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IT-based manufacturing industry has become a vital part of national competitiveness.

Since the first railway in the world was put into use in 1825, various countries have vied with each other to break the maximumtrain speed records.

China’s high-speed railway construction has now made remarkable achievements.The pattern of four vertical and four horizontal high-speed railroads has basically taken shape, covering 90 per cent of China’s population.

The railway communication system is an integrated and complete communication system especially for offering audio, visual and digital communication services for transportation and operation management.

The application of train’s high-speed movement makes it difficult for vehicle-ground wireless communication to reach satisfying speed and reliable access rate.

Security, stability and high rate are the objective requirements of the high-speed wireless communication.