Design and Implementation of Blind Modulation Classification for Asynchronous MIMO-OFDM System
Design and Implementation of Blind Modulation Classification for Asynchronous MIMO-OFDM System
复制标题
异步MIMO-OFDM系统盲调制分类的设计与实现
DOI：
10.1109/tim.2021.3109737
复制
发表时间：
2021
影响因子：
5.6
通讯作者：
S. Majhi
中科院分区：
文献类型：
--
作者：
Amit Kumar Pathy;Anand Kumar;Rahul Gupta;Sushant Kumar;S. Majhi
本文设计并实现了一种基于树的多输入多输出异步正交频分复用(MIMO-OFDM)系统的盲调制分类算法。它可以对许多线性调制信号进行分类，例如二进制相移键控(BPSK)、四相相移键控(QPSK)、偏移QPSK、最小相移键控和16-正交幅度调制。所提出的分类器在存在未知频率、定时和相位偏移的情况下工作，并且不需要信道状态信息的先验知识。分类分三步进行。在第一步中，对接收信号进行预处理，以消除定时偏差的影响。第二步，通过计算频域信号的高阶累积量来提取关键特征。第三步，利用似然比检验确定阈值。给出了正确分类概率的封闭形式的理论推导。通过蒙特卡罗仿真，比较了该算法与已有算法的性能。最后，通过室内传播环境下的射频试验台测量对所提出的算法进行了验证。
In this article, we design and implement a tree-based blind modulation classification algorithm for asynchronous multiple-input–multiple-output and orthogonal frequency-division multiplexing (MIMO-OFDM) systems. It can classify many of the linearly modulated signals, such as binary phase shift keying (BPSK), quadrature phase shift keying (QPSK), offset QPSK, minimum shift keying, and 16-quadrature amplitude modulation. The proposed classifier works in the presence of unknown frequency, timing, and phase offsets and with no prior knowledge of channel state information. Classification is performed in three steps. In the first step, preprocessing is done on the received signal to nullify the effect of timing offset. In the second step, key features are extracted by calculating higher order cumulants of the frequency-domain signal. In the third step, thresholds are determined by using the likelihood ratio test. A closed-form theoretical derivation for the probability of correct classification is obtained. The Monte Carlo simulations are conducted to compare the performance of the proposed algorithm with the existing algorithms. Finally, the proposed algorithm is validated through radio frequency testbed measurements over an indoor propagation environment.