Omar, Seems like you are in a very similar boat as mine. I have a BS and MS in EE from one of the top 50 schools with average GPAs and no significant research experience. I have been with Honeywell Aerospace for 5.5 years and now considering PhD in EE/Aero E.
Unless you have had some specific projects at work which would relate with the faculty research, I think, without research, it is very difficult to get faculty attention from top schools. Doesn’t hurt to try but I would definitely keep the options open? Given your high MS GPA I think it is easy to overlook your undergrad GPA so you should be fine there.
DSP is a good area as there are quite a few EE professors in every school increasing your chances of getting picked. I am into Control Systems and it is only a handful profs at any uni…L
Good luck
Ali