摘要
在WIMAX系统中,基站通过分配OFDM子载波的方式可同时与多个用户通信.由于不同用户与基站的距离不同,通常采用测距来估计用户与基站之间的往返传输时延,并在通信中给予补偿以实现不同用户与系统的同步,从而克服用户的远近效应,保证系统的正常工作.测距码检测是测距的关键.本文主要研究了WIMAX系统中的测距码检测算法,利用测距码的相关性和信号功率等特点,提出一种简化的测距码检测算法,利用能量检测、硬判决、测距码初选和测距码终选4个模块,实现测距码的检测.与传统频域估计算法以及时域遍历算法相比,本文算法复杂度低、性能好、实用.
In WIMAX system, the base station communicates with several users simultaneously by allocating sub-carriers in one OFDM symbol to different users. As the distances from different users to the base station vary, ranging algorithm is adopted to estimate the transmission delay between the base station and the user. Meanwhile, time synchronization is acquired by compensating the estimated time delay in transmission, so as to overcome the near-far effect of different users and guarantee the system performance. The ranging code detecting is critical for the ranging algorithm. In this paper, the ranging code detecting algorithm of the WIMAX system is studied. According to the relativity and signal power of the ranging code, a simplified ranging code detecting algorithm is proposed. The ranging code is detected through four modules： power detection, hard decision, coarse selection and final selection. Compared with the traditional frequency domain ranging algorithm and the time domain ergodic algorithm, the algorithm proposed in this paper is less complex, but has better and more practical performance.
出处
《深圳职业技术学院学报》
CAS
2015年第3期3-8,共6页
Journal of Shenzhen Polytechnic
基金
深圳市科技创新委员会基金资助项目(项目编号:6014-21K190294995)
关键词
子载波
测距码
同步
硬判决
sub-carriers
ranging code
synchronization
hard decision
