206 results about "Random switching" patented technology

A reconfigurable baseband filter for use in a multimode communication system is disclosed. One or more filter elements can each be configured as a plurality of sub-elements. The value of each of the filter elements can be varied by switching between at least two of the plurality of sub-elements. Switching noise within a desired passband can be reduced by switching at a rate that is greater than the desired passband. The switching noise in the passband can be further reduced by pseudo-randomly switching between the sub-elements. The filter can use a delta-sigma modulator to generate a pseudo-random switching signal.

The present invention relates to a control system (12) for controlling the light output of a light emitting unit (10), which light emitting unit comprises at least one light emitting diode (LED) (14) and is adapted to emit light of at least one color, the control system comprising: a sensor unit (18) adapted to detect the light output of the light emitting unit and provide a corresponding feedback signal; and a control unit (22) adapted to control the light output of the light emitting unit based on a comparison between the feedback signal and a corresponding reference signal representing a desired light output, in order to provide an improved light output, wherein the control unit is further adapted to: determine a random switching period; determine on-time(s) for the LED(s) within the random switching period for providing the improved light output; and control energizing of the LED(s) according to the determined period and on-time(s). The present invention also relates to an LED light emitting unit arrangement, and a method for controlling the light output of an LED light emitting unit.

The invention relates to a method and a system for randomly switching alternating current. The system comprises a voltage detecting circuit, a current detecting circuit, a first switching circuit, a second switching circuit, a control circuit, a pulse width modulator (PWM) and an APFC circuit, wherein the first switching circuit is used for switching on or off a main power supply; the second switching circuit is used for switching on or off a reserve power supply; the control circuit is used for controlling the first switching circuit and the second switching circuit to switch on or off and transmitting a pulse signal to the PWM; the PWM is used for modulating an output dutyfactor according to the pulse signal transmitted by the control circuit; the APFC circuit is used for receiving the output dutyfactor of the PMW so as to control the output current, and thereby the linear rectification of the output current is realized to ensure the synchronization of the output voltage and the current phase of the APFC circuit. The state of the power supply can be automatically recognized by adopting the random switching so as to adapt to power supplies in different environments, and the switching time is greatly reduced and fixed. The current linear rectification can be randomly switched as alternating current to solve the peak interference brought by the random switching, and the power compensation is carried out to realize the minimum loss of circuit power.

The invention discloses a flexible totally-assembling system for efficient and random switching of multiple vehicle types. The flexible totally-assembling system comprises upper equipment and lower equipment. The lower equipment comprises a first station, a second station, a third station and a fourth station all of which are linearly arranged. The first station, the second station, the third station and the fourth station are each provided with a high-speed roller bed and a flexible bogie, white vehicle bodies are arranged on the flexible bogies, the flexible bogies are matched with the corresponding high-speed roller beds, the first station and the third station are completely same and are each provided with a transition rail, a rail butting device, a transition carriage and ground rails, the second station is further provided with a side body clamp, a clamp transferring vehicle, an assembly sliding table and a point positioning robot, and the fourth station is further provided with a wire welding robot, a motor tractor and a parking rail. The upper equipment comprises second-layer floors, second-layer robots and upright rods. By means of the flexible-totally-assembling system, the floor space of total assembling is reduced, the vehicle type switching time is shortened, the flexible totally-assembling system has a random switching function, and the flexible totally-assembling system meets the requirements for efficient and random switching of the multiple vehicle types of flexible total assembling.

A safety network transmitting method and its system providing a active defense technology for safe message transmitting in the network can be used in information safety field by setting up safe virtual special network to submit safety service for the data transmitting in the network. The present invention has comprehensively used the communication technology of "main-assistant" machines, the pseudo-random sequence creation technology, the rout-extension protocol and information control extension protocol, through the identification result of pseudo-random sequence message transmitted to each other between the safety routers to mark the safety of the system route and to pick up the safe pathes from the existing network as well as to submit them to the message transmitting.

The invention discloses a relay fault diagnosis circuit and a relay fault diagnosis method. The method comprises the following steps: S01: after a circuit is electrified with low voltage, controlling a detection branch selecting unit (100) by a BMS control unit (200) to perform corresponding voltage detection branch gating operation; S02: detecting the voltage at the two ends by the currently gated voltage detection branch; S03: comparing voltage detected by the voltage detection branch and judging the adhesion state of each relay according to the comparison result; and S04: if each relay in the step S03 does not adhere to each other, performing operating control on the corresponding relay, gating the corresponding voltage detection circuit to perform voltage detection, and judging the failure state of the corresponding relay according to the detected voltage. The detection branch detection unit can perform random switching among multiple to-be-detected voltage circuits, so one voltage detection unit can detect multiple paths of voltage values, the component cost of voltage detection is greatly reduced, a BMS hardware circuit is simplified, the BMS occupied space is beneficial for being reduced and the BMS performance is more stable.

The invention discloses an NPC (network parameter control) inverter mixing random SVPWM (space vector pulse width modulation) control system and method based on a Markov chain and belongs to the field of power electronic application. A three-phase sine-wave generator in the control system firstly produces a three-phase sine wave and transmits the three-phase sine wave to a SVPWM wave generator, a random number generator based on a three-state Markov chain produces a random switching frequency, a random number generator based on a two-state Markov chain produces a randomly assigned zero vector action time and transmits the vector action time to the SVPWM wave generator, and the SVPWM wave generator produces an SVPWM wave according to the received three-phase sine wave, the random switching frequency and the vector action time and transmits the SVPWM wave to a three-phase NPC topological structure. The NPC inverter mixing random SVPWM control system and method have the advantages that a harmonic wave becomes smooth at the switching frequency and integral multiples thereof, electromagnetic noise is suppressed, less electromagnetic pollution is produced, and a Markov chain random algorithm is added, so that a modulation frequency is more uniformly distributed at the periphery of an expected center frequency while advantages of a random modulation technology are guaranteed, and electromagnetic compatibility is improved.

The invention discloses a pulse width modulation implementation method for random switching frequency of a power electronic device. During the current switching period, a random number is generated by a DSP (digital signal processor) chip according to a mathematical algorithm, a periodical register value and a comparison register value are calculated by utilizing the random number; the periodical register value is stored in a shadow register of a periodical register during the current switching period to serve as a value of the periodical register in the next switching period, the comparison register value is stored in the shadow register of a comparison register during the current switching period to serve as a value of the comparison register in the next switching period; and when the current switching period is over, the random number is filled in the periodical register and the comparison register respectively by the shadow register of the periodical register and the shadow register of the comparison register. By the aid of the pulse width modulation implementation method, the length and the duty ratio of the next switching period are relatively random compared with those of the previous switching period, and the switching frequency modulated by the pulse width is randomly variable.

The invention relates to a self-protecting method for long-distance upgrading of an optical network unit. When a network administrator needs to carry out long-distance edition upgrading on an optical network unit (ONU), the self-protecting of the edition upgrading of the ONU is realized by a plurality of markers stored in non-volatile storage equipment of the ONU, wherein the markers comprise an ONU start-up subarea marker, an ONU new upgrading edition marker, an ONU edition upgrading completion marker and an ONU upgrading edition verification condition marker, and the non-volatile storage equipment of the ONU is divided into two subareas for storing ONU software edition. According to the invention, the reliability of the current operation edition and the upgrading edition of the ONU is effectively guaranteed, the phenomena of random switching of the ONU start-up edition and uncontrollability of ONU engineering application edition caused by misoperation of the network administrator when the ONU is applied to different local equipment are reduced, the ONU upgrading failure problem is repaired remotely, the engineering problem solving timeliness is improved and the robustness of the ONU equipment is enhanced.

The invention discloses a digital background correction method based on a least mean square algorithm, which is suitable for a split SAR ADC. The method comprises the following steps: firstly, settinga split SAR ADC, and performing digital background correction based on a minimum mean square algorithm on the set split SAR ADC, wherein the split type SAR ADC comprises two ADC modules, a main DAC capacitor array in each ADC module adopts a non-binary capacitor array; meanwhile, the weight of the highest-order capacitor in the main DAC redundant capacitor array is set to be minimum, so that eachcapacitor including the capacitor with the maximum weight in the main DAC capacitor array can be effectively corrected through random switching of the correction DAC capacitor array, and the linearity and the dynamic range of the ADC are improved; the introduction of the correction DAC random switching mode can effectively solve the problem that the correction is invalid due to the fact that thetwo ADC capacitors are not consistent in direction. In addition, redundancy is introduced into the main DAC capacitor array, so that dynamic errors introduced into the quantization process of the system can be weakened, the correctness of each switching is ensured, and the iteration speed is increased.

The invention relates to a sliding mode control method with random nonlinear disturbance. In order to solve the problems that random switching nonlinearity, state time delay and uncertainty cannot beprocessed simultaneously through an existing sliding mode control method, consequently, system output is greatly affected by external disturbance, and the sliding mode control precision is low, the sliding mode control method with random nonlinear disturbance comprises the steps that 1, a dynamic model of a networked control system with the random switching nonlinearity and the bounded state timedelay is established; 2, design of a sliding mode face is conducted on the dynamic model established in the step 1; 3, sliding mode dynamic of the sliding mode face is calculated; 4, the distinguish condition for ensuring the sliding mode dynamic H<infinity> is obtained, and a sliding mode face parameter matrix G is obtained by solving the distinguish condition; and a sliding mode controller is constructed according to the obtained parameter matrix G. Sliding mode control over the networked control system with the random switching nonlinearity and the bounded state time delay is achieved. Thesliding mode control method is used for the field of networked control.

The invention belongs to the field of electrical technology and discloses a phase sequence self-adaption trigger circuit of a three-phase fully-controlled rectifier induction heating power supply. The phase sequence self-adaption trigger circuit is connected in series between a three-phase alternate current and a three-phase full-bridge thyristor drive axle and mainly comprises a phase sequence judging circuit, a three-phase synchronous signal additional phase shifting and phase sequence gating circuit, a thyristor three-phase trigger pulse phase shifting circuit and a three-phase trigger phase gating and output circuit. After a three-phase switching-in phase sequence of the induction heating power supply is judged by the phase sequence judging circuit, a suitable three-phase rectifier trigger pulse is generated by the three-phase synchronous signal additional phase shifting and phase sequence gating circuit and is sent into the thyristor three-phase trigger pulse phase shifting circuit to generate phase shifting; and the three-phase rectifier trigger pulse which is subjected to phase shifting is sent to the three-phase trigger phase gating and output circuit to drive a thyristor of the three-phase full-bridge thyristor drive axle. According to the invention, the random switching-in of a line sequence of three phases of the induction heating power supply is implemented and the phase sequence self-adaption trigger circuit has the characteristics of simple structure and low cost.

The invention provides a frequency modulated continuous wave radar system based on random switching array antennas. The frequency modulated continuous wave radar system comprises a transmitting module, an antenna module, a switching module, a receiving module and a processing module, wherein the antenna module comprises the transmitting antenna and the receiving antenna, the transmitting antenna transmits transmitting signals, so that targets are scanned, and the receiving antenna receives target reflecting signals; the switching module comprises multiple gating switches and controls multiple receiving array elements to be connected with a single receiving channel, and the gating switches are switched randomly, so that the target reflecting signal of the receiving array element connected with the gating switch which is currently connected occupies the receiving channel; synthesized signals in the receiving channel and the transmitting signals are mixed through the receiving module, intermediate-frequency amplification and band-pass filtering are conducted on the mixed signals, and therefore intermediate-frequency signals are obtained; digital sampling is conducted on the intermediate-frequency signals and following processing is conducted through the processing module. Cost and complexity of the radar system can be effectively reduced by the system and the problem of space-time coupling caused by sequential switching of the switches can be effectively solved.

The invention provides a dynamic frame switching model based on SpringDM, which can deploy a plurality of data access strategies of a persistence layer on a dynamic model and provide persistence layer services for outsides in a mode of issuing SpringDM service. The dynamic model can randomly switch the plurality of data access strategies and can provide support for multi-frame OSGi (Open Scene Graphic) generalization as a general mode in which J2EE (Java 2 Enterprise Edition) persistence layer frame is deployed in the OSGi. The invention applies the dynamic model to realize the persistence layer of RFID (Radio Frequency Identification) middleware. Enterprise-level RFID middleware requires that the data persistence layer can be flexibly switched among the plurality of data access strategies so that the JDBC (Java Data Base Connectivity) of the data access strategies of the persistence layer and the data access frame Hibernate and iBatis of the persistence layer are simultaneously integrated on the OSGi frame, and the persistence layer services are provided for the RFID middleware in the mode of issuing the SpringDM service. The RFID middleware can realize that the data access strategies are randomly switched by selecting different services.