SMART ANTENNAS
Hi,
first of all Smart antenna is good topic to do research no doubt about it but there is one aspect I feel always missing to the topic and it is practical implementation.If you are really interested in doing research & simulation but not practical implementation then go for it. It has large number of issues till date unsolved.
Second thing is that there is a difference in MIMO and Smart Antennas but it is better you look into IEEE A&P as well as IEEE ComSoc Digital library for some old reference papers on both of these topics.Some of the topic I find interesting are Selection of antenna in MIMOs or spectral efficiency related algorithms or ANN for Digital beamforming.
Go and search IEEE data base in above mentioned sites.
Good Luck !!