The feedback I got in respect with this issue is that RADAR SDK is available based on request for evaluation.
Once you have logged in into your NXP account you will need to add a Support Request:
Once the request is approved you should be able to see the package available for download in your software account.
Hope this helps!
PS: where are you from ? China ?
I might be able to put you in contact with a representative familiar with the topic.
thanks for your interest in the Radar SDK. A code or link will be generated to grant you access to the relevant software package. I will take the appropriate actions for it.