College of Engineering

Abstract: An omni-directional antenna for telemetry, tracking and command (TT&C) com- munications is required for spin-stabilized geostationary satellites whether in the launching phase or once in orbit. The need for a despun platform can even be reduced by implementing a conformal microstrip antenna array °ush mounted on the cylindrical surface of the satellite for that purpose. The analysis and design of this kind of antennas is quite complicated and a powerful simulation software proves indispensable to achieve this goal.

Abstract: This thesis deals with design and analysis of both fullband and subband adaptive filters and compared between them with applications in real speech. . The Normalized Least Mean Square (NLMS) algorithm has been used to make control an adaptive filter. In fullband adaptive filter the system shows slow convergence time compared with subband adaptive filter with lower signal to noise ratio is gave about 0.00003 noise reduction with (S/N) = 3.24 dB according to woman voice and gave 0.000015 with (S/N) =3.68 dB according to man voice when both tested with real speech.

Abstract: Performance and flexibility of mobile radio systems essentially depend on the choice of the multiple access scheme. The novel Multicarrier Code Division Multiple Access (MC-CDMA) scheme which is the topic of this thesis is a promising alternative to conventional FDMA, TDMA, and CDMA schemes. With MC-CDMA, each data modulated chip of the user specific spreading code is mapped onto a separate subcarrier, so that the chips of the spreading code and, hence, the data symbol is transmitted in parallel on multiple subcarriers which introduces frequency diversity.