The first round was a phone interview, behavioral round with general questions like how do you handle conflict, have you ever been in a team before and what are your strengths.
Next was a technical phone interview with questions from Maths, C/C++, Matlab and Signal Processing(Choice of 3). Math was mostly around linear algebra, matrices, eigen values, graphs, area under curves, partial fractions etc.
C/C++ was very basic programming questions like sorting and about storage class specifiers. Matlab questions can be handled with working knowledge of Matlab. Questions on what are all the 'Wh' question word commands in Matlab was asked (like who, whose). Signal processing was on filters, aliasing, Z-transforms, causality and the like.
Onsite was interview started with a much similar to this with higher complexity. Then there was a interview with the hiring manager accessing what sort of person you are, followed by lunch with two ASEs and final round with HR going over the hiring process.