140 results about "Antenna radiation patterns" patented technology

A system and a method for code division multiple access (CDMA) communication. The system includes fixed terminals communicating with a central base station. The terminals in protection sectors of each sector are configured to employ codes from different sets of codes to overcome potential mutual interference between sectors on account of antenna radiation pattern roll-off. The remaining codes, preferably the majority of the available codes, are used in any one of a plurality of basic sectors, each of which separates the protection sectors of a respective sector. For an even number of sectors in a cell, the available codes are partitioned into three groups, two for the protection sectors and one for the basic sectors. For an odd number of sectors in a cell, the available codes are partitioned into four groups, three for the protection sectors and one for the basic sectors. Protection sectors are relatively narrow but broad enough to counteract the potential mutual interference between sectors.

An antenna comprising an IMD element, and one or more parasitic and active tuning elements is disclosed. The IMD element, when used in combination with the active tuning and parasitic elements, allows antenna operation at multiple resonant frequencies. In addition, the direction of antenna radiation pattern may be arbitrarily rotated in accordance with the parasitic and active tuning elements.

A wireless apparatus capable of controlling radiation patterns and directions of antenna is provided. It comprises an antenna element, a ground plane, an antenna feed-point, and at least one slot or slit formed on the ground plane. The inclusion of such slots or slits in the wireless apparatus improves the radiation directivity of antenna, and greatly enhances the antenna gain on the horizontal plane. It also resolves the problems caused by shift of radiation patterns of antenna and the poor antenna gains for a conventional antenna apparatus. The wireless apparatus of the present invention has the advantages of simple structure and easy fabrication. The invention can be applied to various kinds of antennas, such as monopole antenna, shorted-monopole antenna, dipole antenna, loop antenna, and planar inverted-F antenna, etc.

The invention discloses a side-lobe suppression method for a three-dimensional array antenna pattern based on an improved MOPSO and a convex optimization algorithm. Firstly, three-dimensional array antenna pattern synthesis is modeled and analyzed, and a basic mathematic model of the array antenna radiation pattern synthesis is given, and multi-objective functions of low side-lobe pattern synthesis under constraint conditions of an array radiation direction and first side-lobe suppression are constructed respectively; then, the maximal excitation of a polarization directivity coefficient is obtained by a Lagrange multiplier method and is added in the MOPSO algorithm as preference information, an initial population is generated in the vicinity of optimal solutions, and the model is solved by iterative calculation; a convex optimization model of the low side-lobe pattern synthesis is constructed, a convex optimization tool is utilized to solve the corresponding optimal solutions under different threshold constraints, then the three-dimensional array antenna pattern under the low side-lobe constraint is obtained, and therefore the purpose of side-lobe suppression is achieved. According to the side-lobe suppression method for the three-dimensional array antenna pattern based on the improved MOPSO and the convex optimization algorithm, the optimization performance of the algorithms is improved, and the side-lobe suppression problem of the three-dimensional array antenna pattern can be solved efficiently and quickly.

A method of forming an antenna beam with a phased array antenna having an array of antenna elements includes selecting angular directions at which nulls are to be located in an antenna radiation pattern of the phased array antenna, computing a radiation shaping transformation as a function of the selected angular directions, and determining from the radiation shaping transformation an amplitude and phase distribution over the array of antenna elements that forms the antenna beam with nulls of the antenna radiation pattern at the selected angular directions. Computing of the radiation shaping transformation involves constructing a set of vectors corresponding to the selected antenna radiation pattern nulls, and computing a matrix whose product with each of the vectors is zero. The amplitude and phase distribution is determined from the matrix.

Methods and apparatus for antennas, wireless cells and networks are described. Antennas use a shield to provide a shape of coverage, area of coverage, and channel assignment pattern configured for high throughput wireless cells and networks. Diplexers are used to form wireless cells configured for high throughput wireless cells and networks.

A portable communication device (100) has an antenna with predominantly upward antenna radiation patterns at GPS frequencies. The portable communication device (100) includes a housing with a base portion (240) enclosing base portion circuitry (241) and an upper clamshell portion (242) enclosing upper clamshell portion circuitry (243). The portable communication device (100) also includes a hinge assembly (244) coupled to the base portion (240) and the upper clamshell portion (242) for rotatably coupling the upper clamshell portion (242) to the base portion (240) and an antenna element (236) physically coupled to a first side (248) of the upper clamshell portion (242) and electrically coupled to a ground of the upper clamshell portion circuitry (243). The ground of the upper clamshell portion circuitry (243) is electrically connected to a ground of the base portion circuitry (241) by one side of the hinge assembly (244) located closest to a second side (250) of the upper clamshell portion (242) opposite the first side (248).

A diverse wireless channel analysis platform based on antenna radiation directional diagram and a method thereof are disclosed; a transmitting antenna and a receiving antenna are respectively fixed at certain positions in the space and transmits and receives data through different radiation directional diagram of the antenna, the diversity of the antenna radiation directional diagram is used as a sampling space of the wireless transmission channel response on the space domain, and simultaneously high precision parameter estimation algorithm is used for obtaining detailed features of the wireless transmission channel in the directions of incident and exit through a manner of array signal processing, and conclusion and model construction are carried out on the feature of the wireless transmission channel by combining the feature estimation results of the channel on the time domain and time delay domain. The invention eliminates the fuzzy judgment problem of time and space of the traditional channel analysis method and improves the preciseness of channel analysis.

To facilitate GPS hardware selection and evaluate performance of vehicle integrated GPS hardware, including various types of GPS antennas and receivers, within different vehicle operating environments, embodiments of the invention are used to provide a simulator which does not require physical GPS hardware to simulate GPS system performance. Preferably, the simulator randomly generates one or more GPS system link budget variables, within predetermined performance bounds, in order to predict GPS system performance in a specific vehicle operating environment for a given antenna radiation pattern and/or GPS receiver. The simulator employs a Monte Carlo technique to evaluate the GPS system performance based on generated pools of link budget variables.

Several electromagnetic scattering structures are designed to improve antenna radiation patterns. The electromagnetic scattering structure has a conductive layer with certain patterns, and is applied on the radome of the base-station sector antenna. The electromagnetic waves radiating from the antenna therein induce scattering effects, which, together with the electromagnetic diffractions from the rear metal panel of the antenna, can substantially reduce the back lobe and the fields in regions not covered by the antenna. Thus, the antenna radiation patterns are improved so that a lower possibility of co-channel interferences between adjacent base stations can be achieved and therefore better efficiency of the base-station coverage also can be obtained.

An electronic device modifies a schedule of communication frequencies (such as an orthogonal frequency division multiplexing access schedule) by changing the times when subcarriers are used for communication with a set of electronic devices in order to cluster subsets of the set of electronic devices. This clustering may leave the throughput associated with the communication at least approximately unchanged. Then, the electronic device selects, for the subsets, transmit antenna radiation patterns and receive antenna radiation patterns in order to increase the throughputs during transmission and/or receiving.

The present invention is directed to a system and method for extrapolating antenna radiation patterns from a small number of measurements. The present invention is configured to derive an initial estimate based on design information and compare the initial estimate to far-field measurements. The controller is configured to recursively obtain a final estimate wherein a difference between the far-field measurements and the final estimate is less than a predetermined amount. The final estimate represents an extrapolated mapping of the antenna pattern.

The invention discloses an intelligent dual-frequency antenna system including one or more dual-frequency antenna units. Each dual-frequency antenna unit comprises one or more dual-frequency oscillators, a first frequency band reflection unit and a second frequency band reflection unit on the outer side of the horizontally-polarized dual-frequency oscillator, a first frequency band switch unit corresponding to the first frequency band reflection unit, a second frequency band switch unit corresponding to the second frequency band reflection unit, and a control unit. The system controls on/off of each switch unit to change a radiation direction chart of each dual-frequency antenna unit. Compared with the prior art, the system can flexibly control the antenna radiation direction chart.

The embodiment of the invention provides an antenna with the radiation pattern reconfigurable. The antenna with the radiation pattern reconfigurable comprises a Butler matrix module, a phase shift feed network module and an antenna oscillator array; the Butler matrix module is electrically connected with the phase shift feed network module, and the Butler matrix module or the phase shift feed network module is electrically connected with the antenna oscillator array, wherein the Butler matrix module is used for outputting multipath feed signals; the phase shift feed network module is used for regulating the phase of each path of feed signals in the multipath feed signals; the multipath feed signals with the phase adjustable feed a plurality of antenna oscillator units, the beam width of the antenna radiation pattern varies with the phase of the multipath feed signals, and the inclined angle of the antenna radiation pattern varies with the phase of the multipath feed signals. By means of the antenna with the radiation pattern reconfigurable, the antenna can adapt to a building with a complicated layout, and the building can be effectively covered.

A method allows reconfigurable multi-element antennas to select the antenna configuration in MIMO, SIMO and MISO communication system. This selection scheme uses spatial correlation, channel reciprocal condition number, delay spread and average Signal to Noise Ratio (SNR) information to select the antenna radiation pattern at the receiver. Using this approach, it is possible to achieve capacity gains in a multi-element reconfigurable antenna system without modifying the data frame of a conventional wireless communication system. The capacity gain achievable with this configuration selection approach is calculated through numerical simulations using reconfigurable circular patch antennas at the receiver of a MIMO system that employs minimum mean square error receivers for channel estimation. Channel capacity and Bit Error Rate (BER) results show the improvement offered relative to a conventional antenna selection technique for reconfigurable MIMO systems.

A control apparatus for use in a system in which a transmission source apparatus transmits data to a destination apparatus a plurality of times via a plurality of different communication paths comprising at least one path link each formed by two communication apparatuses directly communicating with each other using at least one of a plurality of antenna radiation patterns, the control apparatus including an acquisition unit configured to acquire communication quality information for each antenna radiation pattern of each communication apparatus forming the path links of the communication paths, a selection unit configured to select a plurality of communication paths exhibiting high communication quality based on the communication quality information acquired by the acquisition unit, and a first allocation unit configured to allocate, to a time slot, a path link of the selected communication paths and an associated antenna radiation pattern for each communication apparatus forming the allocated path link.

The invention discloses a broadband low-profile helical antenna with a loaded parasitic patch. The broadband low-profile helical antenna with the loaded parasitic patch comprises a dielectric substrate, a metal grounding plate and a coaxial feed device, wherein the metal grounding plate is printed on the dielectric substrate, the outer surface of the coaxial feed device is connected with the grounding plate, an inner core of the coaxial feed device is connected with the bottom of a spiral metal piece, and a metal patch used for enhancing electromagnetic coupling with the spiral metal piece is arranged above the spiral metal piece. According to the broadband low-profile helical antenna with the loaded parasitic patch, a parasitic metal patch is loaded on the spiral metal piece in an electromagnetic coupling mode so that performances of a patch helical antenna can be effectively improved, profile height of the antenna is reduced, and meanwhile, symmetry of antenna radiation pattern in whole working bandwidth can be improved.

A modal adaptive antenna system that dynamically samples proximity sensors or other sensors to determine the use case for the wireless device and then adjust the antenna radiating mode to optimize communication link performance. The modal adaptive antenna system is capable of modifying the antenna radiation pattern to improve communication link quality along with near-field parameters such as SAR and HAC. An algorithm and look-up table containing pre-measured electrical parameters to include TRP, TIS, and SAR are developed and integrated with hardware which includes an antenna and active components to dynamically modify the radiation pattern of the antenna as well as proximity sensors and or other sensing devices.

The invention provides a direction graph reconfigurable microstrip antenna with ring channel. It adopts the structure of the microstrip rectangle patch antenna. Make several ring channels with different perimeters on the rectangle patch antenna to form a metal patch 14 with new structure, connect the adjoint ring conduction bands or connect the ring conduction band with the small rectangle patch 15 in the middle through the microcomputer electric switches, change the current distribution on the whole metal patch 14 by means of changing the operating states of the microcomputer electric switches (19-30) and then can obtain antenna radiation direction graphs with different main lobe points of the same plane at the same frequency point. Adopting the metal patch 14 realizes the planarization of the antenna and makes the aims of small antenna volume; light weight and easy conformation with the carriers (such as planes) come true. The antenna has simple structure and high use value.