97results about How to "Maximized ratio" patented technology

Method and Apparatus thereof for coordinating a joint transmission between a plurality of cooperative access nodes serving a plurality of user terminals in a mobile communications system, including the steps of: receiving channel information by said access nodes from user terminals that are being served by said access nodes; exchanging between said access nodes of said received channel information thus ensuring that all channel information is distributed to all cooperative access nodes; processing all received channel information by each one of said access nodes, and determining by said access nodes using said processed channel information, of a channel estimation for said joint transmission.

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.

An armature for an electric motor is constructed from a pair of precision machined copper plates cut in a pattern to produce a series of axially extending surface conductive bands with each band separated from the other by an insulated cutout. The precision machined plates are rolled to form two telescoping, hollow cylinders with each cylinder having a pattern of conductive bands representing a half-electric circuit. The outer surface of the inner cylinder is wrapped with several layers of fiberglass strands for structural stability and insulation. The fiberglass wrapped inner cylinder is telescoped inside the outer cylinder. The outer surface of the telescoped structure is also wrapped with several layers of fiberglass strands for structural stability. The conductive bands from the outer cylinder being the near mirror image of the conductive bands of the inner cylinder are helically coupled to form a complete electrical circuit. The resulting tubular structure is encapsulated in a potting material for further structural stability and insulation. The result is a freestanding ironless core inductive armature coil for a DC motor with brushes. The armature also has a commutator, which is mounted at one end of the coil and is in electrical contact with the helically coupled conductive bands. An insulated flywheel and shaft assembly is mounted inside the coil with the flywheel behind the commutator for motor mounting and operation.

A laser device which can be used as a light source for an exposure device, can be downsized, and is easy to maintain. A laser beam (LB6) emitted from a DFB (Distributed feedback) semiconductor laser, for example, and amplified by an optical fiber amplifier is passed through non-linear optical crystals (502, 503, 504) to be sequentially doubled in frequency to thereby generate an ultraviolet-region laser beam (LB5) consisting of an octuple wave. A GdYCOB, that is, Gd_xY_1−xCa₄O(BO₃)₃ crystal (0≦×≦1) is used for the non-linear optical crystal (503) for a double wave-to-quadruple wave conversion, and a KAB, that is, K₂Al₂B₄O₇ crystal for the non-linear optical crystal (504) for a quadruple wave-to-octuple wave conversion. The non-linear optical crystals (502-504) are all fine-tuned in phase match angle by temperature controllers (521-523) respectively.

The invention relates to an audio processing system for processing an input sound to an output sound. The invention further relates to a method of estimating a feedback transfer function in an audio processing system. The object of the present invention is to provide an alternative scheme for minimizing feedback in audio processing systems. The problem is solved in that the audio processing system comprises an input transducer for converting an input sound to an electric input signal and defining an input side, an output transducer for converting a processed electric output signal to an output sound and defining an output side, a forward path being defined between the input transducer and the output transducer, and comprising a signal processing unit adapted for processing an SPU-input signal originating from the electric input signal and to provide a processed SPU-output signal, and an electric feedback loop from the output side to the input side comprising a feedback path estimation unit for estimating an acoustic feedback transfer function from the output transducer to the input transducer, and a enhancement unit for estimating noise-like signal components in the electric signal of the forward path and providing a noise signal estimate output, wherein the feedback path estimation unit is adapted to use the noise signal estimate output in the estimation of the acoustic feedback transfer function. This has the advantage of providing an adaptive feedback cancellation system which is robust in situations with a high degree of correlation between the output signal and the input signal of an audio processing system, e.g. a listening device. The invention may e.g. be used in public address systems, entertainment systems, hearing aids, head sets, mobile phones, wearable/portable communication devices, etc.

A high-directivity transponder system uses a dual system of a retrodirective array transmitting a data signal peak toward an interrogator source, and a self-null-steering array transmitting a null toward the interrogator source and a jamming signal elsewhere, resulting in high S/N reception at the interrogator source and avoidance of interception. Integrating modulators would allow each array to transmit different data while the spectra of the transmitted signals are identical, thus disabling interception. The system enables secure point-to-point communications and can be used for short-distance wireless data transmission systems such as wireless LAN and RFID servers. As another aspect, self-steering signal transmission is employed for randomly oriented satellites using circularly polarized, two-dimensional retrodirective arrays. Quadruple subharmonic mixing is used as an effective means of achieving phase conjugation when a high-frequency LO is not feasible or inapplicable. These features may be used for small-satellite communications, secure tactical communications, search and rescue, enemy location fixing and tracking, UAV command and control, forest fire detection, marine-based tracking, and many other applications requiring secure communications with high signal directivity.

Provided is an exhaust emission control device for an internal combustion engine capable of preventing NOx purification performance from degrading according to the operating condition. The exhaust emission control device comprises an NOx purification catalyst for adsorbing or occluding NOx in exhaust emissions and reducing the NOx, which is provided in an exhaust pipe (4), a catalyst converter (31) for continuously reducing the NOx in the exhaust emissions by using a reducing gas, which is provided in the exhaust pipe (4), a fuel reformer (50) for reforming fuel to manufacture a reformed gas containing hydrogen and carbon monoxide and supplying the reformed gas as the reducing gas from an introduction port (14) provided on the upstream side of the NOx purification catalyst (33) and the catalyst converter (31) of the exhaust pipe (4), which is provided separately from the exhaust pipe (4), an operating condition detecting means for detecting the operating condition of an engine, and an enriching means (40) for enriching the exhaust air-fuel ratio. The enriching means enriches the exhaust air-fuel ratio by supplying the reducing gas into the exhaust pipe (4) by using the fuel reformer (50) when the operating condition detected by the operating condition detecting means is a high-load operating condition.

The present disclosure is directed to a system and method for optimizing operation of a wind turbine. The method includes providing a voltage regulator between a power grid and the wind turbine. The voltage regulator is configured to control at least one voltage condition of the wind turbine. Another step includes monitoring, via one or more sensors, at least one operating condition and at least one voltage condition of the wind turbine. The method also includes comparing, via a controller, at least one of the operating condition or the voltage condition with a predetermined threshold to determine a margin-to-threshold ratio. Thus, a further step includes controlling the voltage regulator based on the comparison so as to maximize the margin-to-threshold ratio.

Novel femoral implants for use in hip arthroplasty are described and illustrated. The femoral implant comprise a stem and neck portion, with the neck portion having a novel configuration that provides for improved range in motion for the prosthesis without compromising strength of the implant.

A method of making CNT films is described in which the film is washed with a mild acid treatment. The method generates a CNT film that is not sensitive to moisture or fluctuations in moisture. The method involves the use of anionic polysaccharides or anionic glycosaminoglycans such as hyaluronic acid, sodium salt, as aqueous dispersing agents and their modification to a hydrophobic matrix after deposition. In the course of conducting the work described here, we made the surprising discovery that washing with an aqueous acidic solution resulted in a decrease in resistance through the material. The invention also includes CNT composites made by the inventive methods and a CNT composite comprising CNTs and anionic polysaccharides or anionic glycosaminoglycans further characterized by a low cationic content and a high conductivity and/or small CNT particle size as measured by SEM.

A stepping motor includes: a stator which includes a cup-like first (outer) yoke having a plurality of notches formed at its bottom plate, a second (inner) yoke, and a bobbin having a coil wound therearound and housed in the annular hollow space formed by the first and second yokes; and a pair of bearings each of which includes a hollow-cylindrical main body and a flange structure having a plurality of protrusions, and is attached to the stator such that the protrusions engage with the notches of the first yoke thereby preventing the bearing from rotating relative to the first yoke, and such that the protrusions make contact with a flange of the bobbin thereby precisely positioning the bearing relative to the first yoke with respect to the axial direction, which prohibits any portions of the bearing from protruding axially outwardly beyond the bottom plate of the first yoke.

The present invention relates to a composition comprising at least one poly(arylene ether ketone) powder suitable for laser sintering and also to the process which makes it possible to obtain it, minimizing the amount by weight of remaining non-sintered powder after production of the part by sintering.