To determine the feasibility and practicability of interrupt continuous wave (CW) approach proposed for real time simulating radar intermediate frequency(IF) video signal, theoretical analysis and computer simulation...To determine the feasibility and practicability of interrupt continuous wave (CW) approach proposed for real time simulating radar intermediate frequency(IF) video signal, theoretical analysis and computer simulation were used. Phases at two linked points between the end and beginning of adjoined frames are always consistent; the bias Doppler frequency for the time delay of A/D sampling start responds to that for target acceleration. No digital phase compensation is required at continuous points, and the interrupt CW approach has apparently practical values.展开更多
By jitter performance comparison between PLL (Phase Locked Loop) and DLL (Delay Locked Loop),a helpful equation is derived for the structure choice between DLL and PLL based synthesizers fabricated in CMOS processes ...By jitter performance comparison between PLL (Phase Locked Loop) and DLL (Delay Locked Loop),a helpful equation is derived for the structure choice between DLL and PLL based synthesizers fabricated in CMOS processes to get an optimum jitter performance and power consumption.For a frequency synthesizer,a large multiple factor prefers PLL based configuration which consumes less power,while a small one needs DLL based topology which produces a better jitter performance.展开更多
A simple method used for simultaneous measurement of phase retardation and optic axis of wave plate by employing 1/4 wave plate is demonstrated. The theoretical analysis of the measuring principle is presented in deta...A simple method used for simultaneous measurement of phase retardation and optic axis of wave plate by employing 1/4 wave plate is demonstrated. The theoretical analysis of the measuring principle is presented in detail. In the measurement, after adjusting a standard 1/4 wave plate and the fast (slow) axis of the plate to be measured parallel to the pass axis of the polarizer, the plate to be measured is rotated by 450 counterclockwisly. A stepping motor is used to rotate the analyzer. The experimental data are collected by a photodetector and then sent to a computer. According to the output data curve, the phase retardation and optic axis of the plate to be measured can be obtained simultaneously. To test the feasibility of the method, a λ /2 and a λ /8 wave plates are used as examples to demonstrate the measurement procedures. The phase retardation measurement accuracy is better than 0.5×10-2. This method can be used to measure the arbitrary phase retardation conveniently.展开更多
In this paper, we study how adaptive coupling with time-periodic growth speed (TPGS) affects the spiking synchronization of weighted adaptive Newman-Watts Hodgkin-Huxley neuron networks with time delays. It is found t...In this paper, we study how adaptive coupling with time-periodic growth speed (TPGS) affects the spiking synchronization of weighted adaptive Newman-Watts Hodgkin-Huxley neuron networks with time delays. It is found that the neuronal spiking intermittently exhibits synchronization transitions between desynchronization and in-phase synchronization or anti-phase synchronization as TPGS amplitude or frequency is varied, showing multiple synchronization transitions. These transitions depend on the values of time delay and can occur only when time delay is close to those values that can induce synchronization transitions when the growth speed is fixed. These results show that the adaptive coupling with TPGS has great influence on the spiking synchronization of the neuronal networks and thus plays a crucial role in the information processing and transmission in neural systems.展开更多
文摘To determine the feasibility and practicability of interrupt continuous wave (CW) approach proposed for real time simulating radar intermediate frequency(IF) video signal, theoretical analysis and computer simulation were used. Phases at two linked points between the end and beginning of adjoined frames are always consistent; the bias Doppler frequency for the time delay of A/D sampling start responds to that for target acceleration. No digital phase compensation is required at continuous points, and the interrupt CW approach has apparently practical values.
文摘By jitter performance comparison between PLL (Phase Locked Loop) and DLL (Delay Locked Loop),a helpful equation is derived for the structure choice between DLL and PLL based synthesizers fabricated in CMOS processes to get an optimum jitter performance and power consumption.For a frequency synthesizer,a large multiple factor prefers PLL based configuration which consumes less power,while a small one needs DLL based topology which produces a better jitter performance.
文摘A simple method used for simultaneous measurement of phase retardation and optic axis of wave plate by employing 1/4 wave plate is demonstrated. The theoretical analysis of the measuring principle is presented in detail. In the measurement, after adjusting a standard 1/4 wave plate and the fast (slow) axis of the plate to be measured parallel to the pass axis of the polarizer, the plate to be measured is rotated by 450 counterclockwisly. A stepping motor is used to rotate the analyzer. The experimental data are collected by a photodetector and then sent to a computer. According to the output data curve, the phase retardation and optic axis of the plate to be measured can be obtained simultaneously. To test the feasibility of the method, a λ /2 and a λ /8 wave plates are used as examples to demonstrate the measurement procedures. The phase retardation measurement accuracy is better than 0.5×10-2. This method can be used to measure the arbitrary phase retardation conveniently.
基金financially supported by the Natural Science Foundation of Shandong Province of China (ZR2012AM013)
文摘In this paper, we study how adaptive coupling with time-periodic growth speed (TPGS) affects the spiking synchronization of weighted adaptive Newman-Watts Hodgkin-Huxley neuron networks with time delays. It is found that the neuronal spiking intermittently exhibits synchronization transitions between desynchronization and in-phase synchronization or anti-phase synchronization as TPGS amplitude or frequency is varied, showing multiple synchronization transitions. These transitions depend on the values of time delay and can occur only when time delay is close to those values that can induce synchronization transitions when the growth speed is fixed. These results show that the adaptive coupling with TPGS has great influence on the spiking synchronization of the neuronal networks and thus plays a crucial role in the information processing and transmission in neural systems.
