First, HR phone interview. It was very simple. Just some behavioral questions. Then they gave me a technical phone interview. It lasted about 1 hour. The interviewer was keeping asking questions one by one. However, all the questions are very basic but detailed. 1. DSP: 1) What is IIR and FIR? Difference? Given an example to judge whether it s IIR or FIR and why? 2) What is z-transform? She gave me a sequence and asked me to get its z-transform 3) Given a sequence, judged whether it is stable or not. Why? 4) What is the relation between the unit circle and stable? 5) I do not remember other questions, sorry! 2. Math: 1) Calculate the eigenvalue and eigenvector of a given 2-by-2 matrix. 2) Calculate the inverse of a given 2*2 matrix. 3) What is the null space of a given matrix. 4) I do not remember other questions, sorry! 3. C: 1) What is pointer? 2) What is typedef used for? 3) What is the difference between malloc and new? 4. Matlab: 1) How to merge two strings? 2) What is the difference between function and script? 3) How to access the variable hide in a function? Good luck!