Radio frequency signal AM modulation and signal amplification integrated circuit

Abstract

The utility model provides a radio frequency signal AM modulation and signal amplification integrated circuit. The radio frequency signal AM modulation and signal amplification integrated circuit comprises a carrier signal input end, a to-be-modulated radio frequency signal input end, a modulation amplification output end, a pulse sampling module, a radio frequency tube and an operational amplifier module used for inputting bias voltage to the radio frequency tube. The carrier signal input end is connected with the input end of the radio frequency tube; a to-be-modulated radio frequency signal input end is connected with the pulse sampling module, and the pulse sampling module is connected with an input end of the radio frequency tube through the operational amplifier module. The output end of the radio frequency tube is connected with the modulation amplification output end. The circuit can realize the integration of AM modulation and amplification, saves the volume space, can save the circuit power consumption when the radio frequency signal to be modulated is low in amplitude, and does not need to keep the bias voltage and power consumption under the peak amplitude all the time like a traditional AM modulation amplifier, thereby reducing the average power consumption.

Description

Technical Field

[0001] The utility model relates to the technical field of radio frequency signal modulation and amplification, and more specifically, to an integrated circuit for AM modulation and signal amplification of radio frequency signals. Background Art

[0002] The AM modulation method is a modulation method that makes the carrier signal carry digital signals by changing the amplitude of the carrier signal. Then, to transmit this modulated radio frequency signal, the modulated radio frequency signal needs to be amplified first. The traditional AM modulation signal amplification method is as Figure 1 shown; first, the radio frequency signal to be processed is AM modulated to obtain the modulated radio frequency signal, and then it is input to the grid of the radio frequency tube, and the signal is amplified by the radio frequency tube.

[0003] In order not to distort the modulation signal, the peak power capacity of the traditional AM modulation signal amplification method must be greater than the maximum amplitude after the modulation radio frequency signal is amplified, and the DC load line of the amplification circuit must ensure that the maximum amplitude after the modulation radio frequency signal is amplified can also maintain linearity. Therefore, in the working state, the radio frequency tube requires a very high constant bias voltage, corresponding to a very high static current, and the power consumption also increases accordingly. However, except when the modulation radio frequency signal is at the maximum amplitude and a high static current is required to ensure that the radio frequency tube has sufficient power capacity, such a high static current is not required in other states; therefore, when the modulation radio frequency signal is at a non-maximum amplitude, there is unnecessary power consumption waste in signal amplification. Summary of the Utility Model

[0004] The purpose of the utility model is to overcome the defects and deficiencies in the prior art, and provide an integrated circuit for AM modulation and signal amplification of radio frequency signals; this circuit can realize the integration of AM modulation and amplification, save the volume space, can save the circuit power consumption when the modulation radio frequency signal is at a low amplitude, and does not need to maintain the bias voltage and power consumption at the peak amplitude all the time like the traditional AM modulation amplifier, thereby reducing the average power consumption.

[0005] To achieve the above purpose, the utility model is realized through the following technical solutions: an integrated circuit for AM modulation and signal amplification of radio frequency signals, comprising:

[0006] A carrier signal input terminal for inputting a carrier signal;

[0007] A to-be-modulated radio frequency signal input terminal for inputting a to-be-modulated radio frequency signal;

[0008] A modulation and amplification output terminal for outputting the signal after AM modulation and amplification;

[0009] A pulse sampling module for signal sampling of the time-domain waveform of a radio frequency signal to be modulated by using a sampling pulse signal, so as to obtain an AM time-domain pulse voltage signal whose amplitude varies with the radio frequency signal to be modulated;

[0010] A radio frequency transistor Q1 for signal amplification;

[0011] And an operational amplifier module for inputting a bias voltage to the radio frequency transistor;

[0012] The carrier signal input terminal is connected to the input terminal of the radio frequency transistor; the radio frequency signal input terminal to be modulated is connected to the pulse sampling module, and the pulse sampling module is connected to the input terminal of the radio frequency transistor through the operational amplifier module; the output terminal of the radio frequency transistor is connected to the modulation amplification output terminal.

[0013] Preferably, the operational amplifier module includes an operational amplifier U1; the positive input terminal of the operational amplifier U1 is connected to the pulse sampling module; the negative input terminal of the operational amplifier U1 is connected to the output terminal of the operational amplifier U1, and the output terminal of the operational amplifier U1 is connected to the gate of the radio frequency transistor Q1.

[0014] Preferably, the output terminal of the operational amplifier U1 is grounded through a capacitor C2.

[0015] Preferably, the carrier signal input terminal is connected to the gate of the radio frequency transistor Q1 through a capacitor C1.

[0016] Preferably, the source of the radio frequency transistor Q1 is connected to the power supply VCC1 and is connected to the modulation amplification output terminal; the drain of the radio frequency transistor Q1 is grounded.

[0017] Preferably, the source of the radio frequency transistor Q1 is connected to the modulation amplification output terminal through a capacitor C3.

[0018] Preferably, the source of the radio frequency transistor Q1 is also grounded through a parallel combination of a capacitor C4 and a capacitor C5.

[0019] Preferably, the operational amplifier module is connected to the power supply VCC2.

[0020] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0021] The circuit of the present utility model uses a carrier signal as the input of a radio frequency tube; a pulse sampling module obtains an AM time-domain pulse voltage signal from the radio frequency signal to be modulated. The AM time-domain pulse voltage signal changes with the waveform of the radio frequency signal to be modulated, thereby adjusting the bias voltage of the grid of the radio frequency tube to change the gain of the radio frequency tube, so as to achieve the amplification and change of the amplitude of the carrier signal, and at the same time achieve the AM modulation and signal amplification of the radio frequency signal to be modulated. Integrating AM modulation and amplification not only saves circuit space, but also when the radio frequency signal to be modulated is at a low amplitude, it corresponds to a low bias voltage, low gain and low power consumption of the radio frequency tube; when the radio frequency signal to be modulated is at a high amplitude, it corresponds to a high bias voltage, high gain and high power consumption of the radio frequency tube; the amplitude of the bias voltage can better match the amplitude of the radio frequency signal to be modulated, which can save the circuit power consumption when the radio frequency signal to be modulated is at a low amplitude, and there is no need to keep the bias voltage and power consumption at the peak amplitude all the time like a traditional AM modulation amplifier, thus reducing the average power consumption. Description of the Drawings

[0022] Figure 1 is the structural block diagram of the traditional AM modulation signal amplification method;

[0023] Figure 2 is the circuit schematic diagram of the integrated circuit for AM modulation and signal amplification of the radio frequency signal of the present utility model;

[0024] Figure 3 is the schematic diagram of the principle of the integrated circuit for AM modulation and signal amplification of the radio frequency signal of the present utility model;

[0025] Figure 4 is the traditional AM modulation signal amplification circuit used in the experiment in the embodiment. Detailed Implementation Manner

[0026] The present utility model will be further described in detail below in conjunction with the drawings and the specific implementation manner.

[0027] Embodiment

[0028] An integrated circuit for AM modulation and signal amplification of a radio frequency signal in this embodiment, as Figure 2 shown, includes:

[0029] A carrier signal input terminal for inputting a carrier signal;

[0030] A radio frequency signal to be modulated input terminal for inputting a radio frequency signal to be modulated;

[0031] A modulation and amplification output terminal for outputting the signal after AM modulation and amplification;

[0032] A pulse sampling module for sampling the time-domain waveform of the radio frequency signal to be modulated by using a sampling pulse signal to obtain an AM time-domain pulse voltage signal whose amplitude changes with the radio frequency signal to be modulated;

[0033] RF transistor Q1 for signal amplification;

[0034] and an operational amplifier module for inputting a bias voltage to the RF transistor;

[0035] The carrier signal input terminal is connected to the input terminal of the RF transistor; the RF signal to be modulated input terminal is connected to the pulse sampling module, and the pulse sampling module is connected to the input terminal of the RF transistor through the operational amplifier module; the output terminal of the RF transistor is connected to the modulation amplification output terminal.

[0036] Specifically, the pulse sampling module can adopt the existing technology, and only needs to realize sampling the RF signal to be modulated by using the sampling pulse signal; the frequency of the sampling pulse signal is generally greater than twice the highest frequency of the RF signal to be modulated, and the amplitude of the sampling pulse signal is generally less than 3.3V.

[0037] The operational amplifier module includes an operational amplifier U1; the positive input terminal of the operational amplifier U1 is connected to the pulse sampling module; the negative input terminal of the operational amplifier U1 is connected to the output terminal of the operational amplifier U1, and the output terminal of the operational amplifier U1 is connected to the gate of the RF transistor Q1. The output terminal of the operational amplifier U1 is grounded through a capacitor C2. The operational amplifier U1 is connected to the power supply VCC2.

[0038] The carrier signal input terminal is connected to the gate of the RF transistor Q1 through a capacitor C1. The source of the RF transistor Q1 is connected to the first power supply and is connected to the modulation amplification output terminal through a capacitor C3; the drain of the RF transistor Q1 is grounded. The source of the RF transistor Q1 is also grounded through a parallel-connected capacitor C4 and capacitor C5.

[0039] The frequency of the carrier signal is greater than that of the RF signal to be modulated; the amplitude of the carrier signal generally needs to be greater than the maximum amplitude of the AM-modulated and amplified signal minus the maximum gain of the RF transistor, so that the carrier signal can reach the required maximum signal amplitude after being amplified by the gain of the RF transistor.

[0040] The working principle of the circuit of the present invention is as Figure 3As shown, a carrier signal is used as the input of a radio frequency tube; a pulse sampling module obtains an AM time-domain pulse voltage signal from the radio frequency signal to be modulated. The AM time-domain pulse voltage signal changes with the waveform of the radio frequency signal to be modulated. This processing solution can adopt existing technologies; the AM time-domain pulse voltage signal is input into an operational amplifier module that adjusts the bias voltage of the radio frequency tube, thereby adjusting the gain of the radio frequency tube, changing the amplitude of the carrier signal, and simultaneously realizing the AM modulation and signal amplification of the radio frequency signal to be modulated. Integrating AM modulation and amplification not only saves circuit space, but also when the radio frequency signal to be modulated is at a low amplitude, it corresponds to a low bias voltage, low gain, and low power consumption of the radio frequency tube; when the radio frequency signal to be modulated is at a high amplitude, it corresponds to a high bias voltage, high gain, and high power consumption of the radio frequency tube; the amplitude of the bias voltage can better match the amplitude of the radio frequency signal to be modulated, saving the circuit power consumption when the radio frequency signal to be modulated is at a low amplitude, and not having to maintain the bias voltage and power consumption at the peak amplitude all the time like a traditional AM modulation amplifier, thus reducing the average power consumption.

[0041] To verify the technical effect of reducing the average power consumption, a comparative test was conducted between the circuit of the present invention and a traditional AM modulation signal amplification circuit. The traditional AM modulation signal amplification circuit is as Figure 4 shown, and the results are shown in Table 1.

[0042] Table 1 Comparative Results of Test Power Consumption

[0043] Carrier frequency 220 MHz 240 MHz Output average power 10W 10W Output peak power 40W 40W Average power consumption of traditional circuit 50W 52W Average power consumption of the circuit of the present utility model 47W 50W

[0044] In the AM modulation and amplification test of radio frequency signals with a carrier frequency of 220 MHz and 240 MHz, an output average power of 10 W, and an output peak power of 40 W, the average power consumption of the circuit of the present invention is effectively reduced compared to the average power consumption of the traditional circuit.

[0045] The above embodiments are preferred embodiments of the present invention, but the embodiments of the present invention are not limited to the above embodiments. Any other changes, modifications, substitutions, combinations, and simplifications made without departing from the spirit and principle of the present invention shall be equivalent replacement methods and are all included in the protection scope of the present invention.

Claims

1. An integrated circuit for RF signal AM modulation and signal amplification, characterized in that: Comprising: A carrier signal input terminal for inputting a carrier signal; An RF signal to be modulated input terminal for inputting an RF signal to be modulated; A modulation and amplification output terminal for outputting the AM modulated and amplified signal; A pulse sampling module for sampling the time-domain waveform of the RF signal to be modulated using a sampling pulse signal to obtain an AM time-domain pulse voltage signal whose amplitude varies with the RF signal to be modulated; An RF transistor Q1 for signal amplification; And an operational amplifier module for inputting a bias voltage to the RF transistor; The carrier signal input terminal is connected to the input terminal of the RF transistor; The RF signal to be modulated input terminal is connected to the pulse sampling module, and the pulse sampling module is connected to the input terminal of the RF transistor through the operational amplifier module; the output terminal of the RF transistor is connected to the modulation and amplification output terminal.

2. The integrated circuit for RF signal AM modulation and signal amplification according to claim 1, wherein: The operational amplifier module includes an operational amplifier U1; the positive input terminal of the operational amplifier U1 is connected to the pulse sampling module; the negative input terminal of the operational amplifier U1 is connected to the output terminal of the operational amplifier U1, and the output terminal of the operational amplifier U1 is connected to the gate of the RF transistor Q1.

3. The integrated circuit for RF signal AM modulation and signal amplification according to claim 2, characterized in that: The output terminal of the operational amplifier U1 is grounded through a capacitor C2.

4. The integrated circuit for RF signal AM modulation and signal amplification according to claim 1, characterized in that: The carrier signal input terminal is connected to the gate of the RF transistor Q1 through a capacitor C1.

5. The integrated circuit for RF signal AM modulation and signal amplification according to claim 1, wherein: The source of the RF transistor Q1 is connected to the power supply VCC1 and is connected to the modulation and amplification output terminal; the drain of the RF transistor Q1 is grounded.

6. The integrated circuit for RF signal AM modulation and signal amplification according to claim 5, characterized in that: The source of the RF transistor Q1 is connected to the modulation and amplification output terminal through a capacitor C3.

7. The integrated circuit for RF signal AM modulation and signal amplification according to claim 5, characterized in that: The source of the RF transistor Q1 is also grounded through a parallel combination of a capacitor C4 and a capacitor C5.

8. The integrated circuit for RF signal AM modulation and signal amplification according to claim 1, characterized in that: The operational amplifier module is connected to the power supply VCC2.

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