激动:
1. excited, including the mood of being happy and moved. when u win a prize, award, u are 激动的
2. nervous. when u see your dream lover, u are too 激动 to speak out.
兴奋:if u are 兴奋,u are too energetic to sleep, stop walking or dancing, maybe because u are too happy or excited, or a result of some drug. for instance, 兴奋剂 is a kind of drug which lead to 兴奋。
亢奋 is a derogatory term, it is over 兴奋,may be some kind of disease. it may also be the result of drug.