A resonant hybrid circuit

Abstract

The utility model discloses a resonant hybrid circuit, including the frequency selection unit for carrying out tripler selection to the signal of input, the class C amplifier for the signal of the frequency selection unit output amplification and the buffer amplifier for the signal of class C amplifier output buffer amplification, the frequency selection unit, class C amplifier and buffer amplifier connect in proper order gradually, the utility model discloses an advantage at: carry out tripler selection to the signal of input and then amplify gradually, avoid signal frequency too low, guarantee signal can be received by receiver.

Description

Technical Field

[0001] This utility model relates to the field of wireless transmission communication, and more specifically to a resonant hybrid circuit. Background Technology

[0002] A transmitter is a device that transmits signals at a specific frequency; it's a broad concept widely used in various civilian and military equipment, including television, radio, communications, alarms, radar, remote control, telemetry, and electronic warfare. Transmitters can be categorized into four main types based on their modulation method: frequency modulation (FM), amplitude modulation (AM), phase modulation (PM), and pulse modulation. These can also be analog or digital. Typically, a transmitter consists of three parts: a high-frequency section, a low-frequency section, and a power supply section. The high-frequency section generally includes a main oscillator, a buffer amplifier, a frequency multiplier, intermediate amplifiers, a power amplifier driver stage, and a final power amplifier stage. The main oscillator generates a stable carrier wave. To improve frequency stability, a quartz crystal oscillator is often used in the main oscillator stage, followed by a buffer stage to reduce the impact of subsequent stages on the main oscillator. The low-frequency section includes a microphone, a low-frequency voltage amplifier stage, a low-frequency power amplifier stage, and a final low-frequency power amplifier stage. The low-frequency signal is gradually amplified to obtain the required power level at the final power amplifier stage, enabling modulation of the high-frequency final power amplifier stage. Therefore, the final low-frequency power amplifier stage is also called a modulator. Modulation is the process of loading the information to be transmitted onto a high-frequency oscillation (carrier frequency) signal. Therefore, the final high-frequency power amplifier stage is called a modulated amplifier.

[0003] In a voice transmission wireless transceiver system, the transmitter plays a crucial role. The signal emitted by the transmitter is directly received, processed, and output by the receiver. Therefore, the frequency of the signal during the transmitter transmission process has specific requirements depending on the type of antenna. If the signal frequency is too low during transmission, it will not be received by the receiver. Therefore, it is very important to select the frequency and amplify the signal during the transmitter transmission process. Thus, it is necessary to design a circuit that can select the frequency of the input signal and amplify it step by step. Utility Model Content

[0004] The technical problem to be solved by this utility model is to provide a resonant hybrid circuit that amplifies the input signal step by step after frequency multiplication to avoid the signal frequency being too low and to ensure that the signal can be received by the receiver.

[0005] This utility model solves the above-mentioned technical problems through the following technical means: a resonant hybrid circuit, including a frequency selection unit for selecting the third harmonic of the input signal, a Class C amplifier for amplifying the signal output by the frequency selection unit, and a buffer amplifier for buffering and amplifying the signal output by the Class C amplifier, wherein the frequency selection unit, the Class C amplifier, and the buffer amplifier are connected in sequence.

[0006] This invention designs a frequency selection unit for selecting the input signal by a third harmonic, a Class C amplifier for amplifying the signal output from the frequency selection unit, and a buffer amplifier for buffering the signal output from the Class C amplifier. It can amplify the input signal step by step after selecting the frequency by a third harmonic, avoiding the signal frequency from being too low and ensuring that the signal can be received by the receiver.

[0007] Furthermore, the frequency selection unit includes resistor R6, resistor R14, capacitor C15, transistor VT1, capacitor C4, resistor R15, capacitor C20, inductor L1, and capacitor C12. One end of resistor R6, one end of resistor R14, one end of capacitor C15, and the base of transistor VT1 are connected and connected to the other end of crystal oscillator JT1. The collector of transistor VT1, one end of capacitor C4, one end of inductor L1, and one end of capacitor C12 are connected. The emitter of transistor VT1, the other end of capacitor C15, one end of resistor R15, and one end of capacitor C20 are connected. The other ends of resistor R6, capacitor C4, and inductor L1 are connected and serve as signal input terminals. The other ends of resistor R14, resistor R15, and capacitor C20 are all connected to the anode of diode VD1.

[0008] Furthermore, the Class C amplifier includes resistor R7, resistor R16, capacitor C21, transistor VT2, capacitor C5, inductor L2, and capacitor C7. The other end of capacitor C12, one end of resistor R7, one end of resistor R16, one end of capacitor C21, and the base of transistor VT2 are connected. The collector of transistor VT2, one end of capacitor C5, one end of inductor L2, and one end of capacitor C7 are connected. The other ends of resistor R7, capacitor C5, and inductor L2 are all connected to the other end of inductor L1. The other ends of resistor R16, capacitor C21, and the emitter of transistor VT1 are all connected to the other end of capacitor C20.

[0009] Furthermore, the buffer amplifier includes a resistor R17, a capacitor C22, a transistor VT3, and an inductor L3. The other end of the capacitor C7, one end of the resistor R17, one end of the capacitor C22, and the base of the transistor VT3 are connected. The collector of the transistor VT3 is connected to one end of the inductor L3. The other end of the inductor L3 is connected to the other end of the inductor L2. The other end of the resistor R17, the other end of the capacitor C22, and the emitter of the transistor VT3 are all connected to the emitter of the transistor VT2. The other end of the inductor L3 and the collector of the transistor VT3 are connected and serve as the signal output terminal.

[0010] Furthermore, the buffer amplifier is followed by an impedance-matched transmitter circuit for filtering the signal output from the signal output terminal.

[0011] Furthermore, the impedance matching transmission circuit includes a π-type filter, a resistor R8, an indicator LED1, capacitors C10 and C11, and an antenna E1. The π-type filter includes capacitors C8, C9, C16, C17, C18, and C19, inductors L4, L5, and L6. One end of capacitor C8 is connected to one end of inductor L3, and the other end of capacitor C8, one end of inductor L4, and one end of capacitor C16 are connected together. The other end of inductor L4 is connected to one end of capacitor C9, and the other end of capacitor C9, one end of inductor L5, and... One end of capacitor C17 is connected to the other end of inductor L5, one end of inductor L6, and one end of capacitor C18. The other end of inductor L6, antenna E1, and one end of capacitor C19 are connected to the other end of inductor L3 and connected to the +6V power supply. The other end of resistor R8 is connected to the anode of indicator LED1. The emitter of transistor VT3, the other ends of capacitors C16 to C19, the cathode of indicator LED1, the negative terminal of capacitor C10, and the other end of capacitor C11 are all connected to and grounded.

[0012] The advantages of this utility model are:

[0013] (1) This utility model designs a frequency selection unit for selecting the input signal by a third harmonic, a Class C amplifier for amplifying the signal output by the frequency selection unit, and a buffer amplifier for buffering the signal output by the Class C amplifier. It can amplify the input signal step by step after selecting the frequency by a third harmonic to avoid the signal frequency being too low and ensure that the signal can be received by the receiver.

[0014] (2) In this utility model, transistor VT1 and capacitor C4 select the third frequency, transistor VT2 and capacitor C5 form a class C amplifier to amplify the signal, and transistor VT3 and inductor L3 form a buffer amplifier circuit to buffer and amplify the signal.

[0015] (3) The impedance matching transmitting circuit of this utility model filters out small signal interference through step-by-step filtering. The Π-type impedance matching network minimizes the input impedance so that the antenna can obtain the maximum output power and greatly reduce the antenna radiation loss. Attached Figure Description

[0016] Figure 1 This is a structural block diagram of the voice signal transmitter circuit disclosed in the embodiments of this utility model;

[0017] Figure 2 This is a schematic diagram of the low-frequency amplifier circuit in the voice signal transmitter circuit disclosed in the embodiments of this utility model;

[0018] Figure 3 This is a schematic diagram of the frequency synthesis oscillation circuit in the voice signal transmitter circuit disclosed in the embodiments of this utility model;

[0019] Figure 4 This is a schematic diagram of the resonant hybrid circuit disclosed in the embodiments of this utility model;

[0020] Figure 5 This is a schematic diagram of the impedance matching transmitter circuit in the resonant hybrid circuit disclosed in the embodiment of this utility model. Detailed Implementation

[0021] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly and completely described below in conjunction with the embodiments of this utility model. Obviously, the described embodiments are only some embodiments of this utility model, not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this utility model.

[0022] like Figure 1 As shown, the resonant hybrid circuit 3 provided by this utility model is applied in the voice signal transmitter circuit to perform triple frequency selection and amplification processing on the signal. The voice signal transmitter circuit includes a low-frequency amplifier circuit 1, a frequency synthesis oscillation circuit 2, a resonant hybrid circuit 3, and an impedance matching transmitter circuit 4 connected in sequence. The low-frequency amplifier circuit 1 receives the voice input signal, and the impedance matching transmitter circuit 4 outputs a high-frequency small signal that satisfies the radiation frequency of the internal antenna of the transmitter.

[0023] like Figure 2As shown, the low-frequency amplifier circuit 1 includes capacitors C1, C2, and C3; resistors R1 to R4 numbered sequentially; microphone MK1; resistors R9, R10, and R12; capacitors C13, C14, and C6; transistor VT4; and transistor VT5. Microphone MK1 receives two amplitude-modulated dual-channel voice input signals. The front end of microphone MK1 can be connected to a 30kHz amplitude modulation circuit and a 40kHz amplitude modulation circuit. The amplitude-modulated dual-channel voice signals are then transmitted to the low-frequency amplifier circuit 1 through microphone MK1. One end of microphone MK1 is connected to one end of capacitor C13 and one end of resistor R1. The other end of capacitor C13 is connected to one end of resistor R9 and the base of transistor VT4. The other end of resistor R9 and one end of resistor R2... The collector of transistor VT4 is connected to one end of capacitor C14. The other end of capacitor C14 is connected to one end of resistor R10 and the base of transistor VT5. The other end of resistor R10, one end of resistor R3, the positive terminal of capacitor C6, and the collector of transistor VT5 are connected. The negative terminal of capacitor C6 is connected to frequency synthesis oscillation circuit 2. One end of resistor R12, the emitter of transistor VT5, the emitter of transistor VT4, and the other end of microphone MK1 are connected and grounded. The other end of resistor R12 is connected to one end of resistor R4. Resistors R1 to the other end of resistor R4, the positive terminals of capacitors C1 and C2, and one end of capacitor C3 are all connected. One end of capacitor C3 is connected to resonant mixing circuit 3. The negative terminals of capacitors C1 and C2, and the other end of capacitor C3 are grounded. Transistors VT4 and VT5 amplify the input voice signal in two stages. Resistors and capacitors form a filtering circuit to ensure the stability of signal transmission and filter out signal interference.

[0024] like Figure 3 As shown, the frequency synthesis oscillation circuit 2 includes a resistor R11, a crystal oscillator JT1, and a diode VD1. One end of the resistor R11 is connected to the negative terminal of the capacitor C6, and the other end of the resistor R11 is connected to one end of the crystal oscillator JT1 and the cathode of the diode VD1. The other end of the crystal oscillator JT1 and the anode of the diode VD1 are both connected to the resonant hybrid circuit 3. The frequency of the crystal oscillator JT1 is one-third of 48.5MHz. The frequency synthesis oscillation circuit 2 modulates two different frequencies and applies them to the dual-channel voice input signals to increase the frequency of the voice signals and facilitate signal transmission.

[0025] like Figure 4As shown, the resonant hybrid circuit 3 includes resistor R6, capacitor C4, inductor L1, resistor R7, capacitor C5, inductor L2, capacitor C7, inductor L3, transistors VT1 to VT3 numbered sequentially, capacitor C12, capacitor C15, resistors R14 to R17 numbered sequentially, capacitor C20, capacitor C21, and capacitor C22. One end of resistor R6, one end of resistor R14, one end of capacitor C15, and the base of transistor VT1 are connected and connected to the other end of crystal oscillator JT1. The collector of transistor VT1, one end of capacitor C4, one end of inductor L1, and one end of capacitor C12 are connected. The emitter of transistor VT1, the other end of capacitor C15, one end of resistor R15, and one end of capacitor C20 are connected. The other end of capacitor C12, one end of resistor R7, one end of resistor R16, and capacitor C22 are connected. One end of 21 is connected to the base of transistor VT2; the collector of transistor VT2, one end of capacitor C5, one end of inductor L2, and one end of capacitor C7 are connected; the other end of capacitor C7, one end of resistor R17, one end of capacitor C22, and the base of transistor VT3 are connected; the collector of transistor VT3 is connected to one end of inductor L3; the other ends of resistor R14, resistor R17, capacitor C20, capacitor C21, capacitor C22, and the emitter of transistor VT3 are all connected together; the other ends of resistor R6, capacitor C4, inductor L1, resistor R7, capacitor C5, inductor L2, and inductor L3 are all connected together; the other end of inductor L3 and the emitter of transistor VT3 are connected to impedance matching emitter circuit 4. Transistor VT1 and capacitor C4 form a frequency multiplier circuit to select the third frequency of the resonant hybrid circuit 3. Transistor VT2 and capacitor C5 form a class C amplifier for power amplification. Transistor VT3 and inductor L3 form a buffer amplifier circuit to further buffer and amplify the signal. In this way, the signal after step-by-step amplification can meet the radiation frequency of the antenna, so that the antenna E2 of the receiving part can receive the signal transmitted by the transmitting part. Without signal amplification, the signal is too weak. In addition, there is a certain distance between the transmitting part and the receiving part during transmission, which can easily make it difficult for the receiving part to receive the voice signal.

[0026] like Figure 5As shown, the impedance matching transmitting circuit 4 includes capacitors C8 to C11 (numbered sequentially), inductors L4, L5, and L6, resistor R8, capacitors C16 to C19 (numbered sequentially), indicator LED1, and antenna E1. One end of capacitor C8 is connected to one end of inductor L3, and the other end of capacitor C8, one end of inductor L4, and one end of capacitor C16 are connected. The other end of inductor L4 is connected to one end of capacitor C9, and the other end of capacitor C9, one end of inductor L5, and one end of capacitor C17 are connected. Inductor L5... The other end of the inductor is connected to one end of the inductor L6 and one end of the capacitor C18. The other end of the inductor L6 is connected to the antenna E1 and one end of the capacitor C19. One end of the resistor R8, the positive terminal of the capacitor C10, and one end of the capacitor C11 are all connected to the other end of the inductor L3 and connected to the +6V power supply. The other end of the resistor R8 is connected to the anode of the indicator LED1. The emitter of the transistor VT3, the other ends of capacitors C16 to C19, the cathode of the indicator LED1, the negative terminal of capacitor C10, and the other end of capacitor C11 are all connected to and grounded. The impedance matching transmitter circuit 4 filters out small signal interference through step-by-step filtering. The Π-type impedance matching network minimizes the input impedance, so that the antenna can obtain the maximum output power and greatly reduce the antenna radiation loss.

[0027] Through the above technical solutions, this utility model designs a frequency selection unit for selecting the input signal by a third harmonic, a Class C amplifier for amplifying the signal output by the frequency selection unit, and a buffer amplifier for buffering and amplifying the signal output by the Class C amplifier. It can amplify the input signal step by step after selecting the frequency by a third harmonic, avoid the signal frequency being too low, and ensure that the signal can be received by the receiver.

[0028] The above embodiments are only used to illustrate the technical solutions of this utility model, and are not intended to limit it. Although this utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this utility model.

Claims

1. A resonant hybrid circuit, characterized by, The frequency selection unit, the Class C amplifier and the buffer amplifier are connected in sequence.

2. A resonant hybrid circuit according to claim 1, characterized in that The frequency selection unit comprises a resistor R6, a resistor R14, a capacitor C15, a triode VT1, a capacitor C4, a resistor R15, a capacitor C20, an inductor L1 and a capacitor C12, one end of the resistor R6, one end of the resistor R14, one end of the capacitor C15 and the base of the triode VT1 are connected and connected with the other end of the crystal oscillator JT1; the collector of the triode VT1, one end of the capacitor C4, one end of the inductor L1 and one end of the capacitor C12 are connected, the emitter of the triode VT1, the other end of the capacitor C15, one end of the resistor R15 and one end of the capacitor C20 are connected; the other end of the resistor R6, the other end of the capacitor C4 and the other end of the inductor L1 are connected and serve as a signal input end, the other end of the resistor R14, the other end of the resistor R15 and the other end of the capacitor C20 are connected with the anode of the diode VD1.

3. A resonant hybrid circuit according to claim 2, characterized in that The Class C amplifier comprises a resistor R7, a resistor R16, a capacitor C21, a triode VT2, a capacitor C5, an inductor L2 and a capacitor C7, the other end of the capacitor C12, one end of the resistor R7, one end of the resistor R16, one end of the capacitor C21 and the base of the triode VT2 are connected; the collector of the triode VT2, one end of the capacitor C5, one end of the inductor L2 and one end of the capacitor C7 are connected, the other end of the resistor R7, the other end of the capacitor C5 and the other end of the inductor L2 are connected with the other end of the inductor L1, the other end of the resistor R16, the other end of the capacitor C21 and the emitter of the triode VT1 are connected with the other end of the capacitor C20.

4. A resonant hybrid circuit according to claim 3, characterized in that The buffer amplifier comprises a resistor R17, a capacitor C22, a triode VT3 and an inductor L3, the other end of the capacitor C7, one end of the resistor R17, one end of the capacitor C22 and the base of the triode VT3 are connected; the collector of the triode VT3 is connected with one end of the inductor L3; the other end of the inductor L3 is connected with the other end of the inductor L2, the other end of the resistor R17, the other end of the capacitor C22 and the emitter of the triode VT3 are connected with the emitter of the triode VT2, the other end of the inductor L3 and the collector of the triode VT3 are connected and serve as a signal output end.

5. A resonant hybrid circuit according to claim 4, characterized in that The buffer amplifier is further connected with an impedance matching transmitting circuit for filtering the signal outputted from the signal output end.

6. A resonant hybrid circuit according to claim 5, characterized in that The impedance matching transmitting circuit comprises a pi filter, a resistor R8, a display lamp LED1, a capacitor C10, a capacitor C11 and an antenna E1, the pi filter comprises a capacitor C8, a capacitor C9, a capacitor C16, a capacitor C17, a capacitor C18, a capacitor C19, an inductor L4, an inductor L5 and an inductor L6, one end of the capacitor C8 is connected with one end of the inductor L3, the other end of the capacitor C8, one end of the inductor L4 and one end of the capacitor C16 are connected, the other end of the inductor L4 is connected with one end of the capacitor C9, the other end of the capacitor C9, one end of the inductor L5 and one end of the capacitor C17 are connected, the other end of the inductor L5, one end of the inductor L6 and one end of the capacitor C18 are connected, the other end of the inductor L6, the antenna E1 and one end of the capacitor C19 are connected, one end of the resistor R8, the positive pole of the capacitor C10 and one end of the capacitor C11 are all connected with the other end of the inductor L3 and connected with a power supply +6V, the other end of the resistor R8 is connected with the anode of the display lamp LED1, the emitter of the triode VT3, the other end of the capacitor C16 to the other end of the capacitor C19, the cathode of the display lamp LED1, the negative pole of the capacitor C10 and the other end of the capacitor C11 are all connected and grounded.

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