中国邮电高校学报(英文) ›› 2011, Vol. 18 ›› Issue (4): 59-64.doi: 10.1016/S1005-8885(10)60084-2

• Wireless • 上一篇    下一篇

Precoding with interference suppression sequence scheme for OFDM-based cognitive radio systems

赵成林1,张鹍2,孙学斌1,蒋挺1   

  1. 1. 北京邮电大学信息与通信工程学院
    2. 北京邮电大学
  • 收稿日期:2010-11-05 修回日期:2011-02-18 出版日期:2011-08-31 发布日期:2011-08-24
  • 通讯作者: 张鹍 E-mail:zhangkun_2008@foxmail.com
  • 基金资助:

    This work was supported by the National Science and Technology Specific Major Projects (2009ZX03006-006, 2009ZX03006-009), and the National Natural Science Foundation of China (60432040, 60972079).

Precoding with interference suppression sequence scheme for OFDM-based cognitive radio systems

  • Received:2010-11-05 Revised:2011-02-18 Online:2011-08-31 Published:2011-08-24
  • Contact: Kun ZHANG E-mail:zhangkun_2008@foxmail.com
  • Supported by:

    This work was supported by the National Science and Technology Specific Major Projects (2009ZX03006-006, 2009ZX03006-009), and the National Natural Science Foundation of China (60432040, 60972079).

摘要:

Orthogonal frequency division multiplexing (OFDM) is considered to be one of the promising schemes for cognitive radios (CR) systems, due to its flexibility in spectrum shaping. However, the traditional way of spectrum-notching failed to suppress out-of-band leakage enough, resulting in interference with licensed users (LUs). A novel spectrum shaping scheme is proposed in this article, where a precoder with interference suppression sequence (ISS) is for the first time introduced for shaping the spectrum of OFDM signals in OFDM-based CR systems. The precoder matrix together with ISS matrix is obtained by minimizing the power of out-of-band interference, which results in the sufficient interference suppression of OFDM signal to LUs. Analysis and simulation results show that the proposed scheme can significantly suppress the interference power to LUs at a little cost of precoding efficiency. Meanwhile, the peak-to-average-power-ratio (PAPR) is invariable and the bit-error-rate (BER) performance over Rayleigh fading channel is improved.

关键词:

OFDM, cognitive radio, precoding, spectrum shaping

Abstract:

Orthogonal frequency division multiplexing (OFDM) is considered to be one of the promising schemes for cognitive radios (CR) systems, due to its flexibility in spectrum shaping. However, the traditional way of spectrum-notching failed to suppress out-of-band leakage enough, resulting in interference with licensed users (LUs). A novel spectrum shaping scheme is proposed in this article, where a precoder with interference suppression sequence (ISS) is for the first time introduced for shaping the spectrum of OFDM signals in OFDM-based CR systems. The precoder matrix together with ISS matrix is obtained by minimizing the power of out-of-band interference, which results in the sufficient interference suppression of OFDM signal to LUs. Analysis and simulation results show that the proposed scheme can significantly suppress the interference power to LUs at a little cost of precoding efficiency. Meanwhile, the peak-to-average-power-ratio (PAPR) is invariable and the bit-error-rate (BER) performance over Rayleigh fading channel is improved.

Key words:

OFDM, cognitive radio, precoding, spectrum shaping