CN-122026636-A - Dual-frequency radio frequency circuit based on slow wave structure

Abstract

The invention discloses a dual-frequency radio frequency circuit based on a slow wave structure, which comprises a blocking capacitor C block , a dual-frequency input impedance matching network IMN, a series microstrip line, a rectifying diode, a filter capacitor C L , a direct current load R L , a second transmission line TL2 and a first transmission line TL1, wherein 0 dBm is used as a reference input power level, and the dual-frequency rectifying circuit based on the slow wave structure provided by the invention can be used for carrying out detailed performance comparison with other designs in the prior literature, and the rectifying circuit based on the slow wave structure can show more excellent rectifying effect under 0 dBm input power. The size of the rectifying circuit is greatly reduced while the low-power high-efficiency double-frequency rectification is maintained, and the application scene of the rectifying circuit is further widened.

Inventors

• HE ZHONGQI
• HE HAOMING
• JING XIAOWEI
• SONG KAI
• LIU CHANGJUN

Assignees

• 四川大学

Dates

Publication Date

20260512

Application Date

20260410

Claims (5)

1. 1. The dual-frequency radio frequency circuit based on the slow wave structure is characterized by comprising a blocking capacitor C block , a dual-frequency input impedance matching network IMN, a series microstrip line, a rectifier diode, a filter capacitor C L , a direct current load R L , a second transmission line TL2 and a first transmission line TL1; The signal source is connected to a subsequent circuit through the blocking capacitor C block , and the blocking capacitor C block is used for isolating direct current and transmitting microwave alternating current signals; The signal source is connected in series with a dual-frequency input impedance matching network IMN to a subsequent circuit through a blocking capacitor C block , wherein the dual-frequency input impedance matching network IMN is used for realizing input impedance matching under two working frequencies, so that the impedance of the signal source is matched with the impedance of a subsequent circuit, and the transmission efficiency of microwave signals is improved; the signal source is sequentially connected with the second transmission line TL2, the rectifier diode and the first transmission line TL1 in series through the dual-frequency input impedance matching network IMN and finally grounded; The signal source is sequentially connected in series with a microstrip line and a filter capacitor C L in series through the dual-frequency input impedance matching network IMN and finally grounded, and the direct current load R L is connected in parallel with the filter capacitor C L .
2. 2. The dual-frequency radio frequency circuit based on a slow wave structure according to claim 1, wherein the first transmission line TL1 and the second transmission line TL2 are microstrip lines.
3. 3. The dual-frequency radio frequency circuit based on a slow wave structure according to claim 1, wherein the rectifier diode belongs to a schottky diode type device and is used for a microwave rectifier function.
4. 4. The slow wave structure-based dual-frequency radio frequency circuit according to claim 1, wherein the series microstrip line is a meander line structure for adjusting a microwave transmission path or for assisting in impedance transformation.
5. 5. The dual-band rf circuit of claim 1, wherein the filter capacitor C L is a filter capacitor.

Description

Dual-frequency radio frequency circuit based on slow wave structure Technical Field The invention belongs to the technical field of microwave energy application, and particularly relates to a dual-frequency radio frequency circuit based on a slow wave structure for environmental radio frequency energy recovery. Background With the rapid development of the internet of things and low-power-consumption portable equipment, a technology (radio frequency energy collection) for collecting radio frequency energy from the environment and converting the radio frequency energy into direct current electric energy has a wide application prospect. The radio frequency energy in the environment is typically spread over multiple frequency bands, such as the ISM band of 2.45 GHz and 5.8 GHz. Therefore, a rectifier circuit capable of operating efficiently at a plurality of frequency points simultaneously has been an important point of study. The conventional microstrip line dual-frequency matching network has the limitation that after the characteristic impedance and the electrical length of the microstrip line dual-frequency matching network are determined at one frequency, the parameters are fixed at other frequencies, and the linear characteristic limits the optimization of the matching performance of the microstrip line dual-frequency matching network at multiple frequency points, so that the rectification efficiency is low. Furthermore, circuit design presents a significant challenge in order to achieve high efficiency at low input power levels (e.g., 0 dBm). The existing rectifying circuit has the problems of larger circuit size, limited efficiency under low power or only being capable of working at a single frequency point. Disclosure of Invention The invention aims to overcome the defects of the prior art and provide a rectifying circuit based on a slow wave structure, which has compact structure and high double-frequency working efficiency and is particularly suitable for a low input power environment. In order to achieve the above purpose, the invention adopts the following technical scheme: A dual-frequency radio frequency circuit based on a slow wave structure comprises a blocking capacitor C block , a dual-frequency input impedance matching network IMN, a series microstrip line, a rectifier diode, a filter capacitor C L, a direct current load R L, a second transmission line TL2 and a first transmission line TL1; The signal source is connected to a subsequent circuit through the blocking capacitor C block, and the blocking capacitor C block is used for isolating direct current and transmitting microwave alternating current signals; the signal source is connected in series with a dual-frequency input impedance matching network IMN to a subsequent circuit through a blocking capacitor C block, wherein the dual-frequency input impedance matching network IMN is used for realizing input impedance matching under two working frequencies so as to enable the signal source to be in impedance adaptation with a subsequent circuit and improve the transmission efficiency of microwave signals; the signal source is sequentially connected with the second transmission line TL2, the rectifier diode and the first transmission line TL1 in series through the dual-frequency input impedance matching network IMN and finally grounded; The signal source is sequentially connected in series with a microstrip line and a filter capacitor C L in series through the dual-frequency input impedance matching network IMN and finally grounded, the direct current load R L is connected in parallel with the filter capacitor C L, wherein the direct current load R L is a pure resistive load and has stable characteristics, the length/impedance of the transmission line is adjusted through the microstrip line connected in series and the matching of the filter capacitor C L is adjusted, a stable load impedance reference is provided for one or two working frequencies, the dual-frequency matching network can simultaneously meet impedance matching conditions under two frequencies, and the microwave power transmission efficiency is maximized. The direct current load R L is connected with the filter capacitor C L in parallel, and the path is a key auxiliary unit for realizing double-frequency impedance matching and stable signal processing of the double-frequency microwave circuit, namely, the double-frequency impedance matching network is assisted by a pure-impedance load to complete impedance adaptation, reasonable distribution and absorption of signal energy are realized, and efficient and stable work of a main path device (SMS 7630) is ensured. Further, the first transmission line TL1 and the second transmission line TL2 are microstrip line structures. Furthermore, the rectifier diode belongs to a schottky diode device and is used for a microwave rectification function. Further, the series microstrip line has a meander line structure, and is used for adjusting a