Google Wireless Systems Engineer interview questions

First screening call with the hiring manager. Then main interviews with 4 team members. The questions were on basics of wireless communication and the whole experience was positive. But the follow up was not professional. After getting ghosted for a long time, I received the automated reply. Generally Google is known to provide some feedback/call regarding the decision, but that may not be a norm for hardware position.

I applied to this position in career portal. HR contacted me after 5 weeks. I was scheduled for 1 hour tech screen. After talking to hiring manager, i relaized this position is not related to my past experience