"Multi-carrier (MC) transmission, in particular orthogonal frequency division multiplexing (OFDM), is employed in various systems mainly due to its robustness. In particular, with the deployment of WiMAX (and the upcoming LTE) systems, research in OFDM hastened. In OFDM systems, smart antenna systems with multiple transmit and receive antennae and location estimation are likely to be an area of interest. In recent years, adaptive antennae and array processing greatly impacted the performance of wireless communication systems. Also, location based services are gaining importance everyday increasing the need for better location estimation algorithms. In this work, we propose to investigate one of the most essential issues of adaptive antenna systems: the estimation of angles of arrival (AOA) for OFDM systems and its utilization in location estimation and development of location based services. The main advantage for location estimation using angles compared to distance (timing advance) is that instead of three reference points, only two reference points are sufficient. In our work, we propose to use basis selection (BS) algorithms, namely the matching pursuit (MP) algorithms for AOA and location estimation, by exploiting the sparsity property of AOA for OFDM. The main advantages of applying BS algorithms to this estimation problem are the decreased complexity and increased resolution. When OFDM systems are compared to single carrier systems in terms of AOA estimation, the main advantage is that for each subcarrier, the received phase depending on the angle of arrival is different. This results in diversity in the angle of arrival equations. In this work, we will also concentrate on the advantage of this diversity and its improvement on the accuracy of location estimation systems as well as the location based services that can be developed based on the obtained accuracy levels."