·         2000-   Bugshan/Bell Labs Chair Professor, Department of Electrical Engineering, King Fahd University of Petroleum &     Minerals (KFUPM), Dhahran, Saudi Arabia.

·         Director, Telecommunications Research Laboratory, KFUPM, 2001- .

·         1997-00 Professor, Department of Electronics and Information Engineering, The Hong Kong Polytechnic University,   Hong Kong.

·         1998-00 Director, Wireless Information Systems Research (WISR) Centre, The Hong Kong Polytechnic University,   Hong Kong.

·         1992-97 Director, PCS Research Laboratory, Department of Systems and Computer Engineering, Carleton University, Ottawa, Canada

·         1988-91 Associate Chairman for Graduate Studies, Department of Systems and Computer Engineering, Carleton University, Ottawa, Canada.

·         1985-98 Professor Department of Systems and Computer Engineering Carleton University, Ottawa, Canada

·         1981-85 Associate Professor, Department of Systems and Computer Engineering Carleton University, Ottawa, Canada

·         1978-81 Associate Professor, University of Garyounis Benghazi, Libya

·         1975-78 Post-doctoral Research Fellow University of Birmingham, Birmingham, England

·         1972-75 Lecturer, University of Tripoli, Tripoli,  Libya

·         1970-72 Visiting Professor, Department of Electronics, University of Tabriz, Tabriz, Iran

·         1970-70, Assistant Professor, University of Engineering and Technology, Lahore, Pakistan

·         1969-70 Lecturer, Department of Electrical Engineering, University of Engineering and Technology, Lahore, Pakistan

·         1965-69 Research Assistant, Department of Electrical Engineering, University of Birmingham, England

·         1964-65 Lecturer, Department of Electrical Engineering, University of Engineering & Technology, Lahore, Pakistan.