Microwave Tech - 5g front end RF Technology

With the opening of 5G era, network base stations and user equipment (such as mobile phones) become more and more slim and compact, and the energy consumption is also becoming lower and lower. Printed circuit board (PCB) used in many RF applications are also being downsized to fit smaller devices. A typical RF front-end consists of switch, filter, amplifier and tuning components. In 5g applications such as mobile phone, small cell, antenna array system and Wi Fi, RF front-end is becoming a complex and highly integrated system packet.

As the core component, what are the technical improvements of RF front-end module?

1. Gan technology

Gallium nitride (GAN) is a kind of binary III / V band gap semiconductor, which is very suitable for high power and high temperature resistant transistors.

Some important properties of gallium technology are as follows:

Reliability and robustness: gallium nitride has higher power efficiency and therefore lower heat output. Using gallium nitride can eliminate these high-cost heat dissipation methods.

Low current consumption: gallium nitride reduces operating costs and generates less heat. In addition, low current also helps to reduce system power consumption and power requirements.

Power capability: Gan devices provide higher output power than other semiconductor technologies.

Frequency bandwidth: gallium nitride has high impedance and low gate capacitance, which can achieve larger working bandwidth and higher data transmission speed.

Integration: 5G requires a smaller solution, which has prompted suppliers to replace large-scale, multi technology, discrete RF front-end with single, fully integrated solutions.

2. Bulk acoustic wave filter technology

Surface acoustic wave (SAW) filter and bulk acoustic wave filter (BAF) have the advantages of small occupied area, excellent performance, economic applicability and so on.

The bulk acoustic wave filter is most suitable for the frequency band from 1 GHz to 6 GHz, and the surface acoustic wave filter is most suitable for the frequency band below 1 GHz.

For smart phone designers, 5G is a challenge for battery life and motherboard space.

Not surprisingly, from 4G to 5G, the number of filters installed in mobile phones has increased dramatically, and carrier aggregation is the main factor contributing to the increase.

3. RF technology, package and design

The RF front-end consists of several semiconductor technology devices. Many 5G applications need a variety of processing techniques, design techniques, integration methods and packaging methods to meet the needs of each unique use case.

For 5G band below 7GHz, the corresponding RF front-end solutions need innovative packaging methods, such as improving the compactness of component arrangement, shortening the wire length between components to minimize loss, adopting double-sided installation, zoning shielding, and using higher quality surface mount technology components.

All 5G use cases require RF front-end technology. According to the performance requirements of RF function, frequency band and power level, the selection of RF semiconductor technology is different.