CN104316775A - Pulse signal cycle and duty ratio continuous measurement method - Google Patents

Pulse signal cycle and duty ratio continuous measurement method Download PDF

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CN104316775A
CN104316775A CN201410591468.2A CN201410591468A CN104316775A CN 104316775 A CN104316775 A CN 104316775A CN 201410591468 A CN201410591468 A CN 201410591468A CN 104316775 A CN104316775 A CN 104316775A
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edge
resolution timer
pulse
time
timing
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CN104316775B (en
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刘宇杰
苏剑
刘振凯
李斌
姚骏
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University of Shanghai for Science and Technology
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University of Shanghai for Science and Technology
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Abstract

The invention provides a pulse signal cycle and duty ratio continuous measurement method. According to the method, the hardware functions of edge trigging units and timing units in existing high-precision timing chips are adopted, two high-precision timing chips are adopted, one high-precision timing chip measures the time spent by the pulse from the rising edge to the falling edge, the other high-precision timing chip measures the time spent by the pulse from the falling edge to the rising edge, and the two high-precision timing chips are made to work in the data measuring stage and the data transmitting and the initialization phase in an alternative mode. In this way, the advantages of the high precision of single measurement of the timing chips are utilized, the problem of continuously measuring the cycle and duty ratio of a set of pulse signals is solved, and the measuring accuracy is not lost.

Description

Pulse signal cycle and dutycycle method for continuous measuring
Technical field
The present invention relates to a kind of pulse signal cycle and dutycycle method for continuous measuring, particularly a kind of measuring accuracy that is applicable to requires to reach picosecond, needs to carry out method for continuous measuring to cycle of each pulse in set of pulses signal and dutycycle.
Background technology
Pulse signal applies more signal form in sensor and measuring instrument.The cycle of pulse and dutycycle then contain the much information of testee.The pulse signal such as, obtained after processing ultrasonic echo signal, its cycle and dutycycle can the density situations of reflected ultrasonic wave signal envelope, and then time matching method can be utilized to analyze the ultrasound wave flight time.Less demanding for measuring accuracy, and the cycle of more stable periodic pulse signal and duty ratio measuring have suitable proven technique.But when set of pulses signal is mixed with disturbing pulse, often needs cycle and the dutycycle that accurately can measure each input pulse, so just can adopt as time matching method etc. carries out statistical study to mass data.Therefore, a comparatively ideal pulse signal cycle and duty cycle measurement method are cycle and the dutycycles of each pulse in energy Measurement accuracy set of pulses signal.
In the measurement in cycle, the hardware capability of comparator unit and catcher unit in the timer of modern chip microprocessor can be make use of, such as the patent method for measuring pulse signal period (patent No.: 201010609782.0).
The method of measuring-signal dutycycle (duty cycle) mainly adopts counter at a high speed.The signal that measured signal can produce according to counter be distinguished into multiple interval uniformly, and to calculate measured signal in these multiple intervals be the number of high levle.Afterwards, then the number in interval and the number of high levle are divided by, to obtain dutycycle ratio.But measuring method traditionally, has its own shortcomings at least.
When utilizing the method meet just before a large shortcoming be that the method must adopt counter at a high speed.For example, if the frequency of measured signal is 1GHz (Gigahertz), and for this measured signal is distinguished into uniformly 100 interval time, under certain accuracy requirement, need speed up to the counter of 4GHz to I haven't seen you for ages.But, suitable high of the cost of high-speed counter.Traditional method of testing can make the cost of testing tool significantly promote.In addition, the capacity of counter also can be a restriction.If be the measured signal of 1GHz for frequency, and with the counter of above-mentioned 4GHz, carry out for time 1us (microsecond) measurement, then this counter at least needs the capacity of 4000.If need jumbo counter, the equally also problem of meet Lingao cost.Therefore, the problem that the restriction on capacity runs into when being equally also traditional measurement dutycycle.And when utilizing traditional measuring method, if cannot accurately carry out synchronous with the rising edge (raising edge) of measured signal or drop edge (falling edge) when measuring, the error producing a pulse during measurement may be made, to make in accuracy deviation to some extent.
The method of patent utilization frequency eliminator, voltage controlled oscillator and counter is had to ensure the accurate of measuring accuracy, such as patent duty cycle measurement system and its method (patent No.: 201010590871.5) for above problem.
But for set of pulses signal, to obtain cycle and the duty cycle information of wherein each pulse, then need to carry out continuous coverage to each pulse, clearly, traditional measuring method and existing technology also cannot meet this requirement.
Summary of the invention
The object of the invention is the deficiency existed for prior art, a kind of pulse signal cycle and dutycycle method for continuous measuring are provided, particularly a kind of measuring accuracy that is applicable to requires to reach picosecond, needs to carry out method for continuous measuring to cycle of each pulse in set of pulses signal and dutycycle, measure cycle and the dutycycle of each pulse in set of pulses signal exactly, measuring system can be adopted as time matching method etc. carries out statistical study to mass data.
For achieving the above object, design of the present invention is: adopt two high-precision timing chips, wherein a slice ranging pulse rising edge is to the time of negative edge, another sheet ranging pulse negative edge to the time of rising edge, and makes their alternations transmit and initial phase in DATA REASONING stage and data.Like this, just utilize the high-precision advantage of timing chip single measurement, solve the problem of set of pulses signal period and dutycycle continuous coverage, and the precision of measurement can not be lost.Said system takes full advantage of the high-precision advantage of timing chip single measurement and Modern microprocessor manipulates flexibly, eliminate the race problem of multiple interrupt program response, directly obtain the high-precision porch time by the hardware of special chip, thus high-precision recurrence interval and dutycycle can be obtained continuously.
According to the design of foregoing invention, the present invention by the following technical solutions:
A kind of pulse signal cycle and dutycycle method for continuous measuring, is characterized in that: adopt high-resolution timer 1 and high-resolution timer 2 and a data processing unit; High-resolution timer 1 has Start edge capture unit first, Stop edge capture unit first and timing unit first; High-resolution timer 2 has Start edge capture unit second, Stop edge capture unit second and timing unit second; The mistiming of timing unit first to the time of Start edge capture unit first input end S1 rising edge of a pulse change moment and Stop edge capture unit first input end S2 pulse falling edge change time instantaneously of high-resolution timer 1 carries out timing; The mistiming of timing unit second to the time of Start edge capture unit second input end S3 pulse falling edge change moment and Stop edge capture unit second input end S4 rising edge of a pulse change time instantaneously of high-resolution timer 2 carries out timing; Timing numerical value is sent into data processing unit by timing unit first and timing unit second respectively, high-resolution timer 1 and high-resolution timer 2 receive set of pulses signal X and alternation simultaneously, wherein the timing unit first of high-resolution timer 1 carries out timing to the rising edge of current PRF to time of negative edge, and the timing unit second of high-resolution timer 2 carries out timing to the negative edge of current PRF to time of rising edge; High-resolution timer 1 paired pulses rising edge to negative edge time timing while, the chronometric data of high-resolution timer 2 is sent into data processing unit and completes the initialization of high-resolution timer 2, high-resolution timer 2 paired pulses rising edge to negative edge time timing while, the chronometric data of high-resolution timer 1 sent into data processing unit and complete the initialization of high-resolution timer 1.Concrete operation step under pulse P (i) in set of pulses signal X and adjacent pulse P (i+1) thereof is as follows:
(a). when pulse P (i) rising edge in pulse signal X changes, the Start edge capture unit first of high-resolution timer 1 is triggered; When pulse P (i) negative edge in pulse signal X changes, the Stop edge capture unit first of high-resolution timer 1 is triggered; While Stop edge capture unit first is triggered, time T1 (i) of pulse P (i) rising edge through calculating to negative edge is sent into data processing unit and completes the initialization of high-resolution timer 2 by the timing unit first of high-resolution timer 1;
(b). when pulse P (i) negative edge in pulse signal X changes, the Start edge capture unit second of high-resolution timer 2 is triggered; When pulse P (i+1) rising edge in pulse signal X changes, the Stop edge capture unit second of high-resolution timer 2 is triggered; While Stop edge capture unit second is triggered, time T2 (i) of pulse P (i) negative edge through calculating to rising edge is sent into data processing unit and completes the initialization of high-resolution timer 1 by the timing unit second of high-resolution timer 2;
(c). repeat step (a) and (b), complete and P (i+1) rising edge is measured to the time T2 (i+1) of rising edge to the time T1 (i+1) of negative edge and negative edge;
(d). pulse P (i) rising edge high-resolution timer 1 and high-resolution timer 2 sent into of data processing unit was preserved to time of negative edge and negative edge to the time of rising edge, and waited for that the rising edge of next pulse P (i+1) is to time of negative edge and negative edge to the time data of rising edge.
(e). obtain cycle T (i)=T1 (the i)+T2 (i) of current PRF, dutycycle D=T1 (i)/T (i).
 
The present invention compared with prior art, has following apparent outstanding substantive distinguishing features and remarkable advantage:
The present invention takes full advantage of the high-precision advantage of timing chip single measurement and Modern microprocessor manipulates flexibly, eliminate the race problem of multiple interrupt program response, directly obtained the porch time of wide-range high-precision by the hardware of special chip, ensure that measuring accuracy can reach psec rank.And the alternation of two high-precision timing chips was transmitted and initial phase in DATA REASONING stage and data, meet the demand of continuous coverage cycle and dutycycle.These characteristics make to obtain the high-precision recurrence interval continuously and dutycycle becomes possibility.
Accompanying drawing explanation
Fig. 1 is the measure setup structural principle block diagram of one embodiment of the present of invention.
Embodiment
A preferred embodiment of the present invention is as following: see Fig. 1.
A kind of pulse signal cycle and dutycycle method for continuous measuring, adopt high-resolution timer 1 (1) and high-resolution timer 2 (2) and a data processing unit (3); High-resolution timer 1 (1) has Start edge capture unit first (1.1), Stop edge capture unit first (1.2) and timing unit first (1.3); High-resolution timer 2 (2) has Start edge capture unit second (2.1), Stop edge capture unit second (2.2) and timing unit second (2.3); The mistiming of timing unit first (1.3) to the time of Start edge capture unit first (1.1) input end S1 rising edge of a pulse change moment and Stop edge capture unit first (1.2) input end S2 pulse falling edge change time instantaneously of high-resolution timer 1 (1) carries out timing; The mistiming of timing unit second (2.3) to the time of Start edge capture unit second (2.1) input end S3 pulse falling edge change moment and Stop edge capture unit second (2.2) input end S4 rising edge of a pulse change time instantaneously of high-resolution timer 2 (2) carries out timing; Timing numerical value is sent into data processing unit (3) by timing unit first (1.3) and timing unit second (2.3) respectively.High-resolution timer 1 (1) and high-resolution timer 2 (2) receive set of pulses signal X and alternation simultaneously, wherein the timing unit first (1.3) of high-resolution timer 1 (1) carries out timing to current PRF rising edge to time of negative edge, and the timing unit second (2.3) of high-resolution timer 2 (2) carries out timing to current PRF negative edge to time of rising edge; While high-resolution timer 1 (1) paired pulses rising edge carried out to time of negative edge, the chronometric data of high-resolution timer 2 (2) is sent into data processing unit (3) and completes the initialization of high-resolution timer 2 (2), while high-resolution timer 2 (2) paired pulses negative edge carries out timing to time of rising edge, the chronometric data of high-resolution timer 1 (1) is sent into data processing unit (3) and completes the initialization of high-resolution timer 1 (1).Concrete operation step under pulse P (i) in set of pulses signal X and adjacent pulse P (i+1) thereof is as follows:
(a). when pulse P (i) rising edge in pulse signal X changes, Start edge capture unit first (1.1) of high-resolution timer 1 (1) is triggered; When pulse P (i) negative edge in pulse signal X changes, Stop edge capture unit first (1.2) of high-resolution timer 1 (1) is triggered; While Stop edge capture unit first (1.2) is triggered, time T1 (i) of pulse P (i) rising edge through calculating to negative edge is sent into data processing unit (3) and completes the initialization of high-resolution timer 2 (2) by the timing unit first (1.3) of high-resolution timer 1 (1);
(b). when pulse P (i) negative edge in pulse signal X changes, Start edge capture unit second (2.1) of high-resolution timer 2 (2) is triggered; When pulse P (i+1) rising edge in pulse signal X changes, Stop edge capture unit second (2.2) of high-resolution timer 2 (2) is triggered; While Stop edge capture unit second (2.2) is triggered, time T2 (i) of pulse P (i) negative edge through calculating to rising edge is sent into data processing unit (3) and completes the initialization of high-resolution timer 1 (1) by the timing unit second (2.3) of high-resolution timer 2 (2);
(c). repeat step (a) and (b), complete and the rising edge of P (i+1) is measured to the time T2 (i+1) of rising edge to the time T1 (i+1) of negative edge and negative edge;
(d). pulse P (i) rising edge high-resolution timer 1 (1) and high-resolution timer 2 (2) sent into of data processing unit (3) was preserved to time of negative edge and negative edge to the time of rising edge, and waited for that the rising edge of next pulse P (i+1) is to time of negative edge and negative edge to the time data of rising edge.
(e). obtain cycle T (i)=T1 (the i)+T2 (i) of current PRF, dutycycle D=T1 (i)/T (i).
 
Above-mentioned pulse signal cycle and dutycycle method for continuous measuring, the alternation of described two high-resolution timers was transmitted and initial phase in DATA REASONING stage and data.

Claims (1)

1. pulse signal cycle and a dutycycle method for continuous measuring, is characterized in that: adopt high-resolution timer 1 (1) and high-resolution timer 2 (2) and a data processing unit (3); High-resolution timer 1 (1) has Start edge capture unit first (1.1), Stop edge capture unit first (1.2) and timing unit first (1.3); High-resolution timer 2 (2) has Start edge capture unit second (2.1), Stop edge capture unit second second (2.2) and timing unit second (2.3); The mistiming of timing unit first (1.3) to the time of Start edge capture unit first (1.1) input end S1 rising edge of a pulse change moment and Stop edge capture unit first (1.2) input end S2 pulse falling edge change time instantaneously of high-resolution timer 1 (1) carries out timing; The mistiming of timing unit second (2.3) to the time of Start edge capture unit second (2.1) input end S3 pulse falling edge change moment and Stop edge capture unit second (2.2) input end S4 rising edge of a pulse change time instantaneously of high-resolution timer 2 (2) carries out timing; Timing numerical value is sent into data processing unit (3) by timing unit first (1.3) and timing unit second (2.3) respectively; High-resolution timer 1 (1) and high-resolution timer 2 (2) receive set of pulses signal X and alternation simultaneously, wherein the timing unit first (1.3) of high-resolution timer 1 (1) carries out timing to current PRF rising edge to time of negative edge, and the timing unit second (2.3) of high-resolution timer 2 (2) carries out timing to current PRF negative edge to time of rising edge; While high-resolution timer 1 (1) paired pulses rising edge carried out to time of negative edge, the chronometric data of high-resolution timer 2 (2) is sent into data processing unit (3) and completes the initialization of high-resolution timer 2 (2), while high-resolution timer 2 (2) paired pulses negative edge carries out timing to time of rising edge, the chronometric data of high-resolution timer 1 (1) is sent into data processing unit (3) and completes the initialization of high-resolution timer 1 (1); Concrete operation step under pulse P (i) in set of pulses signal X and adjacent pulse P (i+1) thereof is as follows:
(a). when pulse P (i) rising edge in pulse signal X changes, Start edge capture unit first (1.1) of high-resolution timer 1 (1) is triggered; When pulse P (i) negative edge in pulse signal X changes, Stop edge capture unit first (1.2) of high-resolution timer 1 (1) is triggered; While Stop edge capture unit first (1.2) is triggered, time T1 (i) of pulse P (i) rising edge through calculating to negative edge is sent into data processing unit (3) and completes the initialization of high-resolution timer 2 (2) by the timing unit first (1.3) of high-resolution timer 1 (1);
(b). when pulse P (i) negative edge in pulse signal X changes, Start edge capture unit second (2.1) of high-resolution timer 2 (2) is triggered; When pulse P (i+1) rising edge in pulse signal X changes, Stop edge capture unit second (2.2) of high-resolution timer 2 (2) is triggered; While Stop edge capture unit second (2.2) is triggered, time T2 (i) of pulse P (i) negative edge through calculating to rising edge is sent into data processing unit (3) and completes the initialization of high-resolution timer 1 (1) by the timing unit second (2.3) of high-resolution timer 2 (2);
(c). repeat step (a) and (b), complete and the rising edge of P (i+1) is measured to the time T2 (i+1) of rising edge to the time T1 (i+1) of negative edge and negative edge;
(d). pulse P (i) rising edge high-resolution timer 1 (1) and high-resolution timer 2 (2) sent into of data processing unit (3) was preserved to time of negative edge and negative edge to the time of rising edge, and waited for that the rising edge of next pulse P (i+1) is to time of negative edge and negative edge to the time data of rising edge;
?(e). obtain cycle T (i)=T1 (the i)+T2 (i) of current PRF, dutycycle D=T1 (i)/T (i).
CN201410591468.2A 2014-10-29 2014-10-29 Pulse signal cycle and dutycycle method for continuous measuring Expired - Fee Related CN104316775B (en)

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CN106569032A (en) * 2016-10-17 2017-04-19 长沙开元仪器股份有限公司 Signal frequency and duty ratio prediction method based on embedded microcontroller
CN106597122A (en) * 2017-01-10 2017-04-26 烟台大学 Radar and communication signal pulse width detection algorithm
CN109361500A (en) * 2018-10-25 2019-02-19 南通先进通信技术研究院有限公司 A method of the plesiochronous external pulse of self-correcting based on chip
CN117111537A (en) * 2023-10-23 2023-11-24 北京科泰克科技有限责任公司 Control system and method for hydrogen system based on hydrogen controller

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CN106569032A (en) * 2016-10-17 2017-04-19 长沙开元仪器股份有限公司 Signal frequency and duty ratio prediction method based on embedded microcontroller
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CN109361500A (en) * 2018-10-25 2019-02-19 南通先进通信技术研究院有限公司 A method of the plesiochronous external pulse of self-correcting based on chip
CN117111537A (en) * 2023-10-23 2023-11-24 北京科泰克科技有限责任公司 Control system and method for hydrogen system based on hydrogen controller
CN117111537B (en) * 2023-10-23 2024-01-26 北京科泰克科技有限责任公司 Control system and method for hydrogen system based on hydrogen controller

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