Poisson pulse stream generator

FIELD: measurement technology; pulse stream generators.

SUBSTANCE: proposed Poisson pulse stream generator has k + 1 memory devices, comparison unit, k digital-to-analog converters, control circuit, register, counter, selector, k bell-shaped pulse generators, adder, voltage-to-current converter, and clock generator.

EFFECT: enlarged generation range of pulses adequate to ionization chamber signals.

1 cl, 2 dwg

The invention relates to measuring technique and can be used as a generator Poisson pulse stream with the parameters of the pulses, adequate or close to the signal parameters of the ionization chamber.

Known generator quasiresonance pulse stream [1], containing the pulse generator, the generator of pseudorandom, uniformly distributed numbers, the comparison circuit, the first and second digital-analog converters, elements, AND IS NOT, a one-shot, managed key, inverter voltage, frequency, delay element and a reversible counter.

The disadvantage of this generator is that it does not allows to specify an arbitrary distribution of amplitudes and intervals, and independently adjust the intensity (average frequency) of the pulse.

Known generator quasiresonance pulse stream [2], consisting of a pulse generator, generator, pseudo-random, uniformly distributed numbers, the first and second storage devices, the block comparison of the first and second elements of the delay register, a digital-to-analogue Converter, counter, first and second elements AND IS NOT, a third delay elements, the one-shot and managed key.

The disadvantage of this generator is that it has a low maximum intensives and pulse (no more than 2· 10⁴with^-1), does not ensure the formation of superimposed pulses, and the distribution of the number of occurrences of pulses is significantly different from Poisson, namely, the ratio of mean to standard deviation equal to ≈0,52.

The objective of the invention is the creation of a Poisson generator pulse output, providing the possibility of formation of k superimposed pulses and increase the maximum intensity of the generated pulses.

The result of the use of the invention is the expansion of the range of pulse-forming, an adequate signal of the ionization chamber.

The technical result is achieved due to the fact that in the known device, comprising a generator of clock pulses, the first storage device, digital to analog Converter, the second storage device, the register block comparison, the counter, and the output of the generator of clock pulses connected to the input counter and the output of the second storage device connected to the input of the register, inputs: control circuit, the selector k shapers bell-shaped pulses, the k-1 additional storage devices, k-1 additional digital-to-analogue converters, the adder and the Converter voltage - current. It is proposed between these blocks Khujand shall implement the following link. The input control circuit connected with highway ISA computer. The first k outputs of the control circuit connected with the first input of the first and the first inputs of the k-1 additional storage devices, and the last output control circuit connected to the first input of the second storage device. An output register connected to the first input of the comparison to the second input of which is to connect the output of the counter. The output of the Comparer to connect with the second input of the counter, the second input of the second storage device and to the input of the selector. To the outputs of the selector will be prompted to connect to the second input of the first and second inputs of the k-1 additional storage devices. The output of the first storage device through the first d / a Converter and the first shaper bell-shaped pulses be connected to the first input of the adder, and the output of each of k-1 additional mass storage devices to connect to the input of your digital to analogue Converter.

The output of each of k-1 d / a converters through your shaper bell-shaped pulses to be connected to the appropriate input of the adder. Finally, the output of the adder to combine with the Converter voltage - current. The inverter output voltage - current is the generator output Poisson pulse stream.

Signs, tocause offer generator prototype - the presence of a control circuit, a selector, k shapers bell-shaped pulses, k-1 d / a converters, k-1, additional storage devices, adder and inverter voltage - current - cause the increase of performance in respect of the maximum value of the generated intensities, due to the fact that the numbers recorded in all storage devices formed in advance and, thus, are excluded hardware delays caused by the formation of the necessary signals.

Figure 1 shows the circuit of the generator Poisson pulse stream, where 1 is the generator of clock pulses, 2 - control scheme, 3.1 first storage device, 3.2-3.k - additional storage devices 4.1-4.k - analog converters, 5.1-5.k - shapers bell-shaped pulses, 6 - adder, 7 Converter voltage - current, 8 - second storage device, 9 - case 10 - block comparison, the 11 - count, 12 - selector.

Figure 2 shows a time chart explaining the operation of the generator Poisson pulse stream.

Explain the purpose of the individual blocks of the proposed generator.

Storage devices 3.1-3.k are used to write the array of N uncorrelated binary numbers with a normal distribution. The second storage device 8 is written N ncorr the profiled binary numbers from the Poisson distribution.

The output of clock 1 is connected to the first input of the counter 11. The first k outputs of the control circuit 2 is connected with the first inputs of the storage devices 3.1-3.k, the outputs are connected to corresponding inputs of digital to analog converters 4.1-4.k. Each d / a Converter 4.1-4.k associated with his driver 5.1-5.k bell-shaped pulses, the outputs of each driver 5.1-5.k connected to respective inputs of the adder 6 is connected in series with the Converter 7, the voltage - current. The inverter output 7 voltage - current is the generator output Poisson pulse stream.

The last output of the control circuit 2 is connected to the first input of the second storage device 8, the output of the storage device 8 via the register 9 is connected to the first input unit 10 comparison, the second input is connected with the output of the counter 11. The output of the Comparer 10 is connected to a second input of the counter 11, the second input of the storage device 8 and the input of the selector 12. The outputs of the selector 12 is connected to the second inputs of the storage devices 3.1-3.k.

The generator works as follows.

Before working in the storage device 3.1,...3.k through highway ISA and the control circuit 2 is written to the array of N uncorrelated binary numbers with a normal distribution. P is item, in the particular case when N=2ⁱand k=2^jwhere ij=1, 2, 3,... are integers, the storage device records number: 3.1 written 1, k+1, 2k+1,...,N-k+1, 3.2-2, k+2, 2k+2,..., N-k+2; 3.k-k, 2k, 3k,...N.

The second storage device 8 is written N uncorrelated binary numbers from the Poisson distribution.

After recording, the signal control circuit 2 in register 9 from the storage device 8 is loaded first binary number, and the counter 11 receives from the clock 1 clock pulses with a frequency f and the counter 11 loops through all the code combinations. At the time of coincidence number counter 11 with the number recorded in the register 9, the output of the Comparer 10, a signal is generated which is fed simultaneously to the second input of the counter 11, thereby establishing it in its original state and ready for the next account; to the input of the selector 12 and to the second input of the second storage device 8, thereby allowing reading of the second number. The generator operation is repeated up until the second storage device 8 will not read all N numbers and, thus, at the output of the Comparer 10 is formed of N successive pulses which are fed to the selector 12. The selector 12 generates k parallel signals, which of the storage devices 3.1,...,3.k sequentially in time for the implementation of the is code reading, corresponding to the amplitudes of the generated pulses, which are fed to the input of the corresponding digital-to-analogue converters 4.1-4.k. The pulses from the outputs of digital to analog converters 4.1-4.k come to the shapers 5.1-5.k, the output of which is formed a bell-shaped pulses, identical in form to the pulse ionization chamber.

With outputs shapers 5.1-5.k pulses are received at the respective inputs of the adder 6, the output of which the resulting pulse is supplied to the inverter 7, the voltage - current.

Thus, at the output of the Converter 7 the value of the charge converted pulse corresponds to the magnitude of the charge pulse ionization chamber.

Figure 2 shows a time chart explaining the operation of the device for the case j=2 (when hardware implementation of this generator was made i=28 and j=2).

The average duration of the time interval T_CPpulse at the output of the Comparer 10 is determined in the process of recording the second storage device 8 by a set of binary numbers and clock frequency f and intensity (average frequency) f_CPoutput is f_CP=1/T_CP.

The duration of the pulses at the output of shaper 5.1-5.k is 120 NS and, therefore, the output of the comparison circuit 10 decreases when the interval between pulses less than 120 NS, is and the output of the adder happen two, three - etc. multiple overlapping pulses, adequate overlap of the pulses in the ionization chamber, which is at the above numbers reflect the real levels of loading 10⁷pulse/S.

Thus, the proposed generator Poisson pulse stream can ensure the formation of pulses, adequate signals from the ionization chamber in a wide range with a given Central frequency, the formation overlays a given k number of pulses and a Poisson distribution of the number of occurrences of pulses is the ratio of mean to standard deviation equal 1,01.

Sources of information

1. Inventor's certificate SU # 1195432, N 03 To 3/84, 1984.

2. Inventor's certificate SU # 1274129, N 03 To 3/84, 1986 (prototype).

Generator Poisson pulse stream comprising a generator of clock pulses, the first and the second storage device, the block comparison, digital to analog Converter, the register and the counter, and the output of the generator of clock pulses is connected to the counter, and the output of the second storage device is connected to the input of the register, characterized in that it additionally introduced the control circuit, the selector k shapers bell-shaped pulses, k-1 d / a converters, k-1, additional storage devices, the adder and conversion on the tel voltage - current, and an input control circuit connected to the line ISA computer; the first k outputs of the control circuit connected to the first input of the first storage device and the first input of the k-1 additional storage devices, and the last output control circuit connected to the first input of the second storage device; an output register connected to the first input unit of the comparing, a second input connected to the output of the counter; the output of the Comparer is connected to a second input of the counter, the second input of the second storage device and to the input of the selector; the outputs of the selector is connected to the second input of the first storage device and the second inputs of the k-1 additional storage devices; the outputs of the first and each of k-1 additional storage devices are connected to the inputs of their digital to analogue Converter, the output of each digital-to-analogue Converter connected to the input of your shaper bell-shaped pulse, the output of each shaper bell-shaped pulse is connected with the corresponding input of the adder, the output of which is connected to the input of the Converter voltage - current; the output of the inverter is the output of the generator Poisson pulse stream.