96results about How to "Offset interference" patented technology

The invention relates to a system and a method for eliminating common station site interference. The system comprises a first coupler, a transmission unit, an adjustment unit, an offset unit and a detection control unit, wherein the first coupler is used for extracting a signal transmitted by an interference base station as an interference offset signal, and coupling the interference offset signal to the transmission unit; the transmission unit is used for transmitting the interference offset signal to the adjustment unit; the adjustment unit is used for carrying out time delay, amplitude andphase adjustment of the interference offset signal to ensure that the interference offset signal and an interference signal received by a receiver from the interference base station through a wireless path have identical amplitudes and 180-degree phase difference; the offset unit is used for adding the interference offset signal adjusted by the adjustment unit to the interference signal received by the receiver from the interference base station, thereby offsetting the interference signal from the interference base station; and the detection control unit is used for controlling the adjustmentunit to carry out time delay, amplitude and phase adjustment of the interference offset signal according to the interference signal received by the receiver from the interference base station.

The invention relates to a composite electromagnetic shield material with a laminated structure. The laminated structure comprises a magnetic material coating, a metal coating, an adhesive glue coating and a plastic protective coating, wherein one side of the metal coating is jointed with the magnetic material coating, the other side of the metal coating is jointed with one side of the adhesive glue coating, and the other side of the adhesive glue coating is jointed with the plastic protective coating. The invention has the advantages that: firstly, the theory of electromagnetic shield shows that the composition of the metal coating and the magnetic material coating can well shield high-frequency and low-frequency interference; secondly, the technology is simple, the cost is low, and the technical requirements of most electromagnetism compatibility engineering can be satisfied through adjusting the thickness of the metal coating, the thickness and magnetic permeability of soft magnetic material and other parameters; and thirdly, the shield material is easy to adhere outside or inside plastic casings of electrical appliances according to requirements of use after tearing off the plastic protective coating on the adhesive glue coating.

The invention discloses weld joint tracking detection equipment, which comprises a structured light generator for generating structured light, a beam expanding lens, a beam shaping device and an imaging device, wherein the beam expanding lens is positioned at the downstream of the structured light generator and is used for expanding beams of the structured light emitted by the structured light generator; the beam shaping device is positioned at the downstream of the beam expanding lens and is used for shaping the expanded beams to form surface structured light with preset shapes, so that light spots of preset shapes are formed on the weld joints; and the imaging device is used for imaging the light spots of the preset shapes on the weld joints. In the weld joint tracking detection equipment, the butt-jointed weld joints are detected and tracked by adopting the light spots imaged by the surface structured light, and narrow weld joints of which the width is less than 1 millimeter can betracked. The invention also provides a weld joint tracking detection method, which adopts the weld joint tracking detection equipment.

The invention discloses a method and device for notifying and receiving downlink demodulation reference signal initialization configuration parameters. The notifying method is applied to a base station. The downlink demodulation reference signal initialization configuration parameters comprise identifications (IDs) and/or scramble identifications. The notifying method comprises two steps, wherein the first step is that the base station configures N IDs for a terminal according to a high-level signaling exclusive to a user; the second step is that the base station judges whether more than two of the N IDs are identical, and decides to determine the initialization value of a downlink DMRS sequence in one of the following modes according to the judging result; the scramble identification nSCID and the ID used for determining the initialization value of the downlink DMRS sequence are sent to the terminal. By means of the method and device for notifying and receiving the downlink demodulation reference signal initialization configuration parameters, the switchover between dynamic orthogonality and interference randomization of the interference of one UE to other UE can be realized, and therefore the effects of offsetting the interference of users, improving the accuracy of data acceptance and enabling cells to split and gain under the Scenario 4 are achieved.

The invention discloses a crack detection method based on laser scanning thermal imaging. The method comprises the following steps: scanning a heated sample surface by relative movement of the line laser and the sample; adopting a thermal imager for recording the condition of temperature change of the sample surface in real time; adopting a computer for acquiring the heat signals on all the points of the sample surface according to the temperature distributions at different moments in a thermal image, aligning the time axis of the heat signals and cutting and then adopting an adjacent heat signal comparing method for imaging the cracks. According to the invention, the signal-to-noise ratio of the crack detection can be effectively promoted and tiny cracks on the detected piece surface can be detected.

The invention discloses a single-carrier frequency domain equalization realization method and a single-carrier frequency domain equalization realization system. Date frames employed in each step respectively comprise a training sequence part and a data transmission part; the data transmission part is behind the training sequence part and composed of an UW (Ultrasonic Wave) and a data block, and the UW is prior to the data block; the data block comprises multiple continuous FFT (Fast Fourier Transform Algorithm) blocks, any one of FFT blocks is respectively composed of one data and one UW, and the data is prior to the UW; the training sequence part is prior to the data transmission part and composed of the UW and a long PN (Performance number) sequence for frame synchronization detection and channel estimation, the long PN sequence is composed of the integral multiple of the UW, and the length of the long PN sequence is the same as the length of one data in the data block. According to the method and the system, the number of operation is reduced when the high precision is ensured.

The invention discloses a balance car steering control method and a balance car. The balance car includes a car body, and a pedal assembly arranged on the car body, and the pedal assembly includes pressure sensors corresponding to the bipods respectively; The foot pressure difference and the driver's weight; control the steering of the balance car according to the ratio of the pressure difference between the feet and the weight. The invention can realize precise steering without a rotating shaft.

The invention relates to a three-terminal flux gate sensor that is made up of coiling a set of winding on two I shaped frames, and one starting end of the winding is connected to the terminal end of the other winding to form center end to used as the measuring end and feedback end of the sensor. The two other ends of the winding are used as the prompting end. The three terminals are sintered on PCB, and the two I shaped frame winding are cementing to form II shaped frame winding. Coiling 2-4 circles of permalloy to the center of two I shaped frames to make raceway magnetic core, and packaging the II shaped frame magnetic winding and PCB into non magnetic aluminum box. The invention has simple structure, and easy to manufactured. It could counteract the influence of distributed capacitance, interference signal and temperature drifting. The accuracy and resolution of the sensor are improved. And the power consumption and temperature coefficient would be decreased.

The invention discloses a synchronous frame encoding method, which comprises the following steps: A, a synchronization sequence and an index number of a synchronous frame are generated; B, a check bit is formed in accordance with the generated synchronization sequence and the index number; C, the synchronous frame including the check bit is assembled in accordance with the synchronization sequence, the index number and the check bit and is then transmitted. The invention also discloses a synchronous frame decoding method, a synchronous frame encoder and a synchronous frame decoder. The inventive proposal is able to make the synchronization sequence and the index number of the synchronous frame process certain error correction capability, thereby effectively offsetting the various interference in the wireless communication channel; the invention is able to make the receiver check the error to the synchronous frame, thereby greatly improving the reliability and effectiveness of the communication.

The invention provides an uplink transmission method, a station, a communication system, and a management real object. The method comprises a step that a station STA generates an uplink frame which comprises RUT (robust uplink transmission) indication information. When the value of the RUT indication information is a first value, it indicates that an associated access point A-AP associated with the station STA and a coordinative access point C-AP in coordinative relation with the associated access point A-AP receive the uplink frame and carry out the RUT processing of the uplink frame; when the value of the RUT indication information is a second value, it just indicates that the associated access point A-AP associated with the station STA receives the uplink frame and carries out the non-RUT processing of the uplink frame. The method also comprises a step that the station STA transmits the uplink frame.

The invention provides an earphone capable of automatically adjusting volume and a method for automatically adjusting the volume of the earphone and belongs to the field of earphones. The earphone capable of automatically adjusting the volume comprises an automatic volume adjusting module and a wireless module, wherein the wireless module is connected with audio equipment, and the automatic volume adjusting module is used for automatically acquiring an external noise signal and controlling a loudspeaker of the earphone to change the volume in real time. The method for automatically adjusting the volume of the earphone has the advantages that different voice registers are set, voice register matching is carried out on the external noise signal, the external noise signal is compared with a high pitch threshold and a low pitch threshold of the external noise signal in the range of the voice register, automatic increase and decrease of the volume of the loudspeaker are realized, control is accurate, user experience is better, and popularization is facilitated.

The invention discloses a GFDM/CDMA hybrid multiple access wireless access method so that the interference between sub carriers of the GFDM can be eliminated. The method is characterized in that a spread slotted ALOHA is introduced in a generalized frequency division multiplexing (GFDM)/code division multiple access (CDMA) hybrid multiple-access wireless access system of a multi-carrier transmitter, so that a problem that the interference is caused between users using adjacent sub carriers is solved. After the user completes time-frequency synchronization of a base station, all users send uplink data with base station arrival times being all time slot starting times randomly; the K sub carriers are employed and each sub carrier is able to carry a GFDM system with the symbol number being Mto number the sub carriers; and when the users send data, PN sequences are added between the adjacent sub carriers to carry out spread spectrum, the same PN1 is used for sub carriers with odd numbers,and the same PN2 s used for sub carriers with even numbers, so that the interference between the non-orthogonal sub carriers is eliminated.

The invention provides a high-frequency broadband frequency hopping signal generation device based on a photon technology. The device comprises a laser, a low-frequency frequency hopping signal, a dual-polarization quadrature phase shift keying modulator DPQPSKM, a polarization controller, an optical circulator, a polarization beam splitter, a radio frequency local oscillator signal, an optical frequency shift module, an analyzer and a photoelectric detector. An optical modulator is used for carrying out electro-optical modulation on optical carriers and low-frequency frequency hopping signals output by a laser source to generate two paths of polarized orthogonal dual-wavelength optical signals, interference occurs after the two paths of polarized orthogonal dual-wavelength optical signals pass through a polarization controller, two paths of polarized orthogonal single-frequency optical signals are obtained, the two paths of polarized orthogonal single-frequency optical signals enter a Sagnac ring structure in the clockwise/anticlockwise transmission direction respectively, and single-frequency optical signal of the forward input optical frequency shift module is modulated to generate frequency shift; and the signals are polarized and combined by a polarization analyzer and then enter a detector for beat frequency, so that frequency multiplication and up-conversion operations on the low-frequency frequency hopping signals are realized. According to the invention, the working frequency band of the low-frequency frequency hopping signal is improved to a high-frequency domain by using an optical means, the working bandwidth is multiplied, the system control is flexible, and the tuning range is large.

The invention discloses a novel method for analyzing a leaked current of a metal oxide lightning arrester, and the method comprises the steps: firstly carrying out 10-cycle windowing, meeting the IEC standard, of a discrete sampling value (shown in the description) of a power grid signal; secondly executing nonsynchronous Hanning windowing; thirdly multiplying a frequency spectrum value at a corresponding spectral line k after DFT/FFT transformation by a twiddle phase factor (shown in the description) for two times; fourthly carrying out the superposition of amplitude vectors at frequency points obtained after transformation, so as to obtain the accurate values of the frequency, amplitude and phase parameters of the lightning arrester. The method can eliminate the picket fence effect and inhibit frequency spectrum leakage during fundamental frequency nonsynchronous sampling through the superposition of amplitude vectors at frequency points obtained after twiddle factor transformation, eliminates the impact from instantaneous large disturbances, and avoids errors appearing in a conventional FFT algorithm during nonsynchronous sampling or instantaneous large disturbances.

The invention provides an offshore wind power operation device and a balancing device thereof. The balancing device comprises a multi-axis parallel robot, a tilt sensor, an acceleration sensor and a controller, wherein the multi-axis parallel robot comprises a static platform, a moving platform, a plurality of telescopic connecting rods and a plurality of driving mechanisms; the plurality of connecting rods are used for connecting the static platform with the moving platform; each of the plurality of driving mechanisms is respectively used for driving the corresponding connecting rod to telescope; the tilt sensor is used for measuring attitude parameters of the moving platform; the acceleration sensor is used for measuring position parameters of the moving platform; the controller is usedfor acquiring the attitude parameters and the position parameters, determining length adjustment values of the connecting rods according to the attitude parameters, the position parameters, attitude given values and position given values and controlling the connecting rods of the driving mechanisms to telescope according to the length adjustment values. The balancing device performs real-time position and attitude adjustment to maximize the offset of wave interference.

The invention discloses an active field compensation type digital ultralow frequency electromagnetic sensor, consisting of a sensor seal head, an SD card groove, a collection instrument cabin, a cushion block, an induction coil group, a sensor housing, a sensor shielding layer, and a magnetic core rod support. The invention utilizes a high performance CPU as a main controller, realizes the high accuracy data collection under a condition of low frequency and weak signal and stores the collected data into the SD card. The CPU starts up the active compensation system according to the real-time measurement temperature and vibration data in the data collection process, performs real-time automatic compensation on the collected signal, and effectively overcomes the affect on the test data due to the environment temperature and vibration. The invention has advantages of compensating the capability width and digitalized output.

The invention provides a multi-input and multi-output antenna system, which comprises a first antenna unit and a second antenna unit. The first antenna unit includes a first transmitter, a first receiver, a first circulator, a first compensation circuit, a second compensation circuit, a first antenna and a first electronic switch. The second antenna unit comprises a second transmitter, a second receiver, a second circulator, a third compensation circuit, a fourth compensation circuit, a second antenna and a second electronic switch. The first compensation circuit and the third compensation circuit are used for resisting and reducing leakage signals. The second compensation circuit and the fourth compensation circuit are used for resisting and reducing near-field interference signals. The multi-input and multi-output antenna system can effectively resist and reduce the noise.

The invention provides a current detection error compensation method and circuit in a voltage drop type power level circuit, which samples and offsets a voltage and is fed back to a current sampling module as a feedback signal. The cancellation voltage is used as an input signal to compensate and cancel the interference signal caused by the parasitic inductance on the power MOS device. The cancellation voltage is fed back to the current sampling module as the feedback signal, which can be used as the input signal compensation to offset the interference caused by the parasitic inductance of thepower level circuit, so as to obtain more accurate current zero-crossing detection signals and excessive current signals.

The invention relates to a path tracking device and method for a farmland operation machine. The device includes an Android upper computer and a lower computer module which are connected through a Bluetooth module. The lower computer module comprises a single-chip microcomputer, a geomagnetic sensor, a DGPS module, the Bluetooth module, a Zigbee module, a Flash memory and a power module; the lower computer module is used for receiving and storing path information sent by the Android upper computer; a planned path starting point serves as a first approaching point Q, the farmland operation machine is driven to be close to the Q point, after the farmland operation machine reaches the path starting point, a second approaching point of the farmland operation machine is found by drawing a circle in a neighbor region, and by repeating the motion continually, tracking of the whole path is achieved. The device allows the farmland operation machine to conduct accurate tracking on the planned path, the labor intensity of farming personnel in a traditional mode is greatly reduced, and the agricultural production efficiency is improved.

The invention discloses an anti-interference tracking control design method based on T-S fuzzy interference modeling in the technical field of automatic control. The method comprises the following steps: 1, establishing a system state equation containing external interference; 2, establishing an interference model through a T-S fuzzy model, designing a PI tracking controller, and constructing a composite system; 3, designing a disturbance observer; 4, designing a compound control system based on the disturbance observer and the PI tracking controller; and 5, solving the control gain and the observer gain based on a convex optimization algorithm. The method realizes the effective suppression of system interference and dynamic tracking of system output, and having good robustness and high stability.

The invention discloses a vertical rotor system with an active vibration suppression function and an active vibration suppression method thereof. The vertical rotor system is composed of a driven rotor main shaft, a bearing box with a spherical hinge support, a variable rigidity and damping electromagnetic bearing, a sensor, a measuring transmitter, a controller and a working section, wherein thedriven rotor main shaft is used for generating rotating mechanical energy to drive the working section to do work, the working section can be arranged at the top end or the bottom end of the driven rotor main shaft according to the working requirement of the rotor system, a bearing in the bearing box is used for supporting a rotor, the spherical hinge support is used for vibration reduction, and the sensor, the measuring transmitter, the controller and the variable rigidity and damping electromagnetic bearing forms an active vibration suppression system which is used for realizing active vibration suppression of the rotor subsystem. By detecting the vibration of the rotor, analyzing the vibration of the rotor to generate a control signal to adjust the rigidity and damping of the electromagnetic bearing, thereby outputting the corresponding damping force, and achieving active suppression of vibration of the vertical rotor system.