RU2598975C1 - Vernier recirculating time-code converter of high speed - Google Patents

Abstract

FIELD: measuring equipment.

SUBSTANCE: invention relates to measurement equipment and can be used for constructing digital converters of single nanosecond time intervals. Converter has a recirculator of start-pulse and a recirculator of stop-pulse, made on element OR, first input of which is connected to bus "stop-pulse" of the converter, second input - with the output of the delay line of stop-pulse, and the output - with the first input of an element AND, output of which is connected to the input of the delay line of stop-pulse and to the inverting input of pulses counter. Recirculator of start-pulse has an element OR, first input of which is connected to bus "start-pulse" of the converter, second input - with the output of the delay line of start-pulse, and the output - with the first input (m+1)-of the input element OR and with the input of the m-discharge delay line, m-outputs of which are connected to the D-inputs of appropriate m D-triggers and to the corresponding inputs (m+1)-of the input element OR, output of which is connected to the C-input of additional D-trigger and to the first input of the element AND, output of which is connected to the input of the start-pulse delay line, and the second input is connected to the second input element AND of the stop-pulse recirculator and with inverting output of additional D-trigger, D-input of which is connected to inverting input of the pulses counter of the stop-pulse recirculator, and the direct output - to the C-inputs of m-D-triggers, R-inputs of which are connected to the control input of the pulses counter 5, with R-input of additional D-trigger and with bus "initial plant" of the converter. At that the stop-pulse delay line of the stop-pulse recirculator has delay time equal to delay time of the start-pulse delay line of the start-pulse recirculator.

EFFECT: technical result is in increase of conversion performance m times.

1 cl, 2 dwg

Description

The invention relates to measuring equipment and can be used to build digital converters of single nanosecond time intervals (VI), specified by start and stop pulses in pulsed radar and radio navigation systems, including GLONASS and GPS systems, medical radars and lidars, with nano- and picosecond discreteness of conversion.

Known [1] is a converter (analog) having one recirculator used to recycle start and stop pulses and formed by the first OR circuit, the output of which is connected through the first delay line to the first input of the second OR circuit and through the second delay line to the second input of the second OR circuit, the output of which is connected to the first input of the first OR circuit and through a pulse divider with a counting input of the pulse counter, and the bus input of the converter is connected to the second input of the first OR circuit.

The disadvantage of this converter is the low speed of the conversion, due to the fact that the recirculation period must satisfy the condition t _n > 2t _xmax (where 2t _xmax is the largest value of the duration of the converted VI).

Known [2] is a converter (prototype) containing two recirculators, one of which serves to recycle a start pulse (recirculator of a start pulse), and the second one - a stop pulse (recirculator of a stop pulse) converted by a VI, each of which recirculators contains OR circuit, the first input which is connected to the input bus of the converter, the output - with the first input of the And circuit, the output of which through the delay line is connected to the second input of the OR circuit, and the second inputs of the And circuit of both recirculators are combined and connected to the output of a recirculator, the first input of which is connected to the output of the start pulse circuit And recirculator, the second input - to the output of the stop pulse circuit And recirculator and to the counting input of the pulse counter, the control input of which is connected to the third input of the recirculator operation control unit and to the converter control bus .

The disadvantage of this converter is also the low conversion speed.

The aim of the invention is to increase the speed of conversion.

This goal is achieved in that the duration of the start pulse in each of the recirculations in the start pulse recirculator is sequentially expanded by a calibrated value of duration equal to m × τ (τ is the resolution of the transformation, am = 2,3,4, ..., any integer) until they coincide with the stop pulse recirculating in the stop pulse recirculator without changing its initial duration, while the periods of recirculation of start and stop pulses must be strictly equal to each other.

In FIG. 1 is a functional diagram of a vernier recirculation time-code converter of increased speed, and in FIG. 2 - time diagrams of his work.

The high-speed vernier recirculating time-code converter (PVC) contains a start pulse recirculator and a stop pulse recirculator made on the OR1 element, the first input of which is connected to the converter “stop-pulse” bus 2, the second input - with the output of 3 stop delay lines -pulse, and the input is with the first input of the I4 element, the output of which is connected to the input of the delay lines 3 of the stop pulse and to the counting input of the pulse counter 5, the start-pulse recirculator contains the OR6 element, the first input of which is connected by a 7 "old t-pulse ”of the converter, the second input with the output of the delay line 8 of the start pulse, and the output with the first input of the (m + 1) -input element OR9 with the input of the m-tap delay line 10, the m-outputs of which are connected to D- the inputs of the corresponding from m D-flip-flops 11.1 ÷ 11.m and to the corresponding inputs of the (m + 1) -input element OR9, the output of which is connected to the C-input of the additional D-trigger 12 and to the first input of the I13 element, the output of which is connected to the input delay line 8 of the start pulse, and the second input with the second input of the stop pulse recirculator element I4 and with with the output of the additional D-flip-flop 12, the D-input of which is connected to the counting input of the pulse counter 5 of the stop pulses recirculator, and the direct output is connected to the C-inputs of m D-flip-flops 11.1 ÷ 11.m, the R-inputs of which are connected to the control input pulse counter 5, with the R-input of an additional D-flip-flop 12 and with bus 14 “initial setting” of the converter.

Consider the operation of the proposed Converter. Before starting the conversion with the control signal supplied to the converter bus 14, the D-flip-flop 12 opens the start-pulse recirculator and the stop-pulse recirculator, and also sets the pulse counter 5 and the memory register on the D-flip-flops 11.1 ÷ 11.m state is logical zero, that is, in the initial state.

Start and stop pulses corresponding to the beginning and end of a converted waveform with a duration of tx are fed to the buses of the “start pulse” 7 and “stop pulse” 2, respectively, and must have calibrated values of the duration tst> (tp + τ) and tsp> (tp2 + τ), where tp ₁ = tp ₆ + tp ₉ + tp ₁₃ , tp ₂ = (t ₁ + t ₄ ) is the total delay time of switching logic elements, respectively, of the start-pulse recirculator of the element OR6, (m + 1) - input element OR9, element I13 and stop pulse recirculator (element OR1, element I4), and τ is the delay time between the taps of the m-tap line LCD 10, is selected equal to the required resolution of the conversion resolution. From the moment a start pulse tst arrives on the “start pulse” bus 7, an impulse sequence with a period Tst and pulse duration in each of the recirculation tst = tst + imτ is generated at the output (m + 1) of the input element OR9 of the start pulse recirculator, where i = 1,2,3, ..., Nst - serial number of recirculation in the start-pulse recirculator (Fig. 2 e). The value of Tst is set by the delay time tlz _{8 of} the delay line 8 of the start pulse as Tst = tlz ₈ .

At the same time, the stop pulses tsp are recycled in the stop pulse recirculator with the period Tsp = tlz ₃ , (tlz ₃ is the delay time of the delay line 3 of the stop pulse recirculator), but at the same time its initial duration remains unchanged, i.e. tspi = tsp (Fig. 2 e).

To ensure the condition of operability of the converter in the range tx∈ [tx _min ; tx _max ] it is necessary to strictly fulfill the condition Tst = Tsp> tx _max (or tlz ₈ = tlz ₃ > tx _max ).

Since in each of the recirculations the start pulse sequentially expands by m × τ, there is a time moment tcoв when the pulses tst _i and tsp coincide (Fig. 2 e, e). The coincidence time (tcoev) is recorded by an additional D-flip-flop 12 (Fig. 2 g) and the recirculation process in the start and stop pulses is stopped, and in the pulse counter 5 the number of recirculation n _sp stop pulses will be fixed, which corresponds to a coarse digital estimating a time interval of duration tx (Fig. 2 e). At the same time, in the memory register made on D-flip-flops 11.1 ÷ 11.m, at the time tсs, the pulse sequences recorded from the taps of the m-tap delay line 10 are fixed (Fig. 2 b, c, d). The number of taps η (range of variation η∈ [1 ÷ m]), the pulse sequences from which were not recorded in the memory register, will be a digital refinement of a rough digital estimate of the VI with a duration of tx.

Thus, the proposed nonius recirculation time-code converter at the beginning roughly, with discreteness (m × τ), and then precisely, with discreteness τ, transforms the WI of duration tx into a digital code. The conversion function is described by the expression:

t _x = n _sp × mτ + ητ + t

Taking tst = N _O × τ, where N _O is the digital value of the calibrated value of the start pulse duration tst, which is determined during the configuration of the converter.

t _x = {n _sp × m + N _O + η} τ = N × τ.

The digital conversion result N is determined in the arithmetic logic device, which in FIG. 1 conventionally not shown. Conversion time of the proposed converter

Tpr≥tx _max + n _sp T _sp .

While the conversion time of the prototype Converter has the form:

TPR _p ≥tx _max + m × n _sp T _sp .

Since tx _max <Tsp then Tpr≥n T _{cn cn} and Tpr _n ≥m × n _{cn cn} T and therefore, the proposed converter has m times smaller than the conversion time.

Compared with the prototype, the proposed technical solution has m times higher speed, that is, the purpose of the invention is to increase the speed of conversion is achieved.

Information sources

1. USSR author's certificate No. 654932, cl. G04F 10/00. The method of measuring time intervals / N.R. Karpov; application 07/11/77. publ. 03/30/79, Bull. No. 12.

2. Maleshko EA Integrated circuits in vernier nuclear electronics. - Ed. 2nd, add. M .: Atomizdat, 1987 .-- S. 146 ÷ 147, fig. 3.15.

Claims (1)

Vernier recirculating time-code converter of increased speed, comprising a start pulse recirculator and a stop pulse recirculator made on an OR element, the first input of which is connected to the converter “stop pulse” bus, the second input is with the output of the stop pulse delay line, and output - with the first input of AND element, the output of which is connected to the input of the stop pulse delay line and to the counting input of the pulse counter, characterized in that in order to increase the conversion speed of the start-pulse recirculator contains an OR element, the first input of which is connected to the "Start-pulse" bus of the converter, the second input - with the output of the start-pulse delay line, and the output - with the first input of the (m + 1) -OR input element and with the input of the m-tap line delays, the m-outputs of which are connected to the D-inputs of the corresponding m-D flip-flops and to the corresponding inputs of the (m + 1) -input OR element, the output of which is connected to the C-input of the additional D-trigger and to the first input of the And element, output which is connected to the input of the delay line of the start pulse, and the second input to the second input the home of the stop pulser AND element of the stop pulses and with the inverse output of an additional D-trigger, the D-input of which is connected to the counting input of the counter of pulses of the stop pulses and the direct output to the C-inputs of m D-flip-flops, the R-inputs of which are connected to the control input of the counter of the pulses of the stop pulse recirculator, with the R-input of the additional D-flip-flop and with the bus "initial setting" of the converter, and the stop line of the stop pulse of the stop pulse recirculator has a delay time equal to the delay time of the start-pulse delay line recirculator start pulse.

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