This thesis has investigated security in wireless communications at physical layer. Security is an important issue for wireless communications and poses many challenges. Most security schemes have been applied to the upper layers of communications networks. Since in a typical wireless communication, transmission of data is over the air, third party receiver(s) may have easy access to the transmitted data. This work discusses a new security technique at the physical layer for the MIMO (802.11n) transmitters. For this project, the wireless medium is secured by transmitting a noise signal that is only recoverable by the receiver. This report includes an analysis of a wireless system that shows the bit error rate (BER) of the data signal in a two dimensional map. The map is a view of the free space, which has a receiver and transmitter at the ends. This work demonstrates that the proposed security technique can significantly complement other security approaches implemented in the upper layers of the communication network. Advisers: Hamid Sharif and Michael Hempe
