An efficient amplitude modulation system and method

Abstract

The present invention provides an efficient amplitude modulation system to solve the problems of poor linearity of the modulation characteristics and low efficiency of the amplitude modulation circuit in the prior art. This efficient amplitude modulation system includes: a buck conversion circuit and an inverse class-E power amplifier circuit, which are electrically connected between the buck conversion circuit and the inverse class-E power amplifier circuit; the buck conversion circuit is used to receive a preset modulation signal, perform conversion on the preset modulation signal, and output a preset modulation conversion signal; the inverse class-E power amplifier circuit is used to receive a square wave signal with the same frequency as the preset carrier wave and the preset modulation conversion signal output by the buck conversion circuit, and output a preset modulated wave signal corresponding to the preset carrier wave signal and the preset conversion signal. The mode of this amplitude modulation system is equivalent to an efficient multiplier. Using this amplitude modulation system, the efficiency is high.

Description

Technical Field

[0001] The present invention relates to the field of amplitude modulation technology, and particularly to an efficient amplitude modulation system and method. Background Art

[0002] Transmitting information is one of the important contents of human life. There are many means of transmitting information. Using radio technology for information transmission occupies a very important position among these means. Radio communication, broadcasting, television, navigation, radar, remote control and telemetry, etc., are all ways of using radio technology to transmit various different information.

[0003] Broadcasting and radio communication use modulation technology to add a low-frequency signal to a high-frequency signal and transmit it. Among them, the low-frequency signal is called the modulation signal, and the high-frequency signal is called the carrier. The common continuous wave modulation methods include amplitude modulation and frequency modulation. Amplitude modulation is to make the amplitude of the carrier signal change with the amplitude of the modulation signal, and the frequency and phase of the carrier remain unchanged. Amplitude modulation is a non-linear frequency conversion process, usually carried out in a class C amplifier stage, realized by the cooperation of non-linear devices such as diodes or triodes and transformers, etc. The circuit mostly works in the under-voltage region or remains in the critical or weakly over-voltage state, and the linearity of the modulation characteristic is poor, the efficiency is low and the circuit implementation is relatively complex. Summary of the Invention

[0004] In order to solve the above problems, the present invention provides an efficient amplitude modulation system and method based on a Buck conversion circuit and an inverse E-class power amplifier circuit.

[0005] In order to achieve the above object, the efficient amplitude modulation system and method adopt the following technical solutions:

[0006] An efficient amplitude modulation system includes: a buck conversion circuit and an inverse E-class power amplifier circuit, and the buck conversion circuit and the inverse E-class power amplifier circuit are electrically connected;

[0007] The buck conversion circuit is used to receive a preset modulation signal, transform the preset modulation signal, and output a preset modulation transformation signal;

[0008] The inverse E-class power amplifier circuit is used to receive a square wave signal with the same frequency as the preset carrier and the preset modulation transformation signal output by the buck conversion circuit, and output a preset modulated wave signal corresponding to the preset carrier signal and the preset transformation signal.

[0009] An efficient amplitude modulation method includes the steps of:

[0010] S1: Receive a preset modulation signal, transform the preset modulation signal through the buck conversion circuit, and output a preset modulation transformation signal;

[0011] S2: Send the square wave signal with the same frequency as the preset carrier wave and the preset modulation transformation signal output by the buck conversion circuit to the inverse class-E power amplifier circuit, and output the preset modulated wave signal corresponding to the preset carrier wave and the preset modulation transformation signal through the inverse class-E power amplifier circuit.

[0012] The beneficial effects of the present invention are as follows:

[0013] (1) The buck conversion circuit and the inverse class-E power amplifier are used for signal conversion, and the circuit conversion efficiency is high.

[0014] (2) The buck conversion circuit can provide energy for the preset modulation signal during the conversion process of the preset modulation signal, increase the energy of the signal and extend the transmission distance. Description of the Drawings

[0015] Figure 1 is the circuit principle of this high-efficiency amplitude modulation system Figure 1 ;

[0016] Figure 2 is the circuit principle of this high-efficiency amplitude modulation system Figure 2 ;

[0017] Figure 3 is the flowchart of this high-efficiency amplitude modulation method. Detailed Embodiments

[0018] The following are specific embodiments of the present invention and in combination with the drawings, the technical solutions of the present invention are further described, but the present invention is not limited to these embodiments.

[0019] Embodiment 1

[0020] This embodiment provides a high-efficiency amplitude modulation system to solve the problems of poor linear modulation characteristics and low efficiency in the prior art using non-linear frequency conversion, as Figures 1 to 2 shown:

[0021] This system includes: a buck conversion circuit and an inverse class-E power amplifier circuit, and the buck conversion circuit and the inverse class-E power amplifier circuit are electrically connected;

[0022] The buck conversion circuit is used to receive the preset modulation signal, perform conversion on the preset modulation signal, and output the preset modulation transformation signal;

[0023] The inverse class-E power amplifier circuit is used to receive the square wave signal with the same frequency as the preset carrier wave and the preset modulation transformation signal output by the buck conversion circuit, and output the preset modulated wave signal corresponding to the preset carrier wave signal and the preset transformation signal.

[0024] As Figure 1As shown, after the preset modulation signal is transformed by the buck conversion circuit, the common-mode value of the preset modulation transformation signal changes relative to the preset modulation signal. The preset modulation transformation signal is used as the input of the inverse class-E power amplifier, and a square-wave signal with the same frequency as the preset carrier is used as the switching input signal of the inverse class-E power amplifier, and a preset modulated wave signal is output through the inverse class-E power amplifier.

[0025] Further, as a preferred implementation manner, the buck conversion circuit provided in this embodiment includes: a PWM circuit or a PFM circuit, an LC filter circuit, as Figure 2 shown, when the preset modulation signal is a sine-wave modulation signal with a preset frequency, the sine-wave modulation signal generates a preset first transformation signal with the same amplitude and different frequencies after being modulated by the PWM circuit of the buck conversion circuit; or the sine-wave modulation signal generates a preset first transformation signal with different amplitudes and the same frequency after being modulated by the PFM circuit of the buck conversion circuit;

[0026] The preset first transformation signal passes through the LC low-pass filter circuit and outputs a sine signal with a different common-mode value from the preset modulation signal, that is, the preset modulation transformation signal.

[0027] The preset modulation transformation signal generated after conversion and the square-wave signal with the same frequency as the preset carrier are respectively used as the signal input signal and the switching signal of the inverse class-E power amplifier, and the amplitude modulation process is completed through the inverse class-E power amplifier, and a preset modulated wave signal is output.

[0028] An efficient amplitude modulation system provided in this embodiment, in which the preset modulation signal is first transformed by the buck circuit, and the common-mode value of the preset modulation transformation signal changes relative to the preset modulation signal; then the inverse class-E power amplification circuit is connected as the load of the buck circuit, and then the square-wave signal with the same frequency as the preset carrier is used as the switching input signal of the inverse class-E power amplification circuit. Ideally, neither the buck conversion circuit nor the inverse class-E power amplifier has energy-consuming components, and the circuit conversion efficiency is as high as 100%, with high efficiency; and the buck conversion circuit can provide energy for the preset modulation signal during the signal conversion process, increasing the energy of the signal and extending the transmission distance.

[0029] Embodiment 2

[0030] This embodiment provides an efficient amplitude modulation method to solve the problems of complex amplitude modulation steps, poor modulation effect, and low amplitude modulation efficiency in the prior art. As Figure 3 shown, this method includes the steps of:

[0031] S1: Receive a preset modulation signal, transform the preset modulation signal through a buck conversion circuit, and output a preset modulation transformation signal;

[0032] S2: Send the square wave signal with the same frequency as the preset carrier wave and the preset modulation transformation signal output by the buck conversion circuit to the inverse class-E power amplifier circuit, and output the preset modulated wave signal corresponding to the preset carrier wave and the preset modulation transformation signal through the inverse class-E power amplifier circuit.

[0033] Further, as a preferred implementation manner, the buck conversion circuit provided in this embodiment includes: a PWM circuit or a PFM circuit, and an LC filter circuit;

[0034] Among them, first, the pulse modulation circuit of the buck conversion circuit performs pulse modulation on the received preset modulation signal and outputs a preset first transformation signal;

[0035] The pulse modulation includes performing pulse width modulation on the preset modulation signal through the PWM circuit of the pulse modulation circuit or performing pulse frequency modulation on the preset modulation signal through the PFM circuit of the pulse modulation circuit; then output a preset first transformation signal with the same amplitude and different frequencies or output a preset first transformation signal with different amplitudes and the same frequency.

[0036] After outputting the preset first transformation signal, perform low-pass filtering on the preset first transformation signal through the LC filter circuit of the buck conversion circuit and output the preset modulation transformation signal.

[0037] Send the square wave signal with the same frequency as the preset carrier wave and the preset modulation transformation signal output by the buck conversion circuit to the inverse class-E power amplifier circuit, and output the preset modulated wave signal corresponding to the preset carrier wave and the preset modulation transformation signal through the inverse class-E power amplifier circuit.

[0038] Adopting this efficient amplitude modulation method, the amplitude modulation efficiency is high.

[0039] The specific embodiments described herein are merely illustrative of the spirit of the present invention. Those skilled in the art of the present invention can make various modifications or supplements to the described specific embodiments or use similar ways to replace them, but will not deviate from the spirit of the present invention or exceed the scope defined by the appended claims.

Claims

1. An efficient amplitude modulation system, characterized in that, Comprising: a buck conversion circuit and an inverse class-E power amplifier circuit, electrically connected between the buck conversion circuit and the inverse class-E power amplifier circuit; the buck conversion circuit is configured to receive a preset modulation signal, perform conversion on the preset modulation signal, and output a preset modulation conversion signal; the inverse class-E power amplifier circuit is configured to receive a square wave signal having the same frequency as the preset carrier wave and the preset modulation conversion signal output by the buck conversion circuit, and output a preset modulated wave signal corresponding to the preset carrier wave signal and the preset conversion signal; the buck conversion circuit includes a PFM circuit and an LC filter circuit; the preset modulation signal is modulated by the PFM circuit to generate a preset first conversion signal having the same amplitude but different frequencies; the preset first conversion signal passes through the LC filter circuit and outputs a preset modulation conversion signal having a different common-mode value from the preset modulation signal; the generated preset modulation conversion signal and the square wave signal having the same frequency as the preset carrier wave are respectively used as the signal input signal and the switch signal of the inverse class-E power amplifier, and the amplitude modulation process is completed through the inverse class-E power amplifier to output a preset modulated wave signal.

2. An efficient amplitude modulation method, characterized in that, Including the steps: S1: Receive a preset modulation signal, perform conversion on the preset modulation signal through the buck conversion circuit, and output a preset modulation conversion signal; the preset modulation signal is modulated by the PFM circuit to generate a preset first conversion signal having the same amplitude but different frequencies; the preset first conversion signal passes through the LC filter circuit and outputs a preset modulation conversion signal having a different common-mode value from the preset modulation signal; S2: Send the square wave signal having the same frequency as the preset carrier wave and the preset modulation conversion signal output by the buck conversion circuit to the inverse class-E power amplifier circuit, and output a preset modulated wave signal corresponding to the preset carrier wave and the preset modulation conversion signal through the inverse class-E power amplifier circuit; the generated preset modulation conversion signal and the square wave signal having the same frequency as the preset carrier wave are respectively used as the signal input signal and the switch signal of the inverse class-E power amplifier, and the amplitude modulation process is completed through the inverse class-E power amplifier to output a preset modulated wave signal.

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