SU842853A1 - Amplitude-to-pulse function generator - Google Patents

Description

(54) AMPLITUDE-PULSE FUNCTIONAL CONVERTER

one

/

The invention relates to automation and computer technology and can be used in hybrid information transmission and processing systems for reconstructing and reproducing functions of an analog signal by a sequence of its selective values, in particular, by interpolating functions using Newton's formula.

A device for reproducing functions is known comprising controllable keys, a digital-to-analog converter, a low-pass filter, counters, a pulse generator, a descrambler, and memory elements.

The drawback of the device is a reduced accuracy of reproduction and restoration of intermediate values of a function between its selective values.

Also known is the amplitude of the bottom-pulse functional transducer, comprising a pulse generator, a counter, a control unit, digital analogue converters, controllable keys, integrators, memory elements, and an output adder G21.

A disadvantage of the converter is also the reduced accuracy of the reproduction of functions.

The closest to the proposed is an amplitude-pulse functional converter containing an output adder, n keys. Records (where n is the number of function samples in the current playback interval) connected by signal inputs to the device input, and output of every 1st (1 i n ) key

0 records through the i-th memory cell to the signal input of each i-th read key and read key groups, the outputs of which are connected to the corresponding inputs of the first

5 of the intermediate adder, with the control inputs of the write and read keys connected to the corresponding outputs of the control unit, and the inputs of the output adder are connected

0 with the outputs of the first intermediate adder and integrator connected by inputs to the outputs of the corresponding read keys and to one of the inputs of the first intermediate sum 5 of the mat, connected to the outputs of the corresponding read keys through the inverter GZ.

The disadvantage of this invention is the reduced accuracy of reproduction of functions, which is due to

0

using low-order approximating polynomials and analog elements to reconstruct the values of the reproduced functions.

The purpose of the invention is to improve the accuracy of reproduction of functions. For this purpose, an amplitude-pulse functional converter containing an output adder, n recording keys (where n is the number of function samples in the current playback interval) connected by signal inputs to the device input and the output of each i-th (1-s S n) key records through the i-th memory cell are connected to the signal input of each 1st read key and n read key groups, the outputs of which are connected to the corresponding inputs of the first intermediate adder, and the control inputs of the write and read keys are connected to The relevant outputs of the control unit include (p-2) additional adders, (p-2) code converters, (p-1) controllable voltage dividers, pulse generator and a counter connected by input to the output of the pulse generator, and output to the inputs code converters and with the control input of the first controlled voltage divider connected by a signal input to the output of the first intermediate adder, the output of each j-ro (1 jf J n-2) code converter connected to the control input (j + l) - ro controlled voltage divider, connected by a signal input to the output J-ro of an additional adder, and the inputs of each additional adder are connected to the outputs of the corresponding read keys of the n read key groups, and the remaining inputs of the output adder are connected to the outputs of the controlled voltage divider.

The drawing shows a block diagram of a converter for a case, i.e. for the case of interpolating functions according to the Newton formula of the 2nd order. .

Pulse amplitude function, the converter in this case contains keys of 1, 2/13 records (according to the number of samples of the function at the current playback interval) connected by signal inputs to input 2 of the device. The output of each key l, - (1 i and 3) is connected via the memory cell 3 PJ with the signal input of each g key 4 J readings of three groups of the read key. The control inputs of all keys 1 and 4 are connected to the corresponding outputs of the control unit 5. Counter 6 is connected by a counting input to the output of the generator 7 pulses, and inlet to the input of the converter 5

codes and with the control input of the first inputted divider 9 voltage i connected by the signal input to the output of the additional adder 12. The first input of the output adder 13 and the input of the intermediate and additional adders 12 and 13 are connected to the corresponding outputs of the keys 4 of the three groups of read keys iOtherly The adder 13 is connected to the outputs of the dividers 9 and 11 of the voltage. The control unit 0 5 can be implemented, for example, a clock generator 14, a delay element 15, an annular shift register 16 and AND 17 elements. A converter of 8 codes, 5 that performs a quadratic conversion of the output code of counter 6, can be performed, for example, in the form of a static code converter on the OR elements, the inputs and outputs of which are connected to the corresponding inputs and outputs of the bits of the converter 8. Memory cells 3 can be executed on capacitors and isolating operational amplifiers.

 The Converter operates as follows.

Input 2 receives samples of the function. The control unit 5 generates a sequence of command pulses, 0 controlling the operation of the recording keys 1, providing for recording and updating information about the selected function samples used to restore the function in the current playback interval. The output voltage is generated from three samples of the input signal in accordance with Newton’s second-order formula.

U (t, +. Trh) U, - + t (2U, - - | Ul-l 42 +

+,

where h is the sampling period of the input signal;

f t - „, t

From € Go, 1 ..

In accordance with this formula, the control unit 5 performs, simultaneously with updating information 0 in the memory cells 3, reading the filled values of the input signal samples to the inputs of the adders 10, 12 and 13. In each reading cycle, the first input of the adder 13 is zero The Newton's formula from the output of the corresponding: 4 readout keys, to the second input of the adder 13 is linear with the voltage from the output of the voltage divider 9, and to the third input is quadratic — composed from the output of the divider 11. The adders 10 and 12 carry out dissolved prior otschetyv weighted summation. input signal. the required linear and quadratic variation of these 5 weighted sums in each interval

reproduction is carried out by changing the transmission ratios (equal voltage dividers 9 and 11. In particular, the transfer ratio of the divider .9 depends linearly on the size of the code accumulated in the counter 6, and the transfer ratio of the divider 11 is quadratically, while the frequency of the pulses, arriving at the input of counter 6 from generator 7 is 2 times higher than the sampling rate of the input signal (where 1 is the size of counter 6).

Thus, the proposed device allows, in comparison with the known, to increase the accuracy of reproduction of functions both by increasing the order of approximating -polynomials used, and due to the digital nature of the formation of sweep signals at current reproduction intervals,

Claims (3)

Invention Formula Amplitude-pulse functional converter containing an output adder, n recording keys (where n is the number of function samples in the current playback interval) connected by signal inputs to the device input, and the output of every 1st (1 g n) recording key via the -th cell the memory is connected to the signal input of each: first 1 read key n read key groups | whose outputs are connected to the corresponding inputs of the intermediate adder, and the control inputs of the write keys The readings are connected to the corresponding DIM outputs of the control unit, which are used in order to increase the accuracy of the reproduction of the functions, (n-2) additional extenders (n-2) of code converters, (n-1) / controlled voltage dividers, pulse generator and counter connected to the output of the pulse generator, and output to the inputs of code converters and to the control input of the first controlled voltage splitter connected by a signal input to the intermediate adder, and the output of each The second J th (1 4 J p - 2) code converter is connected to the control input (j + l) -ro of the controlled voltage divider connected by the input to the output J of the additional adder, and the inputs of each additional adder and the first input of the output adder is connected to the outputs of the corresponding read keys of the n read key groups, and the remaining inputs of the output adder are connected to the output of the controlled voltage dividers. Sources of information taken into account in the examination 1, USSR Copyright Certificate No. 2516796 / 18-24, cl. G 06 6 7/26, 1977. 2. Authors certificate of the USSR 546899, cl. G 06 G 7/26, 1974. 3. USSR author's certificate And 691881, cl. G 06 G 7/30, 1977 (prototype),