A short time signal generating method based on time comb principle

The status of phase differences in the least common multiple period between two signals with various frequencies has obvious regularity. As phase differences are arrayed in accordance with the order from small to large, differences of adjacent phase differences are fixed to the quantified phase shift resolution (QPSR) which can be calculated by frequencies of two signals. When frequencies of two signals are f
_A
= Af
_maxc
and f
_B
= Bf
_maxc
, respectively, where two positive integers A and B are prime with each other and f
_maxc
is the greatest common factor frequency between f
_A
and f
_B
. QPSR of them is determined by f
_maxc
/ (f
_A
ldr f
_B
). In the specific frequency relation, phase differences of two signals increase or decrease gradually with QPSR as stepping value. These phase differences with regular time widths form a time comb which's total time length is a least common multiple period of two signals. In this time comb there are various pulses which have different pulse widths from zero to a period of the lower frequency signal. Therefore time comb can be used to generate pulse signals with various time widths. QPSR is the inherent characteristics of two frequency signals and it is very accuracy and small. For example, QPSR of 1 MHz and 1.0001 MHz signals is 0.1 ns. So a time comb formed by the signals with specific frequency relation combining with pulse selection circuit can generate different high-accuracy short time pulse signals. Based on this method, not only the non-periodic short time signal can be generated, but also the periodic short time signal and the period depends on the least common multiple period of these two signal.