At present, only a few high-end cars such as Mercedes-Benz have the anti-collision radar you mentioned, which has the function of automatic braking, and its main purpose is to prevent rear-end collision. This year's Auto Expo has a special test, which is an article translated from ams in Germany, but the effect is not good, so we can't rely on this equipment. There are no cars with this device in China.
However, the radar in the domestic market only has the function of prompting, and none of them has the function of automatic braking. Moreover, although it is feasible in theory, the actual operation involves driving computer, braking system and so on. It is very complicated, and even if it is available, the price will be high, not to mention the man-hour cost of installation. In addition, it is also a question whether domestic laws and regulations allow this modification.
So it is no problem to install an ordinary radar. If you want to brake automatically, don't bother.