CN218336006U - Radio reception frequency division control circuit and radio receiver - Google Patents
Radio reception frequency division control circuit and radio receiver Download PDFInfo
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- CN218336006U CN218336006U CN202221879195.8U CN202221879195U CN218336006U CN 218336006 U CN218336006 U CN 218336006U CN 202221879195 U CN202221879195 U CN 202221879195U CN 218336006 U CN218336006 U CN 218336006U
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Abstract
The application provides a radio reception frequency division control circuit and a radio receiver. The radio frequency dividing control circuit comprises an audio controller and a frequency dividing circuit; the frequency dividing circuit comprises a first frequency dividing circuit and a second frequency dividing circuit, the first frequency dividing circuit comprises a first capacitor, a second capacitor, a third capacitor, a first inductor and a second inductor, and the second end of the second capacitor is connected with the frequency modulation input end of the audio controller; the second frequency dividing circuit comprises a fourth capacitor, a fifth capacitor and a third inductor, and the second end of the fifth capacitor is connected with the amplitude modulation input end of the audio controller. Before the antenna signals are input into the audio controller, the first frequency dividing circuit and the second frequency dividing circuit carry out preposed frequency selection on the antenna signals so as to be convenient for inputting the antenna signals with different frequencies into corresponding input ends respectively, thereby reducing the frequency dividing complexity of the audio controller on the antenna signals and further reducing the processing difficulty on the antenna signals.
Description
Technical Field
The utility model relates to a radio technical field especially relates to a radio reception frequency division control circuit and radio.
Background
The radio is mainly used for receiving radio programs of radio stations, the frequency modulation radios in the current market are various, users have great choice and simultaneously put forward higher requirements on the cost performance of the radio, and the radio is easy to carry and has good receiving effect. For the radio with more frequency modulation modes, more wireless signals with better tone quality can be received.
However, in the conventional radio, for the acquisition of different modulation wireless signals, signal processing is basically performed through a built-in DSP chip to obtain corresponding frequency modulation or amplitude modulation signals, which results in that the frequency division degree of the antenna signal depends on the accuracy degree of a built-in program algorithm of the chip, thereby easily resulting in a greater difficulty in processing the antenna signal, and further easily resulting in a poor audio quality of conversion of a part of wireless signals.
SUMMERY OF THE UTILITY MODEL
The utility model aims at overcoming the weak point among the prior art, provide a radio reception frequency division control circuit and radio that effectively reduces the processing degree of difficulty to antenna signal.
The purpose of the utility model is realized through the following technical scheme:
a radio crossover control circuit comprising: the audio frequency controller and the frequency dividing circuit; the audio controller is used for outputting an audio signal; the frequency dividing circuit comprises a first frequency dividing circuit and a second frequency dividing circuit, the first frequency dividing circuit comprises a first capacitor, a second capacitor, a third capacitor, a first inductor and a second inductor, a first end of the first capacitor is used for receiving radio frequency antenna signals, a second end of the first capacitor is connected with a first end of the first inductor, a second end of the first inductor is connected with a first end of the second inductor, a second end of the second inductor is connected with a first end of the second capacitor, a second end of the second capacitor is connected with a frequency modulation input end of the audio controller, a second end of the first inductor is further connected with a first end of the third capacitor, and a second end of the third capacitor is connected with a radio frequency common end; the second frequency dividing circuit comprises a fourth capacitor, a fifth capacitor and a third inductor, wherein the first end of the first capacitor is connected with the first end of the fourth capacitor, the second end of the fourth capacitor is connected with the first end of the third inductor, the second end of the third inductor is connected with the first end of the fifth capacitor, and the second end of the fifth capacitor is connected with the amplitude modulation input end of the audio controller.
In one embodiment, the first frequency-dividing circuit further includes a sixth capacitor, the second terminal of the first inductor is connected to the first terminal of the sixth capacitor, and the second terminal of the sixth capacitor is connected to the first terminal of the second inductor.
In one embodiment, the first frequency-dividing circuit further includes a first resistor, the second terminal of the sixth capacitor is connected to the first terminal of the first resistor, and the second terminal of the first resistor is connected to the second terminal of the third capacitor.
In one embodiment, the first frequency-dividing circuit further includes a fourth inductor, a second terminal of the second inductor is connected to a first terminal of the fourth inductor, and a second terminal of the fourth inductor is connected to a radio frequency common terminal.
In one embodiment, the capacitance value of the first capacitor is greater than the capacitance value of the second capacitor, and the inductance value of the first inductor is greater than the inductance value of the second inductor.
In one embodiment, the second frequency-dividing circuit further includes a second resistor, a second end of the fourth capacitor is connected to a first end of the second resistor, and a second end of the second resistor is connected to the rf common.
In one embodiment, the second frequency-dividing circuit further includes a seventh capacitor and a fifth inductor, a first end of the third inductor is connected to a first end of the seventh capacitor, a second end of the seventh capacitor is connected to a first end of the fifth inductor, and a second end of the fifth inductor is connected to the rf common terminal.
In one embodiment, the second frequency-dividing circuit further includes a sixth inductor, the second terminal of the fourth capacitor is connected to the first terminal of the sixth inductor, and the second terminal of the sixth inductor is connected to the first terminal of the seventh capacitor.
In one embodiment, the radio frequency reception and division control circuit further includes an eighth capacitor, a frequency modulation power supply terminal of the audio controller is used for being connected with an external reference power supply, the frequency modulation power supply terminal of the audio controller is connected with a first terminal of the eighth capacitor, and a second terminal of the eighth capacitor is connected to a radio frequency common terminal.
A radio receiver comprises the radio reception frequency division control circuit in any one of the above embodiments.
Compared with the prior art, the utility model discloses at least, following advantage has:
before the antenna signals are input to the audio controller, the first frequency dividing circuit and the second frequency dividing circuit perform pre-frequency selection processing on the antenna signals, namely, the antenna signals are divided into corresponding frequency modulation signals and amplitude modulation signals, so that the antenna signals with different frequencies are respectively input to corresponding input ends, the frequency division complexity of the audio controller on the antenna signals is reduced, and the processing difficulty of the antenna signals is further reduced.
Drawings
In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings that are required to be used in the embodiments will be briefly described below, it should be understood that the following drawings only illustrate some embodiments of the present invention, and therefore should not be considered as limiting the scope, and for those skilled in the art, other related drawings can be obtained according to the drawings without inventive efforts.
FIG. 1 is a circuit diagram of a radio frequency division control circuit according to an embodiment;
FIG. 2 is a schematic diagram of a first frequency divider circuit in the radio frequency dividing control circuit shown in FIG. 1;
FIG. 3 is a schematic diagram of a second frequency dividing circuit in the sound reception frequency division control circuit shown in FIG. 1;
fig. 4 is a schematic diagram of a circuit board corresponding to the radio reception frequency division control circuit shown in fig. 1.
Detailed Description
In order to facilitate understanding of the present invention, the present invention will be described more fully hereinafter with reference to the accompanying drawings. The preferred embodiments of the present invention are illustrated in the accompanying drawings. The invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete.
It will be understood that when an element is referred to as being "secured to" another element, it can be directly on the other element or intervening elements may also be present. When an element is referred to as being "connected" to another element, it can be directly connected to the other element or intervening elements may also be present. The terms "vertical," "horizontal," "left," "right," and the like as used herein are for illustrative purposes only and do not represent the only embodiments.
Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. The terminology used herein in the description of the invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used herein, the term "and/or" includes any and all combinations of one or more of the associated listed items.
The utility model relates to a radio reception frequency division control circuit. In one embodiment, the sound reception crossover control circuit comprises an audio controller and a crossover circuit. The audio controller is used for outputting audio signals. The frequency dividing circuit comprises a first frequency dividing circuit and a second frequency dividing circuit. The first frequency-dividing circuit comprises a first capacitor, a second capacitor, a third capacitor, a first inductor and a second inductor. The first end of the first capacitor is used for receiving radio frequency antenna signals, the second end of the first capacitor is connected with the first end of the first inductor, the second end of the first inductor is connected with the first end of the second inductor, and the second end of the second inductor is connected with the first end of the second capacitor. The second end of the second capacitor is connected with the frequency modulation input end of the audio controller, the second end of the first inductor is further connected with the first end of the third capacitor, and the second end of the third capacitor is connected to the radio frequency common end. The second frequency dividing circuit comprises a fourth capacitor, a fifth capacitor and a third inductor. The first end of the first capacitor is connected with the first end of the fourth capacitor, the second end of the fourth capacitor is connected with the first end of the third inductor, the second end of the third inductor is connected with the first end of the fifth capacitor, and the second end of the fifth capacitor is connected with the amplitude modulation input end of the audio controller. Before the antenna signals are input to the audio controller, the first frequency dividing circuit and the second frequency dividing circuit perform pre-frequency selection processing on the antenna signals, namely, the antenna signals are divided into corresponding frequency modulation signals and amplitude modulation signals, so that the antenna signals with different frequencies are respectively input to corresponding input ends, the frequency division complexity of the audio controller on the antenna signals is reduced, and the processing difficulty of the antenna signals is further reduced.
Please refer to fig. 1, which is a circuit diagram of a radio reception frequency division control circuit according to an embodiment of the present invention.
The sound reception crossover control circuit 10 of an embodiment includes an audio controller U1 and a crossover circuit 100. The audio controller U1 is configured to output an audio signal. The frequency dividing circuit 100 includes a first frequency dividing circuit 110 and a second frequency dividing circuit 120. Referring to fig. 2, the first frequency-dividing circuit 110 includes a first capacitor C18, a second capacitor C16, a third capacitor C17, a first inductor L10, and a second inductor L3. A first end of the first capacitor C18 is configured to receive a radio frequency antenna signal, a second end of the first capacitor C18 is connected to a first end of the first inductor L10, a second end of the first inductor L10 is connected to a first end of the second inductor L3, and a second end of the second inductor L3 is connected to a first end of the second capacitor C16. The second end of the second capacitor C16 is connected to the frequency modulation input end FM _ IN of the audio controller U1, the second end of the first inductor L10 is further connected to the first end of the third capacitor C17, and the second end of the third capacitor C17 is connected to the radio frequency common end GND _ RF. Referring to fig. 3, the second frequency divider circuit 120 includes a fourth capacitor C20, a fifth capacitor C21, and a third inductor L11. A first end of the first capacitor C18 is connected to a first end of the fourth capacitor C20, a second end of the fourth capacitor C20 is connected to a first end of the third inductor L11, a second end of the third inductor L11 is connected to a first end of the fifth capacitor C21, and a second end of the fifth capacitor C21 is connected to an amplitude modulation input terminal AM _ IN of the audio controller U1.
In this embodiment, before the antenna signal is input to the audio controller U1, the first frequency-dividing circuit 110 and the second frequency-dividing circuit 120 perform pre-frequency-selection processing on the antenna signal, that is, divide the antenna signal into a corresponding frequency modulation signal and an amplitude modulation signal, so as to input the antenna signals with different frequencies to corresponding input terminals, thereby reducing the frequency-dividing complexity of the antenna signal by the audio controller U1, and further reducing the difficulty in processing the antenna signal.
In one embodiment, referring to fig. 2, the first frequency-dividing circuit 110 further includes a sixth capacitor C41, a second end of the first inductor L10 is connected to a first end of the sixth capacitor C41, and a second end of the sixth capacitor C41 is connected to a first end of the second inductor L3. IN this embodiment, the sixth capacitor C41 is connected IN series between the first inductor L10 and the second inductor L3, and the sixth capacitor C41 performs high frequency gating on the signal input by the frequency modulation input end FM _ IN of the audio controller U1, so as to facilitate the frequency selection by embedding the second capacitor C16 and the frequency dividing circuit 100 formed by the second inductor L3, so that the frequency modulation signal input by the frequency modulation input end FM _ IN of the audio controller U1 is more accurate.
Further, referring to fig. 2, the first frequency-dividing circuit 110 further includes a first resistor R8, a second end of the sixth capacitor C41 is connected to a first end of the first resistor R8, and a second end of the first resistor R8 is connected to a second end of the third capacitor C17. IN this embodiment, the first resistor R8 connects the second end of the sixth capacitor C41 to the second end of the third capacitor C17, and the first resistor R8 leads the second end of the sixth capacitor C41 to the radio frequency common terminal GND _ RF, so that the sixth capacitor C41 and the third capacitor C17 are combined to form a new filter capacitor, so as to filter the frequency modulation signal input by the frequency modulation input terminal FM _ IN of the audio controller U1, and thus the frequency modulation signal input by the frequency modulation input terminal FM _ IN of the audio controller U1 is more accurate.
In one embodiment, referring to fig. 2, the first frequency-dividing circuit 110 further includes a fourth inductor L9, a second end of the second inductor L3 is connected to a first end of the fourth inductor L9, and a second end of the fourth inductor L9 is connected to the radio frequency common terminal GND _ RF. IN this embodiment, the first end of the fourth inductor L9 is connected to the second end of the second inductor L3, so that the fourth inductor L9 conducts the frequency-selecting signal flowing through the second inductor L3 at a low frequency, that is, eliminates the low-frequency modulation signal, thereby making the frequency modulation signal input at the frequency modulation input end FM _ IN of the audio controller U1 more accurate.
In one embodiment, the capacitance of the first capacitor C18 is greater than the capacitance of the second capacitor C16, and the inductance of the first inductor L10 is greater than the inductance of the second inductor L3. IN this embodiment, the primary frequency selection circuit formed by the first capacitor C18 and the first inductor L10, and the secondary frequency selection circuit formed by the second capacitor C16 and the second inductor L3 facilitate performing secondary frequency division on the frequency modulation signal, so that the frequency modulation signal input by the frequency modulation input end FM _ IN of the audio controller U1 is more accurate.
In one embodiment, referring to fig. 3, the second frequency-dividing circuit 120 further includes a second resistor R2, a second end of the fourth capacitor C20 is connected to a first end of the second resistor R2, and a second end of the second resistor R2 is connected to the radio frequency common terminal GND _ RF. IN this embodiment, the second resistor R2 is connected IN series with the fourth capacitor C20, and when the sound reception frequency division control circuit does not operate, the fourth capacitor C20 discharges through the second resistor R2, so as to reduce the influence on the amplitude modulation input terminal AM _ IN of the audio controller U1.
In one embodiment, referring to fig. 3, the second frequency-dividing circuit 120 further includes a seventh capacitor C42 and a fifth inductor L26, a first end of the third inductor L11 is connected to a first end of the seventh capacitor C42, a second end of the seventh capacitor C42 is connected to a first end of the fifth inductor L26, and a second end of the fifth inductor L26 is connected to the common radio frequency terminal GND _ RF. IN this embodiment, the seventh capacitor C42 and the fifth inductor L26 form another frequency selection circuit, and different from the frequency selection circuit formed by the fifth capacitor C21 and the third inductor L11, the frequency selection circuit formed by the seventh capacitor C42 and the fifth inductor L26 substantially filters out the amplitude modulation signal with a specified frequency, so that the amplitude modulation signal input by the amplitude modulation input terminal AM _ IN of the audio controller U1 is more accurate.
In one embodiment, referring to fig. 3, the second frequency-dividing circuit 120 further includes a sixth inductor L27, a second terminal of the fourth capacitor C20 is connected to a first terminal of the sixth inductor L27, and a second terminal of the sixth inductor L27 is connected to a first terminal of the seventh capacitor C42. In this embodiment, the sixth inductor L27 is connected in series between the fourth capacitor C20 and the third inductor L11, and the sixth inductor L27 facilitates passing of low-frequency amplitude modulation signals, so as to block passing of amplitude modulation signals with too high frequency, thereby effectively reducing difficulty in processing antenna signals by the audio controller U1.
In one embodiment, referring to fig. 2, the sound reception frequency division control circuit 10 further includes an eighth capacitor C39, the frequency modulation power supply terminal VCC _ FM of the audio controller U1 is configured to be connected to an external reference power supply, the frequency modulation power supply terminal VCC _ FM of the audio controller U1 is connected to a first terminal of the eighth capacitor C39, and a second terminal of the eighth capacitor C39 is connected to the radio frequency common terminal GND _ RF. In this embodiment, the eighth capacitor C39 is used as a stability maintaining capacitor of the radio frequency common terminal GND _ RF, and the eighth capacitor C39 is used for providing a stable reference voltage for the radio frequency common terminal GND _ RF, so that the level of the radio frequency common terminal GND _ RF is stable, and the stability of the frequency division filtering processing on the antenna signal is improved.
In another embodiment, please refer to fig. 4, which is a schematic structural diagram of a circuit board corresponding to a radio reception frequency division control circuit according to an embodiment of the present invention.
In one embodiment, the present application further provides a radio receiver including the radio reception crossover control circuit described in any of the above embodiments. In this embodiment, the sound reception frequency division control circuit includes an audio controller and a frequency division circuit. The audio controller is used for outputting an audio signal. The frequency dividing circuit comprises a first frequency dividing circuit and a second frequency dividing circuit. The first frequency-dividing circuit comprises a first capacitor, a second capacitor, a third capacitor, a first inductor and a second inductor. The first end of the first capacitor is used for receiving radio frequency antenna signals, the second end of the first capacitor is connected with the first end of the first inductor, the second end of the first inductor is connected with the first end of the second inductor, and the second end of the second inductor is connected with the first end of the second capacitor. The second end of the second capacitor is connected with the frequency modulation input end of the audio controller, the second end of the first inductor is further connected with the first end of the third capacitor, and the second end of the third capacitor is connected to the radio frequency common end. The second frequency dividing circuit comprises a fourth capacitor, a fifth capacitor and a third inductor. The first end of the first capacitor is connected with the first end of the fourth capacitor, the second end of the fourth capacitor is connected with the first end of the third inductor, the second end of the third inductor is connected with the first end of the fifth capacitor, and the second end of the fifth capacitor is connected with the amplitude modulation input end of the audio controller. Before the antenna signals are input to the audio controller, the first frequency dividing circuit and the second frequency dividing circuit perform pre-frequency selection processing on the antenna signals, namely, the antenna signals are divided into corresponding frequency modulation signals and amplitude modulation signals, so that the antenna signals with different frequencies are respectively input to corresponding input ends, the frequency division complexity of the audio controller on the antenna signals is reduced, and the processing difficulty of the antenna signals is further reduced.
The above-mentioned embodiments only represent some embodiments of the present invention, and the description thereof is specific and detailed, but not to be construed as limiting the scope of the present invention. It should be noted that, for those skilled in the art, without departing from the concept of the present invention, several variations and modifications can be made, which all fall within the scope of the present invention. Therefore, the protection scope of the present invention should be subject to the appended claims.
Claims (10)
1. A radio crossover control circuit, comprising:
an audio controller for outputting an audio signal;
the frequency dividing circuit comprises a first frequency dividing circuit and a second frequency dividing circuit, the first frequency dividing circuit comprises a first capacitor, a second capacitor, a third capacitor, a first inductor and a second inductor, the first end of the first capacitor is used for receiving radio frequency antenna signals, the second end of the first capacitor is connected with the first end of the first inductor, the second end of the first inductor is connected with the first end of the second inductor, the second end of the second inductor is connected with the first end of the second capacitor, the second end of the second capacitor is connected with the frequency modulation input end of the audio controller, the second end of the first inductor is further connected with the first end of the third capacitor, and the second end of the third capacitor is connected with a radio frequency common end; the second frequency dividing circuit comprises a fourth capacitor, a fifth capacitor and a third inductor, wherein the first end of the first capacitor is connected with the first end of the fourth capacitor, the second end of the fourth capacitor is connected with the first end of the third inductor, the second end of the third inductor is connected with the first end of the fifth capacitor, and the second end of the fifth capacitor is connected with the amplitude modulation input end of the audio controller.
2. The radio frequency division control circuit of claim 1 wherein the first frequency division circuit further comprises a sixth capacitor, the second terminal of the first inductor is connected to the first terminal of the sixth capacitor, and the second terminal of the sixth capacitor is connected to the first terminal of the second inductor.
3. The radio crossover control circuit of claim 2, wherein the first crossover circuit further comprises a first resistor, the second terminal of the sixth capacitor is connected to the first terminal of the first resistor, and the second terminal of the first resistor is connected to the second terminal of the third capacitor.
4. The radio crossover control circuit of claim 1, wherein the first crossover circuit further comprises a fourth inductor, a second terminal of the second inductor is connected to a first terminal of the fourth inductor, and a second terminal of the fourth inductor is connected to a radio frequency common.
5. The radio crossover control circuit of claim 1, wherein the capacitance of the first capacitor is greater than the capacitance of the second capacitor, and the inductance of the first inductor is greater than the inductance of the second inductor.
6. The radio frequency division control circuit of claim 1, wherein the second frequency division circuit further comprises a second resistor, a second end of the fourth capacitor is connected with a first end of the second resistor, and a second end of the second resistor is connected to a radio frequency common terminal.
7. The radio frequency division control circuit of claim 1, wherein the second frequency division circuit further comprises a seventh capacitor and a fifth inductor, a first terminal of the third inductor is connected to a first terminal of the seventh capacitor, a second terminal of the seventh capacitor is connected to a first terminal of the fifth inductor, and a second terminal of the fifth inductor is connected to a radio frequency common terminal.
8. The radio crossover control circuit of claim 7, wherein the second crossover circuit further comprises a sixth inductor, the second terminal of the fourth capacitor is connected to the first terminal of the sixth inductor, and the second terminal of the sixth inductor is connected to the first terminal of the seventh capacitor.
9. The radio frequency reception control circuit according to claim 1, further comprising an eighth capacitor, wherein the frequency modulation power supply terminal of the audio controller is configured to be connected to an external reference power supply, the frequency modulation power supply terminal of the audio controller is connected to a first terminal of the eighth capacitor, and a second terminal of the eighth capacitor is connected to the radio frequency common terminal.
10. A radio receiver comprising the radio reception crossover control circuit of any of claims 1 through 9.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202221879195.8U CN218336006U (en) | 2022-07-20 | 2022-07-20 | Radio reception frequency division control circuit and radio receiver |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202221879195.8U CN218336006U (en) | 2022-07-20 | 2022-07-20 | Radio reception frequency division control circuit and radio receiver |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN218336006U true CN218336006U (en) | 2023-01-17 |
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Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
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| CN202221879195.8U Active CN218336006U (en) | 2022-07-20 | 2022-07-20 | Radio reception frequency division control circuit and radio receiver |
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| Country | Link |
|---|---|
| CN (1) | CN218336006U (en) |
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2022
- 2022-07-20 CN CN202221879195.8U patent/CN218336006U/en active Active
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