A Engineering and MBA is a good combination, however any MBA is good if you have some experience for creating better opportunities. You would use your engineering skills in the company where you work. The logical thinking, mathematical approach etc., of engineering would help in every job. I would suggest that with any of the engineering based or general administration based experience you can get in to an MBA where you can understand the potential of MBA course. This would always helps you.
Coming to Telecom Management, Telecom Management as a subject specialized for 12 year in India because the Telecom and IT sector works very closely. It’s a good course to do with lot of opportunities as the Telecom and IT sectors are growing and there is going to be a demand. Ideally I would suggest that you should be working in a Telecom company for few years before you do this course which would add value to your profile and elevation.
There are many opportunities to be in the Customer Facing, Billing, Product Development - Marketing and many other Roles in Telecom Sector. There is a growing need for development of this sector in India as the current market is very less compared to the potential. Apart from this, you need to gain some experience in the telecom field to get maximum out of your MBA and also to be placed in higher positions of the company.