43results about How to "Guaranteed dynamic range" patented technology

A digital broadcasting apparatus in which the phase of the carrier of the signal of a digital terrestrial broadcasting is controlled depending on the frequency of its transmission channel so as to suppress an increase of the dynamic range of the signal. A frequency interleaving circuit interleaves the frequency of the main signal generated according to audio data with a parameter determined according to the frequency of the transmission channel, and a sub-signal generating circuit generates a sub-signal including a pilot signal for transmission control. A mapping circuit modulates the sub-signal by using a pseudo-random number sequence produced according to the initial value of the random number code preset according to the frequency of the transmission channel. The frequency-interleaved main signal and the modulated sub-signal are subjected to OFDM modulation. After the frequency is converted to the frequency of the transmission channel, the signal is radiated from an antenna, thus suppressing an increase of the dynamic range of the broadcasting signal.

A plurality of conversion characteristic functions 90, 92, and 94 used in a gamma correction circuit are stored in the processor in advance. A characteristic setting circuit sets standard characteristics 90 to the gamma correction circuit when exposure time E and a gain G are small. When E is large and G is small, change to correction characteristics 92 is made where inclination is set small at a low signal level, and amplification in a noise level at the low signal level is suppressed. When G is large, change to correction characteristics 94 having gentle inclination over a wider range than the characteristics 92 is made, and the amplification of the noise level that becomes larger in proportion to the G by gradation correction in the gamma correction circuit is suppressed.

In the present invention, it is possible to precisely adjust the intensity of light emitted from a light source and ensure a dynamic range from high brightness to low brightness even in a field-sequential color drive format for turning light on and off at high speed. A light intensity detection signal (SFB) indicative of the intensity of light emitted by a light source (11) is acquired, and on the basis of the light intensity detection signal (SFB) and a set reference signal (SA), a comparison circuit (410) generates a comparison signal (SB) indicative of turning ON and OFF. Within a sub-frame period, a logic circuit (420) repeats turning ON / OFF based on a pulse signal inputted from the comparison circuit (410), and outputs a lighting signal (SD1) for causing the light source (11) to emit light in accordance with the reference signal (SA) which is a set value, and outputs a non-lighting signal (SD2) for causing the light source (11) to not emit light in accordance with a set value.

The invention discloses a signal drift dynamic correction method and device. A direct-current recovery ring circuit is adopted for achieving dynamic correction of signal drift of photoelectric detector pre-circuit output, a signal amplification and conditioning circuit and the like, in the period of detecting a dark object, a switch S1 is closed, direct-current recovery is executed on a feedback loop, output is forced to reach a set low value, the switch S1 is disconnected to make direct-current recover a datum point A point level clamp, and a B point level is collected to serve as current background data; by switching to a scene target, an input scene target signal is overlaid on a direct-current level of the A point clamp, a B point level is collected to serve as the sum of scene targetdata and the background data, and scene target data can be obtained by subtracting the background data. The above-mentioned operations are repeated periodically, and the scene target data can be continuously obtained. Accordingly, the background signal level can be inhibited, the signal dynamic range can be widened, the system measurement precision is effectively improved, and the method and device are specially suitable for the technical field of space remote sensing.

A digital high speed automatic gain preconditioning device comprises a coupler, a wave detector, an analog-to-digital converter, a digital-to-analog converter, a variable gain amplifier, a high-accuracy analog-to-digital converter, an FPGA regular processor and a digital signal processor. The device uses a feedforward structure; the coupler outputs two paths of signals, wherein one path enters the variable gain amplifier, and the other path enters the wave detector; the output of the wave detector obtains an intermediate frequency signal power value after the sampling of the analog-to-digital converter; the control quantity of the variable gain amplifier is obtained after the intermediate frequency signal power value is input to the FPGA regular processor and processed according to certain rules; and the control quantity controls the yield value of the variable gain amplifier after the conversion of the digital-to-analog converter. In the device, under the condition of guaranteeing dynamic range, stability and accuracy, quantitative reduction automatically gain and adjust the required time, thereby improving the scanning speed of an electromagnetic signal analyzer; and the control logic is finished by the FPGA regular processor without occupying the resources of the digital signal processor.

Transition to the logarithmic range does not require the entire bit range of the result that is linearly dependent on the square of the value. Rather, for a value having x bits, the result can be scaled in such a manner that a representation with less than x bits of the result is sufficient to obtain the logarithmic representation based thereon. The effect of the scaling factor on the resulting logarithmic representation can be cancelled by adding a correction value obtained by using the logarithmic function on the scaling factor to or subtracting it from the scaled logarithmic function without dynamic loss. The invention provides a method and a device for producing a representation of a calculation result that is linearly dependent on the square of a value, thereby allowing to carry out the calculation easily or with little hardware.

A low-power ultra-wideband low-noise amplifier, the low-noise amplifier adopts a symmetrical structure, including: an enhanced pseudo-high electron mobility transistor as a first-stage amplifier, a current feedback amplifier as a second-stage amplifier, and a balun , where the input signal is amplified by the enhanced pseudo-high electron mobility transistor, the signal is coupled to the current feedback amplifier through AC, the output terminals of the two current feedback amplifiers are respectively connected to the balun, and the balun combines the differential signals is a terminal output, wherein the enhanced pseudo high electron mobility transistor is biased through an operational amplifier. The present invention reduces the impact of the noise of the post-stage amplifier on the noise performance of the entire LNA, greatly reduces the drain current by reducing the gate voltage and increasing the resistance of the drain, and at the same time ensures the dynamic range of the amplifier and the noise of the entire LNA It has been significantly improved, and the power consumption is less than a quarter of LOFAR's LNA.

The invention discloses a real-time block floating point frequency domain four-route pulse compressor and a pulse compression method thereof, and the problems that the existing pulse compression technology is long in time delay and poor in reusability are solved. The pulse compressor comprises an input data conversion module (1), a block floating point FFT module (2), a four-route matching multiplying module (3), a block floating point IFFT module (4) and an output data conversion module (5). A route of input serial data are converted by the first module (1) to four-route parallel block floating point data which are supplied to the second module (2) for FFT, after FFT, the data are supplied to the third module (3) for four-route matching multiplication, multiplication results are subjected to IFFT by the fourth module (4), and after IFFT, the data are converted by the fifth module (5) to be a route of serial fixed-point data or a route of serial floating-point data which are used as output results of pulse compression. The real-time block floating point frequency domain four-route pulse compressor has the advantages of being short in time delay and high in real-time ability, and can be used for real-time processing of radar signals.

The present application proposes an imaging control method, device, electronic device, and readable storage medium. The imaging device includes a pixel unit array composed of a plurality of light-sensitive pixel units. The method includes: when the shooting scene belongs to a dark environment whose brightness is less than a threshold brightness , according to the exposure ratio of the long-exposure pixel and the short-exposure pixel in the shooting scene, determine whether the shooting scene belongs to the high dynamic range whose exposure ratio is greater than the first exposure ratio threshold, if the shooting scene belongs to the high dynamic range, the control pixel unit array adopts at least two Execute the step of outputting the original pixel information of each exposure pixel multiple times for various exposure durations, so as to generate a corresponding first image according to the original pixel information output each time, wherein the step of outputting the original pixel information of each exposure pixel is performed each time In the first step, the same exposure time is used for the pixel unit array, and the composite processing is finally performed according to the first images of each frame. As a result, the imaging effect and imaging quality are improved, and the user's shooting experience is improved.