It was a 3 step process for me:
1. Received an initial call from senior person from Ericsson R&D Labs who discussed with me the UX opportunity.
2. This conversation was followed by a 1:1 technical interview at Ericsson office.
3. I also later had a detailed interview with R&D Head on a separate day.
4. Finally, I had a telephonic conversation with HR round and offer letter release.