I had two rounds of interview. They first explained their works. then proceeded to ask why this company and followed by tech questions. Questions were mainly from communications, linear algebra, probability and signal processing. e.g. What is vector space? if given bpsk, bfsk - what will you choose and why. compare qpsk, 4-QAM, 4psk what is pdf and cdf? how are they related. compare dtft, dtfs, ctft and ctfs.