SU558412A1 - Device for transmitting pitch speech signal by delta modulation method - Google Patents

Description

one

The invention relates to radio and can be used in synthetic telephony devices and in automatic speech recognition devices.

A device for transmitting a pitch of speech signal by delta modulation methods is known, comprising a delta modulator 1.

However, the known device permits distortion of the pitch of the speech signal.

The aim of the invention is to reduce the distortion of the pitch of a speech signal.

To do this, a delay line, the first and second memory blocks, the inputs of which are fed to the main tone signal, the control unit, the first one-oscillator and the inverter connected in series and the second one-oscillator are inputted to the device for transmitting the speech pitch signal using the delta modulation method The signal "Tone-noise, switches" is given, while the outputs of the delay line of the first and second memory blocks are connected via keys to the control inputs of which are connected to the output of the control unit are connected to the input of the delta modulator, control The first input of the first memory block is connected to the control unit and to the input of the inverter through the first one, and the second one-vibrator output is connected to the control input of the second memory unit, the control unit being sequentially

connected tandem lines, whose input is a Tone-noise signal, and a BAN element, serially connected one-shot and trigger are connected to the input of the delay line, while the one-shot output is connected to the second input of the BANGE element, the output of the delay line is connected to the additional trigger input and the outputs of the delay line, the BAN and the trigger are the outputs of the control unit. The drawing shows a structural electrical: scheme of the proposed device.

A device for transmitting a speech pitch signal by the delta modulation method comprises a delta modulator 1, a delay line 2, the first and second memory blocks 3, 4, the inputs of which are fed to the pitch signal, the control unit 5, the first one-shot 6, in series connected inverter 7 and second

one-shot 8, to the inputs of which a Tone-Noise signal is given, keys 9-11, with the outputs of delay line 2, first and second memory blocks 3 and 4 through keys 9-I, to the control inputs of which the corresponding outputs of the control unit are connected 5 are connected to the input of the delta modulator 1, the control input of the first memory block 3 through the first one-oscillator 6 is connected to the input of the control unit 5 and to the input of the inverter 7, and the output

The second one-shot 8 is connected to the control input of the second memory block 4, while the control block 5 is made in the form of serially connected delay lines 12, at the input of which the signal "Tone-noise, and BAN 13" is connected, to the input of the delay line 12 are connected in series connected one-shot 14 and a trigger 15, while the output of the one-shot 14 is connected to the second input of the prohibitory element 13, the output of the delay line 12 is connected to the auxiliary input of the trigger 15, the outputs of the delay line 12, the prohibitory element 13 and the trigger 15 are block outputs and the control.

The device works as follows.

The pitch signal delayed by the time t With the help of the delay line 2 reaches the delta modulator 1 via a controlled electronic key 9. The control voltage on the key 9 is the signal "Tone noise delayed by the same time t as the pitch signal using delay line 12.

The first memory block 3 stores the first FO value in the voiced speech interval. The control pulse of the memory unit 3 is formed using a single vibrator 6 and corresponds in time to the positive edge of the Tone noise signal. The control voltage of the “resolution delay” is a polar: pulse polarity of duration t, if the duration of the previous unvoiced speech signal interval is equal to or greater than t. If the duration of the previous unvoiced interval is less than t, then the control pulse of key 10 has a duration equal to the duration unvoiced interval. The formation of this control pulse is carried out with the help of a single vibrator 14 and the element BANCH 13. The single vibrator 14 generates pulses of duration t.

The prohibition element 13 is necessary for the formation of a control decision delay voltage applied to the key 10 in cases where the duration of unvoiced speech signal intervals is less than the decision delay time - time t.

The second memory block 4 stores the last FQ value of the voiced speech interval. The control pulse of the memory block 4 is formed using an inverter 7 and a one-shot 8. In time, it corresponds to the negative edge of the Ton-to-Noise signal. To form a control voltage, "tightening the FQ (control voltage on key 11) is triggered 15, which with the arrival of a pulse from the one-oscillator 14 is reset to the initial state corresponding to the opening of key 11. Trigger 15 is shifted to the second steady state with the simultaneous absence of voltage from the delay line 12 and the pulse from the one-shot 14, i.e. only in cases where the duration of the unvoiced

the interval of the speech signal exceeds the time t - the time delay of the decision.

Thus, the original speech pitch signal is pre-processed before being directly fed to the input of the main delta modulator 1. This processing consists, on the one hand, of "tightening FO, i.e., memorizing the last FQ sample on the voiced interval the speech signal and holding the FO value in the memory for a subsequent, unvoiced speech signal interval, on the other hand, in a “time delay for time t, i.e. in storing the first count FO

the subsequent voiced speech interval and its storage in the memory for a period of time t, immediately preceding this counting FQ and located respectively within the previous, unvoiced speech interval, with the " decision delay.

Using the proposed device, it is possible not only abbreviated (on the order of 100 bps)

transmit the pitch signal of fully voiced speech, but also any speech, which increases the scope of the device and eliminates the need to develop such devices.

Claims (2)

1. A device for transmitting pitch-speech signals by the delta modulation method, comprising a delta modulator, characterized in that, in order to reduce the distortion of the pitch-tone signal, a delay line, the first and second memory blocks, are inputted, the pitch signal, the control unit, the first one-shot and the inverter and the second one-shot in series, the inputs of which receive the signal Tone-noise, keys, while the outputs of the delay line, the first and second memory blocks through the keys, to the control inputs which the corresponding outputs of the control unit are connected, connected to the input of the delta modulator, the control input of the first memory block is connected to the input of the control unit and to the input through the first one-oscillator the inverter, and the output of the second one-shot is connected to the control input of the second memory block. 2. The device according to claim 1, characterized in that the control unit is made in the form of serially connected delay lines, to the input of which a signal "Ton-noise, and a BAN element, is supplied, serially connected one-shot and trigger are connected to the input of the delay line, while the output The one-shot is connected to the second input of the BAN, the output of the delay line is connected to the auxiliary input of the trigger, and the outputs of the delay line, the BAN and the trigger are the outputs of the control unit. The source of information taken into account in the examination: 1. S. Gayant "Delta Modulatia of Pitch Formaut and Amplitude Signals for Speech, IEEE, Traus on RD and Electroacousities, 1973, vol AU-21 No. 3 (prototype).