SU995365A1 - Frequency-modulated signal transmitting device - Google Patents

Description

FIELD: radio engineering. - -,

A device for transmitting frequency modulated screens is known, containing successively soy;: non-synchronous synchronizer, switch, first translate 195th unit, corrector, modulator, signal generator and tunable band-pass filter, synchronous: the output of which is connected to the xhkod synchronizer and sync; | the first input of the switching unit, the second input of which is Connected to the input of the modulator 1J.

However, in a known device it is impossible to obtain a large index.

| 4DULATIONS.

The closest technical solution to the present invention is a device for transmitting signals with frequency modulation, comprising a switch, a pulse shaper: a variable amplifier, the first module. low pass, frequency divider and series-connected controlled oscillator and phase detector 2}

However, in the known device a significant frequency spectrum of transmitted signals.

The purpose of the invention is to narrow the frequency spectrum of the transmitted signals.

To achieve this goal, a device for transmitting signals with frequency modulation, containing a com-; Mutor, pulse shaper, adjustable amplifier, the first low-pass filter ,. A frequency wave and a series-connected controlled oscillator and a phase detector were entered, an adder, a decoder, a second low-pass filter, a pulsed phase detector, a master oscillator, a frequency multiplier and a series were entered.

15 connected differentiating unit, trimming pulse separator and memory unit, the output of which is connected to the input of the first low-pass filter, the output of which is connected to the first input of the adder, to the second input of which the output of the adjustable amplifier is connected, the first input of which is connected to the first input differentiating unit a and with the first output of the mutator, the second output of which is connected to the input of the decoder, the gate of which is connected to the second input of the adjustable amplifier, to the second input of the differentiating unit and to input., pulse shaper, output

which is connected to the first input of a pulsed phase detector, the second input and output of which are connected by the corresponding output frequency divider and to the input of the second low-pass filter whose output is connected to the input of the master oscillator whose outputs are connected to the inputs of the frequency divider and frequency multiplier whose output is connected to the second input of the phase detector, the output of which is connected to the second input of the memory unit, while the output of the adder is connected to the input of the controlled oscillator.

FIG. Figure 1 shows the electrical structure of the device proposed; in fig. 2 - diagrams on the operation of the device.

The device contains a frequency divider 1, low pass filter 2, switch 3, controlled oscillator 20 4, phase detector 5, pulse shaper 6, pulse phase detector .7, low pass filter 8, oscillator 9, frequency multiplier 10 A decoder 11 ,, adjustable amplifier 12, an adder 13, a differentiating unit 14, a trimming pulse extractor 15, a memory block 16.

The device works as follows 30 times.

The modulation of the useful information of the controlled oscillator 4 is carried out by a signal from the switch 3 (Fig. 2C |) through an adjustable amplifier 3S and 12 and the adder 13, the deviation of the output signal being determined by the code signal sent to the control input regul. amplifier 12 from the output of the decoder-Q rarator 11, which selects the required -scale according to the duration of the corresponding clock pulse that arrives at the input of the decoder 11 from the switch output 3 tick SF. 2dr),

The frequency stability of the controlled oscillator 4 is determined by the phase-locked circuit of the PLLHF consisting of the master oscillator 9, the frequency multiplier 10, the phase detector 5, the memory block 16 and the filter 2, and the tuning of the controlled oscillator 4 occurs during the operation of the control oscillator. a pulse arriving at the input of the block 16, a set of 55 lapsing the PLL.

The control pulse is generated by the block 15 according to the information impulse of a certain amplitude and the rhodifferentiated clock pulse from the differentiating unit 14 (Fig. 2-VU, When there is no control pulse, the ring is opened and the memory capacitance remains ignored by the error generated by the number 65)

pom pLL. The frequency multiplier 10 generates generators by a high-frequency signal, not allowing them to synchronize at the moment of opening the PLL. The frequency of the master oscillator 9, in turn, is tuned to the frequency of the clock pulses by the second PLL circuit, consisting of the divider 1 of the frequency of the pulsed phase detector 7, the filter 8 and the driver b.

Thus, the phase of the signal from the output of the switch 3 clock coincides in phase with the signal of the master oscillator 9. Shaper 6 is necessary to generate pulses, to ensure the operation of the pulsed phase detector 7, and also gives the same repetition frequency when changing the tact with the transition to another code that is a multiple of the specified in description.

Thus, the controlled oscillator 4 is essentially adjusted by the PLL circuit by a signal that is a multiple of the clock signal of the switch 3 at the moment of arrival of the control pulse to the memory block 16, which in turn is associated with the clock pulses and the information pulse transmitted (Fig. 2t ). As a result, the combination and side components of the spectrum are completely eliminated, since the phase, oscillations of the master oscillator 9, and the pulse of the control unit 16 of the memory match. Therefore, in the spectrum of nat components that are different from the main components of the spectrum.

In addition, since the capture of the PLL of the controlled oscillator 4 lacks combination and side components, the capture time of such a system is reduced, and the transient process is constant, which reduces the distortion of the transmitted information by the PLL and creates a higher modulation signal: . The use of the decoder 11 and the adjustable amplifier 12 allows to transmit not only two-position, but also other types of codes, which allows to optimize the deviation of the transmitted signal.

Thus, a device for transmitting signals with frequency modulation completely eliminates the combination and side components of the spectrum and, therefore, narrows the spectrum of the transmitted signal and also optimizes the deviation of the transmitted signal with different types of code.

Claims (2)

1. The author's certificate of the USSR 542351, cl. H 04 j 4/00, 1975. 0 2. USSR author's certificate 767999, cl. H 04 L 27/12, 1978 Gprotioty).