SU995350A1 - Device for transmitting emergency signals - Google Patents

Description

The invention relates to communication technology and can be used with; /. alarms from co. Rablay and aircraft.

An external device for transmitting alarms containing serially connected information sources, a modulator, a power amplifier and an antenna, as well as a generator, the triggering input of which is connected to the information source and the output connected to the second input of the modulator Cl.

The disadvantage of this device is that if at the point of reception surface and spatial waves are interesting with a phase shift close to 180 °, then distress signals and accidents are not accepted for any large radiated UT background. At the interference of two harmonic oscillations, the total amplitude at each point in space is determined by the expression

 CD

And UA + L | + cosMgle A and AT - amplitudes of folding waves:

H 4 the phase difference between them at the point in question.

The path of arrival of the second (spatial) wave to the reception point varies irregularly and depends on random factors. Therefore, the interference component of 2A-, A2COsf varies widely and can

10 to be both positive and negative. The amplitude of the resulting wave varies from. At the points where 2Jh is an integer to A-j-Ag at the points where 1 / l (Zri + l). In reality, there are areas where the amplitudes of surface and spatial waves are the same and the resulting amplitude varies randomly from 2 L to zero.

20

The purpose of the invention is to increase the number ... of the alarm.

The goal is achieved by the fact that in the proposed device

25 entered in series with the recorder of the pulse end; sequences, a switch and a unit for smooth variation of the carrier frequency, the output of which is connected to the input

thirty

Claims (1)

control of the master oscillator, and the input of the recorder of the end of the pulse sequences is connected to the recording output of the information source. FIG. 1 shows the structural electrical circuit of the proposed device} in FIG. 2, -. 4 - time diagrams for his work. The device consists of the transmitting | And receiving 2 parts. The transmitting part 1 consists of a switch 3 connected to a telegraph key 4 or in a sub-sampler 5. Recording one; of a telegraph key 4 or an automatic feeder 5 is connected to the input of the recorder b of the I1 termination sequence, which through switch 7 and the unit 8 for smoothly varying the carrier frequency is connected to the master oscillator 9, the output of which is connected via a modulator 10 to the amplifier 11 The 12 V antenna of the receiving part 2 is connected to the antenna 13; the matching unit 14, the mixer 15, the first amplifier 16 via the intermediate frequency (IF amplifier), the second IFC 17, the detector 18 amplifier 19 with the low frequency and the background background 20 are connected to the second input cm CITEL 15 is connected a local oscillator 21 and to a second input of the second IF amplifier 17 - the second output of the modulator 10, The apparatus operates as follows. , Using switch 3, a telegraph key 4 or an automatic feeder 5 is connected. A telegraph key 4 creates Morse code signals, and an automatic feeder 5 generates radio telegraph alarms and distress signals. When transmitting the first series of alarms and distress signals or Morse code signals, the recorder 6 of the pulse sequence using the switch 7 does not turn on the unit 8 of smoothly changing the carrier frequency, the automatic feeder 5 or the Morse code generated by the body graphical 1SA 4, is input to the master oscillator 9 and modulator 10 With the help of the generator 9, oscillations of a constant carrier frequency are generated. When the telegraph key 4 or the contacts of the automatic feeder .5 are closed, these oscillations modulate in amplitude, amplify and radiate ayut antenna 12. The amplitude of the surface (Ardvi) and spatial yell equal (Figure 2). Then according to the formula (1) at А 2 А „о (Fig.2a), at Р 90 А.2b), and at f 180 the signal can not be registered} (Fig. 2c), since its total amplitude approaches zero . After the termination of the first series of alarms and distress or a series of Morse code signals with the aid of the recorders of the end of the pulse sequences and the switch 7, the unit 8 is switched on to smoothly change the carrier frequency. The oscillator 9 generates oscillations, the carrier frequency of which increases or decreases smoothly until the end of the pulse. The modulator 10 modulates these oscillations in amplitude and emits an antenna 12 "At the reception point, the surface and spatial radio waves are received simultaneously and the carrier frequencies of the second series of which are gradually changed. Since spatial radio waves arrive at a reception point with some delay relative to the top of the internal radio waves, they are routed with different frequencies and form a beating (Fig. 3). When two harmonic oscillations are summed, the frequencies of which are somewhat different (Fig. 3a and 3b), beating occurs (Fig. 3 Sv). A change in the phase difference of these oscillations leads to a shift in the maximum and minimum values in the input, but the average signal power, if its duration i, where T beat, is the same for any phase difference at the moment of the beginning of the summation. At different phases of oscillations being recalled (Figs. 4a-4c), the average power of the pulses remains unchanged. Periol oscillations of modulation are made (significantly less than Tj. For example, T «1 ms, t 100–1000 ms. When receiving oscillations of a given frequency band, they select, oscillate these oscillations with oscillations of the local oscillator 21 and amplify at intermediate frequency in blocks (16 and 17). If they receive modulated oscillations, then IFP 17 oscillates from the modulator 10 at the intermediate frequency. Detectors 18 detect the oscillations, amplify at a low frequency, and feed these oscillations to the telephone 20. Thus, the proposed device eliminates cases in which The available emergency radio signals are zero, and also allows the average power of the second series of alarms and distress signals at the input of the receiving devices to be achieved by negligible use of the frequency band, which increases the probability of receiving alarms. information source, a modulator, a power amplifier and an antenna, as well as a master oscillator, the input of which soy is given to the information source, and the stroke is connected to the second modulator input, characterized in that, in order to increase the noise immunity of the transmitted alarms, serially connected recorders of the pulse sequence, a switch and a power carrier frequency change module, whose output is connected to the control input of the master oscillator, are entered into it, and the input of the recorder of the end of the pulse sequences is connected to the recording output of the information source. Sources of information taken into account in the examination 1. A. Kaufman. and Latvijenko P.I., Organizational and emergency means of radio communication in the fleet. M., Pischeva Industrial, 1975, p. 77-93 (prototype). R Fog. f