How to get MIC certification based on Realtek chipset

一、Application situation

Application	DVR
OS	Linux
Kernel version	4.15.0
WIFI interface	USB
Special Approval for WIFI function	MIC认证
The point description	DFS Master test，无法监听到雷达信号。

二、Relative preparation 

DFS（Dynamic Frequency Selection）

DFS is in order to detect the frequency of the army, then avoid to use it.

DFS scope：5250 MHz~5350 MHz,5470 MHz~ 5725MHz

DFS Master device: Radar pulse detection is required. That is to say, it must have the ability to actively detect whether there is a radar signal occupied on the working frequency, and actively select another non-occupied frequency to work

三、To collect relative certification requirement.

Reference（https://wenku.baidu.com/view/b03b26e0aeaad1f346933ff3.html）

四、 Driver debug

In driver porting, it is necessary to add relative compile condition in Makefile as following

EXTRA_CFLAGS +=-DCONFIG_DFS_MASTER  -DCONFIG_RTW_DFS_REGION_DOMAIN=3

Program  generate  8821cu.ko

五、 To finished the test with LAB and  Realtek together

First, To confirm driver is loading normally, and working in the correct frequency.

Second, The module is required to be able to detect the 103 radar types required for over detection. Register parameters need to be constantly adjusted.

Continuously modify the test according to the Realtek’s instructions. Finally confirm that all radar signals are monitored normally

cmd:

rtwpriv wlan1 write 4,19b8,00000400 –> 原值: 00001500

rtwpriv wlan1 write 4,19e4,01f54c00 –> 原值: 02f54c00

rtwpriv wlan1 write 4,19e8,2c070403 –> 原值: 22070403

Third， Upon the test result, to feedback the value has been modified to Realtek, they will patch 5.8.1.1version driver based on feedback, After detecting the signal, it actively hops the frequency. Certification finished.

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