CN-122026830-A - Ultra-bandwidth impedance matching circuit structure

Abstract

The invention discloses an ultra-bandwidth impedance matching circuit structure, which relates to the technical field of radio frequency microwave integrated circuits and comprises a first transmission line, a second transmission line, a third transmission line and a fourth transmission line, wherein the starting end of the first transmission line and the starting end of the third transmission line are connected with a signal source input end, the ending end of the third transmission line is connected with a load end, the ending end of the second transmission line and the ending end of the fourth transmission line are connected with the signal source input end and the starting ends of the first transmission line and the third transmission line, and the starting ends of the second transmission line and the fourth transmission line are connected with a signal ground.

Inventors

• ZHANG ZONGNAN

Assignees

• 张宗楠

Dates

Publication Date

20260512

Application Date

20260305

Claims (8)

1. 1. An ultra-bandwidth impedance matching circuit structure, comprising: A first transmission line, a second transmission line, a third transmission line, and a fourth transmission line; the starting end of the first transmission line and the starting end of the third transmission line are connected with the signal source input end, and the ending end of the first transmission line and the third transmission line are connected with the load end; the termination ends of the second transmission line and the fourth transmission line are connected with the signal source input end and the starting ends of the first transmission line and the third transmission line; the starting ends of the second transmission line and the fourth transmission line are connected with signal ground; the first transmission line and the third transmission line have the same current direction, and the second transmission line and the fourth transmission line have the same current direction and are opposite to the current directions of the first transmission line and the third transmission line; the four transmission lines are arranged in parallel or in cross coupling at a certain interval, and the distributed capacitance and the distributed inductance between the transmission lines jointly form an artificial transmission line structure.
2. 2. The ultra-wideband impedance matching circuit of claim 1, wherein the input voltage Vin, input current 2I, load voltage VL, load current I of the matching circuit satisfy the following relationship: Wherein the method comprises the steps of All are signal source impedances, and thus the impedance transformation ratio is obtained as follows: i.e. a typical impedance transformation ratio of 1:4.
3. 3. The ultra-wideband impedance matching circuit of claim 2, wherein the matching network has minimal transmission loss when the transmission line characteristic impedance Z0 satisfies the relationship: 。
4. 4. the ultra-wideband impedance matching circuit structure of claim 1, wherein said transmission line trace has a square, circular or octagonal shape.
5. 5. The ultra-wideband impedance matching circuit structure of claim 1, wherein said transmission lines are coupled by upper and lower metal layers.
6. 6. The ultra-bandwidth impedance matching circuit structure according to claim 1, wherein the four transmission lines have the same widths and the same characteristic impedance Z0.
7. 7. An ultrabandwidth impedance matching circuit structure as recited in claim 2, wherein the impedance transformation ratio is adjusted by adjusting the characteristic impedance of the transmission line to adapt to different source and load impedances.
8. 8. The ultra-bandwidth impedance matching circuit structure according to claim 1, wherein the matching circuit is connected to the output end of the power amplifier, the output end is provided with a blocking capacitor, and the power supply end is directly connected to VDD without adding a choke inductance.

Description

Ultra-bandwidth impedance matching circuit structure Technical Field The invention relates to the technical field of radio frequency microwave integrated circuits, in particular to an ultra-bandwidth impedance matching circuit structure. Background In a wireless communication system, a power amplifier is a transmitter core module whose performance is determined by transistors in combination with matching circuitry. Since the optimal load impedance of the transistor does not match the antenna port impedance (typically 50Ω), the matching circuit must be designed for impedance transformation. Conventional matching circuits, such as multi-stage LC matching networks or stepped impedance transformers, have problems of large loss, large size, low integration, etc. in ultra-wideband applications. The multi-stage matching network needs multiple sections of elements, so that loss is increased, the stepped impedance converter needs long transmission lines at low frequency band, needs wide line width at low impedance, and is difficult to integrate on-chip. Therefore, there is a need for an impedance matching circuit that combines ultra-wideband, low loss, and small size. Disclosure of Invention Aiming at the defects of the prior art, the invention provides an ultra-bandwidth impedance matching circuit structure, which solves the problems proposed by the background technology. In order to achieve the above purpose, the invention is realized by the following technical scheme that the ultra-bandwidth impedance matching circuit structure comprises: a first transmission line (Tline 1), a second transmission line (Tline 2), a third transmission line (Tline 3), and a fourth transmission line (Tline 4); The first transmission line (Tline 1) and the third transmission line (Tline 3) are connected with the signal source input end and the load end; The termination ends of the second transmission line (Tline 2) and the fourth transmission line (Tline 4) are connected with the signal source input end and the starting ends of the first transmission line (Tline 1) and the third transmission line (Tline 3); The starting ends of the second transmission line (Tline 2) and the fourth transmission line (Tline 4) are connected with signal ground; The first transmission line (Tline 1) and the third transmission line (Tline 3) have the same current direction, and the second transmission line (Tline 2) and the fourth transmission line (Tline 4) have the same current direction and are opposite to the current directions of the first transmission line and the third transmission line; the four transmission lines are arranged in parallel or in cross coupling at a certain interval (d), and the distributed capacitance and the distributed inductance between the transmission lines jointly form a manual transmission line structure. As a further technical scheme of the invention, the input voltage Vin, the input current 2I, the load voltage VL and the load current I of the matching circuit satisfy the following relationships: Wherein the method comprises the steps of All are signal source impedances, and thus the impedance transformation ratio is obtained as follows: i.e. a typical impedance transformation ratio of 1:4. As a further technical solution of the present invention, the matching network has a minimum transmission loss when the transmission line characteristic impedance Z0 satisfies the following relationship:。 as a further technical scheme of the invention, the transmission line is square, round, octagonal and the like. As a further technical scheme of the invention, the coupling mode between the transmission lines is upper and lower metal coupling. As a further technical scheme of the present invention, the widths (w) of the four transmission lines are the same, and have the same characteristic impedance Z0. As a further technical solution of the present invention, the impedance transformation ratio is adjusted by adjusting the characteristic impedance of the transmission line, so as to adapt to different source impedance and load impedance. As a further technical scheme of the invention, the matching circuit is connected with the output end of the power amplifier, the output end is provided with the blocking capacitor, and the power supply end is directly connected with the VDD without adding a choke inductance. The invention provides an ultra-bandwidth impedance matching circuit structure, which has the following beneficial effects compared with the prior art: 1. Ultra-wideband response, namely converting parasitic parameters into matching conditions through a manual transmission line structure to realize 4-13 GHz broadband matching; 2. Low loss, no multi-stage LC element is needed, and energy loss is reduced; 3. the small size is that long transmission lines or wide line width are not needed, and the method is suitable for MMIC integration; 4. the high integration level can be directly integrated with a power amplifier without additional