CN103311627A - P-waveband lumped-type miniature balun - Google Patents

Abstract

The invention discloses a P-band lumped miniature balun, which includes an input/output interface mounted on a surface, and a low-pass filter and a high-pass filter combined by capacitance and inductance using lumped elements, and further combined into a balanced-unbalanced converter. The invention has the advantages of small area, small volume, light weight, high reliability, excellent electrical performance, good temperature stability, good batch consistency of electrical performance indicators, low mass production cost, etc., and is especially suitable for communication in the corresponding microwave frequency band , digital radar, individual satellite mobile, military and civilian multi-mode and multi-channel communication system terminals, wireless communication handheld terminals, etc., as well as corresponding systems that have strict requirements on volume, weight, performance, and reliability.

Description

P-Band Lumped Miniature Balun

technical field

The present invention relates to a balun, especially a P-band lumped miniature balun.

Background technique

技术采用多层立体三维集成技术，使射频无源器件小型化、高性能、低成本成为可能。在现代通信技术日益小型化的趋势下，巴伦作为天线的馈电网络和相移器、平衡放大器、相位检波器、平衡混频器等微波技术的关键器件之一，应用非常广泛，其性能优劣往往直接影响整个通信系统的性能指标。描述这种部件性能的主要技术指标有：工作频率、带宽、回波损耗、插入损耗、幅度不平衡性、相位不平衡性、体积、重量、可靠性等。在追求器件小型化的同时为了降低其损耗，获得更高的品质因数，就需要寻求新的材料和技术。微波集成电路中的无源元件巴伦大多采用微带线构成。和其他结构相比，微带线可近似为准TEM波传输，分析比较简单方便，而且封装尺寸较小。 With the increasing popularity of wireless communication and personal wireless electronic terminal products, the goals of excellent performance, small size, low cost and high reliability have attracted more and more people's attention and pursuit, especially the miniaturization of devices has become the frontier and hot spot of research. advanced

The technology adopts multi-layer three-dimensional three-dimensional integration technology, which makes it possible for radio frequency passive devices to be miniaturized, high-performance, and low-cost. Under the trend of miniaturization of modern communication technology, balun is widely used as one of the key components of microwave technology such as antenna feed network and phase shifter, balanced amplifier, phase detector, and balanced mixer. Pros and cons often directly affect the performance indicators of the entire communication system. The main technical indicators describing the performance of this component are: operating frequency, bandwidth, return loss, insertion loss, amplitude imbalance, phase imbalance, volume, weight, reliability, etc. In pursuit of device miniaturization, in order to reduce its loss and obtain a higher quality factor, it is necessary to seek new materials and technologies. Most of the passive component baluns in microwave integrated circuits are composed of microstrip lines. Compared with other structures, the microstrip line can be approximated as quasi-TEM wave transmission, the analysis is relatively simple and convenient, and the package size is small.

Contents of the invention

The purpose of the present invention is to provide a P-band lumped miniature balun with small volume, light weight, high reliability, stable temperature performance, excellent electrical performance, good batch electrical performance consistency, and low cost.

The technical solution for realizing the purpose of the present invention is: a P-band lumped miniature balun, characterized in that: it includes a surface-mounted 50-ohm impedance input port, a third-order low-pass prototype circuit, a third-order high-pass prototype circuit, and a surface-mounted 50 ohm impedance first output port, surface mount 50 ohm impedance second output port and ground terminal; surface mount 50 ohm impedance input port has one end connected to the input signal, and the other end is respectively connected to the first inductance in the third-order low-pass prototype circuit One end, the common terminal of the third inductor and the second capacitor in the third-order high-pass prototype circuit are connected; the third-order low-pass prototype circuit is composed of the first inductor, the first capacitor and the second inductor, wherein the first inductor and the second inductor The common terminal is connected to one end of the first capacitor; the third-order high-pass prototype circuit is composed of the third inductor, the second capacitor and the fourth inductor; the other end of the second inductor in the third-order low-pass prototype circuit is connected to one end of the first output port , the other end of the first output port is connected to the output signal; the common end of the fourth inductor and the second capacitor in the third-order high-pass prototype is connected to one end of the second output port, and the other end of the second output port is connected to the output signal; the third-order low-pass The other ends of the first capacitor of the pass prototype, the third inductor of the third-order high-pass prototype, and the fourth inductor are respectively grounded.

Compared with the prior art, the present invention has the following significant advantages: (1) The 430 MHz P-band lumped miniature balun of the present invention utilizes the characteristics of multi-layer low-temperature co-fired ceramic technology (LTCC), and adopts a three-dimensional multi-layer laminated structure to realize the circuit (2) Using the high dielectric constant of LTCC ceramics can also greatly reduce the size of components; (3) Using the low loss characteristics of LTCC materials and unique circuit structure to achieve excellent electrical performance; (4) Utilizing the high temperature stability and reliability of low-temperature ceramic materials, the components have high temperature stability and high reliability; (5) Utilizing the consistency of mass production of the LTCC process to obtain high yield and low cost. In a word, the present invention has small size, light weight, high reliability, excellent electrical properties, high temperature stability of electrical properties, simple circuit structure, and good consistency of electrical properties. It can be installed and welded by automatic placement machines, and is especially suitable It is suitable for communication in the corresponding microwave frequency band, digital radar, individual satellite mobile, military and civilian multi-mode and multi-channel communication system terminals, wireless communication handheld terminals, etc., as well as corresponding systems that have strict requirements on volume, weight, performance, and reliability. .

Description of drawings

Fig. 1 is the electrical schematic diagram of the P-band lumped miniature balun of the present invention.

Fig. 2 is a schematic diagram of the appearance and internal structure of the P-band lumped miniature balun of the present invention.

Fig. 3 is the S parameter simulation result of the P band lumped miniature balun of the present invention

Fig. 4 is the amplitude unbalance curve of the balanced output port of the P-band lumped miniature balun of the present invention.

Fig. 5 is the phase unbalance curve of the balanced output port of the P-band lumped miniature balun of the present invention.

Detailed ways

The present invention will be described in further detail below in conjunction with the accompanying drawings.

1, the present invention is a P-band lumped miniature balun, which includes a surface-mounted 50-ohm impedance input port P1, a third-order low-pass prototype circuit L1C1L2, a third-order high-pass prototype circuit L3C2L4, and a surface-mounted 50-ohm impedance first output port P2, surface-mounted 50-ohm impedance second output port P3 and ground terminal; surface-mounted 50-ohm impedance input port P1 has one end connected to the input signal, and the other end is respectively connected to the third-order low-pass prototype circuit L1C1L2 One end of the first inductance L1, the third inductance L3 in the third-order high-pass prototype circuit L3C2L4 and the common end of the second capacitor C2 are connected; the third-order low-pass prototype circuit L1C1L2 is composed of the first inductance L1, the first capacitor C1 and the second inductance Composed of L2, wherein the common end of the first inductance L1 and the second inductance L2 is connected to one end of the first capacitor C1; the third-order high-pass prototype circuit L3C2L4 is composed of the third inductance L3, the second capacitor C2 and the fourth inductance L4; the third-order The other end of the second inductor L2 in the low-pass prototype circuit is connected to one end of the first output port P2, and the other end of the first output port P2 is connected to the output signal; in the third-order high-pass prototype, the common terminal is connected to one end of the second output port P3, and the other end of the second output port P3 is connected to the output signal; the other end of the first capacitor C1 of the third-order low-pass prototype, the third inductor L3 of the third-order high-pass prototype, and the fourth inductor L4 One end is grounded respectively.

In conjunction with Fig. 2, the P-band lumped miniature balun of the present invention, the input port P1, the third-order low-pass prototype L1C1L2, the third-order high-pass prototype L3C2L4, the first output port P2, the second output port P3 and the ground terminal all adopt multi-layer The low-temperature co-fired ceramic process is realized, in which the first inductor L1 and the second inductor L2 of the third-order low-pass prototype L1C1L2 and the third inductor L3 and fourth inductor L4 of the third-order high-pass prototype L3C2L4 adopt multi-layer coupled striplines in a ring The first capacitor C1 of the third-order low-pass prototype L1C1L2 and the second capacitor C2 of the third-order high-pass prototype L3C2L4 are all realized by dielectric plate capacitors.

The P-band lumped miniature balun of the present invention is characterized in that: the first inductance L1 and the second inductance L2 of the third-order low-pass prototype L1C1L2 and the third inductance L3 and the fourth inductance L4 of the third-order high-pass prototype L3C2L4 all adopt integrated The total parameter multi-layer coupled stripline structure is realized; the first capacitor C1 of the third-order low-pass prototype L1C1L2, and the second capacitor C2 of the third-order high-pass prototype L3C2L4 are realized by a two-layer coupled stripline structure with lumped parameters; the third-order The first inductor L1 of the low-pass prototype L1C1L2 is connected to the common terminal of the first capacitor C1 and the second inductor L2, and the two ends of the second capacitor C2 of the third-order high-pass prototype L3C2L4 are respectively connected to the third inductor L3 of the third-order high-pass prototype L3C2L4 , one end of the fourth inductor L4 are connected, and the other ends of the first capacitor C1 of the third-order low-pass prototype L1C1L2, the third inductor L3 and the fourth inductor L4 of the third-order high-pass prototype L3C2L4 are respectively grounded.

The working principle of the P-band lumped miniature balun of the present invention is briefly described as follows: the input broadband microwave signal is divided into two signals through the unbalanced input port (P1), and one signal reaches the third-order low-pass prototype circuit (L1, C1 , L2) one end of the first inductor (L1), through the first inductor (L1), the passband signal of the second inductor (L2) reaches the balanced output port (P2), and the non-passband signal passes through the first capacitor (C1 ) to ground for low-pass filtering and a phase shift lag of 90 degrees. The other signal arrives at the common end of the third inductor (L3) and the second capacitor (C2) of the third-order high-pass prototype circuit (L3, C2, L4), respectively passes through the third inductor (L3) to ground, passes through the second capacitor (C2) ) pass-band signal reaches the balanced output port (P3), while the non-pass-band signal is grounded through the fourth inductor (L4) to achieve high-pass filtering and a phase shift ahead of 90 degrees. This realizes splitting a single-ended unbalanced input signal into two equal-amplitude and inverted balanced output signals. On the one hand, it can play the role of impedance transformation, on the other hand, the two outputs have a phase difference of 180 degrees, which is equivalent to a power divider with output reverse function.

The P-band lumped miniature balun is realized by the multi-layer low-temperature co-fired ceramic process, and its low-temperature co-fired ceramic material and metal pattern are sintered at a temperature of about 900 ° C, so it has very high reliability and temperature stability. , because the structure adopts three-dimensional integration and multi-layer folding structure, and the metal shielding on the outer surface realizes grounding and packaging, so that the volume is greatly reduced. The balun implementation volume is 4.5mm×3.2mm×1.6mm. The center frequency is 430MHz, the bandwidth is 60MHz, the simulated balun is within the passband range, and the amplitude imbalance of the balanced port is less than 0.4dB. The return loss S11 is greater than 14dB. In the passband range, the phases of the two balanced ports change linearly, the phase difference is close to 180°, and the phase imbalance is less than 0.1°.

Claims (3)

1. A P-band lumped miniature balun is characterized in that: a 50-ohm impedance input port (P1), a third-order low-pass prototype circuit (L1, C1, L2) and a third-order high-pass prototype circuit ( L3, C2, L4), surface mount 50 ohm impedance first output port (P2), surface mount 50 ohm impedance second output port (P3) and ground terminal; surface mount 50 ohm impedance input port (P1) one end Connect to the input signal, and the other end is respectively connected to one end of the first inductor (L1) in the third-order low-pass prototype circuit (L1, C1, L2), and the third inductor (L3) in the third-order high-pass prototype circuit (L3, C2, L4). Connected to the common terminal of the second capacitor (C2); the third-order low-pass prototype circuit (L1, C1, L2) is composed of the first inductor (L1), the first capacitor (C1) and the second inductor (L2), where The common terminal of the first inductor (L1) and the second inductor (L2) is connected to one end of the first capacitor (C1); the third-order high-pass prototype circuit (L3, C2, L4) is composed of the third inductor (L3), the second capacitor (C2) and the fourth inductor (L4); the other end of the second inductor (L2) in the three-order low-pass prototype circuit is connected to one end of the first output port (P2), and the other end of the first output port (P2) Connect to the output signal; the common end of the fourth inductor (L4) and the second capacitor (C2) in the three-order high-pass prototype is connected to one end of the second output port (P3), and the other end of the second output port (P3) is connected to the output signal ; The other ends of the first capacitor (C1) of the third-order low-pass prototype, the third inductor (L3) and the fourth inductor (L4) of the third-order high-pass prototype are respectively grounded. 2. The P-band lumped miniature balun according to claim 1, characterized in that: input port (P1), third-order low-pass prototype (L1, C1, L2), third-order high-pass prototype (L3, C2, L4), the first output port (P2), the second output port (P3) and the ground terminal are all realized by multi-layer low-temperature co-fired ceramic technology, in which the first inductor of the third-order low-pass prototype (L1, C1, L2) ( L1), the second inductor (L2) and the third inductor (L3) and fourth inductor (L4) of the third-order Qualcomm prototype (L3, C2, L4) are wound in a circular manner using multilayer coupled striplines , the layers are connected by circular vias; the first capacitor (C1) of the third-order low-pass prototype (L1, C1, L2) and the second capacitor (C2) of the third-order high-pass prototype (L3, C2, L4) are used Dielectric plate capacitors are realized. 3. The P-band lumped miniature balun according to claim 1, characterized in that: the first inductance (L1), the second inductance (L2) and the third-order low-pass prototype (L1, C1, L2) The third inductance (L3) and the fourth inductance (L4) of the first-order high-pass prototype (L3, C2, L4) are realized by the lumped parameter multilayer coupled stripline structure; the third-order low-pass prototype (L1, C1, L2) The first capacitor (C1) of the third-order high-pass prototype (L3, C2, L4) and the second capacitor (C2) of the third-order high-pass prototype (L3, C2, L4) are realized by a two-layer coupled stripline structure with lumped parameters; the third-order low-pass prototype (L1, C1 , L2) the first inductor (L1) is connected to the common terminal of the first capacitor (C1) and the second inductor (L2), the two of the second capacitor (C2) of the third-order high-pass prototype (L3, C2, L4) The terminals are respectively connected to one end of the third inductor (L3) and the fourth inductor (L4) of the third-order high-pass prototype (L3, C2, L4), and the first capacitor of the third-order low-pass prototype (L1, C1, L2) ( C1), the other end of the third inductor (L3) and the fourth inductor (L4) of the third-order high-pass prototype (L3, C2, L4) are respectively grounded.

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