184 results about "Energy leakage" patented technology

The invention discloses a high-precision near-field acoustic holography algorithm adopting a weighted iteration equivalent source method, which is characterized in that a holographic plane H is arranged in a sound source near-field radiation area, and sound pressure PH on the holographic plane H is measured; an equivalent source plane Se is arranged at the side, which is away from the holographic plane H, of an object reconstruction plane T, and equivalent sources are arranged on the equivalent source plane Se; a relation between the sound pressure PH and each equivalent source is established by using a sound pressure transfer matrix between the equivalent source and the holographic plane H; and the source intensity Q of each equivalent source is solved by adopting a new iterative regularization algorithm with a posteriori weighted norm constraint penalty term, and then sound field data on the object reconstruction plane T is calculated by using the solved source intensity Q and the transfer matrix between the equivalent source and the object reconstruction plane T. According to the invention, the source intensity of each equivalent source is precisely solved by using the new iterative regularization algorithm with the posteriori weighted norm constraint penalty term, thereby avoiding source intensity energy leakage caused by a 2-norm penalty term in the Tikhonov regularization process. Compared with conventional equivalent source based near-field acoustic holography, a calculation result acquired by the method disclosed by the invention is more accurate.

The invention discloses channel estimation method and device, which are used for reducing time slot CIR (Channel Impulse Response) energy leakage, enhancing the accuracy of time slot treatment and improving channel estimation property, and are easy to realize. The channel estimation method comprises the steps of: carrying out frequency-domain sideband expansion on a least square (LS) estimation value of channel frequency response, windowing a middle expanded frequency-domain sideband by the channel frequency response subjected to the frequency-domain sideband expansion, then carrying out time-domain denoising and filtering treatment, and removing the expanded frequency-domain sideband for the channel frequency response hnCOMB subjected to time domain denoising to obtain an estimation value of the channel frequency response.

Faraday rotator or isolator with mode stripping ferrules and collimators having fiber pigtailed mode stripping components. An example is a compact Faraday Isolator module employing mode stripping ferrules and mode stripping collimators at the input and / or at the output of a fiber pigtailed Faraday Isolator. Two basic isolator types are a Polarization Independent Faraday isolator and a Polarization Maintaining Faraday isolator. The device is substantially immune to damage due to back-reflection, thermal lensing, energy leakage and absorption. Mode stripped optical energy propagating in the reverse direction is diverted onto a heat absorbing and heat sinking structure, as for example at the input of a compact birefringent wedge-based PI isolator. Alternatively, the optical energy propagating in the reverse direction is angularly refracted away from the forward incident beam path and is coupled into the energy dispersive cladding of the input fiber or the ferrule itself.

The invention discloses a cryptographic-equipment-oriented energy leakage acquisition method and system, belonging to the technical field of information security. The method disclosed by the invention comprises the following steps that: (1) a sampling client-side resolves inputted command information to generate a sampling command sequence and sends the sampling command sequence to a sampling server; (2) the sampling server resolves the sampling command sequence to generate control information and sends the control information to an oscillograph or a cryptographic chip; (3) the cryptographic chip executes the received control information and generates a trigger signal, then, sends the executed result to the sampling server, and sends the trigger signal to the oscillograph; (4) the oscillograph executes the received control information, and carries out energy trace information acquisition on the cryptographic chip according to the trigger signal; and (5) the oscillograph sends acquired energy traces to the sampling client-side through the sampling server. The system disclosed by the invention comprises target equipment, the sampling client-side, the sampling server and the oscillograph. The cryptographic-equipment-oriented energy leakage acquisition method and the cryptographic-equipment-oriented energy leakage acquisition system contribute to the fast, accurate and effective evaluation of the energy analysis attack resistance of a cryptographic algorithm in the physics realization of embedded microprocessing.

A blind carrier frequency offset estimator is based on a single-OFDM-symbol training sequence in multi-user OFDMA uplink. Through multiple access interference modeling and analysis, a virtual user is employed that occupies the all null sub-carriers. By minimizing the energy leakage on the virtual user in term of tentative frequency offsets, the estimator can approach the real frequency offset. The estimator performs only on frequency-domain, simplifies interference calculations, and lowers the rank of the matrix. An iterative computation method is used to approach the real frequency offset.

An RF screen for microwave powered UV lamp systems is provided. The RF screen is formed of a single sheet of conductive material in which a mesh pattern has been formed. The screen includes a non-traditional mesh pattern including individual openings with 3 or more nodes. The RF screen is generally configured to optimize the balance between light transmission and RF energy leakage desired for the particular application. Generally, it is desired that the RF screen has an open area percentage greater than about 80% while limiting RF energy leakage from the microwave powered lamp system to acceptable levels.

The invention belongs to the field of radar technology and communication technology, in particular to a tightly coupled antenna array with wide bandwidth, wide angle and low profile. The antenna arraycomprises a supporting member composed of a supporting plate, a supporting plate frame, a reflecting plate and a feeding joint, and an antenna line composed of a Wilkinson power divider, a feeding balun, a radiation current sheet and a frequency selection surface; The antenna line is laminated by two dielectric copper clad plates, and are divided into four layers: circuit structure layers of theupper and lower layers of an upper layer dielectric plate and circuit structure layers of the upper and lower layers of a lower layer dielectric plate; the first and fourth layers are in a symmetricalradiation structure, the second layer is an empty plate, and the third layer is provided with the power divider and balun. The first and fourth layers are electrically connected through conductive vias to provide a closed environment for the third layer and suppress energy leakage. The radiation current sheet is symmetrically distributed, which can reduce the impedance at the point where the balun is coupled with the current sheet. Frequency selective surface is located on the third layer, which can be used to replace the impedance matching dielectric layer on the current sheet, so that the antenna can be fabricated and installed more easily.