Synchronization technology for OFDM system

Overview

As a wireless transmission technology with high-spectrum efficiency, OFDM is extensively applied in the next-generation broadband wireless communication systems.

The Communication Technology Research Department conducts deep and detailed research on some key steps in OFDM technology. For example, when the terminal synchronizes time and frequency with base station in high-speed movement, the synchronization time will increase due to Doppler frequency offset caused by high-speed movement, interference from adjacent base stations and channel fading effects. As a differential technology and innovation with other companies, we propose an advanced high-performance and fast synchronization scheme which is adopted in the next-generation wireless communication products.

Solution

A novel coherent calculation method is utilized for the capture of timing and the estimation of frequency offset. A pre-processing module and a protection procedure are used to enhance the robustness of the algorithms under low SNR and fast fading channels. In addition, our proposal effectively solves conflictions between frequency offset compensation and time synchronization and speeds up synchronization capturing speed.

Technical points

• Pre-processing module
• Robust coherent calculation algorithm.
• Fast and effective frequency offset compensation and timing capturing methods

Synoptic diagram

Effect

It is able to provide fast and reliable synchronization access even under the low SNR and high-speed movement scenarios. Simulation results indicate that the average synchronization time inthe cell-edge is much quicker than it of the conventional method under the high-speed movement environment (120km/h).

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Contact Information:

Wang Xin: wangxin@cn.fujitsu.com

Sun Gang: sungang@cn.fujitsu.com

Wu Jianming: jianming.wu@cn.fujitsu.com