scanning frequency
1.The article analyses the traditional principle of arc coil automatic tuning, points out its limitation,sets an automatic tuning method of external signal scanning frequency arc coil, states the principle and computing formula of external signal scanning frequency and measuring,and eliminates the wearing to the contact point and the limitation of shift adjustment .
4.The results showsd that, when the number of FH frequency point is 16, FH speed rate is 2560hop/s, as the number of active multitone interfering neighboring stations is 15 or 16 , the average acquisition time with this method scanning 4 frequency points in one chip is 5.7ms and 11.2ms, resulting 50.4% and 67.4% reduction compared with the displacement waiting and searching self synchronization method, respectively.
5.This paper briefly introduces the basic principles of the phase locked loop (PLL) and pulse-controlled phase locking method, and further analyses the self catching capacity of PLL, the composition of the frequency feedback loop, the features and parameters of the frequency difference detector and so on, the results of which show that the step scanning plus the frequency guide of the frequency feedback loop can make the narrowband PLL realize the frequency catching on broadband in shorter period of time.
7.For example? we select three patterns for picture scanning lattice in general design? which are mono frequency technology pattern? dual frequency technology pattern and mutative frequency technology pattern? and analyze and discuss in depth the technology? material? cost? production? market accommodation and so on.
10.Tissue velocity imaging (TVI), developed from Doppler tissue imaging (DTI), is a new technology based on quantitative scanning, original data storage and super high frequency technique, including quantitative tissue velocity imaging (QTVI), strain rate imaging (SRI), tissue tracking imaging (TTI) and tissue synchronization imaging (TSI).
