83 results about "Antenna spacing" patented technology

A method includes broadcasting, at a transmitter, messages comprising antenna configuration, antenna spacing and a number of antenna of the transmitter and reference signals; generating, at a receiver, a codebook comprising a plurality of antenna beams based on the broadcasted messages; receiving, at the receiver, the broadcasted reference signals; selecting, at the receiver, an antenna beam among the plurality of antenna beams within the codebook in dependence upon a predetermined performance criteria of a data communication system and in dependence upon the broadcasted reference signals; feedbacking to the transmitter, at the receiver, information comprising the antenna beam selected by the receiver; optimizing, at the transmitter, a beamforming process by utilizing the feedback information from the receiver; transmitting, at the transmitter, data signals by utilizing the optimized beamforming process; and receiving and processing, at the receiver, the data signals in dependence upon the selected antenna beams within the codebook.

A wireless communication system supporting improved performance in a sparse multi-path environment is provided that uses spatially reconfigurable arrays. The system includes a first device and a second device. The first device includes a plurality of antennas and a processor operably coupled to the plurality of antennas. The plurality of antennas are adapted to transmit a first signal toward a the second device and to receive a second signal from the second device. The processor is configured to determine an antenna spacing between the plurality of antennas based on an estimated number of spatial degrees of freedom and an estimated operating signal-to-noise ratio. The second device includes a receiver adapted to receive the first signal from the first device, a transmitter adapted to transmit the second signal toward the first device, and a processor. The processor estimates the number of spatial degrees of freedom and the operating signal-to-noise ratio from the received first signal.

The invention discloses an array antenna error self-correction method suitable for the field of millimeter wave vehicle-mounted radar. The method comprises the following steps: firstly, an array antenna error model is established; the model is divided into a feeder length error class and an antenna spacing error class; secondly, two targets with known position information are set; phase information on a corresponding specific distance-Doppler unit is used; a relative ideal position deviation estimation distance of the array antenna and a fixed phase error estimation angle of the array antennaare calculated to complete self-correction of the antenna array; and finally, a phase compensation scheme and an airspace steering vector are corrected through the relative ideal position deviation ofthe antenna and the fixed phase error estimation of the array antenna to complete error correction of the array antenna. The accuracy of subsequent parameter estimation is greatly improved.

A compensated resistivity logging while drilling tool having axially asymmetrically spaced transmitters is configured to provide compensated resistivity measurements. In one exemplary embodiment, the tool includes first and second compensating transmitters, preferably deployed axially symmetrically between first and second spaced receivers. The tool further includes a plurality of transmitters deployed axially asymmetrically with respect to the receivers, e.g., on one axial side of the receivers. The compensating transmitters are configured to acquire a borehole compensation that may be subtracted from conventional phase and attenuation measurements.

The invention discloses a method for measuring the grain moisture content based on a microwave frequency sweep technology. The measuring method adopts a grain moisture content measuring device based on a frequency sweep microwave penetration method. The method mainly comprises the steps of setting an initial microwave frequency sweep signal MSS according to the characteristics of different kinds of grains, removing poor frequency points corresponding to a great reflection coefficient [Gamma] and standing-wave ratio [Rho] in the MSS by taking the automatic alignment of microwave antennas as a basis to obtain an optimized frequency sweep signal MSS'; determining and adjusting to the optimum measurement distance and inter-antenna distance according to three conditions such as an antenna far field condition, the representativeness of the moisture content measurement result and microwave space transmission loss reduction; mutually interacting the radiation optimized frequency sweep signal MSS' and the grain to be measured, inputting the microwave attenuation A and the microwave phase shift [Phi] into a grain moisture content prediction model to calculate the grain moisture content measurement result. The method not only uses the microwave frequency sweep technology, but also optimizes the used frequency sweep signal, is comprehensive in consideration when the microwave attenuation is calculated, and improves the accuracy of the grain moisture content measurement.

Provided is a wireless positioning calibration system, including a plurality of transmission base stations, at least one sniffer base station and a positioning server. The at least one sniffer base station receives a plurality of channel state information (CSI) transmitted by the plurality of transmission base stations. The positioning server receives the plurality of CSI transmitted by the at least one sniffer base station. The positioning server calculates a phase error and an antenna spacing error generated by the at least one sniffer base station by means of the plurality of CSI, and compensates the phase error and the antenna spacing error. A wireless positioning calibration method is also provided.

In a MIMO communication system that includes a transmitter and a receiver and forms line-of-sight orthogonal channels between the transmitter-side transmitting antenna and the receiver-side receiving antenna, the MIMO communication system is provided between the transmitting antenna and the receiving antenna with an optimum antenna-to-antenna spacing shortening unit to shorten an optimum antenna-to-antenna spacing by changing the phase rotation of a carrier wave used for directly opposed waves between opposed antennas, and the phase rotation of a carrier wave used for intersecting waves between oblique antennas in such a manner that the amount by which one of the phase rotations changes is different from that by which the other phase rotation changes.

There is provided a communication device including: a receiving unit that receives radio signals transmitted from another communication device using a plurality of transmitting antennas by a plurality of receiving antennas; an estimation unit that estimates a range of a position where said another communication device possibly exists based on a phase of each radio signal received by the receiving unit and antenna spacing between the transmitting antennas; and a position determination unit that determines an existing position of said another communication device within the range estimated by the estimation unit.

The elements of a phased array antenna are driven by different frequencies, rather than the same frequency, to realize a scanning beam. The scan rate of the beam may be set arbitrarily high according to the frequencies used to drive the phased array, without expensive phase modulators. In particular, each successive element of the phased array antenna is driven with a frequency that is offset from the frequency used to drive the previous element in direct proportion to the spacing between antenna elements. Thus, for a straight line implementation of a phased array antenna with an antenna spacing offset of λ/2, the frequency offset between adjacent antenna elements is constant. For implementations of phased array antennas with another linear or a non-linear spatial relationship between antenna elements, the frequency offset between adjacent antenna elements is determined based on a linear or non-linear spatial relationship of the antenna.

The invention discloses a clock homology Beidou/GPS aviation augmentation system based on analog light transmission, and relates to signal light transmission between antennas and receiving processing plates of four reference receivers of the aviation augmentation system, centralized installation of the receiving processing plates and high precision clock centralized supply. The clock homology Beidou/GPS aviation augmentation system based on analog light transmission is composed of the antennas, low noise amplifiers, light transmitting modules, optical fibers, light receiving modules, the receiving processing plates, a multi-serial port card, an industrial personal computer, a power source and the like. According to the clock homology Beidou/GPS aviation augmentation system based on analog light transmission, the analog light transmission technology is used, signals of Beidou/GPS active antennas are transmitted to the receiving processing plates through the optical fibers, the transmission distance problem is solved in the centralized installation mode, the antenna distance of the four receivers can exceed 100 meters, the receiving processing plates can be mounted in a centralized mode, and high precision clock centralized supply can be achieved. The system has the advantages of being high in anti-electromagnetic interference capacity, convenient to mount and maintain and the like. Due to the high precision clock centralized supply, the performance and the stability of the system are improved.

The invention discloses a method for correcting the direction-finding coning effect of a one-dimensional interferometer, based on the direction-finding principle of the one-dimensional interferometer, a signal arrival angle theta is shown in the specification, phi is the phase difference of two paths of signals, lambda is the signal wavelength, l is the antenna spacing, and when an incident signal and an antenna visual axis are not in the same plane, the coning effect exists. The correction method comprises the following steps: based on an obtained signal pitch angle beta and a measured signal arrival angle theta, completing correction calculation of an azimuth angle alpha through the following formula: alpha = sin-1 (sin theta/cos beta). According to the method, the influence of a coning effect caused by a large pitch angle can be avoided, and the azimuth direction finding precision of the one-dimensional interferometer can be improved.

The invention discloses a vehicle-mounted MIMO radar antenna layout structure which is applied to a radio frequency chip. The layout structure comprises a first transmitting antenna group which comprises a plurality of first transmitting antennas extending and arranged along a first direction, a second transmitting antenna group which comprises a plurality of second transmitting antennas which extend and are arranged along the first direction, and a first receiving antenna group which comprises a plurality of first receiving antennas which extend and are arranged along the first direction, wherein the second transmitting antenna group is located between the first transmitting antenna group and the first receiving antenna group in a second direction, and the second direction is perpendicular to the first direction. According to the invention, the axisymmetric structure is utilized, the distance from the antenna at the farthest end of the radio frequency chip to the radio frequency chippin is the shortest, and the minimum feeder loss is realized; and long-distance transmitting antennas and short-distance transmitting antennas extend along different transverse lines, so that the problem of layout interference caused by the problem of antenna spacing between the antennas can be avoided.

The invention discloses a self-adaptive direction finding antenna used for measuring a signal direction of a mobile phone and a measuring method thereof. A single-dimensional self-adaptive direction finding antenna and a three-dimensional self-adaptive direction finding antenna are included. The single-dimensional self-adaptive direction finding antenna comprises three antenna units, a screw rod,a slide rail, a servo motor, two fixed seats and a slide seat. The three antenna units are fixedly arranged on the two fixed seats and the sliding seat. The two fixed seats are fixed to two ends of the sliding rail respectively and sleeve the sliding rail and the screw rod. One end of the screw rod is connected with a servo motor and is driven by the servo motor to rotate, and a position of the sliding seat is adjusted. The three-dimensional self-adaptive direction-finding antenna is composed of three groups of single-dimensional self-adaptive direction-finding antenna end portions which are vertical to each other, and an antenna unit at an intersected end of the three groups of self-adaptive direction-finding antennas is shared as a common reference antenna unit. In the invention, a distance between the direction-finding antennas can be changed according to working frequency of a signal whose direction needs to be found, and a purpose of flexibly adapting to signals with different frequencies is achieved.

A method for calculating a spacing between antenna elements of an interferometer array antenna includes setting an azimuth of an instantaneous field of view and a distance between phase differences, and obtaining the number of phase difference lines and phase difference vectors with respect to the phase differences of the signals output in a phase comparator of a direction finder, performing a modular arithmetic for the phase difference vectors to obtain phase difference matrixes, obtaining a transformation matrix for linearly transforming the phase difference matrixes and performing the linear transformation using the transformation matrix, calculating a distance between the phase differences on a new axis generated by the linear transformation, and calculating an antenna spacing as an array spacing of the array antenna, the antenna spacing meeting that the distance between the phase differences is greater than a desired distance between phase differences.

The invention provides a design method of an anti-interference scattering communication system antenna array, which is a communication system scattering field antenna array design method capable of enhancing scattering signal intensity and realizing scattering field beamforming, and the design can be used for a scattering communication system to improve communication performance such as communication radius expansion and interference resistance. The method is characterized in that a design method capable of realizing beamforming in any direction in a three-dimensional space is provided based on geometrical characteristics of the three-dimensional space and characteristics of an antenna array; MATLAB and HFSS are adopted to carry out joint design simulation; the HFSS establishes a scatter communication system antenna array model, the array element antenna spacing of the scatter communication system antenna array model is set to be a variable quantity, and MATLAB calculates the optimal array element antenna spacing by adopting a differential evolution algorithm and the HFSS in a combined manner. According to the method, the differential evolution algorithm and the HFSS are adopted onthe MATLAB for joint calculation, so that the antenna scattering direction in the scattering communication system antenna array can be centralized.