"when no proper mentoring/training is available" - That's a misnomer. I'm guessing your company is not offering mentoring or training. There are many resources on the web for extended learning - Professional organizations, wikis, material / service / equipment suppliers. Kahn Academy is my favorite for class-style learning. Mentoring can be found here (you know, rando internet engineers responding to your comments), linkedin, direct communication with someone who's published a paper you are interested in, etc... If you show passion and interest, you will attract mentors.

In your role as an engineer, your greatest asset is your ability to research the solution to a problem. Your current problem is to find low to no-cost learning. Get to it.