I applied online, passed the phone interview which was not very technical. The on-site interview had 7 rounds. They ask me a lot about ARM processor architecture and C++ questions.

Very detail on fundamental knowledge of communication, signal processing. I was asked to write down equations and deduction on blackboard. Most asked questions based on projects on your resume, and extend to the whole system coverage. E.g., if you said you have work on AGC, you could be asked about LNA gain, SNRQ, ADC, quantization noise, DVGA, set point etc., and relations among them.