RU2490684C1 - Method of recirculation conversion of nanosecond-duration intervals into digital code - Google Patents

Abstract

FIELD: instrument making.

SUBSTANCE: invention may be used for digital conversion of single nanosecond-duration time intervals set by start-and-stop pulses of nano- and subnano-quantisation of conversion in navigation and control systems, determination of integrated circuit parameters and analysis of various physical and technological processes. Recycling of start-and-stop pulses of initial calibrated duration is performed at recycling period equal to T+τ and T-τ, respectively. Note here that their durations in every recycle does not vary. Note also that digital result of conversion defines doubled magnitude of calculated number of recycles performed by start-and-stop pulses after start of recycling and to coincidence of recycling start-and-stop pulses.

EFFECT: faster conversion.

Description

The invention relates to information-measuring equipment and can be used for digital conversion of single time intervals of nanosecond duration, given by start and stop pulses, with nano- and subnanosecond resolution of the conversion in navigation systems, control, determination of integrated circuit parameters, the study of various physical and technological processes.

There is a method of recirculating conversion of time intervals (TI) specified by start and stop pulses, based on their recirculation in one recirculator, and in each of the recirculations the duration of start and stop pulses increases by a calibrated value of τ, equal to the resolution of the conversion, and counting the number of perfect recirculations until the moment of coincidence of the recirculating pulses [1].

The disadvantage of this method is the long conversion time, due to the fact that the recirculation period must satisfy the condition T> 2t _Xmax where t _Xmax is the largest value of the duration of the converted VI.

A known method (prototype) based on recirculation in one recirculator with a recirculation period T> t _{Xmax of} start and stop pulses of the initial calibrated duration corresponding to the beginning and end of the converted VI, with an increase in the initial calibrated start pulse duration by a calibrated value of the duration τ in each recirculation, and the stop pulse of the initial calibrated duration - without changing its duration in each of the recirculations, until the time of coincidence of the recirculating start and stop pulses, and counting the number of recirculation performed by a stop pulse of the initial calibrated duration [2].

The disadvantage of this method is the large conversion time.

The aim of the proposed method is to reduce the conversion time.

This goal is achieved in that the start and stop pulses of the initial calibrated duration, corresponding to the beginning and end of the converted time interval, are subjected to recirculation in one recirculator, moreover, with a recirculation period T-τ of the stop pulse, the initial calibrated duration, and the recirculation period start the pulse of the initial calibrated duration is chosen equal to T + τ, where τ is the resolution of the conversion, the number of recirculations performed by the stop pulse of the initial calibrated duration from the moment is calculated the beginning of the recirculation and until the recirculating start and stop pulses coincide, and the digital conversion result is defined as the double value of the calculated number of recirculations.

The essence of the method of recirculating conversion of time intervals of nanosecond duration to a digital code is as follows.

The start and stop pulses of the initial calibrated duration t _H and t _K , corresponding to the beginning and end of the transformed VI, duration t _X , are sent to the recirculator.

Start and stop pulses must have equal calibrated values of duration t _H = t _K > t _P + τ, where t _P is the total switching time of the logic elements of the recirculator. The start pulse t _{H is} subjected to recirculation with a period (T + τ), as a result, a monotonic pulse sequence is generated in the recirculator:

f _H (t) = f (t _H + n _n (T + τ)),

where n _H is the number of start-pulse recirculations.

Simultaneously, in the recirculation process with a recirculation period T-τ of a stop pulse of the initial calibrated duration t _K , a monotonic pulse sequence is generated in the recirculator:

f _K (t) = f (t _K + n _k (T-τ)),

where the number of stop-pulse recirculations is n _к = n _n = n, and T> t _Xmax .

At the time point f _H (t) = f _K (t), that is, when the trailing edge of the recirculating start pulse coincides with the leading edge of the recirculating stop pulse, the count of the number of recirculations n of the stop pulse (or start pulse) of the initial calibrated duration from the moment they enter the recirculator, it stops.

The conversion function of the proposed method has the form:

t _X = 2nτ = βτ, where the range of variation is n∈ [1; N / 2] (N = t _Xmax / τ), and the digital conversion result β is defined as the double value of the counted number of stop pulse recirculations.

The conversion time of the proposed version of the conversion method:

T _CR = t _Xmax + (T-τ) N / 2≈N / 2 t _Xmax , and methods (prototype)

T ^* _{pr =} (N + l) t _Xmax ≈N t _Xmax .

Then the time gain of the conversion of the proposed method is equal to:

K = T ^* _pr / T _pr = N / (N / 2) = 2.

Thus, the proposed conversion method has half the conversion time.

Literature

1. A.S. USSR No. 654932, M.cl. G04F 10/00.

2. RF patent No. 2443007, M.cl. G04F 10/00.

Claims (1)

The method of recirculating conversion of time intervals of nanosecond duration to a digital code based on the recirculation in one recirculator of start and stop pulses of the initial calibrated duration, corresponding to the beginning and end of the converted time interval, characterized in that, in order to reduce the conversion time, the values of the start- and stop pulses of the initial calibrated duration in each of the recirculations are left unchanged, the recirculation period of the start pulse of the initial calibrated the duration is chosen equal to T + τ, the period of recirculation of the stop pulse of the initial calibrated duration is chosen equal to T-τ, where τ is the resolution of the conversion, the number of recirculations performed by the stop pulse of the initial calibrated duration from the moment the recirculation begins to the moment the recirculating start and stop pulses, and the digital conversion result is defined as the double value of the calculated number of recirculations made by the stop pulse of the initial calibrated duration.