摘要
正交频分复用作为一种高效的数据传输方式,它能够提供较高的频谱效率,但相对运动的物体会使信号的收发产生多普勒频移,多普勒频移会影响OFDM子载波之间的正交性,这将严重影响系统的性能。然而在移动速度不变的情况下,高空环境下的多普勒频移变化要小于地面,通过仿真证明高空下多普勒频移对系统误比特率的影响比地面系统降低50%-60%,并使用ACK函数算法证明当多普勒频移大于200Hz时,系统性能显著提升。
Orthogonal frequency division multiplexing is a kind of efficient data transmission mode,which can provide high spectral efficiency,but the relative motion of the object can enervate Doppler shift owing to the transmis-sion and receiving of the signal,and the Doppler frequency shift will affect the orthogonality between the sub carriers of OFDM,which will seriously affect the performance of the system.However,in the case of the moving speed,the Doppler shift of the high altitude environment is less than that of the ground.It is proved that the bit error rate of the system is reduced by 50%-60%,and the performance of the system is significantly improved by using the ACK function algorithm.
出处
《软件》
2016年第1期57-60,共4页
Software
关键词
正交频分复用
平流层通信
多普勒频移
Orthogonal frequency division multiplexing
Stratospheric communication
Doppler shift
