Siemens Engineer interview questions

there was a written test coupled with group discussion. these were some of the technical quesions written test contain apti and tech both. 25 que on tech and 25 que on apti. no negative marking. 1) what is the radiation pattern of hertizian dipole perpendicular to the plane of the dipole? 2)que for calculating VSWR. 3)full form of VIRUS. 4)what is the purpose of duplexer in radar. 5)que of xnor gate. 6)prinicipal of zener diode. que asked from every subject but 3-4 que from antenna.

I applied in Siemens VAI. After 4 to 5 months i was called for interview in hotel Vatsa in bhilai as siemens VAI is looking after an project in bhilai steel plant. so they are having their city office in the same hotel where i was called for the interview. my interview went for around 1 hour and finally after 1 month i was asked to join the company.