Communication system with strong anti-interference performance

Abstract

The utility model discloses a communication system with strong anti-interference performance, which comprises a transmitting system and a receiving system, the transmitting system comprises a modulator, and the receiving system comprises a demodulator; the transmitting system comprises a crystal oscillator, a first voltage-controlled oscillator, a buffer stage circuit, an amplification stage circuit, a frequency-halving-by-two circuit, a first phase discriminator, a first loop filter and an LPF low-pass filter. The output end of the crystal oscillator is connected with the input end of the first phase discriminator, the output end of the first phase discriminator is connected with the input end of the first loop filter, the output end of the first loop filter is connected with the input end of the first voltage-controlled oscillator, and the output end of the first voltage-controlled oscillator is connected with the input end of the LPF. According to the utility model, the wireless communication effect can be achieved on the basis that the circuit is simple and easy to realize, and the anti-interference effect on external noise can be achieved to a certain extent in short-distance signal transmission.

Description

Technical Field

[0001] The utility model relates to the technical field of communication systems, in particular to a communication system with strong anti-interference performance. Background Art

[0002] Radio communication systems can be used to transmit information from one place to another, and we deal with wireless communications all the time in our daily lives.

[0003] Currently, common communication systems generally have the problem of anti-interference ability of signal transmission. If a communication system with strong anti-interference ability is to be implemented, the circuit will be too complicated. For this reason, we propose a communication system with strong anti-interference ability. Utility Model Content

[0004] The utility model aims to provide a communication system with strong anti-interference performance to solve the problems in the prior art.

[0005] To achieve the above object, the utility model provides the following technical solution: a communication system with strong anti-interference performance, comprising a transmitting system and a receiving system, wherein the transmitting system comprises a modulator, and the receiving system comprises a demodulator;

[0006] The transmitting system comprises a crystal oscillator, a first voltage-controlled oscillator, a buffer stage circuit, an amplifier stage circuit, a divide-by-two frequency circuit, a first phase detector, a first loop filter and an LPF low-pass filter; the output end of the crystal oscillator is connected to the input end of the first phase detector, the output end of the first phase detector is connected to the input end of the first loop filter, the output end of the first loop filter is connected to the input end of the first voltage-controlled oscillator, and the output end of the first voltage-controlled oscillator is connected to the input end of the LPF low-pass filter; the output end of the amplifier stage circuit is connected to the input end of the divide-by-two frequency circuit, and the output end of the divide-by-two frequency circuit is connected to the input end of the first phase detector;

[0007] The receiving system comprises a BPF bandpass filter, a two-stage amplifier circuit, a second phase detector, a second voltage-controlled oscillator, an amplifier circuit, a second loop filter and an audio amplifier circuit; the output end of the BPF bandpass filter is connected to the input end of the two-stage amplifier circuit, the output end of the two-stage amplifier circuit is connected to the input end of the frequency division circuit, the output end of the frequency division circuit is connected to the input end of the second phase detector, the output end of the second phase detector is connected to the input end of the second loop filter, the output end of the second voltage-controlled oscillator is connected to the input end of the amplifier circuit, and the output end of the amplifier circuit is connected to the input end of the second phase detector.

[0008] Preferably, the audio amplifier circuit is a voltage parallel feedback amplifier circuit.

[0009] Compared with the prior art, the beneficial effects of the utility model are:

[0010] The invention can realize the effect of wireless communication on the basis of simple and easy-to-implement circuit, and can realize the effect of anti-interference to external noise to a certain extent in short-distance signal transmission.

[0011] The unique advantage of the transmitting system is that it realizes a high-stability oscillator; the unique advantage of the receiving system is that it can realize high-quality demodulation and amplification of the received signal. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] The accompanying drawings are used to provide a further understanding of the present invention and constitute a part of the specification. Together with the embodiments of the present invention, they are used to explain the present invention and do not constitute a limitation of the present invention. In the accompanying drawings:

[0013] Figure 1 It is the principle diagram of the launch system of the utility model;

[0014] Figure 2 It is the principle diagram of the receiving system of the utility model;

[0015] Figure 3 It is a circuit diagram of the voltage-controlled oscillator of the utility model;

[0016] Figure 4 It is the amplifying circuit diagram in the transmitting system of the utility model;

[0017] Figure 5 It is the circuit diagram of the phase detector of the utility model;

[0018] Figure 6 It is a circuit diagram of the loop filter of the utility model;

[0019] Figure 7 It is a circuit diagram of the bandpass filter of the utility model;

[0020] Figure 8 This is a two-stage amplification circuit diagram of the utility model;

[0021] Fig. 9 The utility model is an audio amplifier circuit diagram. DETAILED DESCRIPTION

[0022] In order to make the purpose, technical scheme and advantages of the embodiments of the utility model clearer, the technical scheme in the embodiments of the utility model will be clearly and completely described below in conjunction with the drawings in the embodiments of the utility model. Obviously, the described embodiments are part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model. Therefore, the following detailed description of the embodiments of the utility model provided in the drawings is not intended to limit the scope of the utility model for which protection is claimed, but merely represents selected embodiments of the utility model.

[0023] See also Figure 1-2 ,In an embodiment of the utility model, a communication system with strong anti-interference performance includes a transmitting system and a receiving system, wherein the transmitting system includes a modulator, and the receiving system includes a demodulator;

[0024] The transmitting system comprises a crystal oscillator, a first voltage-controlled oscillator, a buffer stage circuit, an amplifier stage circuit, a divide-by-two frequency circuit, a first phase detector, a first loop filter and an LPF low-pass filter; the output end of the crystal oscillator is connected to the input end of the first phase detector, the output end of the first phase detector is connected to the input end of the first loop filter, the output end of the first loop filter is connected to the input end of the first voltage-controlled oscillator, and the output end of the first voltage-controlled oscillator is connected to the input end of the LPF low-pass filter; the output end of the amplifier stage circuit is connected to the input end of the divide-by-two frequency circuit, and the output end of the divide-by-two frequency circuit is connected to the input end of the first phase detector;

[0025] The VCO circuit module has the function of frequency modulation and oscillation to generate 36M sinusoidal signals. The main function of the amplifier circuit is to amplify the sine wave modulation signal generated by the voltage-controlled oscillator to drive the frequency division circuit of the subsequent stage. The divide-by-2 frequency divider can divide the amplified sine wave modulation signal by 2 and shape the signal into a square wave. The system uses a high-stability crystal oscillator circuit to generate a reference frequency equal to the frequency of the voltage-controlled oscillator after the frequency division, and sends this signal to the phase detector for phase comparison with the signal of the voltage-controlled oscillator after the frequency division. The phase detector circuit takes out the phase difference between the two input signals and converts the phase difference into the average voltage to control the VCO through a low-pass filter. The loop filter (LF) is a low-pass filter that filters out the high-frequency components and noise in the output of the phase detector and takes out the average component to control the frequency of the voltage-controlled oscillator.

[0026] The receiving system comprises a BPF bandpass filter, a two-stage amplifier circuit, a second phase detector, a second voltage-controlled oscillator, an amplifier circuit, a second loop filter and an audio amplifier circuit; the output end of the BPF bandpass filter is connected to the input end of the two-stage amplifier circuit, the output end of the two-stage amplifier circuit is connected to the input end of the frequency division circuit, the output end of the frequency division circuit is connected to the input end of the second phase detector, the output end of the second phase detector is connected to the input end of the second loop filter, the output end of the second voltage-controlled oscillator is connected to the input end of the amplifier circuit, and the output end of the amplifier circuit is connected to the input end of the second phase detector; the audio amplifier circuit is an amplifier circuit with voltage parallel feedback;

[0027] The main function of the BPF bandpass filter is to pre-select the frequency of the received modulated signal before demodulation, and filter out the unnecessary noise interference for subsequent demodulation. The function of the two-stage amplifier circuit is to amplify the modulated signal after passing through the bandpass filter, so as to facilitate the demodulation work of the subsequent circuit. The phase detector circuit and the VCO oscillator have the same function as in the transmitting system; the audio amplifier circuit is a voltage parallel feedback amplifier circuit, and its main function is to amplify and output the demodulated audio signal so that the audio signal has sufficient energy.

[0028] Finally, it should be noted that the above description is only a preferred embodiment of the utility model and is not intended to limit the utility model. Although the utility model is described in detail with reference to the above embodiments, those skilled in the art can still modify the technical solutions recorded in the above embodiments or replace some of the technical features therein by equivalents. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the utility model shall be included in the protection scope of the utility model.

Claims

1. A communication system with strong anti-interference performance, comprising a transmitting system and a receiving system, characterized in that: The transmitting system includes a modulator, and the receiving system includes a demodulator; The transmitting system comprises a crystal oscillator, a first voltage-controlled oscillator, a buffer stage circuit, an amplifier stage circuit, a divide-by-two frequency circuit, a first phase detector, a first loop filter and an LPF low-pass filter; the output end of the crystal oscillator is connected to the input end of the first phase detector, the output end of the first phase detector is connected to the input end of the first loop filter, the output end of the first loop filter is connected to the input end of the first voltage-controlled oscillator, and the output end of the first voltage-controlled oscillator is connected to the input end of the LPF low-pass filter; the output end of the amplifier stage circuit is connected to the input end of the divide-by-two frequency circuit, and the output end of the divide-by-two frequency circuit is connected to the input end of the first phase detector; The receiving system comprises a BPF bandpass filter, a two-stage amplifier circuit, a second phase detector, a second voltage-controlled oscillator, an amplifier circuit, a second loop filter and an audio amplifier circuit; the output end of the BPF bandpass filter is connected to the input end of the two-stage amplifier circuit, the output end of the two-stage amplifier circuit is connected to the input end of the frequency division circuit, the output end of the frequency division circuit is connected to the input end of the second phase detector, the output end of the second phase detector is connected to the input end of the second loop filter, the output end of the second voltage-controlled oscillator is connected to the input end of the amplifier circuit, and the output end of the amplifier circuit is connected to the input end of the second phase detector.

2. A communication system with strong anti-interference ability according to claim 1, characterized in that: The audio amplifier circuit is a voltage parallel feedback amplifier circuit.

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