Simulation And Research On FLASH-OFDM System In IEEE802.20 Agreement

With the development of the Mobile Broadband Wireless Access technology, a new kind of technology which is named FLASH-OFDM has appeared. And the technology becomes one core of the IEEE802.20 Agreement. FLASH-OFDM technology is the Fast Low-latency Access with Seamless Handoff-Orthogonal Frequency Division Multiplexing. It consists of LDPC, high-speed Frequency Hopping and the high efficiency OFDM modulation. LDPC has the characteristic of the high coding gain, the high decoding performance and the property closing to the Shannon limit. It can improve the OFDM performance effectively in multi-paths. High-speed Frequency Hopping is strong in capability for multipath disturbance. It can greatly improve the reliability of data transfers. FLASH-OFDM system can support the multiuser data transfers, and also, can provide the better security. FLSH-OFDM system makes the data communication and the voice communication come true. The IP layer-structure in the system can satisfy users'requirements of the high bandwidth and Qos. So it has better network compatibility and scalability than other communication system. It proves that the FLASH-OFDM system has the advanced technology, the well transmission performance and the well prospect of applying by the analyzing of the Bit Error Rate and the planisphere. To improve the FLASH-OFDM system, the algorithm uses the LMMSEE channel estimation algorithm. It reduces the system's error rate, increases the channel estimation accuracy and improves the system performance. At present, there is the theoretic description of the whole FLASH-OFDM system. There is no research of the concrete data of the Physical Layer in the system. The article fills a gap in the field. It affords the reference model and the data for other researcher, by emulation mode. And also, the article has an apocalypse function in the research and application on it.