WiFi 7 is coming? RF front-end ushered in a new opportunity!

There is no fastest, only faster. As soon as WIFI6 became popular, WIFI7 came.

Following the introduction of WIFI6 (802.11ax), a new standard of 802.11be (Extremely High Throughput) was proposed, and by analogy, the WIFI Alliance will name the 802.11be standard WIFI7.

Information technology is advancing with each passing day, benefiting mankind and suffering workers in the electronics and chip industries. But it is precisely this kind of suffering that gives us industrial workers a chance.

WIFI technology started in 1999, and it took 4 years from 802.11b to 802.11a/g. In 2009, the 802.11n WIFI standard officially started and was named WIFI4. From WIFI4 to WIFI5, it took another 4 years to open the 802.11ac standard. It took 6 years from WIFI5 to WIFI6/6E, starting the new standard 802.11ax. In 2020, the first year of WIFI6, although the 802.11be standard has been launched, the real commercialization of WIFI7 is expected to be 4-5 years later.

Source: Keysight Technologies

From the initial 1Mbps to the current 802.11ax (Wi-Fi6) peak rate of 9.6Mbps. The technical standard iteration is mainly to improve the throughput and performance of WIFI data transmission through mechanisms such as bandwidth expansion, channel coding efficiency improvement, MIMO technology, and data link layer improvement.

OFDMA multiple access technology can improve the delay problem caused by dense user access and reduce network congestion caused by channel competition mechanism. The OFDMA multiple access system divides the transmission bandwidth into a series of orthogonal non-overlapping sub-carrier sets, and allocates different sub-carrier sets to different users to achieve multiple access. The OFDMA system can dynamically allocate available bandwidth resources to users who need it, and it is easy to achieve optimal utilization of system resources. Because different users occupy non-overlapping subcarrier sets, under ideal synchronization conditions, the system has no multi-user interference, that is, no multiple access interference (MAI).

The IEEE organization has planned to conduct in-depth research on physical layers such as frequency, bandwidth, frequency band or channel aggregation based on the OFDMA multiple access mechanism of Wi-Fi 6 and other related technologies, in order to continue to improve performance, and propose a new WIFI standard. IEEE 802.11be standard.

Source: Keysight Technologies

The further you go to WIFI6 and WIFI7, the more demanding the RF front-end is.High, the requirements for the process are also higher.

　WIFI4, 802.11n:

2.4G routers have entered thousands of households, and the opportunity of RF front-end is 2.4G FEM, which is mainly due to the demand for high power. Low and medium power have been integrated. Skyworks and Qorvo have no longer updated this standard product. Early products use arsenic Gallium Process.

　WIFI5, 802.11ac:

This standard introduces the 5.8GHz band and enables 2.4G and 5.8G dual-band routers. The RF front-end opportunity has 2.4G FEM and 5.8G FEM.

2.4G FEM is added to each router at the beginning, and the output power of the RF front-end integrated in the router platform can also reach 19~20dBm, which basically does not need to be added. Skyworks offers 2.4G FEMs over GaAs and 2.4G FEMs over Silicon Germanium (SiGe) processes. Qorvo sticks to the GaAs process.

5.8G FEM, 7 years ago, Skyworks first launched 5.8G FEM with GaAs process, with an output power of [email protected] Later, I made a 5.8G FEM with a 2*2 package of silicon germanium (SiGe) process. It seems that it was unsuccessful. The cost is not bad, but the performance is worse. Qovor insists on making 5.8G FEM in GaAs process. Later, the MTK platform adopted the DPD function, and the output power of the integrated 5.8G FEM also achieved 19dBm, and there were fewer opportunities to add 5.8G FEM.

　WIFI6, 802.11ax:

2.4G FEM, Skyworks and Qorvo have all switched to silicon germanium (SiGe) process in unison, and the performance test is not bad. The best silicon germanium (SiGe) process is GF, which is also the foundry chosen by foreign manufacturers. The silicon germanium (SiGe) process has high research and development costs and is difficult to design. There are few R&D talents familiar with this process in China. The advantage is that the simulation in the design stage is relatively accurate and the production consistency is high, but the cost is similar to that of gallium arsenide. The current of the FEM developed by the silicon germanium (SiGe) process is a little better. Compared with the latest FEM of SKY, the working current of the Sanwu Micro FEM is [email protected]@DVM-43dB, while the SKY FEM works The current is [email protected]@DVM-43dB, the difference is 15mA.

5.8G FEM, Skyworks and Qorvo all use gallium arsenide process. The research and development experience of these two processes abroad is that both processes can be done, but the silicon germanium (SiGe) process is always inferior to the gallium arsenide process. A little bit. With the higher requirements for design and performance, the silicon germanium (SiGe) process becomes more and more inadequate, and the gallium arsenide process has to be adopted.

In terms of WIFI6 main chip technology, especially the underlying software protocol, there is still a gap between MTK and Qualcomm and Broadcom. The gap between domestic chip manufacturers is even greater. It is already very good that the domestic WIFI6 main chip can be mass-produced in 2 years. The advantages of MTK are also obvious, and the technology is balanced. It is very good in baseband chip, software protocol, RF transceiver, RF front-end and other technologies, especially in the world’s leading RF front-end technology.

Therefore, the MTK WIFI6 low-end solution can not use 2.4G WIFI6 FEM and 5.8G WIFI6 FEM, and the RF front-end is fully integrated to achieve power output. Qualcomm and Broadcom can’t do it, and other domestic manufacturers can’t do it.

Of course, with the arrival of WIFI6, the frequency bands of different countries have changed, and China remains unchanged, and it is estimated that it will not change in the future. But the United States and Brazil have expanded the WIFI frequency band to 7.2GHz, and Japan may follow suit. Europe raised the frequency band to 6GHz. Due to the change of the frequency band, the WIFI FEM front-end chip also needs to be changed. The higher the frequency, the wider the bandwidth, and the higher the requirements for design and process. At the same time, it is more and more difficult to integrate the RF front-end.

　WIFI7, 802.11.be:

2.4G FEM, silicon germanium (SiGe) process and gallium arsenide process will exist.

5.8G FEM, personally think it can only be GaAs process, the main chip is more difficult to integrate the RF front-end, FEM plug-in will be the mainstream.

The higher the frequency, the wider the bandwidth, and the faster the speed, the more difficult it is to develop chips, and the GaAs process is relatively advantageous, so GaAs will be the mainstream technology and future direction of WIFI FEM.

Although MTK is very powerful and continues to challenge the integrated RF front-end, the fact is that the market demand for WIFI FEM is not getting smaller and smaller, but is getting bigger and bigger. For the router market, integration will not be the mainstream. With the continuous development of WIFI technology, the market application is becoming more and more extensive, the requirements for RF front-end are getting higher and higher, and there are many opportunities for RF front-end FEM.