I have to choose a topic for a project in my antennas class. We need to simulate an antenna so I chose spiral antennas but I just found tutorials for spiral inductors, they look the same to me, and as I am just a beginner I was wondering if someone could tell me what is the difference. And some papers or HFSS tutorials or anything relating the topic would help too.
thanks!
Yup!
When a microstrip spiral is made to be large it blurs into being a "small multi-turn loop antenna" (try searching for that instead..?) - a [generally] inefficient, narrow band structure whose radiation characteristics depends strongly on its' size, ohmic resistance etc.
Note that there is another class of spiral antennas - one where a [balanced] centre fed dipole is "wound" such that it's arms spiral radially outwards. A fascinating subset of this class is the "conical log spiral", such as described in "J. D. Dyson, The characteristics and design of the conical log-spiral antenna, IEEE Transactions on Antennas and Propagation, vol. AP-13, no. 4 July 1965, pp 488-498". This is a wideband antenna that can be formed into a cone to yield directional characteristics too.