J4 ›› 2013, Vol. 40 ›› Issue (4): 79-84+154.doi: 10.3969/j.issn.1001-2400.2013.04.013

• 研究论文 • 上一篇    下一篇

波束成形辅助的连续干扰消除OFDMA初始测距算法

夏玉杰1,2;任光亮1   

  1. (1. 西安电子科技大学 综合业务网理论及关键技术国家重点实验室,陕西 西安  710071;
    2. 洛阳师范学院 物理与电子信息学院,河南 洛阳  471022)
  • 收稿日期:2012-03-20 出版日期:2013-08-20 发布日期:2013-10-10
  • 作者简介:夏玉杰(1978-),男,西安电子科技大学博士研究生,E-mail: yjxia@mail.xidian.edu.cn.
  • 基金资助:

    国家自然科学基金资助项目(61072102);国家科技重大专项资助项目(2011ZX03001-007-01)

Beamforming assisted successive interference cancellation initial ranging algorithm for OFDMA systems

XIA Yujie1,2;REN Guangliang1   

  1. (1. State Key Lab. of Integrated Service Networks, Xidian Univ., Xi'an  710071, China;
    2. School of Physics and Electronic Information, Luoyang Normal Univ., Luoyang  471022, China)
  • Received:2012-03-20 Online:2013-08-20 Published:2013-10-10

摘要:

针对影响正交频分多址(OFDMA)网络中初始测距系统性能的多径信道频率选择性和多用户接入干扰(MAI)的问题,利用新一代无线通信系统基站的智能天线,提出一种新的波束成形辅助的多用户连续干扰消除初始测距算法.所提算法通过一组波束成形矢量,从空间上将一个小区分成若干个小的测距区域,抑制了其他小区域中测距用户的干扰,提高了每个小区域中测距用户的信噪干扰比.在每个小测距区域中,采用简化的连续干扰消除方法和自适应门限进行多用户测距码检测和时偏估计.计算机仿真结果表明,与已有连续多用户检测干扰抵消(SMUD)算法相比,在15个测距用户和SNR为-6dB时,所提出的算法比SMUD算法的正确检测概率提高了80%.

关键词: 正交频分多址(OFDMA), 波束成形, 初始测距, 连续干扰消除

Abstract:

According to the effect of the frequency selectivity of multipath channel and multiuser access interference (MAI) on the initial ranging system in the orthogonal frequency division multiple access (OFDMA) network, a novel beamforming assisted successive interference cancellation initial ranging algorithm is presented by utilizing smart antennas at the base station in the next generation wireless communication systems. In the algorithm, the cell is divided into many small ranging sectors in the spatial domain by a group of beamforming vectors. The proposed algorithm is able to improve the signal-to-interference-plus-noise ratio of the desired ranging users in a given sector and suppress the MAI from other ranging sectors. In the small ranging sector, the multiuser ranging code detection and timing offset estimation are conducted by the simplified successive multiuser detection and interference cancellation (SMUD) method and the adaptive threshold. Simulation results show that the correct detection probability of the proposed algorithm is improved by 80% than that of the SMUD algorithm, with 15 ranging users in the ranging channel when the SNR is -6dB.

Key words: orthogonal frequency division multiple access, beamforming, initial ranging, successive interference cancellation