摘要
针对无人机巡航过程中控制链路受到多径衰落、多普勒效应的严重影响,结合无人机控制链路通信频率与通信带宽较低而可靠度要求很高的特点,文章将二维扩频技术应用在无人机控制链中。对无人机巡航速度为1 080km/h、多普勒频移达到60Hz、多经时延大于OFDM保护间隔的信道条件进行仿真,通过仿真对比了频域扩频、直接序列扩频在该条件下各自性能的缺陷。分析表明,在同等增益条件下二维扩频技术可以有效地解决无人机高速巡航时产生的多普勒效应与多经衰落,使得在低信噪比的情况下大大提高无人机控制链路的可靠性。
The UAV control link is serious effected by the Doppler effect and multipath. Based on the characters of UAV control link communications, which are the low frequency, narrow communication bandwith, and the higher reliability demanding characteristics, two-dimensional spread-spectrum technology used in UAV control link is presented. The performances between the frequency-domain spread spectrum and direct sequence spread spectrum are compared with the condition of 60Hz Doppler frequency shift, cruise speed of 1 080km/h and muhipath delay greater the OFDM guard interval. The results shows that with the conditions of equal-gain, two-dimensional spreadspectrum technology can effectively solve Doppler effect and multipath fading generated by the UAV high-speed cruising, and greatly improved UAV Control Link reliability in low SNR.
出处
《空间电子技术》
2010年第1期42-45,共4页
Space Electronic Technology
基金
陕西省自然科学基金资助项目(2007F03)
2007年陕西省工业科技攻关计划资助项目(2007k04-10)
