一种射频检波电路及射频电路
By combining envelope detection circuit, filter circuit and signal amplification circuit, the high-frequency instantaneous voltage spikes of OFDM RF signals are filtered out, the problem of nonlinear operating region of diode envelope detection circuit is solved, and higher precision RF power monitoring and control is achieved.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- IFLYTEK CO LTD
- Filing Date
- 2025-08-11
- Publication Date
- 2026-07-17
AI Technical Summary
The high peak-to-average power ratio of OFDM RF signals causes the diode envelope detector circuit to enter the nonlinear operating region, generating high-frequency instantaneous voltage spikes, which affects the accuracy of RF power monitoring and power control.
By employing a combination of envelope detector circuit, first filter circuit, signal amplification circuit, and second filter circuit, high-frequency instantaneous voltage spikes are filtered out and signal accuracy is improved through signal filtering and amplification.
This improves the accuracy of OFDM RF signal power detection, enabling higher precision RF power monitoring and power control.
Smart Images
Figure CN224521030U_ABST
Abstract
Claims
1. A radio frequency detection circuit, characterized by, include: Envelope detection circuit, the input terminal receives radio frequency signals; The first filtering circuit has its input terminal connected to the output terminal of the envelope detector circuit, and filters the output signal output from the output terminal of the envelope detector circuit. The signal amplification circuit has its input terminal connected to the output terminal of the first filter circuit, and amplifies the output signal output from the output terminal of the first filter circuit. as well as The second filtering circuit has its input terminal connected to the output terminal of the signal amplification circuit, and filters the amplified output signal.
2. The radio frequency detection circuit of claim 1, wherein, The second filtering circuit includes a first voltage divider circuit, a second voltage divider circuit, and a first operational amplifier. One end of the first voltage divider circuit and one end of the second voltage divider circuit are respectively connected to the output terminal of the signal amplification circuit. The other end of the first voltage divider circuit is connected to the non-inverting input terminal of the first operational amplifier, and the other end of the second voltage divider circuit is connected to the inverting input terminal of the first operational amplifier. The output terminal of the first operational amplifier is used as the output terminal of the second filtering circuit.
3. The radio frequency detection circuit of claim 2, wherein, The first voltage divider circuit includes a first resistor, and the second voltage divider circuit includes a first capacitor and a second resistor connected in series. Wherein, one end of the first resistor is connected to the output terminal of the signal amplification circuit, and the other end of the first resistor is connected to the non-inverting input terminal of the first operational amplifier; One end of the first capacitor is connected to the output terminal of the signal amplification circuit, the other end of the first capacitor is connected to one end of the second resistor, and the other end of the second resistor is connected to the inverting input terminal of the first operational amplifier.
4. The radio frequency detection circuit of claim 3, wherein, The second filter circuit also includes a second capacitor and a third resistor. One end of the third resistor is connected to the other end of the first resistor and the non-inverting input of the first operational amplifier, and the other end of the third resistor is connected to one end of the second capacitor, the other end of the second capacitor being grounded.
5. The radio frequency detection circuit of claim 3, wherein, The second filter circuit also includes a third capacitor, a fourth resistor, and a fifth resistor. Wherein, one end of the fourth resistor is connected to the other end of the second resistor and the inverting input terminal of the first operational amplifier, and the other end of the fourth resistor is connected to the output terminal of the first operational amplifier and one end of the fifth resistor. One end of the third capacitor is connected to one end of the fourth resistor, and the other end of the third capacitor is connected to the other end of the fourth resistor; The output terminal of the first operational amplifier is used as the output terminal of the second filter circuit via the fifth resistor.
6. The radio frequency detection circuit of claim 1, wherein, The signal amplification circuit includes a fourth capacitor, a fifth capacitor, a sixth resistor, a seventh resistor, an eighth resistor, a ninth resistor, and a second operational amplifier. Wherein, one end of the sixth resistor is connected to the output terminal of the first filter circuit, and the other end of the sixth resistor is connected to the non-inverting input terminal of the second operational amplifier; One end of the fourth capacitor is connected to the other end of the sixth resistor and one end of the seventh resistor, respectively, and the other end of the fourth capacitor is grounded; One end of the seventh resistor is connected to one end of the fourth capacitor and the non-inverting input of the second operational amplifier, and the other end of the seventh resistor is grounded. One end of the eighth resistor is connected to one end of the ninth resistor and the inverting input terminal of the second operational amplifier, the other end of the eighth resistor is connected to the output terminal of the second operational amplifier, and the other end of the ninth resistor is grounded. One end of the fifth capacitor is connected to one end of the eighth resistor and one end of the ninth resistor, respectively, and the other end of the fifth capacitor is connected to the other end of the eighth resistor; The output terminal of the second operational amplifier is used as the input terminal of the signal amplification circuit.
7. The radio frequency detection circuit of any one of claims 1 to 6, wherein, The envelope detection circuit includes a first diode and a second diode, and the first filter circuit includes a sixth capacitor and a tenth resistor. Wherein, one end of the first diode is used as the input terminal of the envelope detection circuit to receive the radio frequency signal, one end of the first diode is connected to one end of the second diode, the other end of the first diode is connected to the input terminal of the first filter circuit, and the other end of the second diode is grounded; Wherein, one end of the sixth capacitor is used as the input terminal of the first filter circuit, one end of the sixth capacitor is connected to one end of the tenth resistor, the other end of the sixth capacitor is grounded, one end of the tenth resistor is used as the output terminal of the first filter circuit, and the other end of the tenth resistor is grounded.
8. A radio frequency circuit, characterized by include: A power control circuit and / or a power function circuit, and a radio frequency detection circuit as described in any one of claims 1 to 7, wherein the power control circuit and / or the power function circuit is connected to the radio frequency detection circuit.
9. The radio frequency circuit of claim 8, wherein, The power control circuit includes a seventh capacitor, an eighth capacitor, a ninth capacitor, a tenth capacitor, an eleventh resistor, a twelfth resistor, a thirteenth resistor, a third operational amplifier, and a first variable resistor. Wherein, one end of the eleventh resistor is connected to the output terminal of the radio frequency detection circuit, and the other end of the eleventh resistor is connected to the inverting input terminal of the third operational amplifier; One end of the twelfth resistor is connected to the other end of the eleventh resistor and the inverting input terminal of the third operational amplifier, the other end of the twelfth resistor is connected to the first output terminal of the third operational amplifier, one end of the seventh capacitor is connected to one end of the twelfth resistor, and the other end of the seventh capacitor is connected to the other end of the twelfth resistor. The first end of the first variable resistor is connected to the non-inverting input of the third operational amplifier, the second end of the first variable resistor is connected to one end of the eighth capacitor, the third end of the first variable resistor is grounded, and the other end of the eighth capacitor is grounded. One end of the thirteenth resistor is connected to the first end of the first variable resistor and one end of the ninth capacitor, and the other end of the thirteenth resistor is connected to the other end of the ninth capacitor and grounded. One end of the ninth capacitor is connected with one end of the thirteenth resistor and the non-inverting input terminal of the third operational amplifier respectively, and the other end of the ninth capacitor is grounded; one end of the tenth capacitor is connected with the second output terminal of the third operational amplifier, and the other end of the tenth capacitor is grounded; The first output terminal of the third operational amplifier is used as the output terminal of the power control circuit, and the third output terminal of the third operational amplifier is grounded.
10. The radio frequency circuit of claim 8, wherein, The power function circuit comprises an eleventh capacitor, a twelfth capacitor, a fourteenth resistor and a fourth operational amplifier, One end of the fourteenth resistor is connected with the output terminal of the radio frequency detection circuit, and the other end of the fourteenth resistor is connected with the non-inverting input terminal of the fourth operational amplifier; One end of the eleventh capacitor is connected with the other end of the fourteenth resistor and the non-inverting input terminal of the fourth operational amplifier respectively, and the other end of the eleventh capacitor is grounded; One end of the twelfth capacitor is connected with the output terminal of the fourth operational amplifier, and the other end of the twelfth capacitor is grounded; The inverting input terminal of the fourth operational amplifier is connected with the output terminal of the fourth operational amplifier, and the output terminal of the fourth operational amplifier is used as the output terminal of the power function circuit.