A novel subspace method for precise carrier frequency offset estimation in multicarrier modulation scheme under multiuser environment,International Journal of Communication Systems

当前位置： X-MOL 学术 › Int. J. Commun. Syst. › 论文详情

Our official English website, www.x-mol.net, welcomes your feedback! (Note: you will need to create a separate account there.)

A novel subspace method for precise carrier frequency offset estimation in multicarrier modulation scheme under multiuser environment
International Journal of Communication Systems ( IF 1.7 ) Pub Date : 2020-09-19 , DOI: 10.1002/dac.4608
Chitra S ₁ , Kumaratharan N ₂ , Ramesh S ₃

Affiliation

In recent years, the demand on data communication is rapidly increasing, and there is a need of spectrally efficient modulation scheme for massive data transmissions. Multicarrier modulation (MCM) is widely used in wireless systems to support high data rate multimedia services such as audio, video, image, and data. Multicarrier code division multiple access (MC‐CDMA) is one of the MCM techniques which combines the best features of orthogonal frequency division multiplexing (OFDM) and code division multiple access (CDMA). The carrier frequency offset (CFO) due to oscillator instabilities or Doppler shifts greatly deteriorates the performance of MC‐CDMA system. Hence, the subcarriers are no longer orthogonal and introduce intercarrier interference (ICI) at the receiver. The simultaneous CFO estimation and compensation in multiuser mobile environment are a challenging task which needs to be addressed for optimum performance. The blind CFO estimation such as maximum likelihood estimation (MLE) has limited estimation range which is less than half the subcarrier spacing. Multiple signal classification (MUSIC) is the spectral estimation‐based subspace method suited for simultaneous CFO estimation in the multiuser environment. MUSIC offers precise CFO estimation only for the well‐spaced CFOs and fails to discriminate the strictly spaced CFOs. Hence, a novel subspace method is proposed in this paper to improve the estimation accuracy for closely spaced CFOs with the reduced computational complexity. Simulation results show that the proposed enhanced root MUSIC estimation outperforms MLE and MUSIC in terms of estimation accuracy, bit error rate (BER), and ICI power.

中文翻译：

多用户环境下多载波调制方案中精确载波频率偏移估计的新子空间方法

近年来，对数据通信的需求迅速增长，并且需要用于大量数据传输的频谱有效调制方案。多载波调制（MCM）广泛用于无线系统中，以支持诸如音频，视频，图像和数据之类的高数据速率多媒体服务。多载波码分多址（MC-CDMA）是MCM技术之一，它结合了正交频分复用（OFDM）和码分多址（CDMA）的最佳功能。由于振荡器不稳定性或多普勒频移引起的载波频率偏移（CFO）大大降低了MC-CDMA系统的性能。因此，子载波不再正交，并且在接收机处引入载波间干扰（ICI）。在多用户移动环境中，同时进行CFO估算和补偿是一项艰巨的任务，必须解决这一问题才能获得最佳性能。诸如最大似然估计（MLE）之类的盲CFO估计具有有限的估计范围，该范围小于子载波间隔的一半。多信号分类（MUSIC）是基于频谱估计的子空间方法，适用于多用户环境中的同时CFO估计。MUSIC仅对间隔良好的CFO提供精确的CFO估计，而无法区分严格间隔的CFO。因此，本文提出了一种新颖的子空间方法，以降低计算复杂度的方式提高了近距离CFO的估计精度。

更新日期：2020-10-16

点击分享查看原文

点击收藏

阅读更多本刊最新论文本刊介绍/投稿指南11