Practical Implementation of Index Modulation-Based Waveforms
Practical Implementation of Index Modulation-Based Waveforms
复制标题
DOI：
10.1109/access.2017.2771200
复制
发表时间：
2017-11
期刊：
影响因子：
3.9
通讯作者：
Selahattin Gokceli;E. Başar;Miaowen Wen;G. Karabulut Kurt
中科院分区：
文献类型：
--
作者：
Selahattin Gokceli;E. Başar;Miaowen Wen;G. Karabulut Kurt
最近提出了具有索引调制（OFDM-IM）的正交频分复用（OFDM）技术，以提供优于传统OFDM的性能改进。OFDM-IM包括不同的数据传输机制，其中通过特别激活所选择的子载波并使其他子载波无效来在子载波模式上传输附加数据比特。然而，由于不活动的子载波，这种机制固有地导致一些低效率。为了提高OFDM-IM技术的频谱效率，提出了具有索引调制的双模OFDM（DM-OFDM），其中通过使用第二信号星座来激活被置零的子载波。利用DM-OFDM，可以获得显著的数据速率改进。作为一个重要的问题，在文献中，OFDM-IM及其有效的变化，如DM-OFDM，只进行了研究，在计算机模拟和理论分析。因此，它们的实时性能尚未被研究以评估它们在下一代网络中的潜力。针对这一差距，在本文中，OFDM-IM和DM-OFDM技术的实时实现，通过使用软件定义无线电技术。National Instruments USRP-2921节点用于单输入单输出配置。通过这种实现，提供了详细的实时结果和性能观察。此外，针对OFDM-IM和DM-OFDM在频谱抑制和误码性能方面的局限性，提出了一种混合OFDM-IM（H-OFDM-IM）方案，该方案可以看作是OFDM-IM和DM-OFDM的结合。使用H-OFDM-IM，可以获得频谱遏制和错误性能的显着改善，这些观察表明其适用于实时使用和下一代网络。通过计算机仿真和试验验证了上述结论。
Orthogonal frequency division multiplexing (OFDM) with index modulation (OFDM-IM) technique has been recently proposed to provide performance improvements over conventional OFDM. OFDM-IM includes a different data transmission mechanism, where additional data bits are transmitted over subcarrier patterns by specifically activating selected subcarriers and nulling the others. However, such a mechanism inherently causes some inefficiency due to the inactive subcarriers. To improve the spectral efficiency of the OFDM-IM technique, dual-mode OFDM with index modulation (DM-OFDM) is proposed, where nulled subcarriers are activated by using a second signal constellation. With DM-OFDM, a significant data rate improvement can be obtained. As an important missing issue in the literature, OFDM-IM and its effective variations, such as DM-OFDM, have only been studied in terms of computer simulations and theoretical analysis. Therefore, their real-time performance is not yet investigated to assess their potential for next-generation networks. Addressing this gap, in this paper, OFDM-IM and DM-OFDM techniques are implemented in real-time by using software defined radio technology. National Instruments USRP-2921 nodes are used in a single-input single-output configuration. With this implementation, detailed real-time results and performance observations are provided. Moreover, a hybrid OFDM-IM (H-OFDM-IM) scheme, which can be seen as the combination of OFDM-IM and DM-OFDM, is proposed by targeting the limitations of both OFDM-IM and DM-OFDM in terms of spectral containment and error performance. With H-OFDM-IM, noticeable improvements in spectral containment and error performance can be obtained, and these observations show its suitability for real-time use and next-generation networks. With comprehensive computer simulation and test results, these claims are verified.