542results about How to "Reduce peak" patented technology

A noise suppression device receives data representative of a noise-corrupted signal which contains a speech signal and a noise signal, divides the received data into data frames, and then passes the data frames through a pre-filter to remove a dc-component and the minimum phase aspect of the noise-corrupted signal. The noise suppression device appends adjacent data frames to eliminate boundary discontinuities, and applies fast Fourier transform to the appended data frames. A voice activity detector of the noise suppression device determines if the noise-corrupted signal contains the speech signal based on components in the time domain and the frequency domain. A smoothed Wiener filter of the noise suppression device filters the data frames in the frequency domain using different sizes of a window based on the existence of the speech signal. Filter coefficients used for Wiener filter are smoothed before filtering. The noise suppression device modifies magnitude of the time domain data based on the voicing information outputted from the voice activity detector.

A large-scale content delivery system may be achieved, which may send a large amount of contents without intensive management of the contents in the server. In a service providing system where a client, a service gateway, and a server are connected to each other through a network, the client sends a first message to the server by way of the service gateway. The service gateway inquires a processing method of the first message from the client of the server by using a second message that includes a part of the first message content. The server replies to the inquiry of the processing method from the service gateway with a program that describes the processing method, and the service gateway processes the first message from the client on the basis of the received processing method.

A socket is attached to an end of one pipe and a plug is attached to an end of another pipe. The socket is provided with a pair of notched grooves at peripheral faces on both sides opposed to each other and a stopper constituting a U-shape is mounted onto the notched groove. The plug is provided with a first taper portion, a flat portion, and a second taper portion continuously from a front end side thereof in a sectional shape thereof along an axial direction, and a groove having the stopper inserted therein is formed at a ridge portion of the second taper portion. An inner periphery of the socket is arranged with a seal ring for sealing an interval between the inner periphery of the socket and an outer periphery of the plug in an airtight connection.

Provided is a method of reducing a peak-to-average-power ratio in a multiple antenna orthogonal frequency division multiplexing communication system. The method includes: reducing a peak-to-average-power ratio of input serial data sequences; space-time coding the input serial data sequences with the reduced peak-to-average-power ratio to generate N symbols to be tranmitted via N antennas; receiving the serial data sequences of the N symbols to transform the serial data sequences into N parallel data sequences; allocating each of the N parallel data sequences to Ns sub-carriers and performing Inverse Fast Fourier Transform on the N parallel data sequences; transforming the N parallel data sequences into N serial data symbols; and replicating a portion of the serial data symbols to generate cyclic prefixes and interleaving the cyclic prefixes into starting portions of the serial data symbols to cyclically expand the N symbols.

The invention relates to a multi-operating mode energy-saving controlled combined type thermostatic and humidistatic air conditioning unit with a thermometal compound box body structure special for nuclear power stations. The air conditioning unit comprises a control system and a box body structure, wherein a primary-efficiency filter, a medium-efficiency filter, a surface cooler, a heater, a humidifier and a blow-off device are sequentially arranged in the box body; the front side of the primary-efficiency filter is provided with a fresh air and return air mixing section, and inlets of fresh air and return air are respectively provided with a fresh air proportioning valve and a return air proportioning valve; the control system adopts a programmable logic controller (PLC) and adopts air conditioning multi-operating mode zone control to realize the energy-saving operation of the unit; the surface cooler adopts a large temperature difference cold water heat exchanging technology and can save the investment and operation expenses of a water system; and the box body adopts a double-layer compound structure and an anti-shock device to meet the special requirements on the nuclear power stations. The invention has the characteristics of high efficiency, energy saving, good tightness, strong anti-shock capacity, safety, reliability, long service life, and the like.

The invention relates to the field of microwave power device technology in semiconductor material and discloses a method for fabricating an AlGaN/GaN high-electron mobility transistor (AlGaN/GaN HEMT) multilayer field plate device. The method comprises, based on common AlGaN/GaN HEMT device fabrication process, firstly fabricating a gate connection field plate after forming a gate metal contact, secondly fabricating a source connection field plate, and forming the AlGaN/GaN HEMT multilayer field plate device. The invention simultaneously discloses an AlGaN/GaN HEMT multilayer field plate device. The invention can greatly improve the breakdown characteristics of the AlGaN/GaN HEMT device and effectively suppress the current collapse of the AlGaN/GaN HEMT device.

The invention discloses a frame synchronization method applicable to a burst communication system. A multi-path segmented coherence relevance mode with different segmentation lengths is adopted in an initial signal channel access stage, the maximum relevance value of each branch path is adopted for carrying out double-threshold value (relative threshold value and absolute value) judgment, the synchronous confirmation is carried out from the position with the relevance value exceeding the threshold value, and the influence of severe environment factors in the initial signal channel access stage is overcome through the setting of proper double threshold values and conforming windows; and a full coherence relevance mode is adopted in a stable communication stage, the prior double threshold values and conforming window width are set according to the signal channel information recorded in the conforming windows in the initial signal channel access stage, and the method and the device have higher adaptability through different frame synchronization methods adopted in different communication stages.

A supply-regulated VCO exhibits reduced or no supply sensitivity peaking. The VCO includes an oscillator whose supply current is regulated to control the oscillating frequency of the oscillator. A VCO input signal controls the supply current so that there is a relationship between the input signal and the oscillator output frequency. Power supply noise that might otherwise affect oscillator operation is shunted from a supply current input lead of the oscillator to ground by a bypass capacitor. In one example, an auxiliary circuit supplies an auxiliary supply current to the oscillator, thereby reducing the amount of supply current a supply regulation control loop circuit must supply. In another example, a supply regulation control loop circuit supplies a control current to a main oscillator, but the bypass capacitor is not coupled to this oscillator but rather is coupled to a slave oscillator that is injection locked to the main oscillator.

A method for crest factor reduction of a multi-carrier signal is disclosed. The multi-carrier signal comprises a plurality of single-carrier signals, each single-carrier signal having signal-specific spectral properties. The method comprises identifying a peak in the multi-carrier signal and a time of occurrence of the peak and generating a plurality of cancellation pulses depending on the time of occurrence of the peak. A particular cancellation pulse of the plurality of cancellation pulses is associated with a particular single-carrier signal and cancellation pulse-specific spectral properties of the particular cancellation pulse substantially match the signal-specific spectral properties of the associated particular single-carrier signal. The method further comprises combining the plurality of cancellation pulses to form a combined cancellation pulse and applying the combined cancellation pulse to the multi-carrier signal to reduce the peak. A corresponding circuit and corresponding computer program products useable during manufacture and operation are also disclosed.

The invention discloses a full-firing-direction autonomous reentry guidance method based on a three-dimensional reentry trajectory analytical solution. The full-firing-direction autonomous reentry guidance method comprises the following steps of 1, building of a kinematical equation and a dynamical equation, 2, summarizing of the reentry guidance method, 3, descent stage guidance strategies, 4, steady gliding stage guidance strategies and 5 height-adjustment stage guidance strategies. The full-firing-direction autonomous reentry guidance method has the advantages that reentry guidance of an aircraft with the large lift-drag ratio can be guided effectively, low-damping and long-period trajectory oscillation caused by the high lift-drag ratio can be restrained effectively, the peak value ofthe heat flux density is reduced, and tracking of a reference track is facilitated; inertia force caused by earth rotation and actual aerodynamic force are combined into equivalent aerodynamic force,an equivalent aerodynamic section is planned through the analytical solution, and thus the aircraft has the omni-directional reentry task processing capability; and an equivalent aerodynamic section fitting formula based on the inverse proportional function is put forward, the reentry trajectory analytical solution based on the complex equivalent aerodynamic section form is further deduced, and thus high precision, all-dimensional applicability and high robustness are achieved.

A technique of mapping data, suitable for Peak to Average Power Ratio (PAPR) reduction while transmitting data portions via a communication channel limited by a peak power p_peak. The mapping is performed by utilizing a Markovian symbol transition probability distribution with quantized probabilities and by selecting, for a specific data portion at a current channel state, such a binary symbol (called thinned label) which allows puncturing one or more bits in the thinned label's bit sequence before transmission.

A gradient sensitivity based method is described for reducing Peak to Average Power Ratio in multicarrier communication systems. The method involves definition of a differentiable penalty function which has non-zero values whenever there is a peak violation. The gradient of the function with respect to the symbol magnitudes and phases is evaluated at the given symbol vector. Symbol perturbations are computed in the opposite direction of the gradient in such a way that the peaks are reduced and the amount of errors introduced in the symbols is not large enough to affect the decoding process. In order to reduce computation, a variant of the method is proposed where a peak reduction kernel is precomputed and stored. The kernel is rotated to the location of the peak and added with proper sign to reduce PAR.

A transmitter is provided which effectively reduces a peak that occurs in transmitting signal electric power. A baseband limiter means 11 applies a peak reduction process to digital signals to be a transmission target on a plurality of carriers in a baseband. Band limiting filter means A1 to An apply a band limitation process to the digital signals on each of the carriers to which the peak reduction process is applied. Quadrature modulation processing means C1 to Cn apply a quadrature modulation process to the digital signals on each of the carriers to which the band limitation process is applied. An adding means 12 adds the digital signals on each of the carriers to which the quadrature modulation process is applied. An intermediate frequency limiter means 2 multiplies a signal of the added result by a window function that is weighted depending on the magnitude of the detected peak, and applies a peak reduction process thereto. At this time, when a plurality of peak reduction processes is overlapped with each other, a weight of the subsequent window function is made small to prevent excessive suppression.

An inventive system and method for group communication among devices in M2M networks comprises associating one or more of the devices with a gateway having a unique identifier, initiating registration of the devices at an M2M network using the unique identifier of the gateway, providing from the network a temporary identifier to the gateway and associating, in the network, the temporary identifier with the gateway, attaching the devices to the network using the temporary identifier, and communicating information between the network and the device through the gateway. In one aspect, the devices can be classified into sub-groups and each sub-group has a sub-group head that can be attached to the gateway so that the devices can communicate with the network through the sub-group head instead of the gateway. Each sub-group can be associated with a unique temporary identifier, in addition to the temporary identifier associated with the gateway.

A pulse detonation combustor includes at least one plenum located along the length of the pulse detonation combustor. The plenum can be located: 1) proximate an air valve; 2) between a fuel injection port and an ignition source; 3) downstream of both the fuel injection port and the ignition source; and 4) proximate an exit nozzle of the pulse detonation combustor. In addition, the pulse detonation combustor can have multiple plenums, for example, proximate the air valve and proximate the exit nozzle. The location and dimensions of the plenum can be selectively adjusted to control mechanical loading on the wall, the velocity of fluid flowing within the combustor, and the pressure generated by the pulse detonation combustor.

The invention discloses a vehicle-mounted composite power supply system of an electric vehicle and a control method. Through a voltage and current acquisition circuit, a voltage value and a current value of a motor inverter end, and voltage values of a battery set and a supercapacitor are obtained, and the processed to obtain required power, battery set SOC and supercapacitor SOC, which are used as decision-making input variables of a fuzzy logic control module. According to actual operation working conditions of the electric vehicle, a proper logic threshold value control strategy is formulated and by use of fuzzy control, fuzzification is performed on fixed rule parameters in a logic threshold, so rules are further refined, control thinking is further precise and results are further optimized. Compared with real-time power, the peak value of actual average power and the switching frequency are greatly reduced. By combining the power hysteresis control, the switching frequency of working modes of the system and the output frequency of the battery set are further improved, energy loss, caused by mode switching, of a vehicle-mounted double-energy system is reduced, service lifetime of the battery set is prolonged and efficiency and stability of the system are improved.

Communication systems employing subchannel communication such as OFDM or multicode CDMA have a disadvantage of power variation of the transmitted signal. The present invention provides reduced power variation without compromising performance or bandwidth. Information symbols to be transmitted on the individual subchannel are fed to encoders which map the information symbols into channel symbols by increasing their order. The encoding in response to a forward error correction scheme and includes selection between redundant symbol values to reduce power variation. Preferably the encoder includes a trellis coder jointly encoding the symbols and a compensation data set to reduce power variation.

An amplification system and method is provided that reduces peaks associated with an input signal, and provides correction, in one or more spectral bands, to signal distortion and out-of-band emissions that result from the peak reduction. The correction signal that removes signal distortion and OOB emissions associated with the peak reduction can be calculated or electronically derived. The correction signal can be combined with the peak reduced signal prior to or after amplification of the peak reduced input signal.

An apparatus and method for power control in a cellular basestation transmitter with multiple digital carrier channels. Each digital carrier signal is attenuated by a digital power control circuit under the control of a microcontroller, the amount of attenuation varying according to the number of active channels. The attenuated digital signals are combined and converted to an analog signal by a digital to analog converter, and the analog signal is amplified by an analog power control circuit also under control of the microcontroller. The combined digital signal may be clipped to reduce the signal peaks, the amount of clipping varying according to the number of active channels.

The invention provides a 100% low floor tramcar non-power bogie and a tramcar. The 100% low floor tramcar non-power bogie comprises a bogie framework; one anti-twisting device for regulating relative positions of the bogie framework and a vehicle body is arranged at the front end and the rear end of the bogie framework respectively. According to the 100% low floor tramcar non-power bogie and the tramcar which are provided by the invention, through the arrangement of the anti-twisting devices at the two ends of the bogie framework, the bogie has good guidance quality in the running process of the tramcar, the peak of force applied by each wheel to a rail can be greatly reduced, wear of a rim of each wheel on a curve track, which is caused by the case that the wheel is close to the steel rail, is reduced, the service life of the tramcar is prolonged, and meanwhile the tramcar has an automatic resetting and centring function, so that the tramcar has good comfort.