摘要
为保证无人飞机在动态环境下数据传输的稳定性和可靠性,提出了一种循环正交M元扩频上行链路数据传输方案。按此方案传输数据,发送信号不存在潜在的周期性,系统的抗干扰和抗截获性能得到了很好的保障。在动态环境中,由于载体具有较大的加速度,载波多普勒频移剧烈变化,普通接收机载波跟踪环极易失锁,故提出一种基于经验值查表的载波跟踪算法,在锁频环内引入经验值查找表,环路能自适应调整环路滤波器带宽,从而实现任意时刻的高精度载波跟踪。
A novel uplink data transmission scheme based on cycle-orthogonal M-ary spectrum spreading was proposed for unmanned aerial vehicles （UAVs）. According to this scheme, potential periodicity in the transmiting signal is eliminated and the data is hard to detect or intercept with conventional technologies, thus the anti-jamming and anti-intercepting capabilities of the system can be achieved. In the dynamic circumstance, the great move speed and acceleration of the carrier results in drastic variation in carrier wave Doppler frequency shifts, which makes the tracking loop of general receivers out of balance. A FPLL tracking scheme based on look-up tables（LUT） was proposed, which adopts a list of empirical values in FLL and the bandwidth of the loop filter in FLL can be adjusted adaptively. As a result, a more precise tracking can be attained at any time.
出处
《吉林大学学报（工学版）》
EI
CAS
CSCD
北大核心
2010年第1期276-280,共5页
Journal of Jilin University:Engineering and Technology Edition
基金
国家自然科学基金项目(60572148
60702060)
高等学校学科创新引智计划项目(B08038)
关键词
通信技术
无人机
循环正交M元扩频
载波跟踪
communication technology
unmanned aerial vehicle （UAV）
cycle-orthogonal M-ary spread spectrum
carrier tracking
