SU1570026A2

SU1570026A2 - Device for detecting telephone signal

Info

Publication number: SU1570026A2
Application number: SU884486151A
Authority: SU
Inventors: Ефим Исаакович Мольвер
Original assignee: Всесоюзный Научно-Исследовательский Институт Железнодорожного Транспорта
Priority date: 1988-08-15
Filing date: 1988-08-15
Publication date: 1990-06-07

Abstract

Изобретение относитс к области электросв зи. Целью изобретени вл етс повышение точности обнаружени . Устройство содержит входной усилитель 1, выделитель 2 слоговой огибающей, первый 3 и второй 8 компараторы, первый 7 и второй 4 элементы ИЛИ, первый 5 и второй 13 элементы И, элемент 6 задержки пауз, источник 9 опорного напр жени , выпр митель 10, первый 11 и второй 12 элементы задержки. Цель достигаетс путем исключени потерь полезного сигнала, дл чего введены генератор 19 тактовых импульсов и последовательно соединенные АЦП 14, блок 15 задержки, ЦАП 16, выходной усилитель 17 и ключ 18. 1 ил.The invention relates to the field of telecommunications. The aim of the invention is to improve the detection accuracy. The device contains an input amplifier 1, a selector 2 of a syllable envelope, the first 3 and second 8 comparators, the first 7 and second 4 elements OR, the first 5 and second 13 elements AND, the delay element 6 delays, the source 9 of the reference voltage, the rectifier 10, the first 11 and second 12 delay elements. The goal is achieved by eliminating the loss of the useful signal, for which a clock pulse generator 19 and a series-connected ADC 14, a delay unit 15, a DAC 16, an output amplifier 17 and a switch 18 are inputted. 1 Il.

Description

The invention relates to the field of telecommunications. The aim of the invention is 2

There is an increase in detection accuracy. The device contains an input amplifier 1, a selector 2 of a syllabic envelope, the first 3 and second 8 comparators, the first 7 and second 4 elements OR, the first 5 and second 13 elements AND, the delay element 6 pauses, the reference source 9, the rectifier 10, the first 11 and second 12 delay elements. The goal is achieved by eliminating the loss of the useful signal, for which a clock pulse generator 19 and a series-connected ADC 14, a delay unit 15, a DAC 16, an output amplifier 17 and a key 18, 1, or

with

"five

5 C „„ 1570026

1570026

The invention relates to telecommunications and is an improvement of the device on the autor., № 965012.

The aim of the invention is to improve the detection accuracy by eliminating the loss of the useful signal.

The drawing shows a block diagram of a device for detecting a television signal. Ιθ

; The device for detecting a telephone signal contains an input amplifier 1, a selector 2 of the syllable envelope, the first comparator 3, the second element OR 4, the first element AND 5, 1.5

the pause delay element 6, the first element OR 7, the second comparator 8, the voltage source 9, the rectifier 10, the first delay element 11, the second delay element 12, the second 20 And 13 element, the analog-to-digital converter 14, the 'delay unit 15, digital-to-analog converter 16, you-. power amplifier 17, key 18, generator 19 clock pulses, node 20 25

processing,

The invention consists in the following.

The input speech signal amplified by the input amplifier 1 is received temporarily in node 20 and input to the analog-digital converter 14, where it is digitized and then delayed! in block 15 without distortion of the waveform, In node 20, at this time processing of the input signal is being performed for the purpose of detecting or distinguishing it. In this case, it becomes possible to reduce the passband of the separator to 2 Hz, to 40

thus detection accuracy, the device operates as follows, 45

At the output of the selector 2, an envelope signal is extracted, which is converted by means of comparators 3 and 8 into the corresponding unipolar discrete signals. Source 9 determines the thresholds for the comparators 3 and 8, from the outputs of which the signals from the envelope in discrete form are fed to the inputs of element 4 with a delay of about 4050 ms. Having passed through element 4, the signal

appears at the inputs of elements 5 and 13. At the same time, the input signal is rectified in the rectifier 10 and enters element 11, where it is delayed by 40-50 ms. Thus, after 40-50 ms the signal appears at the output of element 5 and further, turning on element 6, obtained the control signal passes through the element 7 to the control input of the key 18, opening the latter. The combination of elements 12 and 13 is designed to reduce the effect of interference on the delay time of element 12,

Simultaneously with the process described, the input speech signal is converted into analog-to-digital converter 14 into digital form, delayed for up to 64 ms in block 15, converted into digital-analog converter 16 back to analog form, amplified by output amplifier 17 and fed to information input of key 18, Since by this time the key 18 is already open, the speech signal is freely and without distortion through the key 18 arrives at the output of the device to detect the telephone signal. The · 19 generator, constantly generating clock pulses, maintains the analog-to-digital converter. 14 and block 15,

Claims

Claim

A device for detecting a telephone signal according to aut. Sv, No. 965012, characterized in that, in order to improve detection accuracy by eliminating the loss of a useful signal, a clock pulse generator was introduced, connected in series to an analog-to-digital converter, delay unit, digital-to-analog converter, output amplifier and a key whose output is the output of the device for detecting a telephone signal; and the second input is connected to the output of the first element OR, while the first and second inputs of the analog-digital converter are connected respectively to the output of the input amplifier and the first output of the clock, the second output of which is connected to the second input of the delay unit.