88 results about "Grating lobe" patented technology

The invention relates to the technical field of array antennas, and discloses a common-caliber layout-based ultra-wideband array antenna, which comprises a low-frequency unit and a high-frequency unit which are arranged based on a common caliber, and is characterized in that the working frequency of the low-frequency unit covers an fmin-f0 frequency band, and the working frequency of the high-frequency unit covers an f0-fmax frequency band. The low-frequency unit is a broadband dual-polarized antenna, a uniform tight coupling array distributed at equal intervals is formed by adopting a tight coupling principle, and the unit interval is calculated based on a grating lobe suppression condition at the frequency f0. The high-frequency unit is a miniaturized broadband dual-polarized antenna and adopts a sparse array form; the initial unit spacing and the unit number of the sparse array are calculated based on the grating lobe suppression condition at the highest frequency f2 of the f1-f2 frequency band with the side lobe requirement between the f0-fmax frequency bands. The ultra-wideband array antenna gives consideration to full-band array performance, can provide sufficient space for active circuit arrangement, and effectively reduces power consumption and cost.

The invention discloses a non-line-of-sight moving target three-dimensional reconstruction method based on an MIMO millimeter wave radar, and is applied to the technical field of radar target detection in a complex urban environment. Aiming at the problem of difficulty in realizing three-dimensional reconstruction of a non-line-of-sight moving target in the existing radar target detection technology, the method comprises the following steps: firstly, establishing a non-line-of-sight multipath propagation model, and exporting a multipath signal model of an MIMO millimeter wave radar; the invention further provides a multipath signal departure angle (DoD) / arrival angle (DoA) unambiguous estimation algorithm, and solves the problem that a main lobe and a grating lobe are difficult to distinguish in the DoD / DoA estimation process of an existing commercial MIMO radar. And finally, proposing a path-oriented non-line-of-sight target three-dimensional positioning algorithm, respectively positioning the non-line-of-sight target by using different paths, and fusing different path positioning results to form a three-dimensional point cloud. According to the method, three-dimensional reconstruction of a plurality of non-line-of-sight moving targets can be realized, and the correlation problem between paths does not need to be considered.

A method and system for low Earth orbit (LEO) satellite multiple access and communication using grating lobes is disclosed. The method may include: acquiring ephemeris data for a plurality of LEO satellites; predicting an orbital trajectory for each of the plurality of LEO satellites based on the ephemeris data; selecting target satellites using the predicted orbital trajectories; adjusting an antenna array to form grating lobes in the directions of the selected target satellites; and transmitting and receiving data with the target satellites using the adjusted antenna array.

A quad-polarized antenna system according to the present invention comprises a plurality of RF chains, and an antenna array in which rows of first dual-polarized antenna units and rows of second dual-polarized antenna units are alternately arranged in a horizontal direction. The first dual-polarized antenna unit and the second dual-polarized antenna unit have different dual polarization characteristics from each other. The rows of first dual-polarized antenna units are used to form at least one first beam and at least one second beam which have + / −45° polarizations, and the rows of second dual-polarized antenna units are used to form at least one third beam and at least one fourth beam which have 0° / 90° polarizations. The first beam, the second beam, the third beam, and the fourth beam are formed towards different spatial directions, and the first and third beams correspond to main lobes, and the second and fourth beams correspond to grating lobes.

The invention discloses an antenna unit capable of being used for a low RCS array, and belongs to the technical field of antennas. The antenna comprises a radiation structure layer and a feed network layer. The radiation structure layer comprises rectangular metal patches and special-shaped metal patches which are arranged in an array. The rectangular metal patches form a 2 * 4 array in the same plane; the number of the special-shaped metal patches is two, and the two special-shaped metal patches are located below the 2 * 4 array. The feed network layer is located below the radiation structure layer, and a T-shaped branch knot is arranged between an upper metal plate and a lower metal plate of the feed network layer; a radio frequency socket is arranged at the bottom of the lower metal floor, and an outer conductor of the radio frequency socket is connected with the lower metal plate; an inner conductor of the radio frequency socket penetrates through the lower metal floor and is connected with a common end of the T-shaped branch knot, and two branch ends of the T-shaped branch knot are connected with the corresponding special-shaped metal sheets through the corresponding feed probes. According to the invention, a radiation function and a scattering control function are integrated, so that the radiation performance of the antenna is ensured, and the RCS of the unit and the scattering grating lobes during array splicing use are obviously reduced.

The application discloses a STCA-MIMO radar anti-interference method based on nonlinear time delay, which comprises the following steps: calculating target echo signals based on nonlinear time delay of transmitting array elements; carrying out digital mixing and matching filtering on the target echo signals to obtain preprocessed signals; determining a first transmitting steering vector and a first receiving steering vector according to the preprocessed signals; calculating a covariance matrix of STCA-MIMO radar system receiving data; calculating an adaptive weight vector by using a robust direct data domain beam forming technology based on the covariance matrix and an actual receiving-transmitting joint steering vector of a target; calculating a first receiving-transmitting joint steering vector of the STCA-MIMO radar system; and carrying out beam forming by using the first receiving-transmitting joint steering vector and the adaptive weight vector. The application can effectively suppress interference signals in the main lobe of the STCA-MIMO radar, and solves the problem of the decline of interference suppression performance in the prior art when the interference is located near the distance grating lobe of the main lobe of the real target.

The application discloses a kind of based on rectangular waveguide lens terahertz two-dimensional multi-beam antenna, including two-dimensional feed array, rectangular metal cavity and rectangular waveguide lens;Two-dimensional feed array includes first metal substrate, first metal substrate is provided with several rectangular waveguide feed units, each rectangular waveguide feed unit is connected with feed port;Rectangular waveguide lens includes second metal substrate, second metal substrate is provided with several rectangular waveguide phase shift units, and the rectangular waveguide phase shift units of adjacent row are mutually staggered distribution.The application is realized two-dimensional multi-beam scanning by the way of two-dimensional feed array bias feed, with the advantages of two-dimensional scanning angle and gain can be arbitrarily designed, large bandwidth advantage.The application adopts rectangular waveguide array to form metal lens, with the advantages of low high-frequency loss, small size;At the same time, through waveguide array staggered and period compression, mirror image grating lobe is eliminated, with the advantages of low grating lobe, large scanning angle.

The application provides a metasurface array, which is composed of several metasurface subarrays of different shapes; the metasurface subarrays cannot coincide with the original metasurface subarrays after being rotated by 90°, or 180°, or 270°, or being mirror flipped, the application adopts irregular subarray division for a super large scale reflector array, compared with a traditional structure without subarrays, the number of bias lines is greatly reduced, that is, the number of control interfaces of the smart reflector is reduced, under the condition that the performance indicators such as scattering pattern gain and sidelobe are slightly reduced; compared with regular subarray division, the grating lobe level can be obviously suppressed due to breaking the periodicity of the phase center of the subarray, and the application can effectively reduce the system cost, power consumption and engineering implementation difficulty.

This invention discloses a method for suppressing high sidelobes / grating lobes in a wide-area ultra-sparse MIMO radar system, comprising the following steps: (1) Based on a MIMO radar with sparse node distribution, select one set of array elements, each array element transmits orthogonal waveforms to obtain a joint transmit / receive beam pattern; (2) By changing the carrier frequency, obtain joint beam patterns respectively, multiply the obtained beam patterns to obtain an optimized joint beam pattern; (3) Select another set of array elements, repeat steps (1) and (2) to obtain joint beam pattern results under different array configurations; (4) Multiply the joint beam patterns under all array configurations to obtain the final optimized joint beam pattern. By multiplying the carrier agility results of the joint transmit / receive beam patterns obtained from different carrier frequencies of different MIMO radar transmit / receive array configurations, the joint transmit / receive beam pattern optimization is achieved, resulting in a joint transmit / receive beam pattern with lower sidelobes.

The invention discloses a loudspeaker array beam forming method, electronic equipment and a storage medium, and relates to the technical field of beam forming, and the method comprises the steps: obtaining a distance value between each loudspeaker unit in a loudspeaker array and a corresponding impedance boundary, and an impedance value of the impedance boundary; matching a target beam forming filter in a plurality of preset beam forming filters according to the distance value and the impedance value; and filtering the input signal of the corresponding loudspeaker unit based on each target beam forming filter to form an output beam. In practical application, the applicable beam forming filter can be quickly matched only by acquiring the specific impedance boundary parameters of the current environment, the method can adapt to the boundary environment with limited acoustic impedance characteristics, the influence of the impedance boundary on sound wave propagation is accurately reflected, the beam pointing precision and the acoustic contrast are remarkably improved, and the method is suitable for popularization and application. And the grating lobes of the dark area are reduced, so that the optimization of the beam performance is realized on the premise of not needing on-site acoustic measurement, and the universality and the accuracy are both considered.

The application discloses a large-interval wide-angle scanning phased array antenna design method and system, and belongs to the technical field of array antenna design. The application adopts parameterized setting of block number to improve the degree of freedom of optimization. Since each block condition may exist a better solution, the block type of the region is substituted into the optimization variable, so that the final optimization result can be prevented from falling into a local optimum, and the optimal solution can be more likely obtained. The dense arrangement form of the divided region can effectively control the interval of adjacent array elements, avoid the overlapping of adjacent array elements, and improve the optimization efficiency. In addition, the regular layout is beneficial to the back-end network design, and reduces the complexity of the feed network. The dense arrangement and array element selection combination can effectively enlarge the interval, and can make the interval not appear grating lobe, thereby reducing the number of channels and reducing the cost. The array element position micro-adjustment provides more possibilities for large-angle scanning optimization, improves the optimization efficiency, and breaks the periodic arrangement form.

The invention discloses a satellite-borne phased array low-grating lobe antenna array plane, which is characterized in that a plurality of units are arranged on the array plane, an inner ring and an outer ring are sequentially arranged from the center to the outer side of the array plane, the units on the inner ring are arranged to be a plurality of concentrated structures, the units on the outer ring form a plurality of non-uniform discrete structures, and the units are gradually sparsely arranged from the inner ring to the outer ring. And the periodicity of the array plane is destroyed. The antenna array plane ensures that the antenna core gain is not lost through the inner ring concentration structure, and provides basic performance support for communication / detection; the combination of the outer ring non-uniform discrete structure and the sparse arrangement fundamentally destroys the periodicity of the array plane, scatters grating lobe energy into weak dispersion signals, and achieves powerful grating lobe suppression. Meanwhile, the number of antenna units, matched T / R assemblies and radio frequency channels is greatly reduced through sparse arrangement, the array surface weight and the system cost are remarkably reduced, sufficient space is reserved for heat dissipation, and finally the optimal balance among wide-angle scanning, anti-interference performance and satellite-borne engineering practicability is achieved.

This invention discloses a phase-open-loop hierarchical phase-shifting beamforming method, comprising the following steps: Step 1: uniformly dividing the array beam scanning space into N Scan Step 1: Inject random phase weights into the first phase shifter at the first stage; Step 2: Scan angle θ i Step 4: Apply a scanning phase to the first-stage phase shifter and calculate the phase shift of the first-stage phase shifter; Step 5: Calculate the phase shift of the second to Nth-stage phase shifters using a penetration beamforming algorithm; Step 6: Correct the median shift of the phase shift of each stage phase shifter; Step 7: Repeat steps 3 to 5 until all scanning angles are traversed, and record the maximum grid lobe sidelobe level within all scanning angles as L. l Step 7: Repeat steps 2 through 6 until the maximum number of iterations is reached; Step 8: L l The minimum is L best The corresponding iteration uses the optimal beam phase weight for the full-scan spatial domain. This invention can effectively reduce the grating lobe sidelobe level, is simple to implement, and is suitable for low-cost antenna arrays.

The utility model discloses a low-grating lobe open waveguide antenna in the field of antennas, which comprises a waveguide shell integrally in a horn mouth shape, a small-caliber end of the waveguide shell is an input port, a large-caliber end of the waveguide shell is an output port, and the inside of the waveguide shell is divided into at least three stages of matching steps; the distribution part is fixedly arranged at the output port of the waveguide shell; the suppression part is arranged on the matching step close to the output port of the waveguide shell and connected with the distribution part, the suppression part is of a plate-shaped structure, and the extension direction of the suppression part is the E-plane direction of the waveguide shell; the beneficial effects of the utility model are that the output port of the waveguide housing is provided with the cross-shaped grid bar and the suppression metal block, so that the output port can be divided into four independent open waveguide radiation units for radiation, and the power division network level and grating lobe level of an array antenna formed by the units are reduced.

The application discloses a metal antenna radiation structure and an antenna array, and relates to the technical field of communication. In the main body radiation structure, more than two levels of layered structures are arranged along the height direction, the lateral size of each layer is gradually increased from bottom to top, a stepped expansion amplification structure is formed, gradual transition and impedance smooth change of electromagnetic energy in the vertical direction are realized, effective radiation is realized without loading high-loss dielectric materials, and the problem of efficiency reduction caused by dielectric loss is reduced. The multi-stage metal gradual expansion structure can compress the overall height under the premise of guaranteeing the radiation performance and bandwidth characteristics, optimize the current distribution, enhance the directivity control ability, provide a structural basis for compact arrangement and suppression of grating lobes of the array, and is suitable for low-profile, miniaturization and high-efficiency application scenarios. The technical problems that the radiation efficiency is insufficient and the structural thickness is difficult to be considered under the condition of low profile are solved, and the technical effects that high-efficiency radiation and structural compactness are realized while reducing loss are achieved.

The application discloses a movable array element anti-interference position beam joint method facing unknown direction, introduces movable array elements, and makes array geometry structure be treated as adjustable optimization variable in deployment stage. By changing equivalent array element spacing and pattern structure of the array, the separable degree of expected signal and interference signal incident direction on the spatial response is improved, and the destructive influence of strong interference on the array output when falling in the high side lobe / grating lobe direction of the array is reduced. In each candidate position, an adaptive beam forming process with a pilot sequence as a reference is adopted to directly generate a beam forming weight vector corresponding to the position, so that the mean square error of the receiving output in the pilot interval is minimized. The "movable array element position-performance index" is modeled as a target function to be optimized, and a global adaptive search method based on a probability model is adopted to select the next evaluation position in an iterative manner, instead of exhausting evaluation on all candidate positions.

The invention particularly relates to a sparse array DOA (direction of arrival) estimation method based on an optimized array manifold dictionary, and the method comprises the steps: firstly carrying out the layout optimization of an initial uniform area array through combining a genetic algorithm, constructing an eight-element sparse array structure, and maintaining a directional diagram which is close to a full array while greatly reducing the number of array elements; performing energy screening on multichannel observation signals acquired by the sparse array, and extracting a dominant frequency band to improve an effective signal-to-noise ratio; and an optimized array manifold dictionary is constructed based on a phase compensation mechanism and an amplitude weighting mechanism, and the internal correlation of the dictionary is reduced by minimizing off-diagonal elements of a dictionary Gramer matrix. And on the basis, sparse reconstruction is carried out on the optimized dictionary by using an orthogonal matching pursuit algorithm, so that a direction-of-arrival estimation result of the sound source signal is obtained. According to the scheme, inherent direction finding fuzziness and grating lobes of the sparse array are effectively suppressed, the direction estimation precision is improved, and high reliability and high robustness are still kept under the condition that the number of array elements is remarkably reduced.

An array antenna for reducing grating lobes and cross polarization leakage is disclosed. The array antenna includes a plurality of first element units arranged in a first column, each first element unit including two elements having a specific distance that differs from a distance (dy) of one element by a predetermined value; and a plurality of second element units arranged in a second column adjacent to the first column, each second element unit including two elements having the specific distance, the second element units being arranged to be spaced apart from the first element units by a distance (dy) of one element, the first element units and the second element units being alternately and repeatedly arranged in the row direction, each of the first element unit and the second element unit includes one or more dummy patches configured to have no electrical signal connection.

The application relates to the technical field of wideband digital beam forming, and discloses a large-scale wideband digital subarray beam decoupling and grating lobe suppression method and system.The method comprises the following steps: a subarray array synthesis unit generates array synthesis beam data in a subarray according to received digital signals and array weights in the subarray; an array beam synthesis unit generates array synthesis beam data between subarrays according to received array synthesis beam data in the subarray and array weights between the subarrays; a beam verification unit respectively calculates a main lobe amplitude and a grating lobe amplitude according to the array synthesis beam data between the subarrays, calculates a main-to-grating ratio according to the main lobe amplitude and the grating lobe amplitude, evaluates whether a current subarray division result meets actual engineering use requirements according to the main-to-grating ratio, and stops until all effective subarray division results are traversed; and the subarray division result corresponding to the maximum main-to-grating ratio is taken as a final subarray division result.The application greatly reduces resource consumption and hardware cost, and improves grating lobe suppression effect.

The invention relates to the technical field of antennas, in particular to a K-Ka double-frequency common-caliber satellite communication active phased-array antenna which comprises an antenna array plane and TR assembly integrated plate, a metal heat conduction structure cavity, a wave control assembly and power supply assembly integrated plate, a metal heat conduction structure cover plate and the like. The antenna array plane and TR assembly integrated plate serves as a core carrier, spatial multiplexing of a transmitting frequency band (Ka) and a receiving frequency band (K) in the same physical caliber is achieved through a nested double-frequency layout and a multi-layer shielding structure, Ka-frequency-band transmitting arrays are concentrated in the center in a # shape, K-frequency-band receiving arrays surround the periphery, high-frequency-band small spacing is adapted, grating lobes are avoided, and the antenna array plane and the TR assembly integrated plate are integrated. Meanwhile, the three-layer PCB structure (the receiving link radio frequency wiring layer, the grounding inner layer and the transmitting link radio frequency wiring layer) is shielded through the grounding inner layer, and the copper surface isolation frame is combined, so that the isolation degree of a transmitting channel and a receiving channel can be improved, and the problem of high-frequency interference in an application scene of low-orbit satellite terminal equipment is effectively solved.

The invention discloses a distributed coherent aperture radar angle ambiguity resolution method based on maximum likelihood estimation in the technical field of radar signal processing. Aiming at the problem of angle ambiguity of the distributed coherent aperture radar caused by transmitting beam grating lobes, the method comprises the following steps: firstly, transmitting a group of carrier frequency linear stepping pulse sequences; then carrying out beam forming on received echoes, and carrying out coherent accumulation on beam output of a plurality of pulses by utilizing the characteristic that main lobe response does not deviate along with the frequency and grating lobe response deviates along with the frequency, so as to suppress grating lobes and enhance the main lobe on the aspect of energy; and finally, modeling is carried out on the accumulated signals, and unambiguous angle estimation is realized by solving a conditional maximum likelihood estimator of a target direction. The method can effectively solve the problem of angle measurement ambiguity caused by transmitting grating lobes under the condition that the beam coverage range is not lost, and particularly has the advantages of high precision and high robustness in a low signal-to-noise ratio environment.

The application provides an array antenna and a communication device. The antenna unit of the array antenna comprises a first antenna and a second antenna. The working mode of the first antenna comprises a high-order mode of a first polarization mode and a high-order mode of a second polarization mode, and the working mode of the second antenna comprises a main mode of the first polarization mode and a main mode of the second polarization mode. In this way, by controlling the first antenna and the second antenna to jointly receive signals or transmit signals, the gain of the first antenna in the high-order mode and the gain of the second antenna in the main mode can be combined with each other, which is beneficial to reducing the gain of the grating lobe generated by the array corresponding to the plurality of second antennas when the array works in the main mode, thereby increasing the spacing between the antennas in the array antenna while ensuring the communication performance of the array antenna, and further reducing the layout difficulty of components in the array antenna supporting polarization reconstruction and improving the performance of the array antenna in the polarization reconstruction process.

The invention discloses an on-chip pure-solid-state optical scanning system for large-angle continuous scanning without a blind area. A light source input area, a 1 * N switch array, N spot-size conversion units, N active refraction units and N inclined grating emission units are sequentially integrated on the same photon chip substrate. Different light paths are gated through the switch array, and the grating emission units with different fixed inclination angles are selected to realize discrete hopping of a horizontal angle; by continuously and independently adjusting the refractive index of the active refraction unit of each channel, continuous compensation fine adjustment is carried out on the incident direction of the light beam, so that discrete angle intervals are seamlessly filled, and finally continuous and non-blind area scanning in a 180-degree view field is realized in the horizontal direction. And pitching scanning can be synchronously realized in combination with wavelength tuning. The scheme is based on pure solid-state on-chip integration, has no mechanical moving part and external lens, has the advantages of no side lobe and grating lobe, simple control, low power consumption, small size, good process compatibility and the like, and is suitable for the fields of laser radar, free space optical communication and three-dimensional sensing.

The application discloses a kind of based on the construction method of frequency band overlap unit's ultra-wideband heterogeneous array aperture optimization mathematical model, include the following steps: according to unit type and operating frequency band, heterogeneous array is divided into several subarrays, unit type and operating frequency band are consistent in each subarray;Establish the heterogeneous array directional diagram expression considering the shared aperture when different frequency bands overlap;Further combined with the performance requirements of ultra-wideband, the array radiation performance constraint condition is constructed;According to each operating frequency and scanning angle range, establish the subarray element spacing constraint condition, to avoid producing grating lobe;Establish array aperture constraint condition, for limiting array total aperture size in preset range;Comprehensive above directional diagram expression and various constraint conditions, the ultra-wideband heterogeneous array aperture optimization mathematical model is constructed.The application establishes the construction method of frequency band overlap unit's ultra-wideband heterogeneous array aperture optimization mathematical model, provides theoretical model for subsequent design of ultra-wideband heterogeneous array.

This invention proposes a direction-of-arrival (DOA) estimation method based on a sparse circular array using the golden ratio. The method defines the antenna position and three-dimensional coordinates using the golden ratio, constructing a sparse array. A DOA vector is established based on the azimuth and elevation angles, and the path difference and phase difference are calculated. These are then combined with multi-shot data to form a covariance matrix. To improve robustness under low snapshot and low signal-to-noise ratio conditions, adaptive diagonal loading is employed to adjust the noise eigenvalue distribution and enhance the distinguishability between the signal and noise subspaces. Addressing the issues of traditional MUSIC algorithms' accuracy depending on step size and poor real-time performance, a three-step search is designed: a coarse search to locate local maxima, a ternary trigonometric iteration to narrow the interval, and a fine search followed by quadratic surface fitting to eliminate grid errors. This method effectively suppresses sparse array grating lobes, balancing high accuracy and real-time performance.

The invention discloses a rocket-borne large-spacing ultra-wideband conformal phased-array antenna, and belongs to the technical field of phased-array antennas. The antenna comprises a rocket body conformal metal carrier, a metasurface layer, an antenna layer, a parasitic layer, a metal floor and a fixing structure, wherein the antenna layer is formed by periodically arranging dual-polarization orthogonal active antenna units, vertical polarization units are linearly arranged along the axial direction, and horizontal polarization units are conformally bent along the cylindrical surface side of a rocket body; the parasitic layer is composed of passive parasitic units which are correspondingly arranged, the passive parasitic units and the active antenna units are alternately arranged in an orthogonal grid mode, and reverse current is excited by arranging a short-circuit strip so that H-face harmful common-mode resonance can be restrained. The antenna provided by the invention realizes nine frequency doubling bandwidths in a horizontal line polarization direction and a vertical line polarization direction, and realizes + / -60-degree grating lobe-free wide-angle scanning of an azimuth plane when an array spacing is 0.7-0.9 lambda H by adopting a rocket body conformal mode.

The application relates to an antenna layout method and system for ground penetrating radar receiving end beam forming, and relates to the field of ground penetrating radar detection. The method solves the problem that, in a conventional ground penetrating radar, a multi-channel scheme is adopted, the number of transmitting and receiving antennas is increased to improve the lateral detection range, and due to time lag of channel data and beam forming difficulty, the potential of the array antenna cannot be fully utilized. The method comprises the following steps: determining the form of a ground penetrating radar antenna array according to the requirement of beam forming; constructing an equivalent directional diagram of the antenna array layout according to the form of the radar antenna array; suppressing the grating lobe phenomenon in the equivalent directional diagram of the antenna array layout; suppressing the coupling effect in the equivalent directional diagram of the antenna array layout; and suppressing the direct wave from the transmitting antenna to the receiving antenna according to the polarization direction of the antenna in the suppressed equivalent directional diagram, so as to complete the antenna layout. The application is applied to the field of underground nondestructive imaging.

The invention discloses a low-profile two-dimensional scanning large-spacing phased-array antenna and electronic equipment, and belongs to the technical field of communication and radar. The antenna comprises a plurality of overlapped radiation linear arrays arranged along the horizontal direction and a plurality of passive interleaving feed networks arranged along the vertical direction. The overlapped radiation linear array is formed by overlapping radiation sub-arrays composed of driving units, passive units and coupling units, and sinc function aperture distribution is achieved in the vertical dimension so as to suppress vertical scanning grating lobes. The passive interleaving feed network is formed by interleaving a plurality of feed elements, and sinc function excitation amplitude distribution is realized in a horizontal dimension to suppress horizontal scanning grating lobes. The two phase shift ports are combined to form a two-dimensional planar array, and the phase shift port spacing is greater than or equal to lambda 0. According to the invention, a full-passive planar circuit structure is adopted, a complex active device and a high-profile electromagnetic structure are not needed, low-profile, low-cost and high-reliability two-dimensional beam scanning is realized, the grating lobe suppression is greater than 10dB in a scanning range of + / -20 degrees, and the antenna is particularly suitable for being applied to a millimeter wave frequency band.

A communication method and apparatus, relating to the technical field of communications. In the method, by constructing a grating lobe, and using joint scanning of a transmitting array and a receiving array (that is, setting a transmission scanning parameter of a transmitting node and a reception scanning parameter of a receiving node in an association manner), the scanning overhead can be reduced while the sensing performance gain is ensured.

The present invention provides a method which is suitable for being used within a communication network comprising at least one main communication device (1) having at least one antenna array (1a), which is able to provide service by broadcasting directional signal beams by generating serving lobes (4) and non-serving lobes (5), and having at least two RF chain (1b) ensuring generation of the lobes, at least one user device (3) which is capable of communicating with the main communication device (1) through the serving lobes (4), at least one secondary device (2) which is capable of communicating with the main communication device (1) through the non-serving lobes (5). The method is configured to provide physical layer security with spatial aliasing in wireless networks comprising MIMO systems which ensure usage of grating lobes for various processes such as back-scattered communication, energy harvesting and identification. The method comprises generation of overlapping non-serving lobes (5) to provide service to the secondary devices (2).