30 results about "Radiation power density" patented technology

The invention discloses a method for calculating the radiation power density of an antenna of a mobile communication base station. The method comprises the steps that a horizontal plane normalization directivity function and a vertical plane normalization directivity function are established, a measuring point away from a vertical plane by the assigned distance is selected for the antenna, the fitting coefficient of the horizontal plane normalization directivity function of the antenna is obtained by obtaining the antenna radiation power data at the measuring point and performing fitting, the final gain value from the antenna of the mobile communication base station to an antenna panel is determined based on the antenna theoretical gain value of the mobile communication base station, a computing model for the radiation power density of the antenna of the base station is established according to the fitting coefficient of the horizontal plane normalization directivity function of the antenna and the finial gain value from the antenna to the antenna panel, and the antenna radiation power density suitable for any azimuth angle can be worked out. The method has the advantages of being high in accuracy and suitable for any azimuth angle.

A method for measuring electromagnetic radiation pattern and gain of radiator using TEM waveguide is disclosed. The method includes the steps of: a) measuring powers of output port of a transverse electric and magnetic (TEM) waveguide by changing arrangements of the radiator located within the TEM waveguide; and b) estimating a radiation power density of the radiator in free space, wherein the radiator is modeled as a dipole moment based on the powers of the output port of the TEM waveguide.

The invention provides a TOF distance measuring system and a movable platform. The TOF distance measuring system comprises a light emitter, a receiver, a controller, and an optical system. The optical system comprises at least one of a first optical signal processing device and a second optical signal processing device. Optical signals emitted by the light emitter are processed by the first optical signal processing device, and then the radiation power density of the optical signals emitted by the light emitter is improved. The optical signals reflected by a target object are processed by the second optical signal processing device, and the intensities of the optical signals reflected by the target object are improved. The radiation power density of the optical signals emitted by the light emitter is improved, and/or the intensities of the optical signals reflected by the target object received by the receiver are improved, and the signal to noise ratio of the TOF distance measuring system is improved, and the target object far away from the TOF distance measuring system is detected by the TOF distance measuring system, and therefore the distance measuring range of the TOF distance measuring system is improved.

The invention relates to a laser fire initiating explosive device optical window in a double-self-focusing lens structure and belongs to the optical window design of laser fire initiating explosive devices. The optical window overcomes the technical defects of the traditional laser fire initiating explosive device optical window in the prior art, the reduction of the laser radiation power density can be avoided, the entrance of proportional reflecting light into a detection optical fiber can also be ensured, and the consistency of the reflectivity of each fire initiating explosive device is improved. The window comprises a laser device, an ignition optical fiber, a detector, a detection optical fiber, a first self-focusing lens and a second self-focusing lens, wherein the laser device is connected with the first self-focusing lens through the ignition optical fiber, the detector is connected with the first self-focusing lens through the detection optical fiber, the first self-focusing lens and the second self-focusing lens are in parallel arrangement, and in addition, optical axes are coaxial. The laser fire initiating explosive device optical window has the advantages that the ignition laser power density is kept, the ignition reliability margin is ensured, in addition, the reflectivity randomness of the optical window is effectively reduced, the quantitative detection of the reflecting light is favorably realized, and the validity of the continuous detection of the optical path is further improved.

The invention relates to a device and method for enhancing the read-write capacity of an RFID tag and an intelligent checking device. The problem that an existing RFID tag is poor in read-write capability is solved. The device enhancing the read-write capacity of the RFID tag comprises at least one RFID reader-writer antenna and at least one RFID read-written tag which are arranged between two mutually parallel reflection plates respectively; the radiation beam direction of the RFID reader-writer antenna is perpendicular to any reflection plate, and the RFID read-written tag is not close to the RFID reader-writer antenna or any reflection plate. The device has the advantages that total reflection is approximatively formed because radiation waves of the read-write antenna are approximatively perpendicular to a metal conductor plate; reflection waves and incident waves are superposed in the forward direction to achieve the enhancing effect, the electromagnetic wave radiation power density is multiplied, the field intensity difference is small, and therefore the tag is easy to read and write; batch dense tags which are close to one another are also successful and fast read and written, and the stability of system acquisition data is improved.

The present invention provides a residual passive intermodulation test method. The residual passive intermodulation test method comprises: performing self calibration of the system for testing so as to satisfy a presetting test requirement; scanning the background in a testing place so as to check and remove other interferences; performing calibration of the radiation power density of the system for testing according to the max radiation power density of the position where a satellite to be measured is located so as to allow the radiation power density of the system for testing to reach the level of the max radiation power density; and sampling and obtaining the max radiation power density of the satellite to be measured at different positions relative to the different positions in the testing field, and correspondingly obtaining different radiation power densities of the system for testing so as to obtain relatively stable radiation power density reading. According to the invention, an appropriate wireless test system is built and is calibrated so as to ensure that the passive intermodulation index of the satellite test environment reaches the requirement of the satellite passive intermodulation test, and therefore, the test result authenticity is ensured and the test error influence is decreased.

The invention discloses a Cerenkov terahertz radiation source based on a multilayer graphene surface plasma wave. The Cerenkov terahertz radiation source comprises multilayer graphene covering a substrate having a buffer layer. The multilayer graphene surface plasma wave energy can be increased by reducing the dielectric constant of the buffer layer and increasing the number of graphene layers. When the dielectric constant of the buffer layer is less than the dielectric constant of the substrate, the surface plasma wave excited by moving electrons can be directly converted into coherent Cherenkov terahertz radiation in the dielectric substrate without wave vector compensation. The radiation power density is increased by the surface plasma waves by two to three orders of magnitude. The Cerenkov terahertz radiation source can be used for developing a coherent high-power radiation source working at room temperature and covering the whole terahertz band.

The embodiment of the invention provides a method and device for judging whether the electromagnetic radiation of a base station exceeds standard, and relates to the field of communications, wherein the base station is classified according to frequency, and then according to the category of the base station, a reasonable radiation power density limiting value is determined. The method adopted by the embodiment of the invention comprises the steps: obtaining the frequency of the base station, and determining the category of the frequency of the base station, wherein the category of the frequency comprises high frequency category and low frequency category; determining a radiation power density limiting value corresponding to the base station according to the category of the frequency of the base station; judging whether the electromagnetic radiation of the base station exceeds standard according to the radiation power density limiting value.

The invention discloses a Cerenkov terahertz radiation source based on cylinder graphene surface plasma wave. The Cerenkov terahertz radiation source completely covers a graphene ribbon of a cylindrical dielectric rod, the cylindrical graphene dielectric rod structure has the 2pai periodicity in a circumference direction, so that the surface plasma wave chromatic dispersion can penetrate through the medium light speed line, the surface plasma wave can be matched with the transmission wave vector in the dielectric, so that the surface plasma wave motivated by the annular electron can be directly converted into the coherent Cerenkov terahertz radiation in the dielectric rod without using the wave vector compensation; the radiation power density is enhanced to two to three order of magnitudeby the surface plasma wave. The Cerenkov terahertz radiation source can be used for developing the radiation source which works at room temperature, has coherence and high power and is capable of covering the whole terahertz waveband.

The invention discloses a method for prolonging the service life of a roller. Alloy powder is sprayed to surface alloy of the turned roller, the alloy powder is melted and combined with a roller base body, and a series of laser heating and fusion alloying points are formed. The alloy powder comprises Cr, Si, Mi, W, mullite and rutile. Under the condition that the laser radiation power density is 104-105 W/cm<2>, heating is carried out, and then quick cooling is carried out at the speed of 103-105 DEG C/s. According to the method, by improving the surface quality and the hardness of the roller, the service life of the roller is prolonged. Thus, roller consumption is greatly reduced, the operating rate of a rolling mill is increased, the workloads for replacing the roller on site are reduced for workers, production cost are reduced for enterprises, and good economic benefits and social benefits can be created.

The invention discloses a sub-array dividing method of a rectification antenna array. The method comprises steps of inputting rectification antenna array feature parameters, rectification channel efficiency parameters, radiation power parameters and sub-array dividing type parameters, acquiring a radiation power density curve, acquiring a rectification channel efficiency curve, acquiring a sub-array rectification efficiency expression formula, building a target function according to the sub-array rectification efficiency, conducting even sub-array division to the rectification antenna array, selecting an optimized design variable according to the sub-array dividing type, acquiring a constraint function according to the sub-array dividing type, building a rectification antenna array sub-array dividing optimization module, solving a rectification antenna array sub-array dividing optimization module, outputting a sub-array dividing scheme, and acquiring each sub-array module unit number of the sub-array dividing scheme. With rectification efficiency as the target, sub-arrays of the rectification antenna array is divided; and maximum of the whole rectification efficiency of the rectification antenna array can be achieved.