Efficient broadband radio frequency rectifier based on coupling feedback network

Abstract

The invention provides a novel broadband rectifier which is integrated with an initial coupling feedback network (CFN) and is applied to the field of wireless power transmission. The framework of the rectifier adopts a transmission line, the transmission line is bent into an L shape, and the transmission line and the CFN form an impedance matching network together. The CFN has double functions: impedance matching is realized, rectified energy is recovered and fed back to a source, repeated rectification is carried out, and the rectification bandwidth is effectively widened. Through experimental manufacturing and testing of the rectifier, the result shows that the conversion efficiency of the rectifier in the frequency range of 0.6-2.5 GHz exceeds 50%, the peak efficiency reaches 70.6%, and the relative bandwidth reaches 122.5% under the conditions that the input power is 8dBm and the load is 1k omega.

Description

Technical Field

[0001] The present invention belongs to the technical field of radio frequency ambient energy harvesting, and specifically relates to a rectifier circuit composed of two Schottky diodes: diode D1 and diode D2, characterized in that: the capacitor C1 is connected to TL1; the other end of C1 is connected to the common connection point of TL2 and the coupling line. The anode of diode D2 is grounded, and the cathode of diode D1 is connected to the common terminal of capacitor C2 and resistor Rload. Background Art

[0002] Radio frequency rectifiers play a crucial role in the field of radio frequency ambient energy harvesting and are important functional devices for converting radio frequency beams into electrical energy to achieve efficient energy conversion.

[0003] Radio frequency rectifiers are crucial for the practicality of wireless energy harvesting devices and systems, especially in low-power application fields such as the Internet of Things (IoT) and wireless sensor networks (WSN). Therefore, the rectifier should have broadband characteristics.

[0004] Radio frequency rectification efficiency is a key indicator for evaluating the performance of radio frequency rectifier circuits. In the fields of microwave wireless energy transmission and wireless communication, there are requirements for high rectification efficiency in specific frequency bands for radio frequency rectifiers. This means that radio frequency rectifiers need to have efficient conversion capabilities. Summary of the Invention

[0005] The purpose of the present invention is to: in view of the deficiencies or improvement requirements in the above-mentioned existing technologies, provide an efficient broadband radio frequency rectifier based on a coupled feedback network. By adding a coupled line matching network on the basis of the rectifier circuit and matching the impedance with a transmission line, the circuit complexity can be reduced and the circuit area can be decreased. In addition, by introducing high-precision capacitors and inductors as impedance compression networks, the stability of the circuit is improved, and Schottky diodes are used to make it more suitable for implementation in high-frequency environments.

[0006] To achieve the above purpose, the technical solution adopted by the present invention is as follows:

[0007] An efficient broadband radio frequency rectifier based on a coupled transmission line matching network, which includes two capacitors: capacitor C1 and capacitor C2; a resistor Rload; a coupled feedback network; transmission lines TL1, TL2; two Schottky diodes: diode D1 and diode D2, characterized in that:

[0008] The capacitor C1 is connected to TL1; the other end of C1 is connected to the common connection point of TL2 and the coupling line. The anode of diode D2 is grounded, and the cathode of diode D1 is connected to the common terminal of capacitor C2 and resistor Rload.

[0009] Further, for the high-efficiency broadband RF rectifier based on a coupled feedback network, it is characterized in that: the capacitor C1 is used to isolate DC, and the element sizes are all cuboids with a length of 1.0 mm, a width of 0.5 mm, and a height of 0.3 mm.

[0010] Further, for the high-efficiency broadband RF rectifier based on a coupled feedback network, it is characterized in that: the impedance matching network is composed of a coupled line and a transmission line, wherein the coupled line is an asymmetric coupled line, and the characteristic impedance of the transmission line at the operating frequency is 78.68 Ω and the electrical length is 21.5°.

[0011] Further, for the high-efficiency broadband RF rectifier based on a coupled transmission line matching network, it is characterized in that: the operating frequency band of the RF rectifier is 0.6 GHz to 2.5 GHz.

[0012] Further, for the high-efficiency broadband RF rectifier based on a coupled transmission line matching network, it is characterized in that: when the input power of the RF rectifier is 0 dBm, the RF rectification efficiency is above 40% within the bandwidth of 0.8 GHz to 1.9 GHz.

[0013] Further, for the high-efficiency broadband RF rectifier based on a coupled transmission line matching network, it is characterized in that: when the input power of the RF rectifier is 5 dBm, the RF rectification efficiency is above 50% within the bandwidth of 0.8 GHz to 1.9 GHz.

[0014] Further, for the high-efficiency broadband RF rectifier based on a coupled transmission line matching network, it is characterized in that: when the input power of the RF rectifier is 8 dBm, the RF rectification efficiency is above 50% within the bandwidth of 0.6 GHz to 2.5 GHz.

[0015] Further, for the high-efficiency broadband RF rectifier based on a coupled transmission line matching network, it is characterized in that: when the input power of the RF rectifier is 8 dBm and at a frequency of 1.2 GHz, the maximum RF rectification efficiency is 70.6%.

[0016] The beneficial effects of the present invention adopting the above solution are as follows:

[0017] By adopting a coupled feedback network, the present invention effectively increases the operating bandwidth of the RF rectifier, effectively improves the rectification efficiency of the RF rectifier, and at the same time adopts a voltage-doubling rectifier circuit structure to increase the output voltage. Moreover, it has the advantages of simple structure, small size, low cost, wide frequency band, high efficiency, etc. Description of the Drawings

[0018] Figure 1 It is the RF circuit structure diagram of the present invention.

[0019] Figure 2 shows the conversion efficiency diagrams of the RF rectifier in the embodiments of the present invention at input powers of 0 dBm, 5 dBm, and 8 dBm respectively. Detailed implementation manners

[0020] The present invention will be further described in conjunction with the accompanying drawings and specific implementation manners.

[0021] As Figure 1 shown, an efficient broadband RF rectifier based on a coupled feedback network provided in the embodiments of the present invention includes: two capacitors: capacitor C1 and capacitor C2; a resistor Rload; transmission lines (TL1 and TL2) with a length of 4.4 mm and a width of 0.2 mm and a length of 18.6 mm and a width of 0.3 mm; a coupled transmission line with a length of 10.0 mm, a width of 1.5 mm, and a spacing of 0.2 mm; two Schottky diodes: diode D1 and diode D2, characterized in that:

[0022] The capacitor C1 is connected to TL1; the other end of C1 is connected to the common connection point of TL2 and the coupled line. The anode of diode D2 is grounded, and the cathode of diode D1 is connected to the common end of capacitor C2 and resistor Rload.

[0023] For the accuracy and convenience of the scheme implementation, further, the impedance matching network is composed of a lumped parameter element coupled line feedback network connected to transmission lines TL1 and TL2, and the finally determined impedance matching network element parameters are shown in Table 1. Table 1 Impedance matching network parameters

[0024] Further, for the efficient broadband RF rectifier based on a coupled transmission line matching network, it is characterized in that: the value of capacitor C1 is 100 pF, the dielectric constant of the used substrate is 2.65, the thickness is 0.8 mm, the length is 17.8 mm, and the width is 16.6 mm.

[0025] Further, after being rectified by voltage doubling and passing through a DC filtering structure, it is then connected to the load resistor Rload. The finally determined component parameters of the DC filter are shown in Table 2. Table 2 Component parameters of the DC filter

[0026] Further, Figure 2 shows the efficiency of this RF rectifier. It can be seen from the figure that when the input power of the RF rectifier is 0 dBm, the RF rectification efficiency is above 40% within the bandwidth of 0.8 GHz to 1.9 GHz.

[0027] Further, Figure 2 shows the efficiency of this RF rectifier. It can be seen from the figure that when the input power of the RF rectifier is 5 dBm, the RF rectification efficiency is above 50% within the bandwidth of 0.8 GHz to 1.9 GHz.

[0028] Further, Figure 2 shows the efficiency of this RF rectifier. It can be seen from the figure that when the input power of the RF rectifier is 8 dBm, the RF rectification efficiency is above 50% within the bandwidth of 0.6 GHz to 2.5 GHz.

[0029] Brief working principle of the present invention:

[0030] In order to achieve the small volume and wide bandwidth performance of the RF rectifier, an RF rectifier with an impedance matching network based on a coupled-line feedback network is adopted, which effectively improves the working bandwidth and conversion efficiency of the RF rectifier. Then, a voltage multiplier rectification structure is used to increase the output DC voltage.

Claims

1. A high-efficiency broadband radio frequency rectifier based on a coupled feedback network, comprising two capacitors: capacitor C1 and capacitor C2; a resistor Rload; transmission lines (TL1 and TL2) with a length of 4.4 mm, a width of 0.2 mm and a length of 18.6 mm, a width of 0.3 mm; coupled transmission lines with a length of 10.0 mm, a width of 1.5 mm and a spacing of 0.2 mm; two Schottky diodes: diode D1 and diode D2, characterized in that: The capacitor C1 is connected to TL1, and the other end of C1 is connected to the common point of TL2 and the coupling line. The anode of the diode D2 is grounded, and the cathode of the diode D1 is connected to the common end of the capacitor C2 and the resistor Rload.

2. The high-efficiency broadband radio frequency rectifier based on a coupled feedback network according to claim 1, characterized in that: The DC component is isolated by capacitor C1, wherein the component size is a rectangular parallelepiped with a length of 1.0 mm, a width of 0.5 mm, and a height of 0.3 mm.

3. The high-efficiency broadband radio frequency rectifier based on a coupled feedback network according to claim 1, characterized in that: The impedance matching network consists of a coupling line and a transmission line, wherein the coupling line is a symmetrical coupling line, and the characteristic impedance of the transmission line is 78.68Ω and the electrical length is 21.5° at the operating frequency.

4. The high-efficiency broadband radio frequency rectifier based on a coupled feedback network according to claim 1, characterized in that: The operating frequency band of the RF rectifier is 0.6GHz to 2.5GHz.

5. The high-efficiency broadband radio frequency rectifier based on a coupled feedback network according to claim 1, characterized in that: When the input power of the radio frequency rectifier is 0 dBm, the radio frequency rectification efficiency is above 40% within a bandwidth of 0.8 GHz to 1.9 GHz.

6. The high-efficiency broadband radio frequency rectifier based on a coupled feedback network according to claim 1, characterized in that: When the input power of the radio frequency rectifier is 5dBm, the radio frequency rectification efficiency is above 50% within the bandwidth of 0.8GHz to 1.9GHz.

7. The high-efficiency broadband radio frequency rectifier based on a coupled feedback network according to claim 1, characterized in that: When the input power of the radio frequency rectifier is 8dBm, the radio frequency rectification efficiency is above 50% within the bandwidth of 0.6GHz to 2.5GHz.

8. The high-efficiency broadband radio frequency rectifier based on a coupled feedback network according to claim 1, characterized in that: When the input power of the RF rectifier is 8 dBm and the frequency is 1.2 GHz, the maximum RF rectification efficiency is 70.6%.

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