Career Change To Electromagnetics

I am looking for information on education and opportunities and guidance in the field of electromagnetics, especially antenna engineering.

I have been working working in telecoms services- starting as a planning engineer rising to product development manager at an operator for over 15years.
I currently run my own company specializing in telecom solutions for individuals and corporates, and business is good.

However, I have always been interested in electromagnetics and have always wanted to do work in this field.
One way is to go back to school and do masters degree and possibly a PhD.

I am 40 years old now, and will be older when I finish my studies.
Will it be too late for career change?
What sort of opportunities ill I get to put into practice the newly acquired knowledge?
Should I instead do a telecoms masters and specialise in electromagnetics?
Eventually, I would like to teach when I get older

Which universities do you recommend in Europe and USA?
Given the combination of my age and absence of any experience in the field i would prefer a program that includes internship or lots of practicals