Abstract
The launch of three Beidou satellites in 2000 and 2003 has opened a new chapter in China’s satellite communications development. Satellite subsystems comprising antennas, power amplifiers and radio frequency transmitters and receivers are usually dominated by overseas suppliers. However, CityU’s wireless communications experts have successfully tapped into about 25% of the market in key Beidou Global Positioning System components, namely antennas and power amplifiers. What sets CityU apart from other suppliers is a unique filter device embedded in the amplifiers, developed by Dr Quan Xue and Professor C H Chan, experts in RF circuitry. The filter enhances the quality of signal transmission and reception, with stabilized performance under a wide temperature range, from +50 to -40 degrees Celsius. The amplifiers outperform other competitive products but the cost is much cheaper. With almost 20 years of research experience in patch antenna, Professor K M Luk developed the circularly polarized (CP) antennas specifically for the Beidou satellite system. Unlike patch antennas, which are primarily used for receiving signals, the more sophisticated CP antennas can both receive and transmit signals. The zone of signal coverage is much wider. A spin-off company has been established in Shenzhen to commercialize and transfer the above technologies to industry.

Contact Information
Mr H Y Wong
Director, Technology Transfer Office
City University of Hong Kong
83 Tat Chee Avenue
Kowloon, Hong Kong
Tel : (852) 2788 8428
Fax : (852) 2788 9119
Email : hy.wong@cityu.edu.hk