SU489144A1 - Device for separating ringtones and speech signals - Google Patents

Description

The invention relates to communication technology.

A device for separating tonal call and speech signals is known, comprising a tone call receiver with an amplitude limiter at the input rf. A band semi-decoder, each spectral K1. Al the synthesizer of which is made in the form of a serially connected filter, amplifier, rectifier and low pass filter.

However, the known device does not provide sufficient protection against false positives, due to the fact that with a large range of ring signal levels from which the receiving device should operate, linear subtraction cannot ensure reliable receiver locking during speech reception.

The aim of the invention is to increase the protection against false alarms when receiving voice signals.

For this, the spectral rectifier

channel with a tone signal

full output and its output is connected to one of the inputs of a tone call receiver, the other input of which is connected to the output of an amplifier of one of the other 5 spectral channels.

The drawing shows the structural electrical circuit of the device, and the diagram does not show the half-decoder analyzer and synthesizer nodes needed 10 to reconstruct the speech spectrum.

A device for separating tonal call and speech signals comprises six spectral channels, the inputs of which are vol; are connected and connected to the input of the device, and each channel contains a series of connected narrow-band receiving filter 1, with the average frequencies of the filters f, j., f, j, j, f g. fg each

20 channels are shifted one relative to the other; go, amplifier 2, two full-wave rectifier 3, low pass filter 4,: the output of each filter 4 is connected to amplifier 5, and its outputs are 25: cut 6 contacts of the executive relay are connected to outputs 7 half a half back and & tonal call receiver 8, consisting of a series-connected amplitude limiter 9, a resonant amplifier 1O, an electronic switch 11, and a winding 12 of the executive relay. One of the inputs of the receiver of the tonal call 8 is connected to the input of a two half-period E Pyrntel 3 of one of the spectral channels, for example, the first one, and the other input of the receiver 8 "with the output of a two-loop rectifier 3 of another spectral channel, ... The device works in a very efficient way. When a call signal on a frequency f arrives at a frequency f, this signal will be pulled out by a narrow-band filter 1 of the fourth channel, amplified by amplifier 2 and nocTpiaeT at the input of a half-period rectifier 3. From the output of rectifier 3 of the fourth channel, a two-phase cycle rectifier will be sent with a double frequency 2fa is set to the input of the amplitude-limiter 9, and at the output of the KOToVioro (for example, rectangular impulses). Amplitude mode limit 9 is selected so that the limit is achieved by changing the input signal level within 20 dB. Due to this, when the ringing signal level B is indicated within the limits, the amplitude of the voltage harmonic, the i-io oscillating circuit tuned to the frequency of the resonant amplifier 10, remains constant and sufficient to trigger the electronic key 11 When the electronic key 11 is triggered, the circuit closes supply winding 12 of the executive relay, the contacts of which 6 are connected to the outputs 7 (towards the subscriber) inductor voltage U 4 When receiving a speech signal to the input of the limiter 9 except for nap. with a frequency of 2 f, a voltage is applied, for example, with a frequency of f. from the output of amplifier 1 of the first channel, which is several times higher than the voltage with a frequency of 2 j. Value Ratio 4, the voltage at the input of the capacitance limiter 9 is determined by the load box. Due to the property of the amplitude limiter 9, to give a weak signal to a stronger one, at the output of the amplitude limiter 9, rectangular pulses will be formed only with the frequency of the protective signal f,. The resonant amplifier circuit 10, tuned to frequency 2 f, attenuates the voltage with frequency J .. and its magnitude is not sufficient to trigger the electronic key 11. Thus, the output of the device will be a signal passing through the first spectral channel, taken from the amplifier output 5. The subject matter of the invention is a device for separating tonal call and speech signals, comprising a tone call receiver with amplitudes Nm at the input limiter and a band half-coder, each spectral channel of which is made in A filter connected in series, an amplifier, a rectifier and a low-pass filter, characterized in that, in order to increase protection against false alarms when receiving speech signals, the rectifier of the spectral channel with the tone signal is executed, D) full-wave and its output is connected to one of the the inputs of the receiver tonal call, the other input of which is connected to the output of the amplifier of one of the other spectral channels.