1552 results about "Fixed Beam" patented technology

A method and system are disclosed that can be applied to achieve high-throughput in a WLAN. Central to the present invention is the use of an SDMA compatible multi-beam antenna system by a WLAN access point. A system based on two types of antennas-dynamic beam forming and fixed beam antennas—is described. A mechanism and protocol are described that implement simultaneous transmissions with respect to an SDMA compatible access point and thereby improve spectral efficiency, and by extension achieve higher throughput. Based on the recognition that current WLAN MAC has major limitations in throughput, certain MAC extensions (that can be applied independently of SDMA) are described. Also disclosed are power-saving and power control techniques that improve battery performance and contribute to a reduction in station size, and a means of reducing channel interference. The present invention also deals with the problem of backward compatibility with conventional devices that implement the protocol that is a subset covered by the present invention.

An OFDMA communication system is provided that schedules partial usage of subchannels (PUSC) major groups by assigning a beam matrix of a plurality of beam matrices to each major group of multiple PUSC major groups, receiving an uplink signal from each user equipment of multiple users equipment, which uplink signal provides an indication of a channel response associated with the user equipment, determining, for each user equipment of the multiple users equipment and based on the indication of channel quality received from the user equipment, a beam matrix and major group to which to assign the user equipment, and based on the determination of a beam matrix and major group to which to assign each user equipment of the multiple users equipment, assigning two or more users equipment of the multiple users equipment to a same beam matrix and major group during a same time slot.

The present invention generally relates to the field of wireless communication systems. It particularly refers to a spatial diversity transmitter (110) and a spatial diversity receiver (120) in a wireless multiple-input multiple-output (MIMO) spatial multiplexing system as well as a corresponding method for wirelessly transmitting and receiving modulated RF signals via multiple wireless signal propagation paths (P_l) of a multipath fading channel in a way that correlation between the MEMO channel components are reduced and/or the signal to interference plus noise ratio (SINR) is increased which hence result in an improved bit error rate (BER) or packet error rate (PER) performance of said wireless MIMO spatial multiplexing system. On the receiver side, for example, this is achieved by controlling at least one antenna switching and/or combining means (121a′+b′) to select a specific combination of different fixed beam antennas (121a+b) from each receiver-resident antenna array. According to the invention, said selection is based on estimated values of the channel impulse responses (h_l(τ_l, t)) for said signal propagation paths (P_l). An antenna beam selection control means (129) is configured for selecting a specific antenna beam combination so as to maximize the average signal-to-interference-plus-noise ratios ( γ_l) of RF signals (r_l(τ_l, t, φ_l)) received via said multiple wireless signal propagation paths (P_l) and/or to minimize the correlation coefficients (ρ_{r<sub2>l1</sub2>r<sub2>l2</sub2>}(t)) indicating the correlations of different pairs of these RF signals (r_l1(τ_l1, t, φ_l1) and r_l2(τ_l2, t, φ_l2)).

Thereby, each fixed beam antenna (121a+b) of the receiver-resident antenna arrays has a distinct radiation pattern with a different beam center and/or beam width in the azimuth and/or elevation plane, wherein a superposition of all these radiation patterns may cover all possible azimuthal (φ) and/or elevational angles of arrival (θ) of an RF signal (s(t)).

For compensating detected multipath fades in the channel amplitude response (|H_l(f, t)|) of at least one signal propagation path (P_l) between the spatial diversity transmitter (110) and the spatial diversity receiver (120), a receiver-resident channel estimation and/or equalization circuitry (124, 128) is applied.

A transmit diversity apparatus and method are provided for adaptively providing a transmit diversity gain or a beamforming gain depending on changes in a radio channel undergoing multipath fading in a mobile communication system using multiple antennas. A transmitter forms as many fixed beams as the number of transmit antennas and a receiver selects a fixed beam having relatively high power among received fixed beams or linearly combines the received fixed beams. This common eigen space transmit diversity scheme improves the link performance between the transmitter and the receiver.

The invention discloses an opening current transformer capable of being installed in a powered-on mode. A shell is divided into two oppositely-connected half cylinders used as a movable semicircular shell body and a fixed semicircular shell body. The two shell bodies are hinged at one oppositely-connected position. A longitudinally-extending movable beam is arranged at an opening of the movable semicircular shell body. A longitudinally-extending fixed beam is arranged at an opening of the fixed semicircular shell body. The fixed beam and the movable beam are blocky bodies and make contact with each other when the two shell bodies are oppositely connected. The contact face of the movable beam and the contact face of the fixed beam are each provided with a longitudinally-extending notch. An upper piercing wire card is arranged in the notch of the movable beam. A lower piercing wire card is arranged in the notch of the fixed beam. The upper piercing wire card and the lower piercing wire card are oppositely connected to form a wire holding hole. The upper piercing wire card and the lower piercing wire card are each provided with metal teeth piercing a bus metal core. The opening current transformer further comprises an opening and closing mechanism making the upper piercing wire card and the lower piercing wire card opened or closed. The opening current transformer is reliable in insulation, capable of being firmly installed on a bus, and capable of being widely applied to occasions for measuring primary current and temperature of the bus.

A perimeter clip attached to a wall molding that supports a beam in a suspended ceiling intended to survive seismic disturbances. The clip is capable, during an earthquake, of permitting an end of a beam at one end of a connected line of beams, in a grid, to slide while being supported in the clip, or, in the alternative, to secure an end of a beam to the wall molding.

The invention relates to an adjustable multi-hob rock cutting fragmentation test device for the field of tunnel project. Being characterized in that the soil warehouse is provided on a guiding track achieving the vertical movement by the vertically-moving hydraulic cylinder; the soil warehouse is provided on the soil warehouse supporting base for achieving the transverse movement by the transverse hydraulic cylinder fixed on the soil warehouse base; the soil warehouse has the rock soil samples; two sides of the soil warehouse are provided with four pillars leaning against the beams and forming a rectangular frame structure. The lower position of the fixed beams of the vertical movement of two synchronized hydraulic cylinders for the realization of the vertical plate hob feed, vertical hydraulic cylinder mounting bracket for the following connection hob, for the realization of more than the fixed plate hob; mounting bracket Three-axis with the following sensors, hob plate connected to the force sensor in the bottom three of the hob seat, using industrial computer, data acquisition cards, the pressure of traffic and other sensors, such as high-speed digital camera system to test the disk-shaped roll knife load rock, broken rock and soil characteristics.

A three-dimensional micro electro-mechanical (MEMS) variable capacitor is described wherein movable comb electrodes of opposing polarity are fabricated simultaneously on the same substrate are independently actuated. These electrodes are formed in an interdigitated fashion to maximize the capacitance of the device. The electrodes are jointly or individually actuated. A separate actuation electrode and a ground plane electrode actuate the movable electrodes. The voltage potential between the two electrodes provides a primary mode of operation of the device. The variation of the sidewall overlap area between the interdigitated fingers provides the expected capacitance tuning of the device. The interdigitated electrodes can also be attached on both ends to form fixed-fixed beams. The stiffness of the electrodes is reduced by utilizing thin support structures at the ends of the electrodes. The three dimensional aspect of the device avails large surface area. Large capacitance variation and tuning ranges are obtained by independent actuation of the electrode fingers. A plurality of modes of operation of the device provides wide flexibility and greater performance advantage for the device. Upon fabrication of the device, a separate substrate with etched dielectric is used to encapsulated the device. The MEMS device is then completely encapsulated, requiring no additional packaging of the device. Further, since alignment and bonding can be done on a wafer scale, an improved device yield is obtained at a lower cost.

To suppress adverse effects caused by side lobes of an antenna array when an AWV to be used for communication is determined based on a transmission/reception result of a training signal. A first transceiver generates a fixed beam pattern and transmits a training signal. In that state, a second transceiver receives the training signal while scanning for the main beam direction, and thereby determines a plurality of direction of arrivals (DOAs). Next, the second transceiver receives the training signal in a state where the signal receptions from the plurality of DODs are restricted one by one (e.g., a null direction or a direction close to the null direction is fixed in the DOA), and calculates the change of the signal characteristics from that obtained in the first reception. The transceivers obtain and use at least one AWV having the main beam direction or a sub-beam direction close to the main beam pointing to one of the plurality of DOAs except for the DOA for which the change is lower than a predefined threshold.

The present invention relates to antenna architectures and methods on re-configurable multi-element antennas via feed re-positioning for various optimized radiation contours, including beam forming (or shaping) and/or null steering on contoured beams, spot beams, and orthogonal beams. The feed re-positioning techniques can also be used in radiation pattern optimization processing during antennas designing phases for fixed beams. The techniques are applicable for satellite communications. For satellite antennas, the beam shaping capability via element repositioning can be utilized for (1) optimized geometries on satellite antennas for given desired coverage areas, (2) re-optimizing radiation contours for reconfigurable antenna on board satellites in operation, (3) additional flexibility for satellite antennas using ground based beam forming (GBBF). As to satellite ground terminals, the same techniques are applicable for both fixed and mobile satellite terminals featuring either single beam or multiple beams. For fixed terminals, are applicable for terrestrial based communications; such as retrofitting existing antennas eliminating interference radiations coming from fixed or slow varying directions.

One fixed narrow beam and one sector beam are generated by an antenna array. Multiple fixed narrow beams are realized by shaping technique of simulating fixed beams and using shaping network (Butler array) of fixed narrow beams. A sector beam covering whole sector is formed through controlling initial phase of beam at Butler array side by using phasing adjustment device. Signal energy of sector beams at side of each component of antenna array is equal or approximately equal. Thus, amplitude of transmitted signal of each component of antenna array is lowered.

The bionic mechanical jellyfish consists of a power system comprising four electromagnet devices, a driving system comprising four baffles and two return springs, a water jetting system comprising two leather bags, two water inlet pipes and four water outlet pipes, and a fixing rack comprising a right and a left fixing beam. The present invention has no noise, complete functions, simple structure, high work efficiency, low cost and other advantages.

A satellite system includes a satellite operating in an orbit around the Earth and a satellite operating in another orbit around the Earth. The satellite points a fixed beam at least temporarily to a zone above the Earth's surface through which the satellite passes.

The invention relates to a micro electric mechanical microwave frequency checker, and a relative production, with simple structure, small amplitude of measuring signal, non direct-current power consumption, and easy integration. The checker uses gallium arsenide as a liner (1) arranged with a power distributor (a), a power synthesizer (b), a coplane waveguide line (e), and a fixing beam structure (c), wherein the object signal via the power distributor (a) generates two signals, to form an object signal and another object signal (Us1-Us2), the object signal Us1 is connected with the third port of the power synthesizer (b), the object signal Us2 via a section of a CPW line is connected to the second port of the synthesizer (b) in which port to obtain a first signal via the fixing beam structure (c) to obtain the phase shift phi of the microwave signal on the line with fixed length.

The invention relates to a microelectronic mechanical microwave frequency detector and a preparation method thereof. The microelectronic mechanical microwave frequency detector has simple structure, can measure unknown microwave signals, has large amplitude range of the measurement signals, can avoid consuming direct current power, and is easy to be integrated. The microelectronic mechanical microwave frequency detector adopts a gallium arsenide substrate provided with a 1-to-3 power distributor (a), a coplanar wave guide transmission line (b), a 2-to-1 power distributor (c), a fixing beam structure (d) and a thermocouple structure (e), thereby forming the microelectronic mechanical microwave frequency detector.

A noise suppression system includes plural microphones, a fixed beam former, a blocking matrix, plural adaptive filters, and a direction of arrival circuit coupled to the adaptive filters that prevents the filters from adapting in the presence of a signal in the look direction. The direction of arrival circuit causes the filters to adapt more quickly in the absence of a signal in the look direction. A pair of adjustable gain circuits is coupled to each microphone. A first adjustable gain circuit from each pair is calibrated during the presence of a desired signal and a second adjustable gain circuit from each pair is calibrated during the presence of an interfering signal. A fixed null-forming circuit is coupled to a first pair of variable gain circuits and an adaptive null forming circuit is coupled to a second pair of adjustable gain circuits. The ratio of the gains of the null forming circuits is used as a control signal. Successive ratios are averaged with a variable smoothing constant and a control signal is derived from the averaged ratios.

A near-field radar apparatus includes a fixed beam planar radar antenna and a radiation pattern adaptation device disposed substantially at the near-field boundary of the antenna. The adaptation device comprises a plurality of dielectric elements that individually constitute or approximate different surface portions of an idealized quasi-spherical or quasi-cylindrical radome reflector. The dielectric elements can be maintained physically separate or combined about the diffraction point of the antenna to form a single dielectric element. The dielectric elements may be mounted on a radome that is otherwise transparent to the radiation pattern, or otherwise suspended at or near the near-field boundary of the antenna.

A radar includes fixed beam radar transmitter and receiver antennae that utilize mixed polarization to optimize the object detection field-of-view through an intervening plastic fascia. The transmitter antenna transmits radar energy with slant polarization, a first receiver antenna designed for short-range wide-angle object detection passes only horizontally polarized radar energy, and a second receiver antenna designed for long-range narrow-angle object detection passes only vertically polarized radar energy.

The invention discloses a direct drive type hoist with a boosting caliper brake. The hoist comprises a vertical shaft, a cage, a cage rack, the boosting caliper brake, a safety gear and a positioning mechanism, wherein a fixed beam is arranged on an inner wall mounting base of the vertical shaft; a hoisting permanent magnet linear motor is arranged between the fixed beam and the cage rack; the boosting caliper brake is arranged on the cage rack or the cage; and a brake boosting mechanism and a drive boosting mechanism are arranged on the brake. Compared with those of the conventional identical or similar brakes, the specification, dimension and weight of a push mechanism such as springs are greatly reduced, the braking force and the driving force are increased by one to two orders of magnitude compared with those of common boost-free brakes, and the cage accurately and reliably brakes. The positioning mechanism is arranged between the inner wall of the shaft and the cage. By adopting the scheme of the positioning mechanism and the hoisting linear motor with a slender structure, the variation of a working air gap of the motor is controlled within an engineering allowed band, normal attraction force in unit length is greatly reduced, stress concentration is avoided, and the cage stably operates.