466 results about "Broad bandwidth" patented technology

The invention discloses a broadband wide frequency spectrum analysis method and system based on deep learning. The method comprises the steps of spectrum signal acquisition, spectrum preprocessing, abnormal interference detection, spectrum trend prediction and spectrum scheduling management. The invention relates to the technical field of wide-frequency spectrum analysis, in particular to a broadband wide-frequency spectrum analysis method and system based on deep learning, which adopts a three-step method of abnormal interference detection, spectrum trend prediction and spectrum scheduling management, and adopts a layer-by-layer progressive deep learning and reinforcement learning technology. The real-time detection of spectrum abnormity, the accurate prediction of future trend and the optimal allocation of dynamic resources can be realized; carrying out abnormal interference detection by adopting a joint improvement multi-classification support vector machine method combined with feature enhancement; performing spectrum trend prediction by adopting a time sequence integrated network combined with one-dimensional convolution feature extraction; and performing spectrum scheduling management by adopting a reinforcement learning method enhanced by a near-end strategy optimization algorithm.

The invention discloses an ultra-wideband double-compensation type phase shifter, which comprises two one-to-two switches, and a reference state branch and a phase shift state branch which are connected between the two one-to-two switches, the reference state branch comprises a magnetic coupling inductor L1, a capacitor C2, a capacitor C3 and two compensation capacitors C1, the capacitor C2 is connected from the center of the magnetic coupling inductor L1 to the ground, and the capacitor C3 is connected from the center of the magnetic coupling inductor L1 to the ground. The capacitor C3 is connected with the magnetic coupling inductor L1 in parallel to form a magnetic coupling all-pass network, the two compensation capacitors C1 are symmetrically connected to the two sides of the magnetic coupling all-pass network in series, the phase shift state branch comprises an inductance type all-pass network and two compensation inductors L4, the inductance type all-pass network comprises an inductor L2, an inductor L3 and two capacitors C4, the inductor L3 is connected to the two capacitors C4 in series in parallel, and the compensation inductors L4 are connected to the two capacitors C4 in parallel. The inductor L2 is connected to the ground at the center of the two capacitors C4 connected in series, the two compensation inductors L4 are symmetrically connected to the two sides of the inductance type all-pass network in series, the compensation capacitors C1 and the compensation inductors L4 can compensate the phase, the phase frequency response change rate is slowed down, and phase shifting under the extremely wide bandwidth is achieved.

The invention provides a voltage stability control method for a multi-output switching power supply, which comprises the following steps of: sampling a main output channel in real time to obtain a voltage signal; the voltage signal is processed through a wide bandwidth error amplifier, a main channel adjusting signal is generated, and the main channel adjusting signal is used for driving a main power switch device; receiving an input voltage fluctuation frequency band of an auxiliary channel, a load current transient change gradient and a frequency spectrum coupling characteristic of a main channel adjusting signal through a dynamic prediction model, and generating an auxiliary channel adjusting signal with a phase lead compensation characteristic; a cross coupling active offset mechanism is constructed, time domain-frequency domain characteristics of coupling interference are extracted through a high-precision differential detection circuit, amplitude-frequency adjustable reverse correction signals are generated in real time through an adaptive compensation algorithm and injected into control nodes of an auxiliary output channel, and dynamic decoupling and ripple suppression are carried out. According to the method, high-stability control of multi-channel voltage under all working conditions is realized, and the dynamic response speed and the anti-interference capability are improved.

The invention discloses a method for estimating parameters of a ground phase-coded radar interference source based on an SAR image. The method comprises the steps of deriving a corresponding relation between phase-coded interference parameters and SAR image features and estimating the parameters. According to the method, the corresponding relation between the pulse width, the bandwidth, the carrier frequency and the repetition frequency of the interference signal and the interference characteristics on the SAR image is determined according to the mathematical relation, the problems of unclear mathematical expression, unclear parameter corresponding relation and the like on the phase coding radio frequency interference SAR image are solved, and the interference fringe parameters on the SAR image are estimated and the corresponding relation is obtained through derivation, so that the interference fringe parameters on the SAR image are estimated. And inversion of interference source parameters of the ground phase-coded radar is realized. Simulation results show that parameters such as pulse width, bandwidth, carrier frequency, repetition frequency and the like of phase coding radio frequency interference can be accurately estimated; the method can be applied to estimating parameters such as pulse width, bandwidth, carrier frequency, repetition frequency and the like of a phase-coded signal from an SAR image interfered by a ground same-frequency phase-coded radar signal.

The present disclosure provides an antenna, an antenna system and an automobile, belonging to the field of wireless communication technologies. The antenna includes a main antenna, a parasitic antenna and a main board; the main antenna and the parasitic antenna are both located on the surface of the main board, and the plane where the main antenna is located is parallel to the plane where the parasitic antenna is located and the positions are opposite; the feeding point of the main antenna is connected to the feeding transmission line of the main board, and the parasitic antenna is connected to the second grounding end of the main board; wherein, the difference between the resonant frequency point of the main antenna and the resonant frequency point of the parasitic antenna is less than a target threshold. When this antenna is applied in an automobile as a communication antenna of the automobile, such as a 4G communication antenna or a 5G communication antenna, it can achieve 4G or 5G wide-bandwidth coverage, such as full-bandwidth coverage. In addition, this antenna can also improve the out-of-band suppression ratio and enhance the anti-foreign frequency interference characteristics.

The invention provides a photonics beam domain receiving large-bandwidth blind source separation device and method for main lobe interference, and belongs to the technical field of wireless communication. The device comprises an optical domain multi-beam receiving module, an optical domain convolution mixing-instantaneous mixing conversion module and an optical domain instantaneous mixing blind source separation module. The optical domain multi-beam receiving module estimates an arrival angle of an antenna array element receiving signal, and the optical delay network constructs a plurality of receiving beams according to the arrival angle to realize synchronous receiving of a mixed signal; the variable optical delay array realizes delay synchronization of different receiving beams and completes conversion from optical domain convolution mixing to instantaneous mixing; and the optical domain instantaneous mixed blind source separation module completes extraction of a target signal through optical domain amplitude weighted iterative optimization. The photonics beam domain reception large-bandwidth blind source separation device and method have the advantages of being wide in working frequency band range, large in bandwidth and low in energy consumption, interference in a beam main lobe is effectively restrained, and the anti-interference capacity of a phased-array antenna is improved.

A low-profile ultra-wideband wide-angle scanning phased-array antenna based on a tight coupling structure is composed of a metal floor and a plurality of antenna units, the antenna units extend in the X polarization direction and the Y polarization direction respectively to form a plane of any size, and an antenna array is formed; the antenna unit sequentially comprises an upper substrate, a dipole antenna and a lower substrate from top to bottom, the dipole antenna is vertically and crossly placed and comprises two layers of dielectric substrates and a layer of prepreg between the two layers of dielectric substrates, and a resistor-coated pattern is printed on the upper surface of the lower substrate.

The invention discloses a broadband wide-angle scanning array antenna based on a metasurface lens, belongs to the technical field of phased-array antennas, solves the problem of how to improve the scanning range and gain of the phased-array antennae, and is characterized in that the metasurface lens with phase gradient is loaded above the phased-array antenna on the basis of not changing the structure of the original phased-array antenna. The beam scanning range of the phased-array antenna is expanded, and the performance such as gain is improved; according to the invention, an original phased-array antenna does not need to be modified and redesigned, additional active devices do not need to be added, new components do not need to be introduced into an original system, the system cost is effectively reduced, the system size is reduced, and the antenna is suitable for scenes, such as unmanned aerial vehicles and low-altitude aircrafts, which have strict requirements on the size and the weight.

The invention provides an ultra-wide-band wide-scanning-angle planar tight coupling array antenna. The antenna comprises a plurality of antenna units which are periodically arranged; the antenna unit comprises a coating layer, a radiation layer, a wave absorbing layer and a metal floor which are sequentially arranged from top to bottom and are not in contact; the radiation layer comprises a radiation layer dielectric plate, and a radiation patch and a coupling patch which are printed on the upper surface and the lower surface of the radiation layer dielectric plate; the radiation patch adopts an interdigital dual-polarization dipole structure; the coupling patch consists of a circular metal patch and four quasi-isosceles trapezoid metal patches which are spliced on the circumference of the circular metal patch and are uniformly distributed; the wave-absorbing layer comprises a wave-absorbing layer dielectric plate and an annular thin-film resistor printed on the upper surface of the wave-absorbing layer dielectric plate. The coupling patch can increase the coupling capacitance between the dipoles so as to offset inductive reactance introduced by the floor and suppress resonance points in a frequency band, and the thin-film resistor in the wave absorbing layer can convert energy of incident electromagnetic waves into heat energy, so that the energy is dissipated and attenuated, the resonance points in the frequency band are suppressed, and the working bandwidth is widened.

Techniques pertaining to wide bandwidth transmission with dynamic subchannel / subband operations in wireless communications are described. An apparatus, as a station (STA), receives an initial control frame (ICF) from an access point (AP), wherein the ICF allocates dynamic subchannel / subband operation (DSO) subband resources to DSO STAs for transmitting ICF response frames. In response to receiving the ICF, the apparatus transmits an ICF response frame to the AP, wherein the ICF response frame is transmitted according to a DSO subband resource allocated to the STA.

A method and apparatus for indicating an operating mode for an extended bandwidth in a wireless LAN system are disclosed. A method performed by a station (STA) in a wireless LAN system according to an embodiment of the present disclosure may include generating a frame including information regarding an indication of an operating channel width, and transmitting a PPDU including the frame. Here, the information regarding the indication of the operating channel width may be included in an operating mode (OM) control subfield within an aggregated-control (A-control) field of the frame, and the OM control subfield may include a specific subfield capable of indicating a wide bandwidth greater than 320 MHz.

The invention relates to the field of radar detection and signal processing, and particularly discloses a radar data technology system for monitoring a tiny target, and the system comprises a signal receiving and transmitting module which is used for generating and transmitting a linear frequency modulation signal based on a linear frequency modulation technology, and receiving an original echo signal reflected by the target; the pulse compression processing module is used for performing complex convolution operation on the original echo signal based on a matched filter to generate a compressed pulse signal; the multi-pulse coherent accumulation module is used for performing frequency domain energy accumulation on a plurality of compressed pulse signals of the same distance unit based on a discrete Fourier transform technology; and the Kalman filtering tracking module is used for processing the signals after multi-pulse coherent accumulation through a Kalman filtering algorithm, predicting and updating a target state in real time, and generating final trace point data. According to the invention, through key technologies of large-time wide-bandwidth pulse compression, multi-pulse coherent accumulation and the like, the detection capability of the radar on a tiny target is remarkably improved.

The invention discloses a C wave band reflection type phase shifter based on a cross-direction coupling line coupler, and belongs to the field of wireless communication and digital signal processing, the reflection type phase shifter is designed based on the cross-direction coupling line coupler, and compared with an existing branch line coupler and an existing Lange coupler, the C wave band reflection type phase shifter has the advantages of being small in size, low in insertion loss, wide in broadband and the like. A digital phase shifter used by a traditional phased-array antenna can be replaced, and the pain point problems of high cost, high power consumption and the like of the traditional phased-array antenna are solved; besides, the reflective phase shifter provided by the invention can be integrated on a PCB, has the advantages of being easy to process, low in cost, small in size and the like, is easy to integrate with a planar printing phased array antenna, and realizes miniaturization and low cost of the phased array antenna.

The invention discloses a multichannel photon sampling analog-to-digital conversion system and method based on a neural network. Relates to the technical field of analog-to-digital conversion. According to a traditional analog-to-digital conversion method, collected signals are transmitted mainly according to optical fibers, an analog-to-digital converter is used for analog-to-digital conversion in a high-sampling-rate and wide-bandwidth demand scene, and the analog-to-digital converter has hardware limitation of inherent photoelectric devices; the invention aims to provide a multi-channel photon sampling analog-to-digital conversion system and method based on a neural network specially for a high-requirement information processing scene, improvement is carried out on the basis of an existing photon sampling analog-to-digital conversion technology, and the multi-channel photon sampling analog-to-digital conversion system and method based on the neural network feature extraction and data reconstruction capability are obtained. And the influence of the defects of the photoelectric device is considered in the analog-to-digital conversion process, and local and global features are comprehensively considered in the data recovery process, so that analog-to-digital conversion data distortion caused by factors such as the photoelectric device is reduced, and the analog-to-digital conversion method suitable for scenes with high precision and high speed requirements is provided.

The utility model relates to a broadband wide-beam horn antenna, which comprises an antenna main body, a feed port, a feed probe, a polarizer, a waveguide and a beam widening structure, the antenna body is in a cuboid shape with an opening in the upper middle end inside, through holes are formed in the left side face and the right side face of the antenna body, feed ports are connected to the through holes, feed probes are arranged in the feed ports, a polarizer is vertically connected to the bottom face inside the antenna body, and the polarizer is located between the two feed probes. The open end of the antenna main body is connected with a waveguide, and the inner diameter of the waveguide is gradually increased along the direction close to the antenna main body to form a horn shape with a big-end-down opening; the side surface of the waveguide is provided with a wave beam widening structure which extends outwards. The antenna with the structure has the advantages that the antenna with the structure can achieve the wide-beam antenna gain of 1.5 dB within + / -60 degrees and the wide-beam antenna gain of-0.5 dB within + / -70 degrees; and the working bandwidth can reach 10%. And the diameter is only 1.27 times of the wavelength of the lowest working frequency.

The invention discloses a millimeter wave end-fire horizontal polarization broadband wide-angle scanning phased antenna array and equipment. The array comprises a lower-layer metal surface, a middle metal surface, an upper-layer metal surface, metal through holes, metal blind holes and a feed port, a radiator of the antenna array is composed of rectangular annular patches which are arranged at the front ends of an upper-layer metal surface and a lower-layer metal surface and are provided with concave U-shaped structures, and opening gaps which are etched at the central positions of the front ends of the upper-layer metal surface and the lower-layer metal surface of the substrate integrated waveguide; a plurality of antenna units in the antenna array feed independently through a plurality of feed ports and regulate and control an excitation phase; the metal blind hole is connected with the substrate integrated coaxial line; the substrate integrated coaxial line is composed of a substrate integrated waveguide and a transmission line located on a middle metal face. The substrate integrated waveguide is composed of two layers of dielectric substrates, a bonding layer, an upper-layer metal surface, a lower-layer metal surface and metal through holes. According to the invention, the broadband and wide-angle phase control scanning performance of the array beam in the plane where the array is located is realized.

Systems and methods for implementing operation-specific impedance matching for enhancing sensitivity of an ultrasound system are described. To enhance sensitivity while using a transducer element for transmission and reception, a transducer module's architecture provides operation-specific impedance matching. Operation-specific impedance matching means that different impedances are provided for mitigating mismatch loss during transmission and reception. The impedance provided for reception can be associated with separate signal path with a smaller amount of attenuation compared to the impedance provided for transmission. In this way, the architecture enhances sensitivity of the ultrasound system by reducing an amount of attenuation experienced during reception compared to other ultrasound systems that utilize a same impedance for impedance matching during transmission and reception. With enhanced sensitivity, the ultrasound system can utilize higher frequencies and / or broader bandwidths to provide high-resolution images at farther imaging depths while meeting power-intensity guidelines.

Systems and methods for implementing operation-specific impedance matching for enhancing sensitivity of an ultrasound system are described. To enhance sensitivity while using a transducer element for transmission and reception, a transducer module's architecture provides operation-specific impedance matching. Operation-specific impedance matching means that different impedances are provided for mitigating mismatch loss during transmission and reception. The impedance provided for reception can be associated with separate signal path with a smaller amount of attenuation compared to the impedance provided for transmission. In this way, the architecture enhances sensitivity of the ultrasound system by reducing an amount of attenuation experienced during reception compared to other ultrasound systems that utilize a same impedance for impedance matching during transmission and reception. With enhanced sensitivity, the ultrasound system can utilize higher frequencies and / or broader bandwidths to provide high-resolution images at farther imaging depths while meeting power-intensity guidelines.

The invention discloses a non-equilibrium Michelson interferometer electric field sensor capable of automatically calibrating temperature influence, which has the characteristics of wide bandwidth, high measurement precision and small interference of distribution of an electric field to be measured, and can also automatically calibrate temperature influence and prevent a working point of the non-equilibrium Michelson interferometer electric field sensor from deviating. The electric field sensor comprises a lithium niobate substrate, the lithium niobate substrate is provided with a non-equilibrium Michelson interferometer, the non-equilibrium Michelson interferometer comprises an input and output waveguide, the input and output waveguide is connected with a first waveguide arm and a second waveguide arm which are different in length, two sides of the first waveguide arm are provided with electrodes, and the second waveguide arm is provided with electrodes. An antenna is arranged on the electrode, a first metal reflecting mirror is arranged at the tail end of the first waveguide arm, a second metal reflecting mirror is arranged at the tail end of the second waveguide arm, the first metal reflecting mirror and the second metal reflecting mirror are both arranged on the lithium niobate substrate, and the thermal expansion coefficients of the first metal reflecting mirror and the second metal reflecting mirror are different.

The invention discloses an elastic wave filter based on an annular cylindrical shell thin plate structure and an implementation method thereof. The elastic wave filter comprises a homogeneous elastic thin plate and a resonance structure of a hollow annular cylindrical shell. By introducing an annular cylindrical shell resonance structure, efficient filtering and frequency selective control of elastic waves are realized. The filter has the advantages of high frequency selectivity, wide bandwidth control, construction flexibility, high reliability and the like, and is suitable for the fields of signal processing, sensing and the like.

Methods and devices to split electromagnetic waves across broad bandwidths in correspondence with predefined polarization state vectors are disclosed. The described methods can be used cameras or image sensors measuring directly the polarization states of an incident electromagnetic waves. The devices include three-dimensional (3D) scattering structures made of dielectric pillars and using existing CMOS processes and direct write lithography techniques. Performance metrics based on the intensity and contrast of the split electromagnetic waves are also disclosed.

The invention provides a broadband circularly-polarized metasurface antenna which comprises a first dielectric plate, a second dielectric plate, a metasurface radiator, a sequential feed network, a metal reflecting plate, a coaxial cable, a feed probe and a metal short-circuit needle. The first dielectric plate is arranged above the second dielectric plate in parallel; the metal reflecting plate is printed on the lower surface of the second dielectric plate; the metasurface radiator comprises a square patch printed in the middle of the lower surface of the first dielectric plate, and an inner ring metasurface array, an outer ring metasurface array and a quarter-wavelength branch printed on the upper surface of the first dielectric plate. The broadband circularly polarized metasurface antenna provided by the invention has the working bandwidth of 37.74%, the gain of 6.36-9.28 dBi and good directional radiation performance, and has the advantages of wide broadband, high gain and small size.

Techniques pertaining to wide bandwidth resource unit (RU) tone plan designs for next-generation wireless local area networks (WLANs) are described. An apparatus communicates wirelessly with one other apparatus by either or both: (i) transmitting first data or first information to the other apparatus; and (ii) receiving second data or second information from the other apparatus. In communicating wirelessly, the apparatus communicates in a 240 MHz, 480 MHz, 560 MHz or 640 MHz bandwidth with a subcarrier spacing (SCS) of 78.125 kHz or a multiple of 78.125 kHz.

Various schemes pertaining to long training field (LTF) and short training field (STF) transmission for wide bandwidth 240 MHz with more direct-current (DC) tones in wireless communications are described. A processor of an apparatus generates either or both of an LTF and a STF of a physical-layer protocol data unit (PPDU) with a center 996-tone resource unit (RU) having more than a predetermined number of DC tones. The processor then performs a wireless communication in a wide bandwidth (e.g., 240 MHz) with the PPDU.

According to the ultrasonic pulse generator, the echo protection circuit, the imaging system and the control method provided by the invention, the designed high-frequency pulse generator has the capability of adjusting the pulse width and the pulse edge of an excitation pulse, so that the energy frequency band distribution of a high-voltage excitation signal is regulated and controlled to better drive a transducer to generate a stronger-energy ultrasonic signal; and echo signals with higher peak values and wider bandwidth are obtained. The high-frequency pulse generator designed by the invention can realize extremely narrow high-voltage pulse signals and has rapid rising and falling edges, so that effective excitation of an ultrahigh-frequency transducer (greater than 100MHz) is realized. The T / R switch and the control mode designed by the invention can realize lower insertion loss and compression of near-field blind area time, and have practical value for improving the signal-to-noise ratio of high-frequency ultrasonic imaging. A new excitation and protection circuit mode is provided for a high-frequency ultrasonic imaging circuit system, and the high-frequency ultrasonic imaging circuit system has good economic value and practicability.

The invention relates to a waveform and dispersion comprehensive optimization method for a broadband wide-angle array-fed reflector antenna, and solves the optimization problem that the consistency of gain, sidelobe and frequency band is difficult to consider at the same time. The method comprises the following steps: extracting secondary radiation field data of the array-fed reflector antenna; carrying out feed source excitation phase structured modeling; constructing a multi-target fitness function; performing joint optimization on the two excitation parameters; and applying the optimal excitation parameters. According to the invention, an excitation phase is divided into a delay line length and a phase shifter true value, so that layered regulation and control of dispersion and waveform are realized; a multi-frequency-point multi-target fitness function is constructed, and the optimization efficiency and convergence are improved in combination with an improved multi-population genetic-particle swarm optimization algorithm; on the premise that the antenna structure is not changed, comprehensive optimization of the waveform and dispersion of the directional diagram is achieved only through phase optimization, the physical significance of modeling is clear, the control strategy is simple, the calculation efficiency is high, the engineering adaptability is high, and the method is suitable for application scenes such as GEO SAR with strict requirements for the performance of the directional diagram.

A dual-T network configured as a three-port combiner provides signal paths from two input ports to an output port, with near 0° insertion phase along one path, near ±90° insertion path along the other path, and impedance step-up along both paths. Disclosed combiners provide superior loss and impedance matching characteristics over wide (15%) bandwidth, and are suitable for use in Doherty amplifiers, which can provide high efficiency over about 10 dB output power levels, the power levels being adjusted dynamically or under switched control. Single-ended and differential Doherty amplifiers are disclosed. The combiners and Doherty amplifiers are suitable for mobile phones and other modern RF products, including battery powered products. The combiners can also serve as general-purpose quadrature couplers. Variations and performance graphs are presented.

The invention relates to the technical field of ultra-wideband antennas, and discloses an ultra-wideband wide-angle scanning tight coupling antenna and array, and the antenna comprises an impedance matching layer, an antenna radiation layer, an antenna supporting layer and a metal floor which are stacked from top to bottom. The impedance matching layer comprises three layers of eccentric cross-shaped dielectric plates, and the first eccentric cross-shaped dielectric plate at the top layer and the second eccentric cross-shaped dielectric plate at the middle layer are provided with circular grooves at the intersection center position of the two groups of orthogonal dipoles; the antenna radiation layer is provided with two groups of orthogonally arranged unequal-width pentagonal dipoles; the antenna supporting layer is provided with two groups of feed short circuit columns and two groups of metal rib belts; and the metal floor is provided with a two-section stepped feed through hole. According to the invention, the scanning range is expanded under the condition of ensuring good matching.

The invention specifically provides a low-cross-polarization ultra-wideband wide-angle scanning low-profile tight coupling phased-array antenna based on metal grid loading, and belongs to the technical field of microwave antennas. The three-order Chebyshev impedance transformer comprises a C-shaped ring metasurface loading wide-angle matching layer, a folded dipole, a double-Y balun, a three-order Chebyshev impedance transformer, a coaxial feed port, a metal floor, a metal grid, a grounding metal sheet, a resistive film, a dielectric layer and a metal chip resistor. Different polarization electromagnetic waves are regulated and controlled through the metal grid, the resistive film is introduced to absorb cross polarization components, the front-to-back ratio is improved, and the cross polarization level is smaller than or equal to-30 dB; the working bandwidth is expanded to 5.6: 1 under the condition that the profile is only 0.09 lambda by combining the size design of the non-uniform unit and the gradient balun feed, and the scanning of the wide angle of + / -60 degrees of an E surface and an H surface is supported. The invention has the advantages of compact structure, high polarization purity and wide-angle stability, and is suitable for 5G / 6G communication, radar and electronic countermeasure systems.

A single-layer broadband vertically polarized endfire magnetoelectric dipole (ME-dipole) antenna and an antenna array. The main radiator of this antenna is a substrate-integrated closed loop, which consists of two horizontal metallic strips printed on the upper and lower surfaces of substrate and a pair of vertical metallic vias. Excited by a double-sided parallel-strip line at the center of the loop, the metallic vias function as electric dipoles while the entire loop aperture works as magnetic dipole. To facilitate integration, this magnetoelectric dipole loop antenna is fed by an open-ended substrate integrated waveguide (SIW), which also works as a backed cavity to enhance the front-to-back ratio. Moreover, rectangular slots are etched at the edges of the SIW aperture to further improve the front-to-back ratio and also the cross-polarization performance. Thus, a vertically polarized endfire ME-dipole loop antenna with a low-profile structure, broad bandwidth, and stable radiation performance is achieved.