Journal of Nuclear and Related Technology Vol. 4, Special Edition 2007, 199-208 GROUND RECEIVING STATION (GRS) OF UMS – RECEIVING AND PROCESSING THE ELECTROMAGNETIC WAVE DATA FROM SATELLITE Mohammad Syahmi Nordin & Fauziah Abdul Aziz Physics With Electronics Programme, School of Science and Technology, Universiti Malaysia Sabah, Kota Kinabalu, 88999, Sabah, MALAYSIA e-mail : afauziah@ums.edu.my ABSTRACT The low resolution Automatic Picture Transmission (APT) data from the National Oceanic and Atmospheric Administration (NOAA) polar-orbiting satellites Advanced Very High Resolution Radiometer (AVHRR) is being received and recorded in real-time mode at ground receiving station in School of Science and Technology, Universiti Malaysia Sabah. The system is suitable for the developing and undeveloped countries in south and Southeast Asia and is said to be acceptable for engineering, agricultural, climatological and environmental applications. The system comprises a personal computer attached with a small APT receiver. The data transmission between the ground receiving station and NOAA satellites is using the electromagnetic wave. The relation for receiving and processing the electromagnetic wave in the transmission will be discussed. Keywords: - NOAA, APT, AVHRR, electromagnetic wave, ground receiving station INTRODUCTION Remote sensing is the process of collecting information about material objects without coming into physical contact with them. Human eyes are a good example of remote sensors. They collect enormous amounts of information about the world around without actually making physical contact. Satellite instruments are a lot like eyes. Both rely on waves of scattered and emitted electromagnetic radiation as their means for gathering information. In order to gain an appreciation for the ground station equipment required to receive the polar orbiting direct readout imagery, it is better to understand of the sensors of electromagnetic wave on board of NOAA satellites, and how the APT images are created, formatted, and transmitted from the satellites to direct readout ground stations. ELECTROMAGNETIC RADIATION The properties of the electromagnetic radiation can be classified by showing wave nature and showing particle characteristics. The electromagnetic wave theory from Maxwell considers electromagnetic energy as propagating in harmonic sinusoidal wave motion. It consists of inseparable oscillating electric and magnetic field that are always perpendicular to each other and to the direction of travel. The electromagnetic waves have constant velocity in a vacuum, but may vary in wavelength and frequency (Gupta, R. P., 1991). 199