Loop filter applied to satellite-borne communication chip

Abstract

The invention belongs to the technical field of integrated circuits, and particularly relates to an anti-radiation loop filter applied to a satellite-borne wireless communication system. The circuit structure comprises a radiation-proof loop filter core circuit, a power detection circuit, an analog-to-digital converter and a control module. An input signal is input to the radiation-proof loop filter core circuit, and a voltage signal is generated and output to the power detection circuit. The power detection circuit processes the received voltage signal, outputs a processing result to the analog-to-digital converter, receives an instruction of the control module circuit and outputs a final signal; the analog-to-digital converter converts a processing result output by the power detection circuit into a digital signal and outputs the digital signal to the control module; and the control module performs judgment according to the input digital signal, generates a control signal for controlling the working mode of the anti-radiation loop filter core circuit, and generates a control signal for controlling the power detection circuit and the analog-to-digital converter. Wherein the core circuit architecture of the radiation-proof loop filter is a three-order passive low-pass filter with a replaceable key capacitor, and the circuit can switch the key capacitor in actual work through a switch. By utilizing the structure, the probability of circuit failure caused by space irradiation can be obviously reduced, and the anti-irradiation performance and the stability of a satellite-borne wireless communication system are improved.

Description

Technical Field

[0001] The present invention belongs to the technical field of integrated circuits, and particularly relates to a loop filter. Background Art

[0002] A loop filter is an important part of a phase-locked loop. Its main function is to filter out high-frequency noise and signals, while allowing low-frequency signals to pass through, in order to achieve phase locking and tracking. The loop filter usually consists of a low-pass filter, which can be passive or active.

[0003] Currently, the mainstream architectures of loop filters include types such as RC integral filters, passive proportional integral filters, active proportional integral filters, digital loop filters, etc. Among them, the passive proportional integral filter is a simple analog filter. Its main function is to smooth the high-frequency noise of the input signal while maintaining the integrity of the low-frequency signal, in order to achieve stable and precise control of the system. The passive proportional integral filter has a simple structure and low cost, can effectively suppress high-frequency noise, and can provide good phase margin and stability.

[0004] With the progress of technology and the continuous expansion of the communication application field, people have put forward more requirements for loop filter circuits. In the aerospace field, the working environment of spaceborne chips is the space with intense irradiation. The circuit modules in the chips are affected by irradiation, having a higher failure probability and a shorter expected life. Therefore, in order to improve the performance of spaceborne chips, it is necessary to effectively utilize chip anti-irradiation technology to improve system stability and reliability. Summary of the Invention

[0005] The purpose of the present invention is to propose an anti-irradiation loop filter applied to spaceborne communication chips.

[0006] The loop filter circuit structure proposed by the present invention includes: an anti-irradiation loop filter core circuit, a power detection circuit, an analog-to-digital converter, and a control module. The input signal is input to the anti-irradiation loop filter core circuit, generating a voltage signal and outputting it to the power detection circuit; the power detection circuit processes the voltage signal it receives, outputs the processing result to the analog-to-digital converter, and receives the instruction of the control module circuit to output the final signal; the analog-to-digital converter converts the processing result output by the power detection circuit into a digital signal and outputs it to the control module; the control module makes a judgment based on the input digital signal, generates a control signal for controlling the working mode of the anti-irradiation loop filter core circuit, and generates control signals for controlling the power detection circuit and the analog-to-digital converter.

[0007] In the present invention, the core circuit of the anti-radiation loop filter consists of a third-order passive low-pass filter, a backup capacitor for a key capacitor, and a single-pole double-throw numerically controlled switch; whether the key capacitor and its backup capacitor are connected to the circuit is controlled by the numerically controlled switch, and only one of the two capacitors is used during actual normal operation; the numerically controlled switch switches the capacitor actually connected to the circuit according to the signal from the control module in the system, thereby greatly improving the anti-radiation performance and stability of the system. BRIEF DESCRIPTION OF THE DRAWINGS

[0008] Figure 1 It is a schematic structural diagram of the anti-radiation loop filter of the present invention.

[0009] Figure 2 It is a schematic diagram of the core circuit of the anti-radiation loop filter. DETAILED DESCRIPTION OF THE INVENTION

[0010] The present invention will be described in more detail with reference to the accompanying drawings. In the various drawings, like elements are denoted by like reference numerals. For the sake of clarity, the various parts in the drawings are not drawn to scale. In addition, some well-known parts may not be shown in the figures.

[0011] Many specific details of the present invention are described hereinafter, such as the structure, materials, dimensions, processing techniques and technologies of the device, in order to understand the present invention more clearly. However, as those skilled in the art can understand, the present invention can be implemented without these specific details.

[0012] Figure 1 It shows a schematic structural diagram of the spaceborne anti-radiation loop filter of the present invention.

[0013] As Figure 1 shown, the spaceborne anti-radiation loop filter 100 in the present invention includes an anti-radiation loop filter core circuit 101, a power detection circuit 102, a control module 103, and an analog-to-digital converter 104. The external input signal vctrlin serves as the input signal of the anti-radiation loop filter core circuit 101, and the output signal vctrl of the anti-radiation loop filter core circuit 101 is transmitted to the power detection circuit 102. The power detection circuit 102 outputs vctrlo as the output signal of the entire loop filter circuit. The power detection circuit 102 outputs pdout to the analog-to-digital converter 104, the analog-to-digital converter 104 outputs adout to the control module 103, and the control module 103 outputs Ctrl<1> to the anti-radiation phase-locked loop core circuit 101, outputs ctrl2 to the power detection circuit 102, and outputs ctrl3 to the analog-to-digital converter 104.

[0014] Figure 2 It shows a schematic diagram of the core circuit of the anti-radiation loop filter in the present invention.

[0015] As Figure 2 shown, the core circuit of the anti-radiation loop filter includes a numerically controlled switch S1, two resistors R1 - R2, and four capacitors C1 - C4. When the core circuit of the anti-radiation loop filter receives a control signal to select the branch where the key capacitor C2 is located, the switch S1 is connected to the fixed terminal 1.1. When the core circuit of the anti-radiation loop filter receives a control signal to select the branch where the key capacitor C4 is located, the switch S1 is connected to the fixed terminal 1.2. One end of the resistor R1 is connected to the input signal vctrlin, and the other end is connected to the capacitor C1. One end of the capacitor C1 is connected to the resistor R1, and the other end is grounded. The moving terminal of the switch S1 is connected to the input signal vctrlin. One end of the capacitor C2 is connected to the fixed terminal 1.1 of the switch S1, and the other end is grounded. One end of the capacitor C4 is connected to the fixed terminal 1.2 of the switch S1, and the other end is grounded. One end of the resistor R2 is connected to the input signal vctrlin, and the other end is connected to the output signal vctrl. One end of the capacitor C3 is connected to the output signal vctrl, and the other end is grounded. The core of this circuit structure is that the control signal can change the state of the switch S1. When space radiation causes the key capacitor in operation to fail, the control signal can change the switch state to make the standby capacitor replace the failed capacitor and be connected to the circuit, thus greatly improving the stability and reliability of the system.

Claims

1. An anti-radiation loop filter applied to a spaceborne wireless communication system. The circuit structure of the present invention includes: An anti-radiation loop filter core circuit, a power detection circuit, an analog-to-digital converter, and a control module. The input signal is input to the anti-radiation loop filter core circuit, generating a voltage signal and outputting it to the power detection circuit; the power detection circuit processes the received voltage signal, outputs the processing result to the analog-to-digital converter, and receives the instruction from the control module circuit to output the final signal; The analog-to-digital converter converts the processing result output by the power detection circuit into a digital signal and outputs it to the control module; the control module makes a judgment based on the input digital signal, generates a control signal for controlling the working mode of the anti-radiation loop filter core circuit, and generates control signals for controlling the power detection circuit and the analog-to-digital converter.

2. The anti-radiation loop filter applied to the spaceborne communication chip according to claim 1, characterized in that The anti-radiation loop filter core circuit consists of a third-order passive low-pass filter, a spare capacitor of a key capacitor, and a single-pole double-throw numerically controlled switch; whether the key capacitor and its spare capacitor are connected to the circuit is controlled by the numerically controlled switch, and only one of the above two capacitors is used during actual normal operation; the numerically controlled switch switches the capacitor actually connected to the circuit according to the signal from the control module in the system, thus greatly improving the anti-radiation performance and stability of the system.

3. The phase-locked loop applied to the spaceborne communication chip according to claim 2, characterized in that, The anti-radiation loop filter core circuit altogether includes a numerically controlled switch S1, two resistors R1 - R2, and four capacitors C1 - C4; when the anti-radiation loop filter core circuit receives a control signal to select the branch where the key capacitor C2 is located, the switch S1 is connected to the fixed terminal 1.1; when the anti-radiation loop filter core circuit receives a control signal to select the branch where the key capacitor C4 is located, the switch S1 is connected to the fixed terminal 1.2; one end of the resistor R1 is connected to the input signal vctrlin, and the other end is connected to the capacitor C1; one end of the capacitor C1 is connected to the resistor R1, and the other end is grounded; the moving end of the switch S1 is connected to the input signal vctrlin; one end of the capacitor C2 is connected to the fixed terminal 1.1 of the switch S1, and the other end is grounded; one end of the capacitor C4 is connected to the fixed terminal 1.2 of the switch S1, and the other end is grounded; one end of the resistor R2 is connected to the input signal vctrlin, and the other end is connected to the output signal vctrl; one end of the capacitor C3 is connected to the output signal vctrl, and the other end is grounded. The core of this circuit structure is that the control signal can change the state of the switch S1. When space radiation causes the key capacitor in operation to fail, the control signal can change the switch state to make the spare capacitor replace the failed capacitor and be connected to the circuit, thus greatly improving the stability and reliability of the system.

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