一种高速场景中的前导序列设计与检测方案

针对高速移动场景下的随机接入过程中大多普勒频移导致系统解调性能恶化的问题,提出一种随机接入前导序列设计与检测方案。该方案利用频率偏移引起的相关函数峰值偏移距离与Zadoff-Chu(ZC)序列根索引的关系,将两个共轭对称的前导序列组合为一个新的随机接入前导序列,并针对该序列进行两级联合检测。仿真结果表明,与传统LTE标准中使用的限制集相比,该方案不仅提高了可用前导序列数量,还可有效地避免了整数倍频偏对定时估计误差的影响,增强了在高载波频率及高速移动场景下的随机接入检测性能。

A Design and Detection Scheme of Preamble Sequence in High-Speed Scenario

In order to solve the problem of system demodulation performance degradation due to the large doppler shift during random access in high-speed mobile scenarios,a random access preamble sequence design and detection scheme is proposed.This scheme combines the two conjugate symmetrical preamble sequences into a new preamble sequence by using the relationship between the peak offset distance of the correlation function and the Zadoff-Chu (ZC) sequence root index caused by the frequency offset,and implements two-stage joint detection for the new sequence.The simulation results show that compared with the limit set used in the traditional LTE standard,the proposed scheme can not only improve the number of available preamble sequences,but also effectively avoid the influence of integer frequency offsets on timing estimation error,and enhance the performance of random access detection in high carrier frequency and high-speed mobile scenarios.