Frequency-selective high-efficiency broadband radio frequency rectifier adopting double-branch structure

Abstract

The invention introduces a frequency-selective high-efficiency broadband radio frequency rectifier adopting a double-branch structure, and the design successfully constructs a novel matching network based on frequency selection through fine modeling of lumped parameter elements and distribution parameters. In the design process, firstly, the microstrip line at the cathode of the diode is meticulously designed, and the microstrip line is endowed with the frequency selection characteristic. And then the transmission line is finely adjusted to ensure that the impedance of the transmission line can be perfectly matched with a source end. According to the radio frequency rectifier, under the conditions that the input power is 8dBm and the terminal load is 700 ohms, the rectification efficiency exceeding 60% can be achieved within the broadband range of 1.3-3.2 GHz, and meanwhile the maximum measurement efficiency can reach 71%. Even if the input power is reduced to 5dBm, the rectifier can still keep more than 50% of measurement efficiency in the frequency range of 1.3-3.3 GHz. The radio frequency rectifier provided by the invention has the remarkable advantages of low cost, simple structure, wide frequency band coverage, high conversion efficiency and the like, and provides an efficient and economical scheme for radio frequency energy conversion.

Description

Technical Field

[0001] The present invention belongs to the technical field of radio frequency ambient energy harvesting, and particularly relates to a frequency-selective high-efficiency broadband radio frequency rectifier adopting a dual-branch structure. Background Art

[0002] A radio frequency rectifier is a core component in the field of radio frequency energy harvesting. Its key function is to effectively convert radio frequency signals in the surrounding environment into electrical energy, thereby achieving efficient energy conversion.

[0003] In recent years, wireless power transmission and radio frequency energy harvesting technologies have received increasing attention due to their potential in fields such as electric vehicles, mobile devices, the Internet of Things, and biomedical implant devices, and have attracted great interest from people.

[0004] At the same time, the efficiency of the microwave rectifier directly affects the performance of the entire energy transmission system. A high-efficiency rectifier can more effectively convert the received microwave energy into available electrical energy, reduce energy loss, and improve the overall performance of the system. Summary of the Invention

[0005] The purpose of the present invention is: In order to solve the limitations and improvement requirements in the prior art, we propose a new type of broadband radio frequency rectifier. This rectifier adopts a dual-branch rectification structure, achieving high power conversion efficiency and a wide rectification bandwidth. By introducing a dual-branch rectification structure in the rectifier design and using a simple matching structure to achieve impedance matching, this design not only simplifies the circuit complexity but also increases the reliability of the rectification circuit, making it more suitable for working in a high-frequency environment and improving the overall performance.

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

[0007] A frequency-selective high-efficiency broadband radio frequency rectifier adopting a dual-branch structure, comprising: two capacitors (capacitor C1 and capacitor C2), a resistor R, four transmission lines (TL1, TL2, TL3, TL4), and two Schottky diodes (diode D1 and diode D2). It is characterized in that:

[0008] The capacitor C1 is connected in series with two parallel sub-rectification branches; the transmission lines TL3 and TL4 are connected to the common end of the capacitor C1. The other end of the transmission line TL3 is connected to the cathode of the diode D1, and one end of the transmission line TL1 is connected to the anode of the diode D1 and the other end is grounded; the transmission line TL3, the diode D1, and the transmission line TL1 together form a low-frequency band rectification branch; the other end of the transmission line TL4 is connected to the cathode of the diode D2, and one end of the transmission line TL2 is connected to the anode of the diode D2 and the other end is grounded; the transmission line TL4, the diode D2, and the transmission line TL2 together form a high-frequency band rectification branch.

[0009] Further, the frequency-selective high-efficiency broadband RF rectifier adopting a dual-branch structure is characterized in that the implementation of the frequency selection structure is composed of distributed element transmission lines TL1 and TL2. Among them, the length of transmission line TL1 is 8.2 mm and the width is 0.2 mm, the length of transmission line TL2 is 14.9 mm and the width is 0.1 mm. In addition, a square pad with a length of 0.5 mm composed of a transmission line is added on the anode side of the diode.

[0010] Further, the frequency-selective high-efficiency broadband RF rectifier adopting a dual-branch structure is characterized in that by using the dual-branch structure for design, the RF rectifier can operate with different rectification branches under different frequency bands.

[0011] Further, the frequency-selective high-efficiency broadband RF rectifier adopting a dual-branch structure is characterized in that the operating frequency band of the RF rectifier is 1.3 GHz to 3.3 GHz.

[0012] Further, the frequency-selective high-efficiency broadband RF rectifier adopting a dual-branch structure 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 1.3 GHz to 3.3 GHz.

[0013] Further, the frequency-selective high-efficiency broadband RF rectifier adopting a dual-branch structure is characterized in that when the input power of the RF rectifier is 8 dBm, the RF rectification efficiency is above 60% within the bandwidth of 1.3 GHz to 3.2 GHz.

[0014] Further, the frequency-selective high-efficiency broadband RF rectifier adopting a dual-branch structure is characterized in that when the input power of the RF rectifier is 8 dBm and at a frequency of 3 GHz, the maximum RF rectification efficiency is 71.09%.

[0015] The beneficial effects of the present invention adopting the above scheme are as follows:

[0016] By adopting the frequency selection structure of the dual-branch, the present invention effectively increases the operating bandwidth of the RF rectifier, and uses a simple matching structure to achieve impedance matching, making the RF rectification circuit more stable. In addition, this design also has significant advantages such as simple structure, compact volume, low cost, large bandwidth, and high conversion efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 is the RF circuit structure diagram of the present invention.

[0018] Figure 2 is a conversion efficiency diagram of the radio frequency rectifier in the embodiments of the present invention when the input power is 5 dBm and 8 dBm respectively. Detailed implementation manners

[0019] The present invention will be further described in conjunction with the accompanying drawings and specific implementation manners.

[0020] As Figure 1 shown, a frequency selective and highly efficient broadband radio frequency rectifier with a dual-branch structure provided in the embodiments of the present invention includes: two capacitors (capacitor C1 and capacitor C2), a resistor R, four transmission lines (TL1, TL2, TL3, TL4), and two Schottky diodes (diode D1 and diode D2). It is characterized in that:

[0021] The capacitor C1 is connected in series with two parallel sub-rectifying branches; the transmission lines TL3 and TL4 are connected to the common end of the capacitor C1, the other end of the transmission line TL3 is connected to the cathode of the diode D1, one end of the transmission line TL1 is connected to the anode of the diode D1, and the other end is grounded; the transmission lines TL3, diode D1, and transmission line TL1 together form a low-frequency band rectifying branch; the other end of the transmission line TL4 is connected to the cathode of the diode D2, one end of the transmission line TL2 is connected to the anode of the diode D2, and the other end is grounded; the transmission lines TL4, diode D2, and transmission line TL2 together form a high-frequency band rectifying branch.

[0022] For the accuracy and convenience of the implementation of the solution, further, the composition of the impedance matching network, which is composed of four transmission lines (TL1, TL2, TL3, TL4), and the length and width parameters of the transmission lines are finally determined as shown in Table 1. Table 1 Impedance matching network parameters

[0023] Further, for the frequency selective and highly efficient broadband radio frequency rectifier with a dual-branch structure, it is characterized in that: the value of the capacitor C1 is 33 pF, the dielectric constant of the used substrate is 2.65, and the thickness is 0.8 mm.

[0024] Further, after being rectified by the sub-rectifying branch and passing through the DC filtering structure, it is then connected to the load resistor R. The component parameters of the finally determined DC filter are shown in Table 2. Table 2 Component parameters of the DC filter

[0025] Further, Figure 2 shows the efficiency of this radio frequency rectifier. It can be seen from the figure that when the input power of the radio frequency rectifier is 5 dBm, the radio frequency rectification efficiency is above 50% within the bandwidth of 1.3 GHz to 3.3 GHz.

[0026] Furthermore, 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 60% within the bandwidth of 1.3 GHz to 3.2 GHz.

[0027] Brief working principle of the present invention:

[0028] In order to achieve the high efficiency and wide bandwidth performance of the RF rectifier, a frequency selection structure with a dual-branch is adopted to design the RF rectifier. The rectifier uses two sub-rectifier units, and there is no additional matching network at the input end, ensuring that the design architecture of the rectifier is simple and clear. The frequency selection structure allows the two sub-rectifier units to work together in the low-frequency and high-frequency bands, effectively increasing the working bandwidth of the RF rectifier without affecting the efficiency.

Claims

1. A frequency selective high efficiency broadband radio frequency rectifier with a dual branch structure, comprising: Two capacitors (capacitor C1 and capacitor C2), a resistor R, four transmission lines (TL1, TL2, TL3, TL4), and two Schottky diodes (diode D1 and diode D2). The invention is characterized in that: capacitor C1 is connected in series with two parallel sub-rectifier branches; transmission lines TL3 and TL4 are connected to the common end of capacitor C1, the other end of transmission line TL3 is connected to the cathode of diode D1, one end of transmission line TL1 is connected to the anode of diode D1, and the other end is grounded; transmission line TL3, diode D1 and transmission line TL1 together form a low-frequency band rectification branch; the other end of transmission line TL4 is connected to the cathode of diode D2, one end of transmission line TL2 is connected to the anode of diode D2, and the other end is grounded; transmission line TL4, diode D2 and transmission line TL2 together form a high-frequency band rectification branch.

2. The frequency selective high efficiency broadband radio frequency rectifier with a dual branch structure according to claim 1, characterized in that: The frequency selection structure is implemented using distributed element transmission lines TL1 and TL2, where the length of transmission line TL1 is 8.2 mm and the width is 0.2 mm, and the length of transmission line TL2 is 14.9 mm and the width is 0.1 mm. In addition, a square pad with a length of 0.5 mm is added on the anode side of the diode.

3. The frequency selective high efficiency broadband radio frequency rectifier with a dual branch structure according to claim 1, characterized in that: The dual-branch structure is used for design, so that the radio frequency rectifier can work by different rectifier branches in different frequency bands.

4. The frequency selective high efficiency broadband radio frequency rectifier with a dual branch structure according to claim 1, characterized in that: The operating frequency band of the RF rectifier is 1.3 GHz to 3.3 GHz.

5. The frequency selective high efficiency broadband radio frequency rectifier with a dual branch structure 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 1.3GHz to 3.3GHz.

6. The frequency selective high efficiency broadband radio frequency rectifier with a dual branch structure 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 60% within the bandwidth of 1.3GHz to 3.2GHz.

7. The frequency selective high efficiency broadband radio frequency rectifier with a dual branch structure according to claim 1, characterized in that: When the input power of the RF rectifier is 8 dBm and the frequency is 3 GHz, the maximum RF rectification efficiency is 71.09%.

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