an RLC equivalent circuit model, and machine learning to assess antenna performance. The antenna's dimensions are 1.01 λ 0 × 0.612 λ 0 with respect to the lowest operating frequency, the maximum achieved gain is 6.76 dB, the maximum directivity is 8.21 dBi, and the maximum efficiency is 83.05%. The prototype's measured return loss is compared to CST and ADS simulations. The prediction of gain and directivity of the antenna is determined using a different supervised regression machine learning (ML) method. The performance of ML models is measured by the variance score, R square, mean square error (MSE), mean absolute error (MAE), root mean square error (RMSE), and mean squared logarithmic error (MSLE), etc. With errors of less than unity and an accuracy of roughly 98%, Ridge regression gain prediction outperforms the other seven ML models. Gaussian process regression is the best method for predicting directivity. Finally, modeling results from CST and ADS, as well as measured and anticipated results from machine learning, reveal that the suggested antenna is a good candidate for LTE. [ABSTRACT FROM AUTHOR]

In this paper, Yagi antennas are introduced into microwave transmission measuring instruments as the transmit and receive antennas for detecting moisture content in oil-water mixtures. A Yagi antenna is designed, where the simulation results show a peak gain of 9 dBi and the reflection coefficient S11 is lower than -10 dB in a frequency band of 2.25-4 GHz. Meanwhile, the measurement result using a vector network analyser shows that the Yagi antenna works in the frequency band of 2.9-4.15 GHz, indicating that measurement results shifted to high frequencies. Based on the Yagi antennas, a moisture content measuring system using the microwave transmission method is designed and constructed, where the measurement results show the Yagi directional high-gain microwave antenna used in this paper can achieve water holdup measurement in the range of 0-100%, where the relative error is less than ±15% and the absolute error is within ±2.341%. [ABSTRACT FROM AUTHOR]

A novel end-fire wide-scanning metasurface antenna array for a millimeter wave operating at 28 GHz is proposed in this paper. The suggested antenna is considered as a low-cost device since it is printed on both sides of a single-layer FR-4 substrate with a thickness of 0.5 mm and a size of 44×13 mm2. On the top side of the cell phone PCB, eight Yagi antenna elements fed by microstrip lines have been used to form a linear array. The antenna gain and impedance matching are increased by placing a 5×5 metasurface composed of metallic H-shapes right in front of the Yagi array. This technique achieves a large bandwidth of 3.5 GHz from 26.2 to 29.7 GHz, and a high gain of 15.5 dBi, which is almost stable over a wide scanning angle. Finally, in order to understand the integration impact, the proposed antenna phased array has been covered by a casing. The simulation result demonstrates that there is no degradation effect for the entire assembly. [ABSTRACT FROM AUTHOR]

A miniaturized three split ring-like Multiple-Input Multiple-Output (MIMO) antenna is presented for the S and X frequency band applications. The proposed antenna has been numerically investigated at operating frequency 1-15 gigahertz (GHz). The MIMO antenna is analyzed, and its prototype is measured in five types of structure to identify the effect of the split ring and other physical conditions. This antenna is fabricated on the FR- 4 substrates with a dimension of 25 mm × 40 mm which will provide the miniaturization factor of λ/2. The high gain of 6.61 dBi and an ultrawideband of 3.25 GHz is achieved by using split-ring resonators (SRRs) in the proposed miniaturized MIMO antenna structure. We have also analyzed the effect of the split rings on the overall radiation band and return loss on the S and X frequency band. Furthermore, the prototype measurement confirms the suggested antenna radiation characteristics. [ABSTRACT FROM AUTHOR]

A compact fully metallic antenna with high endfire gain and vertical polarization is presented for applications that require the antenna to be mounted on large metallic platforms. The proposed structure includes one driven element on a ground plane, in addition to several parasitic directors and reflectors. The antenna behaves like a Yagi array, but with vertical polarization, where multiple directors and reflectors are used to enhance the endfire gain in the plane that contains the ground surface. The driven element is an upside-down U-shaped metallic strip with short vertical sides connected to the ground plane. The radiation is predominantly emitted from these vertical sides giving the antenna its vertical polarization radiation. Directors and reflectors are designed based on the driven element, with directors having the center of the U-shaped strip connected to the ground plane and reflectors without shorting pins in the middle. A prototype is fabricated with a volume of 104 $\times 55\times $ 6 mm3. The measured bandwidth is 18% (5.32–6.38 GHz). The variation of endfire gain is 2 dB around the nominal gain of 10.3 dBi across the bandwidth. [ABSTRACT FROM AUTHOR]

We present a quasi-Yagi antenna mounted on a periodic surface for a wearable UHF RFID reader operating in the UHF RFID frequency band centered at 915 MHz. The periodic surface was co-optimized with the antenna to enhance the launching of surface waves to enable the end-fire radiation along the forearm so that a user can identify objects by pointing her/his hand towards them. In addition to the radiation pattern modification, the ground plane of the periodic surface serves the second purpose of isolating the antenna from the human body. We optimized the antenna in a full-wave EM simulator using a simplified cylindrical model of the forearm and in the simulation, it achieved the end-fire directivity of 5.9 dBi along the forearm. In the wireless testing, the quasi-Yagi antenna provided the read range of 3.8 m for a typical UHF RFID tag having 0 dBi gain when the reader’s output power was 32 dBm that corresponds with EIRP =0.56 W and SAR =0.191 W/kg in our simulations. Considering both, the RFID emission regulations with EIRP = 3.28 W or 4 W and the SAR limit of 1.6 W/kg averaged over 1 gram of tissue, the read range could be further enhanced for reader units with higher output power.

The design of the dual-band Yagi antenna was developed to support voice communication through voice repeaters on microsatellites in the UHF-VHV frequency from ground stations. The Yagi antenna is a type of half lambda dipole antenna that makes it easy to obtain direction and increase gain. The antenna is designed using the method of moment through a simulation with the CST microwave studio software application. The design used as an antenna element material is a type of copper pipe cylinder. The results of the Yagi antenna design in the VHF frequency consist of one driven element, one reflector element, and three director elements, while the UHF frequency consists of one reflector element and seven directors. The results of simulation parameters are obtained, such as Bandwidth of return loss below 10 dB is 4.3 MHz (VHF), and 44 MHz (UHF), VSWR (2:1) is 1.24 (VHF) and 1.36 (UHF), Gain is 9.19 dBi (VHF) and 10.5 dBi (UHF) and Beam Width is 64 degree (VHF) and 58 degree (UHF). The suitability of the antenna design target is dual-band, and Gain value in UHF is higher than VHF.

A compact receiving (Rx) antenna integration for 3D direction-finding passive radar is proposed. The proposed antenna integration consists of two Yagi antennas and two waveguide slot antennas. The antennas are mounted on four sides of a parallelepiped polycarbonate module with the same type of antennas facing each other on the opposite sides of the module. The antenna is designed for a direction-finding radar system as an Rx terminal on an avionic vehicle with a separate Tx base station on the ground. The proposed antenna integration demonstrates a maximum return loss of 9.6 dB (voltage standing wave ratio 2:1) ranging from 9.7 to 10.2 GHz in the X band and has suitable radiation patterns for direction-finding system in both the xz and yz planes. In addition, the proposed antenna integration has the compact size and light gross weight of 37 mm × 46 mm × 50 mm and 97 g, respectively, making it suitable for application in an avionic system.

A high-selectivity low-profile filtering end-fire antenna is proposed using a bandstop filtering (BSF) element integrated into the feedline of the conventional quasi-Yagi antenna. Three transmission zeros (TZs) and six transmission poles (TPs) of the BSF element can be obtained through the odd–even mode equivalent circuit analysis and calculation. With the help of TP and TZ of the BSF element, an additional resonant mode within the operating band and additional radiation null at the upper band edge of the antenna can be obtained, respectively. Consequently, the impedance bandwidth and frequency selectivity of the proposed antenna can be improved compared with the conventional quasi-Yagi antenna. For demonstration, an antenna is fabricated whose measured results exhibit a stable end-fire gain response with two radiation nulls close to two sides of the operation band.

Two novel designs of dual-mode beam-steerable array antennas are proposed for customer-premises equipment applications. To obtain the optimal distribution of excitations for the arrays, the gain and front-back ratio of the array systems are optimized by using the method of maximum power transmission efficiency. The first design operates at 2.45 GHz and uses four folded monopoles of height

In this paper, a single null compensation dipole antenna for Wi‐Fi band (2.4 GHz) is developed. The antenna is fed by the parallel transmission lines, and its radiation unit consists of a printed dipole antenna and a Yagi antenna. The proposed antenna has three layers. The top and bottom layers are printed with the dipole antenna and the driver arm of the Yagi antenna. The director and the reflector of the Yagi antenna are placed on the middle layer. The three layers are separated by two FR‐4 substrates. This antenna satisfies the omnidirectional radiation characteristic in its H plane and can compensate a null point in the E plane. Simulation results show that the 10 dB bandwidth is 2.32 to 2.46 GHz. The maximum realized gain is 1.13 dB in the frequency band. The non‐roundness of the H plane is less than 2 dB, which shows good omni‐directivity. A null point in the radiation pattern of the E plane is compensated to −1.4 dB at 2.4 GHz, while the other null point of the E plane remains below −15 dB. The antenna has been manufactured and tested, and the measurement results validate the design and the simulation results. [ABSTRACT FROM AUTHOR]

An antenna array composed of four inclined microstrip Yagi antennas is proposed for a direction finding (DF) system operated in L band. Each element antenna is designed to have a tilted beam toward a central array axis in order to have high gain in the boresight axis of the antenna array. In comparison to a patch antenna array, having the same structure, antenna array gain is improved by a 2.3 dB maximum around the array axis, monopulse slope is increased by 72% and the linearity of the slope is improved significantly. Also, axial ratio is improved by 3 dB max within ±25° from boresight. [ABSTRACT FROM AUTHOR]

This article presents a polarization-reconfigurable wideband high-gain antenna based on liquid metal tuning. The antenna consists of a center-feed circular patch antenna with a C-shaped slot as the driven element. To broaden the bandwidth and improve the realized gain, a parasitic circular disc and 13 circular directors are employed. The direction of polarization can be tuned by changing the location of the liquid metal alloy contained in the tube. The relationship between the dimensions and the maximally achievable gain has been analyzed. The antenna has exhibited a −10 dB impedance bandwidth from 4.3 to 5.3 GHz (a fractional bandwidth of 21.2%). A 14.4 dBi gain is achieved at 5.3 GHz. The simulation and measurement results show good agreement with each other. [ABSTRACT FROM AUTHOR]

Antennas which are one of the most important components that designate the system characteristic in radar systems, nowadays have a substantial position in military as well as civil areas. Due to their narrow beamwidth and high gain radiation reflector antennas are frequently preferred in radar systems. High gain and low sidelobe/backlobe levels are one of the most significant parameters in reflector antenna design. Sidelobes in radiation patterns cause the energy to radiate in undesirable directions. In this study, parabolic reflector antenna design with low near sidelobe and backlobe levels on horizontal/vertical planes and its performance analysis are presented. For this purpose, three element Yagi array fed parabolic reflector antenna with suppressed near sidelobes and backlobes by novel shroud and strips is designed. Thus, for the proposed reflector antenna; a gain of 24,5 dB, sidelobe level of -26 dB and 28,8 dB respectively on horizontal and vertical plane, backlobe level of -42,3 dB and half power beamwidth of 10° on 1100-1200 MHz frequency band are achieved. It is shown that our design fulfills the ETSI Class-2 standards. Design, analysis and optimization studies are performed on CST program.

In this paper a small copter size unmanned aerial Vehicle (UAV) has been designed as a platform for a flying computer station to carry out cyber-attacks (Jamming, Spoofing, Man in the Middle, etc.) on devices that utilize wireless technologies, WiFi in particular. A yagi-patch hybrid antenna designed for 2.4 GHz freely rotates on two axes, thus allowing the drone to perform attacks on low power devices up to ranges of 300 meters. The modular design of the UAV allows for quick swapping of modules depending on the specific wireless technology used by the target device. [ABSTRACT FROM AUTHOR]

This letter proposes a rotated stacked Yagi antenna with high directivity and circular polarization. The proposed antenna consists of three elements with a rotation angle and different lengths: a director, a reflector, and a driven element connected to the coaxial feeder. The coaxial feeding is connected to the driven element of the proposed antenna via a LC-balun, and the others are coupled with the driven element. Each stacked element with different lengths is equally rotated at an angle of 60° with respect to the lower element so that the dipole array antenna forms a high directive circular polarization. The size of the proposed antenna is 0.49γ0 × 0.49γ0 × 0.17γ0 at 2.45 GHz and achieved a 10 dB impedance bandwidth of 6.3%, a 3 dB axial ratio bandwidth of 8%, and a peak gain of 4.3 dBic. [ABSTRACT FROM AUTHOR]

A novel end‐fire circularly polarized (CP) antenna is presented by integrating a vertically polarized magnetic Yagi array, a horizontally polarized electric Yagi array, various lengths of the directors and common driven elements. Slots with nine Jesus crosses are etched on the common driven elements to extend the impedance matching bandwidth of magnetic Yagi array, while various length of directors are employed to obtain wide axial ratio (AR) bandwidth. The designed CP antenna is both numerically and experimentally validated, and experimental results agree well with electromagnetic simulated results. The fractional impedance bandwidth for ∣S11∣ < 10 dB is up to 20.7%, and AR bandwidth of less than 3 dB is up to 16.0% in fraction. [ABSTRACT FROM AUTHOR]

A novel wideband high-gain antenna array with filtering response is presented. The proposed array consists of four Yagi antenna elements and one feeding network, which could realize signal filtering, power splitting as well as impedance transforming characteristics simultaneously. The operating mechanism is analyzed and the detailed design procedure is presented. For demonstration, a 2 × 2 array is designed at the center frequency of 3.0 GHz with the measured fractional bandwidth of 73.3%. Measured in-band maximum gain is 13.2 dB, whereas the out-of-band suppression level is better than 23.2 dB. Compared with the conventional array, the proposed filtering array shows high suppression in the stopband, good selectivity at passband edges and flat antenna gain in the passband. Simulated and measured results provide a good verification for the theoretical concepts. [ABSTRACT FROM AUTHOR]

With the wide use of AIS system in the world, especially in ports and the waters with heavy traffic, AIS message loss may be related to environmental conditions, obstacle, limitation of VHF technology and AIS network overload, thereby reducing the AIS signal successful reception rate. This paper selected typical AIS data received by Yagi and Omni antennas at the same time in specific waters, uses grid and AIS data recovery technology, establishes the AIS signal coverage model, analyzes signal reception rate of Yagi antenna and Omni antenna of AIS base station, and verified the superiority of Yagi antenna in AIS signal reception rate.

In this paper, a frequency reconfigurable quasi-Yagi dipole antenna is proposed by leveraging the properties of microfluidic technology. The proposed antenna comprises a metal-printed driven dipole element and three directors. To tune resonant frequencies, microfluidic channels are integrated into the driven element. To maintain a high gain for all the tuned frequencies, microfluidic channels are also integrated into the directors. Therefore, the length of the driven-element as well as directors can be controlled by injecting liquid metal in the microfluidic channels. The proposed antenna has the capability of tuning the frequency by varying the length of the metal-filled channels, while maintaining a high gain for all the tuned frequencies. The proposed antenna’s performance is experimentally demonstrated after fabrication. The injected amount of liquid metal into the microfluidic channels is controlled using programmable pneumatic micropumps. The prototype exhibits continuous tuning of the resonant frequencies from 1.8 GHz to 2.4 GHz; the measured peak gain of the proposed antenna is varied in the range of 8 dBi to 8.5 dBi. Therefore, continuous tuning with high gain is successfully demonstrated using liquid-metal-filled microfluidic channels. [ABSTRACT FROM AUTHOR]

Abstract: In this article, a multiband Yagi‐Uda antenna is developed based on a driver stack configuration, providing the required bands without modifying significantly the parameters of a conventional one. The design and construction are very easy in comparison to other similar configurations. The resonances are derived from each driver used in the configuration, which are excited simultaneously without any complex feeding network. The reflector and directors are proposed according to the largest and shortest driver, respectively, in order to preserve the directive radiation pattern as well as the gain compared to a conventional Yagi‐Uda antenna. In this case, the device is designed to perform at 600, 900, and 1900 MHz, achieving an average gain of 4.5 dBi, and a front‐to‐back lobe ratio of 10 dB by using just one director. [ABSTRACT FROM AUTHOR]

An electronically controlled plasma reflector antenna array is presented in term of Yagi antenna technology and plasma theory in this paper. The array comprised of a plasma symmetrical dipole in the center and 6 plasma column antennas uniformly around the dipole. When only the active plasma dipole and one of passive columns are energized, they perform like conductive metals capable to radiate radio signal like a two-element plasma Yagi antenna. Pattern reconfigurability of the antenna array can be achieved by sequentially exciting one of 6 plasma columns, and the plasma antenna array also produces better gain through increasing the number of plasma reflectors. Due to the adoption of equal amplitude and phase feeding technology, it greatly reduces the technical difficulty of the implementation of pattern reconfigurability. On the other hand, if all of plasma columns are off, there is only minor reflection from dielectric tubes, and hence, the plasma antenna array has stealth performance. [ABSTRACT FROM AUTHOR]

Abstract: A planar Rotman lens antenna that generates multiple beams is presented over a wide angular range. The proposed multi‐beam antenna consists of a Rotman lens and a ten‐element printed Yagi antenna array. By properly comparing optical aberrations, expressing as the normalized path length errors Δl, the suitable ratio of on‐axis to off‐axis focal length (g = G/F) is acquired so as to minimize phase errors for the array elements. Ten dummy ports are employed to reduce the performance deterioration caused by energy reflection. A prototype with seven input ports was fabricated and measured, covering a wide scanning angle of 60° (–30°, 30°). The measured beam patterns show that the seven beam gains are distributed from 11.9 to 13.6 dBi under operating of 8.15 GHz. Both the simulated and measured results are used to verify the design approach. [ABSTRACT FROM AUTHOR]

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In the paper, wideband antenna arrays aimed at microwave imaging applications and SAR applications operating at Ka band were designed. The antenna array feeding network is realized by a low-loss SIW technology. Moreover, we have replaced the large feed network comprised of various T and Y junctions by a simple broadband network of compact size to more reduce losses in the substrate integrated waveguide and also save space on the PCB. The designed power 8-way divider is complemented by a wideband substrate integrated waveguide to a grounded coplanar waveguide transition and directly connected to the antenna elements. The measured results of antenna array are consistent with our simulation. Obtained results of the developed array demonstrated improvement compared to previously developed binary feed networks with microstrip or SIW splitters.

In this paper, a full solid angle scanning cylindrical-and-conical (CYLCON) conformal phased array antenna (PAA) is designed. First, a microstrip Yagi antenna with low profile and small size is proposed and discussed. Second, a cylindrical conformal Yagi antenna array consisting of 24 aforementioned 8-element Yagi antennas is designed and optimized. Simulation results show that the Yagi antenna array can realize low-elevation beam scanning in the region of 0 ^\circ \le \theta \le 30 ^\circ , 30 ^\circ \le \varphi \le 150 ^\circ with low sidelobe levels and sharp beams. Third, CYLCON conformal microstrip antenna arrays are developed to realize the broadside beam scanning. Afterwards, an integrated PAA by combining the aforementioned conformal arrays along with feeding networks is constructed to achieve full solid angle scanning. Finally, a prototype is fabricated, the measured results show that it can realize beam scanning in the regions of 0 ^\circ \le \theta \le 30 ^\circ , 30 ^\circ \le \varphi \le 150 ^\circ , and 30 ^\circ \le \theta \le 180 ^\circ , 60 ^\circ \le \varphi \le 120 ^\circ , which meet well with those of the simulated. By arranging proper number of arrays along the perimeter accompanied with the switchable feeding configurations, a full solid angle scanning can be achieved. [ABSTRACT FROM AUTHOR]

Antennas are an important part in the microwave and THz systems for the enhancement of the radiation in various application such as medical imaging. Yagi antenna because of end fire radiation, wide bandwidth and high gain are attractive in THz detector, wireless communications and THz medical imaging. Therefore, in this article we have developed a Yagi antenna for 1 THz applications with high gain and in this antenna a graphene loop is added to dipole radiator and with variation in the graphene biasing, reconfigurable characteristic is obtained and the Q-factor is controlled in antenna. The CST microwave studio is used for modeling and simulation with FDTD solution. The antenna’s total size is 0.53λ × 0.73λ for 1 THz with the 1 μm thickness of the Silicon substrate. Finally, a novel model has been suggested for the implementation of graphene layer in PBG layer and by embedding a graphene pin in PBG layer a Fabry-Perot waveguide has been designed that improves the bandwidth and antenna gain simultaneously. Higher Q- factor, higher bandwidth with high gain pattern are the benefits of the novel structure that are important in THz systems. [ABSTRACT FROM AUTHOR]

In this paper, a frequency reconfigurable quasi-Yagi dipole antenna is proposed by leveraging the properties of microfluidic technology. The proposed antenna comprises a metal-printed driven dipole element and three directors. To tune resonant frequencies, microfluidic channels are integrated into the driven element. To maintain a high gain for all the tuned frequencies, microfluidic channels are also integrated into the directors. Therefore, the length of the driven-element as well as directors can be controlled by injecting liquid metal in the microfluidic channels. The proposed antenna has the capability of tuning the frequency by varying the length of the metal-filled channels, while maintaining a high gain for all the tuned frequencies. The proposed antenna’s performance is experimentally demonstrated after fabrication. The injected amount of liquid metal into the microfluidic channels is controlled using programmable pneumatic micropumps. The prototype exhibits continuous tuning of the resonant frequencies from 1.8 GHz to 2.4 GHz; the measured peak gain of the proposed antenna is varied in the range of 8 dBi to 8.5 dBi. Therefore, continuous tuning with high gain is successfully demonstrated using liquid-metal-filled microfluidic channels.

In the paper, a novel instance of the real-coding genetic algorithm (RCGA), called the Mean-adaptive real-coding genetic algorithm (MAD-RCGA), is applied along with other RCGAs, to selected problems in microwaves. The problems include the design of a microstrip dipole, the design of frequency-selective surfaces, and the design of a Yagi antenna. Apart from other things, the purpose of this paper is to compare these instances with MAD-RCGA on problems having some technical relevance.

In order to remotely monitor the activities of heartbeat, respiration and body movement, this article designed and implemented a single-channel nonorthogonal in-phase/quadrature (I/Q) RF sensor, which works at the central frequency of 2.4 GHz. The designed RF sensor is based on a printed circuit board (PCB) antenna. Taking into account low cost, simple structure and easy fabrication, the antenna is designed and implemented with a special broad-band microstrip-tocoplanar strip line Balun structure by combining the transmitter with the receiver on a PCB to form one single antenna system. The gain of the sensor is 7.7 dB. The return loss is -22.7 dB at 2.4 GHz and the directionality of the antenna is satisfactory for monitoring vital signs. It has been validated that the designed sensor can detect the respiration, heartbeat and body movement accurately in comparison with the signals acquired by respiration sensor and pulse sensor. [ABSTRACT FROM AUTHOR]

A top-hat monopole Yagi antenna is presented to produce an end-fire radiation beam. The antenna has an extremely low profile and wide operating bandwidth. It consists of a folded top-hat monopole as the driven element and four short-circuited top-hat monopoles as parasitic elements. A broad bandwidth can be achieved by adjusting the different resonances introduced by the driven and parasitic elements. A prototype operating at the UHF band (\mathbff_\mathbf0 = \mathbf550\;\mathbfMHz) is fabricated and tested. Measured results show that a fractional bandwidth (\vert\mathbfS\mathbf{11}\vert < - \mathbf{10}\;\mathbf{dB}) of 20.5% is obtained while the antenna height is only \mathbf\lambda _\mathbf0/\mathbf28 at the center frequency. [ABSTRACT FROM PUBLISHER]

Planar Yagi antennas are commonly hard to possess simple structure, high gain, and broad bandwidth at the same time. In this letter, a new substrate integrated waveguide (SIW)-fed Yagi antenna is proposed with nonplanar director element, and it achieves bandwidth of 25.7% and gain of 9.46 dBi at 10.0 GHz. Integrated of an SIW hybrid ring coupler, a Yagi monopulse antenna is designed.Measured gain of the sum pattern is higher than 13 dBi, whereas the maximum null depth of the difference pattern is lower than 20 dB in 9.4-10.05 GHz. This type of monopulse antenna presents an excellent candidate in directional-finding system. [ABSTRACT FROM AUTHOR]

This paper presents a first reported 60-GHz CMOS sub-harmonic RF receiver with an integrated on-chip artificial-magnetic-conductor (AMC) Yagi antenna and a balun bandpass filter (BPF) fabricated in 90-nm technology. The on-chip antenna with an AMC structure can reduce the substrate loss and increase the antenna radiation efficiency and power gain. The on-chip balun BPF combines the integrated design of the balun and RF BPF to reduce the circuit size and the insertion loss. The sub-harmonic receiver is adopted to mitigate the dc offset problem. The probe-station based on-wafer continuous wave wireless transmission test is conducted (R=1~\m) and the measured total receiving conversion gain CGant+Rx and output third-order intercept point of the integrated RF receiver (with the on-chip AMC antenna and the balun BPF) are 16.2 dB and 3 dBm at 60 GHz, respectively. In error vector magnitude/bit error rate (BER) tests, the measured maximum data rate is 1.152 Gb/s in the 16QAM mode at a 25-cm wireless link (transmitting EIRP=23~\dBm) approximately with a BER of \10^-3. The presented integrated RF receiver will be very useful for the design of a 60-GHz fully integrated CMOS single-chip radio for very-short-range communication applications. [ABSTRACT FROM AUTHOR]