A microstrip line structure and circuit thereof

Abstract

The present invention discloses a microstrip line structure and a circuit thereof, which is a low-power and high-efficiency rectifier circuit with a self-protection function, comprising a top microstrip structure, an intermediate dielectric substrate and a bottom metal floor, wherein the top microstrip structure is arranged on the upper surface of the intermediate dielectric substrate, and the bottom metal floor is arranged on the lower surface of the intermediate dielectric substrate; the top microstrip structure comprises an input port, a DC blocking capacitor, a matching circuit, a Schottky diode, a low-pass filter network and an output port, and the beneficial effect of the present invention is that the present invention only uses a PIN diode to achieve control of the output voltage of the low-power rectifier circuit, and avoids the rectifier circuit outputting a higher DC voltage at high power, resulting in the low-power rectifier diode being reversely broken down. While not affecting the low-power rectification efficiency of the circuit, the rectifier circuit is protected from damage at high power.

Description

Technical Field

[0001] The invention belongs to the technical field of power electronics, and in particular relates to a microstrip line structure and a circuit thereof. Background Art

[0002] With the rapid development of wireless communication technology, the electromagnetic wave energy in the environment is increasing, including mobile communication, WIFI, Bluetooth, broadcast and other signals. On the other hand, with the rapid layout of the Internet of Things, a large number of wireless sensors are used. At present, most wireless sensors rely on batteries for power supply, and whether they can work normally is affected by the battery life. Regular replacement of batteries will increase costs and pollution problems; in addition, the distribution location of some wireless sensors may be inaccessible to people, making it difficult to replace batteries. Therefore, the electromagnetic wave energy in the environment can be collected to power wireless sensors.

[0003] The rectifier circuit is the core component of the environmental electromagnetic energy recovery system. Since the energy density of electromagnetic waves in the environment is still relatively low, the power input to the rectifier circuit is also relatively low. At low power, the efficiency of the rectifier circuit is low; when the power increases, the output voltage of the circuit increases, and the rectifier diode may be reversely broken down, causing the rectifier circuit to fail to work.

[0004] At present, there is still little research on low-power rectifier circuits. The reverse breakdown voltage of low-power rectifier diodes is low, and they are easily reversely broken down under high power. It is urgent to solve the problem that low-power rectifier diodes are easily reversely broken down. Summary of the invention

[0005] In order to solve the problem that low-power rectifier diodes are prone to reverse breakdown, the present invention provides a microstrip line structure and a circuit thereof.

[0006] The microstrip line structure comprises:

[0007] An input terminal module, the input terminal module is used to guide the electromagnetic wave into the rectifier circuit,

[0008] A first capacitor, the first capacitor is used to isolate the output DC voltage from entering the signal source;

[0009] A matching circuit module, wherein the input end module and the matching circuit module are connected via the first capacitor, wherein the first capacitor is connected to the input end of the matching circuit module;

[0010] An output end module, the output end module is connected to the output end of the matching circuit module;

[0011] A low-pass filter network circuit module, wherein the low-pass filter network circuit is connected to the output end module.

[0012] Further, the input end module is configured as a first microstrip line, and one end of the first microstrip line guides the electromagnetic wave into the rectifier circuit;

[0013] The matching circuit module includes a second microstrip line, a first diode, a third microstrip line and a fourth microstrip line; the first capacitor is connected across the output end of the first microstrip line and the input end of the second microstrip line;

[0014] The first microstrip line, the second microstrip line and the fourth microstrip line are sequentially arranged in a straight line; the output end of the second microstrip line is connected to the input end of the fourth microstrip line;

[0015] The output end of the second microstrip line is connected to the input end of the third microstrip line by bridging the first diode, and a metallized via is provided at the end of the third microstrip line;

[0016] The low-pass filter network circuit module includes a second capacitor and a sixth microstrip line;

[0017] The output end module includes a fifth microstrip line, a second diode and a seventh microstrip line; the output end module is used to output a DC signal generated by rectification; the input end of the fifth microstrip line is connected to the output end of the fourth microstrip line, the second diode is set as a PIN diode, and the second diode is used to adjust the output DC voltage; the seventh microstrip line is connected to the fifth microstrip line through the second diode connected across the fifth microstrip line;

[0018] The end of the seventh microstrip line is provided with a metallized via hole;

[0019] The input end of the sixth microstrip line is connected to the fifth microstrip line through the second capacitor connected across the input end of the sixth microstrip line; and a metallized via hole is provided at the end of the sixth microstrip line.

[0020] Furthermore, the third microstrip line is arranged perpendicularly to the second microstrip line; the sixth microstrip line is arranged perpendicularly to the fifth microstrip line; and the seventh microstrip line is arranged perpendicularly to the fifth microstrip line.

[0021] Furthermore, the first diode is a Schottky diode, which is used to convert input electromagnetic wave energy into direct current energy.

[0022] Furthermore, the first capacitor is a DC blocking capacitor, and the DC blocking capacitor is used to prevent the DC signal generated by the rectifier diode from entering the signal source.

[0023] Also provided is a circuit, comprising a top microstrip structure, an intermediate dielectric substrate and a bottom metal floor, wherein the top microstrip structure is arranged on the upper surface of the intermediate dielectric substrate, and the bottom metal floor is arranged on the lower surface of the intermediate dielectric substrate.

[0024] The top microstrip structure includes an input port, a DC blocking capacitor, a matching circuit, a Schottky diode, a low-pass filter network and an output port, wherein the DC blocking capacitor is connected across the input port and the input end of the low-pass filter network, the Schottky diode is connected across the matching circuit, and the output end of the low-pass filter network is connected to the output port. The present invention introduces a PIN diode at the output end to adjust the output DC voltage, thereby preventing the low-power rectifier circuit from outputting a higher DC voltage at high power, protecting the low-power rectifier diode from reverse breakdown, and not affecting the rectification efficiency at low power.

[0025] Furthermore, the first layer of microstrip line includes an input terminal module,

[0026] The input end module is configured as a first microstrip line, one end of which guides electromagnetic waves into the rectifier circuit;

[0027] The matching circuit module includes a second microstrip line, a first diode, a third microstrip line and a fourth microstrip line; the first capacitor is connected across the output end of the first microstrip line and the input end of the second microstrip line;

[0028] The first microstrip line, the second microstrip line and the fourth microstrip line are sequentially arranged in a straight line; the output end of the second microstrip line is connected to the input end of the fourth microstrip line;

[0029] The output end of the second microstrip line is connected to the input end of the third microstrip line by bridging the first diode. The end of the third microstrip line is provided with a metallized via hole, which is connected to the bottom metal floor through the metallized via hole to achieve grounding and form a short circuit.

[0030] The low-pass filter network circuit module includes a second capacitor and a sixth microstrip line;

[0031] The output end module includes a fifth microstrip line, a second diode and a seventh microstrip line; the output end module is used to output a DC signal generated by rectification; the input end of the fifth microstrip line is connected to the output end of the fourth microstrip line, the second diode is set as a PIN diode, and the second diode is used to adjust the output DC voltage; the seventh microstrip line is connected to the fifth microstrip line through the second diode connected across the fifth microstrip line;

[0032] The end of the seventh microstrip line is provided with a metallized via hole, and is connected to the bottom metal floor through the metallized via hole to achieve grounding and form a short circuit.

[0033] The input end of the sixth microstrip line is connected to the fifth microstrip line through the second capacitor connected across it; the end of the sixth microstrip line is connected to the underlying metal floor through a metallized via to achieve grounding, forming a short circuit; the low-pass filter network can filter out the baseband signal and the higher harmonics generated by rectification.

[0034] . Further, the third microstrip line is arranged perpendicular to the second microstrip line;

[0035] The sixth microstrip line is arranged perpendicular to the fifth microstrip line;

[0036] The seventh microstrip line is arranged perpendicular to the fifth microstrip line.

[0037] Furthermore, the length L1 of the first microstrip line is 5 mm, and the width W1 is 2.7 mm; the length L2 of the second microstrip line is 6.7 mm, and the width W2 is 1.1 mm; the length L3 of the third microstrip line is 12 mm, and the width W3 is 0.2 mm; the length L4 of the fourth microstrip line is 20.5 mm, and the width W4 is 0.5 mm; the length L5 of the fifth microstrip line is 9.3 mm, and the width W5 is 2 mm; the length L6 of the sixth microstrip line is 1.5 mm, and the width W6 is 1 mm; the length L7 of the seventh microstrip line is 1 mm, and the width W7 is 1.5 mm; the capacitance of the first capacitor is 22 pF; the first diode is SMS7630; the capacitance of the second capacitor is 100 pF; the capacitance of the second diode is SMP1345.

[0038] Furthermore, the first capacitor is a DC blocking capacitor, and the DC blocking capacitor is used to prevent the DC signal generated by the rectifier diode from entering the signal source.

[0039] The beneficial effect of the present invention is that the present invention uses only PIN diodes to achieve control of the output voltage of the low-power rectifier circuit, avoiding the rectifier circuit outputting a higher DC voltage at high power, which causes the low-power rectifier diode to be reversely broken down. While not affecting the low-power rectification efficiency of the circuit, the rectifier circuit is protected from damage at high power. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] Figure 1 It is a structural schematic diagram of a low-power and high-efficiency rectifier circuit with a self-protection function in an embodiment of the present invention;

[0041] Figure 2 It is a dimensioning diagram of a low-power and high-efficiency rectifier circuit with a self-protection function in an embodiment of the present invention;

[0042] Figure 3 Graph showing conversion efficiency and output DC voltage of a low-power and high-efficiency rectifier circuit with self-protection function in an embodiment of the present invention.

[0043] Among them, 1. the first microstrip line, 2. the DC blocking capacitor, 3. the second microstrip line, 4. the first diode, 5. the third microstrip line, 6. the fourth microstrip line, 7. the fifth microstrip line, 8. the second capacitor, 9. the sixth microstrip line, 10. the second diode, 11. the seventh microstrip line. DETAILED DESCRIPTION

[0044] In order to enable those skilled in the art to better understand the scheme of the present invention, the technical scheme in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present invention.

[0045] It should be noted that the terms "first", "second", etc. in the specification and claims of the present invention and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchangeable where appropriate, so that the embodiments of the present invention described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "including" and "having" and any of their variations are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units that are clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0046] like Figure 1 As shown, an embodiment of the present invention provides a circuit, including a top microstrip structure, an intermediate dielectric substrate and a bottom metal floor, wherein the top microstrip structure is arranged on the upper surface of the intermediate dielectric substrate, and the bottom metal floor is arranged on the lower surface of the intermediate dielectric substrate.

[0047] The top microstrip structure includes an input port, a DC blocking capacitor 2, a matching circuit, a Schottky diode, a low-pass filter network and an output port, wherein the DC blocking capacitor is connected across the input port and the input end of the low-pass filter network, the Schottky diode is connected across the matching circuit, and the output end of the low-pass filter network is connected to the output port. The present invention adjusts the output DC voltage by introducing a PIN diode at the output end, thereby preventing the low-power rectifier circuit from outputting a higher DC voltage at high power, protecting the low-power rectifier diode from reverse breakdown, and not affecting the rectification efficiency at low power.

[0048] In an optional embodiment of the present invention, the input port uses the left end of the first microstrip line 1 to guide the electromagnetic wave into the rectifier circuit.

[0049] The DC blocking capacitor 2 is a first capacitor, which is connected across the output end of the first microstrip line 1 and the input end of the second microstrip line 3 , and has the function of preventing the DC signal generated by the rectifier diode from entering the signal source.

[0050] The matching circuit includes a second microstrip line 3, a third microstrip line 5 and a fourth microstrip line 6, which realize impedance matching between the rectifier circuit and the signal source and reduce reflection; the first microstrip line 1, the second microstrip line 3 and the fourth microstrip line 6 are arranged in a straight line in sequence; the output end of the second microstrip line 3 is connected to the input end of the fourth microstrip line 6, and the output end of the second microstrip line 3 is connected to the input end of the third microstrip line 5 by bridging the first diode 4, and the end of the third microstrip line 5 is connected to the bottom metal floor through a metallized via to achieve grounding, forming a short circuit.

[0051] The first diode 4 is a Schottky diode, which is used to convert the input electromagnetic wave energy into direct current energy.

[0052] The low-pass filter network includes a second capacitor 8 and a sixth microstrip line 9; the input end of the sixth microstrip line 9 is connected to the fifth microstrip line 7 through the second capacitor 8, and the end of the sixth microstrip line 9 is connected to the bottom metal floor through a metallized via to achieve grounding, forming a short circuit; the low-pass filter network can filter out the baseband signal and the higher harmonics generated by rectification.

[0053] The output end includes a fifth microstrip line 7, a second diode 10 and a seventh microstrip line 11, which are used to output a DC signal generated by rectification; the input end of the fifth microstrip line 7 is connected to the output end of the fourth microstrip line 6, the second diode 10 is a PIN diode, which is used to adjust the output DC voltage, and the seventh microstrip line 11 is connected to the fifth microstrip line 7 through the jumper-connected second diode 10, and the end of the seventh microstrip line 11 is connected to the underlying metal floor through a metallized via to achieve grounding, forming a short circuit.

[0054] The third microstrip line 5 is perpendicular to the second microstrip line 3 , the sixth microstrip line 9 is perpendicular to the fifth microstrip line 7 , and the seventh microstrip line 11 is perpendicular to the fifth microstrip line 7 .

[0055] The present invention introduces a PIN diode at the output end of the rectifier circuit so that the load value of the rectifier circuit changes with the output voltage. Specifically, when the input electromagnetic wave power is high, the output DC voltage increases, the PIN diode gradually turns on, resulting in a decrease in the resistance of the PIN diode, and finally reducing the load value, thereby avoiding the output of a higher DC voltage and protecting the low-power rectifier diode from reverse breakdown.

[0056] like Figure 2As shown, the intermediate dielectric substrate used in the embodiment of the present invention is F4B, which has a thickness of 1 mm, a relative dielectric constant of 2.65, a loss tangent value of 0.002, and a thickness of both the bottom metal floor and the top microstrip structure of 0.0036 mm. The specific dimensions are set as follows: the length of the first microstrip line 1 of the input port is L1=5mm, the width is W1=2.7mm, the length of the second microstrip line 3 is L2=6.7mm, the width is W2=1.1mm, the length of the third microstrip line 5 is L3=12mm, the width is W3=0.2mm, the length of the fourth microstrip line 6 is L4=20.5mm, the width is W4=0.5mm, the length of the fifth microstrip line 7 is L5=9.3mm, the width is W5=2mm, the length of the sixth microstrip line 9 is L6=1.5mm, the width is W6=1mm, the length of the seventh microstrip line 11 is L7=1mm, the width is W7=1.5mm, the capacitance of the DC blocking capacitor 2 is 22pF, the first diode 4 is SMS7630, the capacitance of the second capacitor 8 is 100pF, and the capacitance of the second diode 10 is SMP1345.

[0057] Figure 3 The figure shows the conversion efficiency and output DC voltage of the rectifier circuit without PIN diode, the rectifier circuit with limiter and the rectifier circuit with PIN diode when the input power range is -10dBm to 20dBm. The horizontal axis numbers in the figure are the input power values ​​in dBm; the vertical axis numbers on the left are the rectification efficiency values ​​in %; the vertical axis numbers on the right are the output DC voltage values ​​in V. It can be seen from the figure that in the range of -10dBm—0dBm, the introduction of PIN diodes will hardly affect the efficiency of the rectifier circuit. When the input power increases, the output DC voltage also increases. The PIN diode can limit the output DC voltage value so that when the input power reaches 20dBm, the output voltage is still lower than the reverse breakdown voltage of the diode by 2V, which can protect the circuit from reverse breakdown under high power. At the same time, the figure also compares the performance of the rectifier circuit with the limiter. Because the limiter has a large insertion loss, it will affect the efficiency of the rectifier circuit in the entire power range, and cannot ensure that the output voltage of the rectifier circuit is lower than the reverse breakdown voltage under high power.

[0058] Those skilled in the art will appreciate that the embodiments described herein are intended to help readers understand the principles of the present invention, and should be understood that the protection scope of the present invention is not limited to such specific statements and embodiments. Those skilled in the art can make various other specific variations and combinations that do not deviate from the essence of the present invention based on the technical revelations disclosed by the present invention, and these variations and combinations are still within the protection scope of the present invention.

Claims

1. A microstrip line structure, characterized in that: include An input terminal module, the input terminal module is used to guide the electromagnetic wave into the rectifier circuit, A first capacitor, the first capacitor is used to isolate the output DC voltage from entering the signal source; A matching circuit module, wherein the input end module and the matching circuit module are connected via the first capacitor, wherein the first capacitor is connected to the input end of the matching circuit module; An output end module, the output end module is connected to the output end of the matching circuit module; A low-pass filter network circuit module, wherein the low-pass filter network circuit is connected to the output end module; The input end module is configured as a first microstrip line, one end of which guides electromagnetic waves into the rectifier circuit; The matching circuit module includes a second microstrip line, a first diode, a third microstrip line and a fourth microstrip line; the first capacitor is connected across the output end of the first microstrip line and the input end of the second microstrip line; The first microstrip line, the second microstrip line and the fourth microstrip line are sequentially arranged in a straight line; the output end of the second microstrip line is connected to the input end of the fourth microstrip line; The output end of the second microstrip line is connected to the input end of the third microstrip line by bridging the first diode, a metallized via is provided at the end of the third microstrip line, and the end of the third microstrip line is connected to the bottom metal floor through the metallized via to achieve grounding, forming a short circuit; The low-pass filter network circuit module includes a second capacitor and a sixth microstrip line; The output end module includes a fifth microstrip line, a second diode and a seventh microstrip line; the output end module is used to output a DC signal generated by rectification; the input end of the fifth microstrip line is connected to the output end of the fourth microstrip line, the second diode is set as a PIN diode, and the second diode is used to adjust the output DC voltage; the seventh microstrip line is connected to the fifth microstrip line through the second diode connected across the fifth microstrip line; The end of the seventh microstrip line is provided with a metallized via hole; the end of the seventh microstrip line is connected to the bottom metal floor through the metallized via hole to achieve grounding, forming a short circuit; The input end of the sixth microstrip line is connected to the fifth microstrip line through the second capacitor connected across it; a metallized via is provided at the end of the sixth microstrip line, and the end of the sixth microstrip line is connected to the bottom metal floor through the metallized via to achieve grounding, forming a short circuit.

2. The microstrip line structure according to claim 1, characterized in that: The third microstrip line is arranged perpendicular to the second microstrip line; The sixth microstrip line is arranged perpendicular to the fifth microstrip line; The seventh microstrip line is arranged perpendicular to the fifth microstrip line.

3. The microstrip line structure according to claim 1, characterized in that: The first diode is a Schottky diode, which is used to convert input electromagnetic wave energy into direct current energy.

4. The microstrip line structure according to claim 1, characterized in that: The first capacitor is a DC blocking capacitor, which is used to prevent a DC signal generated by a rectifier diode from entering a signal source.

5. A circuit, characterized in that: include A first layer of microstrip line, wherein the first layer of microstrip line structure is the microstrip line structure according to any one of claims 1 to 4; A second dielectric substrate, wherein the first layer of microstrip lines is on an upper surface of the second dielectric substrate; The third metal floor is located on the lower surface of the second dielectric substrate.

6. The circuit according to claim 5, characterized in that The length L1 of the first microstrip line is 5 mm, and the width W1 is 2.7 mm; The second microstrip line has a length L2=6.7 mm and a width W2=1.1 mm; The length L3 of the third microstrip line is 12 mm, and the width W3 is 0.2 mm; The length L4 of the fourth microstrip line is 20.5 mm, and the width W4 is 0.5 mm; The fifth microstrip line has a length L5=9.3 mm and a width W5=2 mm; The sixth microstrip line has a length L6 of 1.5 mm and a width W6 of 1 mm; The length L7 of the seventh microstrip line is 1 mm, and the width W7 is 1.5 mm; The capacitance of the first capacitor is 22pF; The first diode is SMS7630; The capacitance of the second capacitor is 100pF; The capacitance of the second diode is SMP1345.

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