Electric control impedance deploying chip based on radio frequency micro electro mechanical structure and microwave system

Abstract

The invention discloses an electric control impedance deploying chip based on a radio frequency micro electro mechanical system (RF-MEMS) structure. The electric control impedance deploying chip comprises a chip substrate and an MEMS impedance deployer, and is characterized in that the MEMS impedance deployer is designed and manufactured on the chip substrate; the MEMS impedance tuner comprises amotor type impedance tuner or a switch type impedance tuner; the motor type impedance tuner comprises a micro electro mechanical device and a central conductor; the micro electro mechanical device comprises a micro motor with a radio frequency micro electro mechanical structure and a microwave probe; and the micro motor drives the microwave probe to move in the axial direction of the central conductor or in the vertical direction of the central conductor. The invention further provides an electronic control impedance deploying microwave system based on the radio frequency micro electro mechanical system structure. A typical application case comprises a power amplifier and a receiving and transmitting module. Due to the design, the integration and miniaturization of the microwave system with the impedance tuner structure are realized, and the working bandwidth and multi-channel adaptability of the MEMS impedance tuner system are improved, and the reliability of a working temperature zone is enhanced.

Description

technical field [0001] The invention relates to the field of electronic components, in particular to an electronically controlled impedance adjustment chip and a microwave system based on a radio frequency micro-electromechanical structure. Background technique [0002] Impedance adjuster is an important device in high-power microwave application system. There are two schemes for the impedance adjuster implemented in the prior art: one is an electronically controlled impedance adjuster based on a mechanical structure, and the other is an impedance adjuster based on adjustable discrete components such as inductors, capacitors, and resistors. [0003] The electronically controlled impedance adjuster based on the mechanical structure uses a mechanical motor to drive the probe for impedance adjustment, and the impedance adjuster based on adjustable discrete components such as inductors, capacitors, and resistors realizes impedance by adjusting the values ​​of the inductance, cap...

AI Technical Summary

Problems solved by technology

Due to the use of mechanical motors, regular maintenance is required, the reliability is poor, and it cannot meet the requirements of unattended working conditions and high reliability applications

[0005] 2. Harmonic impedance adjustment is difficult to realize, and the volume and weight will further increase

Multiple motors and impedance adjustment probes further increase the complexity of volume, weight, control and measurement software, and further reduce reliability

In terms of distance, the 3rd harmonic impedance adjuster requires 3 mechanical motors to be coordinated, which increases the weight by more than 30%, and the reliability is greatly reduced

[0006] 3. Impedance adjustment accuracy is not high

Discrete components such as adjustable inductors, capacitors, and resistors usually work in the nonlinear region. The electrical properties of the components change nonlinearly with the control voltage, and the changes are sensitive and temperature-dependent, making it difficult to achieve high-precision and stable deployment.

[0007] 4. The scope of impedance adjustment is limited, it is difficult to achieve phase shift, especially the application that requires real delay is difficult to meet

Adjustable discrete components such as inductors, capacitors, and resistors can produce phase shifts within a certain range, but they are not real phase shift devices after all, and it is difficult to meet the needs of some real delay measurement applications.

[0008] 5. Insufficient efficiency optimization ability, difficult to work stably

When applied in the design of high-efficiency power amplifiers, there is often the problem of insufficient impedance adjustment range, which requires a multi-stage impedance adjustment network to achieve, which will lead to increased return loss, insertion loss and other losses, which restricts the improvement of efficiency.

Discrete components such as adjustable inductors, capacitors, and resistors usually work in the nonlinear region. The electrical properties of the components change nonlinearly with the control voltage, and the changes are sensitive and temperature-dependent, making it difficult to achieve high-precision and stable deployment.

Therefore, the precision of impedance adjustment based on the existing discrete component technology is not high, and it is difficult to work stably

High-efficiency power amplifiers are usually used in 4G / 5G mobile phone base stations, aerospace and other occasions that require wide temperature and long-term stable work. High-efficiency power amplifiers such as Doherty with existing technologies are often difficult to meet standards in terms of stability and reliability.

[0009] 6. The performance of millimeter wave is not good, and the working bandwidth is narrow, which is limited to low frequency applications

High-efficiency power amplifiers such as Doherty realized by the existing technology are usually realized by 1 / 4 wavelength transmission line. This technology is only effective for one frequency point, and it is difficult to achieve broadband operation.

Existing discrete component technology, due to the frequency band limitation of adjustable inductors, capacitors, resistors and other discrete components, electronically controlled adjustable impedance matching usually works within 2GHz, which is difficult to meet the needs of high-frequency applications above 2GHz

[0010] 7. Difficult to integrate in microwave power amplifier and communication system

For example, the Doherty power amplifier needs to adjust the load impedance to obtain high efficiency, but because the mechanical impedance adjuster is too large, it is difficult to integrate in the product and power amplifier module, and can only be used during debugging and testing

For another example, in transceiver (T / R) devices and phased array systems, it is necessary to adjust the reflection coefficient, impedance, and phase difference of each channel, but because the mechanical impedance adjuster is too large, it is difficult to integrate it at the module and system level in production and should only be used during commissioning and testing

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