High Data Rate Transmission Based On Turbo-OFDM For UAV

The data transmitted between UAVs and the main station include telecontrol information, telemetry information and task sensor information. High data-rate communication is required because of large amount of task seneor information. This paper analyses and researches the high data-rate transmission technology based on Turbo-OFDM for UAV, and can be summarized as follows.1. Introduce slow Ricean fading channel model to analyse the channel characteristics of UAV system.2. A new metric for Turbo decoding on Ricean channel is derived with the knowledge of channel estimation variance. The simulation results show that Turbo decoding with the proposed metric can obtain 0.1-06 dB code gain than that with conventional metric. Furthermore, this algorithm can be generalized to the fading channel.3. Combining the advantages of Turbo code and OFDM, we propose a new decoding metric for Turbo coded OFDM system over multipath fading channel. This algorithm can bring out 2.9 dB code gain when FER (frame error ratio) is 10"3 and the variance of signal-to-noise ratio is 0.2. Also from the derivation, it is concluded that the mean and variance of signal-to-noise ratio are important to the performance.4.Considering the performance and decoding delay, two adaptive Turbo-OFDM schemes are proposed, which obtain low bit error ratio and high decoding speed over the flat fading channel. And the performance of the two schemes is analyzed and studied.5. Analyze the transmission speed and the anti-jamming capacity. The results show that the system can provide up to 54 Mbps transmission speed and superior anti-jamming capacity.The theoretic research and simulation results show that Turbo-OFDM technology is an effective and efficient way to realize the high data-rate transmission for UAV with its superior performance.