Summary: Lots of systems questions for a position seeking subsystem hardware design. One interviewer seemed to be seeking proprietary information. They do not honor telling you results within two weeks as they emphasize during the in-person interview and as shown on the website, and someone hung up on me after I introduced myself when I called to inquire on the status about a month after the interview. They took a lot of picture of what I wrote on the white boards. They called me about a month after I applied to the position. It was very difficult to hear them over the phone, but questions were relevant to my background and I could hear them good enough. Told me they were looking for someone who was more subsystems very hardware oriented, which matched my background although they asked a lot more systems questions during the in-person. Setting up the in person took almost a month. A person from another country tries arranging this. I ultimately settled on a day that I was not very available for, and just made it happen at my own hassle and expenses (I was local but did have to struggle with time off from work). The first part of the interview was with an HR person over the phone and they were about 10 minutes late to the call. It wasn't from the person listed in the e-mail. I was placed in a room that was scheduled for another meeting and so the people asked me to leave the room, but luckily it didn't interrupt the first call. Just a few behavioral questions and expected compensation- she sounded very skeptical when I gave her numbers, which was only a little bit higher than what I am currently making. The actual part of the interview was separated by three technical interviews with individuals and a lunch with another. The first in-person interview was the hiring manager. Asked questions about S-parameters and their transforms, transceiver design including noise figure and linearity, then questions about transmission lines, matching networks and using a Smith chart. The first person wanted to revisit our first interview after lunch, but this time we covered switched power converters, Nyquist stability contour, op-amp configurations and deriving their transfer function (buffer, subtractor, adder, inverting, non-inverting, differentiator, integrator, active filters with gain); we also talked about a few of the textbooks I read. The second in-person was during lunch time. Conversation was mostly very casual discussing some hobbies and a little about each others professional/technical background. The food was good and the person was pleasant to talk to. Third in-person was more about PCB layout and asked me about materials and their parameters such as dielectric constant and loss tangent. Process flow of the layout and rough timeline, and typical number of metal layers, how to choose a stack-up, and a few fabrication challenges/considerations such as aspect ratio. I told him I couldn't tell him exact materials I was using in fear of it being proprietary, but was okay with giving examples of well-known or common ones I've seen in textbooks, and provided an example stack-up and what my thoughts were on some design tradeoffs. Talked about the tools we were familiar with and some of their features. The last in-person asked similar question to the 1st and 3rd. I don't think English was the native language and sounded very skeptical on some of my answers. When I told them I was worried about proprietary information (seeking very specific materials, band and channel frequencies, and part numbers-- no I'm not giving that) they responded with "How could you not know? You said you designed it." Yes I did, but it belong to the company I work for. Had me do the same cascade of noise figure... after I got past the first LNA they wanted me to continue. I told them it was going to be dominated by the NF in the front and the number wouldn't change much showing the Friis formula, but they insisted that I continue (it didn't change much maybe 0.2 dB). Scoffed at some of the gain numbers I provided; they were also very disturbed by one of the filters in my design. These were confident answer as I've seen these at my current job and was straight from the textbook anyways. They told me I'd hear results within two weeks. I sent a thank you e-mail, which received no reply. Didn't hear back after two weeks. Tried calling and e-mailing after 3 weeks with no answer as I've readon on some glassdoor reviews might be the case. Fourth week I called and someone answered, but they hung up on me (I wouldn't accept an offer after that). A few days later sent an e-mail saying they'd reach out to the team to see what was going on, and that was the last I heard from them (maybe 2+ months ago?), and the position has already been taken down from the website. Please do not promise results within two weeks and hang up on me. It is okay to tell me that I did not get an offer- nothing bad will happen.