46 results about "Phase continuity" patented technology

An x-ray diagnostic apparatus and methods performs Real-Time Digital Radiography with particular application in dental x-ray imaging modalities, such as Orthopantomography, Scannography, Linear Tomography and Cephalography, by using a versatile and modular electronic unit, featuring ultra fast computation capability to serve diversified image sensor typology and scanning modality.

In Digital Orthopantomography and Scannography, a plurality of tomographic images at different depths of the jaw can be generated, based on the pre-selection made by the user interface.

The image processing unit utilizes for the tomo-synthesis of the diagnostic image an accurate and economic digital simulator of the radiographic film speed, including a digital frequency synthesizer fed with film cassette speed digital input and high resolution clock signal, ensuring accurate and reproducible phase continuity of the output frequency signal.

It also introduces an automatic adaptation of the frame acquisition rate in frame transfer mode, based on the actual speed of the cassette unit. By this method the dynamic of the exposure signal is reduced, and a better optimization of the signal response of the x-ray detector is achieved.

A novel method and apparatus is disclosed for reducing power dissipation of RF power amplifiers when a reduced output power level is required. The mechanism has the specific purpose of optimizing the collector terminal voltage on portions of the amplifier's RF chain for maintaining linearity while minimizing power consumption. The apparatus permits a smaller DC to DC converter to be used than in prior art, such that it is implemented in the same semiconductor die or module. Furthermore, the invention eliminates the amplification and phase continuity issues that arise from switched state power amplifiers and envelope-following approaches.

The invention relates to a clarifying chamber-free continuous extracting device of a large-phase ratio easy emulsifying system and an operating method, which belong to the technical field of chemical liquid-liquid solvent extraction. The device comprises a tower body, a liquid phase disperser, a main shaft, a lifting mechanism, a motor, and the like, wherein the liquid phase disperser comprises a series of hollow concentric cylinders, and spiral type flow guide plates are arranged on the inner walls of the cylinders; and the liquid phase disperser can be used for uniformly dispersing one liquid phase in the other liquid phase by tiny particles at lower rotating speed. Because the shearing force is small when the liquid phase disperser rotates and is difficult to cause the larger turbulence of two phases of liquid flow, phenomena of unbalanced shearing force and easy emulsifying generation in the stirring process of a common stirrer are effectively avoided. The two-phase clarifying speed is high, and the phase continuity is easy for control. The spiral type flow guide plates can assist the self-absorbing type stirring and pumping process, and solves the problems of difficult full dispersion of a small-volume liquid phase and difficult large-phase ratio operation of the traditional stirring way. The device has simple structure, easy amplification and multistage series connection and realizes continuous countercurrent extracting operation.

A general purpose network tone detection method and apparatus that allows the precise and accurate recognition of North American tones (MF, DTMF (Dual-Tone Multifrequency), and CPT (Call Progress Tones)) and international MF-R2 tones as well as taking into consideration other common tones such as Calling Card Service Prompt and Recall Dial. Through the use of the Discrete Fourier Transform (DFT) on small time windows and by providing phase continuity between these windows, the results of the successive DFTs may be combined and processed by a second DFT computation. This second DFT allows higher frequency resolution without requiring the re-computation of the DFT from the time samples. The resulting effect is a tone receiver with both high time and frequency resolution which consequently leads to robust and accurate tone recognition systems conforming even to the most stringent specification while maintaining low computational requirements.

The invention discloses a phase prediction method and system for improving GNSS receiver carrier wave phase continuity. The method comprises the following steps of S100, according to the relation between the carrier wave phase of a GNSS receiver and Doppler, constructing a carrier wave phase prediction model; S200, according to the positions and speed information of a satellite and the GNSS receiver, resolving the motion Doppler value of the satellite of a normal tracking channel relative to the GNSS receiver; S300, resolving the Doppler prediction value of an open loop tracking channel; and S400, using the carrier wave phase prediction model to carry out integral on the Doppler prediction value of the open loop tracking channel, and acquiring the carrier wave phase estimation value of theopen loop tracking channel. In the invention, the carrier wave phase discontinuity problem of the GNSS receiver under the condition of partial satellite short-time shielding can be solved so that purposes of improving the carrier wave phase continuity of the GNSS receiver and increasing positioning precision are reached.

A phase discontinuity mitigation implementation within a phased lock loop (PLL) improves throughput of a radio access technology. The throughput is improved by maintaining a phase of the PLL while powering off some devices of the PLL, such as a local oscillator (LO) frequency divider. In one instance, when the PLL is powered down, one or more portions of a delta sigma modulator for the PLL are clocked with a reference clock for the PLL. This implementation maintains phase continuity when the first phase lock loop turns back on.

The invention discloses an asymmetric triangle frequency modulation radar communication integrated signal waveform determination method. An integrated signal waveform is an asymmetric triangle and is composed of two segments of liner frequency modulation signals with opposite frequency modulation rate symbols. First of all, a bandwidth B and a time width T of an integrated system are determined; the system time width T is divided into two segments, and time lengths are respectively T1 and T2; the tuning rate symbols of the two segments of the linear frequency modulation signals are opposite, the bandwidth B is the same, and tuning rates of the two segments of the linear frequency modulation signals are respectively calculated; the first segment of signals are used for synchronous capture of communication signals, and communication information is not modulated; for the second segment of signals, communication bit information is modulated segment by segment; and phase continuity of the two segments of signals is ensured, and an expression of integrated signals on the whole time width T is finally obtained. According to the invention, waveform integration of a radar and the communication signals can be realized, a part of integrated signals are taken as a synchronization sequence for synchronization of a communication system, the communication bit information is modulated segment by segment for the residual part of the integrated signals, and the whole integrated signals are taken as radar emission signals.

The invention relates to a DDS (Direct Digital Frequency Synthesizer) frequency hopping device used for the laser time sequence control of a cold atom interferometer. The device comprises an upper computer with a LABVIEW control program, an ARM (Advanced RISC Machines) chip, a CPLD (Complex Programmable Logic Device) chip, a rubydium atomic clock, a radio frequency chip and a DDS chip. The setting of frequencies required for the atomic velocity selection and the microwave frequency mixing of the cold atom interferometer as well as for an atomic wave packet to carry out beam splitting, inversion and beam combination under a function of a [Pi]/2-[Pi]-[Pi]/2 Raman pulse sequence can be realized. The device adopts the following methods that the rubidium atomic clock is used for replacing a common quartz crystal oscillator, and the reference crystal oscillator of the complex programmable logic device chip and the reference crystal oscillator of the DDS chip use the same radio frequency source. Compared with a traditional DDS frequency hopping device, the device disclosed by the invention is characterized in that the setting of the frequencies of different hopping frequencies and frequency time intervals can be realized, and the device exhibits a higher phase noise level and higher phase continuity on an aspect of output frequency switching.

A digitally controlled frequency synthesizer has a first direct digital synthesizer that generates a first phase-coherent, time-varying frequency, and a second direct digital synthesizer that generates an offset frequency waveform. A plurality of cascaded frequency converters successively combine the offset frequency waveform with a reference frequency waveform to produce a plurality of waveforms having respectively different frequencies. A switch switches between the plurality of waveforms produced by the cascaded frequency converters to realize a second waveform. The operation of the second direct digital synthesizer is controlled so as to maintain phase continuity between respective ones of the plurality of waveforms contained in the second waveform as output by the switch. A mixer multiplies the first waveform by the second waveform to produce a time-varying output frequency.

The invention discloses a method for ensuring channel phase continuity among resource block (RB) groups after precoding, and a base station. The method comprises: the base station carrying out channel estimation through sounding reference signals (SRSs), and obtaining an uplink channel, and based on reciprocity between the uplink channel and a downlink channel, obtaining the corresponding downlink channel; the base station, based on the obtained downlink channel, calculating a weight phase correction factor, and correcting a precoding weight by use of the weight phase correction factor; and the base station, according to the corrected precoding weight, carrying out data precoding and transmission. According to the invention, the channel phase continuity among the RB groups after the precoding can be ensured, and the system performance and the frequency spectrum efficiency are improved.

The invention discloses a short time burst communication carrier synchronization method based on signal forward-reverse order cyclic splicing. According to the method, the carrier synchronization purpose is mainly achieved by storing a received short time burst signal, circularly using signals entering a digital receiver in the forms of forward order and reverse order based on the idea of backtracking to ensure the phase continuity, and continuously performing phase-locked loop processing. By adoption of the signal forward-reverse order cyclic splicing method, the carrier synchronization can still be completed under the condition that the received data length is very short, and the problem of phase mutation when the received data are processed is well solved.

The invention relates to a modulation method and a modulation device by which optical continuous phase frequency shift keying (CPFSK) with any modulation index can be realized. The device comprises a modulation part and a demodulation part, wherein the modulation part is implemented by using a two-arm structure of a mach zehnder interferometer (MZM), and a phase continuity mode is implemented by controlling the time delay of an input waveform. The invention can provide a modulation-index variable optical CPFSK method and a modulation-index variable optical CPFSK device, by which an optical CPFSK signal with constant envelope, continuous phases and any modulation index can be generated, thereby overcoming a nonlinear effect in an optical transmission process, and improving the dispersion tolerance and the PMD (polarization mode dispersion) tolerance.

The invention relates to a digital Moire fringe phase extraction method based on nonlinear optimization, belonging to the technical field of optical measurement and image processing. According to the method, a Moire synthesis light intensity distribution graph mathematical model is established, a fringe phase is used as an optimization variable, with actual Moire synthesis graph light intensity distribution as an optimization target, phase continuity is taken as a boundary condition, through nonlinear optimization calculation, the light intensity distribution of the mathematical model is equal to the light intensity distribution of an actual Moire synthesis graph, and the fringe phase at that time is the Moire fringe phase of the actual Moire synthesis graph. According to the method, the Moire fringe phase can be obtained without low pass filtering, a filtering error in a spectrum aliasing condition can be avoided, and a phase measurement precision is improved.

The invention relates to a method for monitoring the earth surface deformation based on a sequential InSAR technology. The method comprises steps of SAR data selection, stereo image pair registration,noise filtering processing, interference fringe pattern generation, de-leveling effect execution, phase unwrapping, elevation and elevation coordinate system conversion. The method is especially suitable for high-precision phase unwrapping in areas with large topographic relief, such as a mountainous area and frequent surface deformation, such as an artificial active area; defects caused by inapplicability to the phase continuity assumption and the surface elevation invariance assumption in the conventional algorithm can be overcome; the phase unwrapping accuracy can be improved and thus thesurface elevation deformation inversion accuracy can be enhanced; and a high-precision monitoring way is provided for geological disasters along the transmission line in the region.

The invention provides a four-phase seepage simulation method for a movable gel system. The method includes the steps of dividing the movable gel system into a movable gel and a gel particle, establishing a movable gel system four-phase seepage model containing the gel particle, and based on the model, establishing a four-phase seepage mathematical model taking an oil phase, a gas phase, a water phase and the gel particle into account and containing a four-phase continuity equation, initial conditions, boundary conditions and a characteristic equation. According to the method, the gel particle serves as an independent phase different from the oil phase, the gas phase and the water phase, main physical and chemical mechanisms for profile control and oil displacement of the movable gel system are comprehensively described, and simulated prediction results are high in availability, targeting property and accuracy, so that the four-phase seepage simulation method for profile control and oil displacement of the movable gel system in accordance with geological characteristics and development characteristics of Chinese oil fields can be achieved.

Certain aspects of the present disclosure propose methods for improving phase continuity in an uplink transmit time interval (TTI) bundle. A first method may include identifying a segment of UL subframes in the TTI bundle and maintaining substantially the same transmit power/timing/frequency when transmitting data to a node over the segment of UL subframes in the TTI bundle. Another method may include ignoring reception of downlink subframes for a duration of the TTI bundle.

The invention discloses a radio frequency watermark embedding and extracting method for CPM signal, and belongs to the field of radio frequency watermarks; the method comprises the steps of using a CPM baseband signal as a carrier signal, superimposing a watermark signal on the phase of the carrier signal according to the watermark embedding ratio so as to obtain a baseband signal, and modulatingthe baseband signal to a carrier frequency to form a CPM radio frequency signal; reducing the carrier frequency of the CPM radio frequency signal to a zero intermediate frequency, so as to obtain a baseband signal; demodulating the baseband signal, reconstructing the carrier signal phase after the carrier code element is obtained, carrying out phase unfolding on the baseband signal to obtain a signal phase, removing the reconstructed carrier signal phase from the signal phase, and obtaining a watermark signal; carrying out polar detection on the watermark signal, and demodulating the bit information contained in the watermark signal. According to the method in the invention, when the watermark bit is switched, the phase continuity of the signal is not damaged; and the system performance isguaranteed to be unchanged.

A scale is configured to measure a displacement or velocity of a rotating object. The scale includes a first region that includes a first mark row including a plurality of marks arranged in a first period, and a second region that includes a second mark row including a plurality of marks arranged in a second period having a phase continuity with the first mark row formed in the first region. A periodic mark row including the first mark row and the second mark row is formed over an entire circumference of the rotating object including the first region and the second region.