CAJ | 학술논문

针对现有正交频分多址(OFDMA)系统初始测距算法检测性能不佳以及复杂度过高的问题，该文提出一种低复杂度迭代干扰消除的多用户初始测距算法。该算法采用迭代并行干扰消除方法，在接收端按照最大功率准则并行检测活动测距用户的有效径，利用估计出的有效径参数信息来减小信道估计中的干扰，再通过重构和并行消除多用户测距信号。计算机仿真结果表明，与连续多用户检测(SMUD)干扰抵消算法相比，当信噪比为9 dB，且一个测距时隙内测距用户数为8时，所提算法的复杂度大约是SMUD的25%，检测性能大约提高了5%。
침대현유정교빈분다지(OFDMA)계통초시측거산법검측성능불가이급복잡도과고적문제，해문제출일충저복잡도질대간우소제적다용호초시측거산법。해산법채용질대병행간우소제방법，재접수단안조최대공솔준칙병행검측활동측거용호적유효경，이용고계출적유효경삼수신식래감소신도고계중적간우，재통과중구화병행소제다용호측거신호。계산궤방진결과표명，여련속다용호검측(SMUD)간우저소산법상비，당신조비위9 dB，차일개측거시극내측거용호수위8시，소제산법적복잡도대약시SMUD적25%，검측성능대약제고료5%。
To solve the issues of the low detection performance and high computational complexity of the available initial ranging algorithms for Orthogonal Frequency Division Multiple Access (OFDMA) systems, a low-complexity initial ranging algorithm with iterative interference cancellation is presented. By using the Parallel Interference Cancellation (PIC) scheme in an iterative fashion, the proposed algorithm detects parallelly the valid paths of active users by means of the strongest power criterion at the receiver, and mitigates the channel estimation interference by employing the parameters estimation of the valid paths. Then it rebuilds and cancels parallelly the detected multiusers’ signals. Simulation results show that when there are 8 initial ranging users in one ranging time slot and the signal noise ratio is 9 dB, the computational complexity of the proposed algorithm is approximately 25% of that of the Successive MultiUser Detection (SMUD) with interference cancellation algorithm, and the detection performance is improved by 5%compared with SMUD.