Application of Orthogonal Frequency Division Multiplexing for Transmission

• Main Authors: Kai-Yuan Chuang, 鍾凱源
• Other Authors: Hsin-Piao Lin
• Format: Others
• Language: zh-TW
• Published: 2006
• Online Access: http://ndltd.ncl.edu.tw/handle/ygjjb5

碩士 === 國立臺北科技大學 === 光電與通訊產業研發碩士專班 === 95 === For many years, the TV professional signals have been transmitted via satellites. However, this way of transmissions is easily influenced by the high buildings in Taipei, climate, the difficulties for adjustments, and high cost of satellite feeds. And the SNG vehicles are incapable of mobile transmissions. The thesis presents a framework based on Orthogonal Frequency Division Multiplexing Technology (OFDM) that has been tested in Taipei City. The video/audio baseband signals are compressed by MPEG-2 sent to OFDM and modulated into direct waves or multi-paths. It has been transmitted from 25 specific places. Reception equipments were located in the 95th floor of Taipei 101. Three variables were closely observed : Signals to noise ratio, anti-noisy performance, and picture quality. The final results are expected to organize a list of valid sites for mobile transmissions . OFDM technology has been tested on 25 sites within Taipei. Success rate is 88% except three locations. According to this result, we can safely argue that OFDM technology can be efficiently applied to transmit signals. The analyses of OFDM also suggest ways to improve the performance of traditional FM microwaves. Except the following possibilities：interferences by skyscrapers or lack of reflective objects, the OFDM assuredly could be applied in Taipei basin for mobile transmissions with greater satisfaction.