College of Information and Communication Engineering, Harbin Engineering University, Harbin 150001, China.
Wuhan Maritime Communication Research Institute, Wuhan 430200, China.
Sensors (Basel). 2022 Sep 19;22(18):7092. doi: 10.3390/s22187092.
Quadrature amplitude modulation (QAM) constellation and Golay complementary sequences (GCSs) are usually applied in orthogonal frequency division multiplexing (OFDM) systems to obtain a higher data rate and a lower peak-to-mean envelope power ratio (PMEPR). In this paper, after a sufficient search of the literature, it was found that increasing the family size is an effective way to improve the data rate, and the family size is mainly determined by the number of offsets in the general structure of QAM GCSs. Under the guidance of this idea, we propose a new construction for 4q-QAM GCSs through generalized Boolean functions (GBFs) based on a new description of a 4q-QAM constellation, which aims to enlarge the family size of GCSs and obtain a low PMEPR. Furthermore, a previous construction of 4q-QAM GCSs presented by Li has been proved to be a special case of the new one, and the family size of new sequences is much larger than those previously mentioned, which means that there was a great improvement in the data rate. On the other hand, a previous construction of 16-QAM GCSs presented by Zeng is also a special case of the new one in this paper, when q=2. In the meantime, the proposed sequences have the same PMEPR upper bound as the previously mentioned sequences presented by Li when applied in OFDM systems, which increase the data rate without degrading the PMEPR performance. The theoretical analysis and simulation results show that the proposed new sequences can achieve a higher data rate and a low PMEPR.
正交频分复用（OFDM）系统中通常采用正交幅度调制（QAM）星座和戈莱互补序列（GCS）来获得更高的数据速率和更低的峰均包络功率比（PMEPR）。在本文中，经过对文献的充分搜索，发现增加序列族的大小是提高数据速率的有效方法，而序列族的大小主要由 QAM GCS 通用结构中的偏移数决定。在这个思想的指导下，我们通过基于 QAM 星座的新描述，提出了一种新的 4q-QAM GCS 构造方法，通过广义布尔函数（GBF），旨在扩大 GCS 的序列族大小并获得低 PMEPR。此外，Li 提出的先前的 4q-QAM GCS 构造已经被证明是新构造的一个特例，新序列的序列族大小比之前提到的大得多，这意味着数据速率有了很大的提高。另一方面，本文中当 q=2 时，Zeng 提出的先前的 16-QAM GCS 构造也是新构造的一个特例。同时，当应用于 OFDM 系统时，所提出的序列具有与 Li 提出的先前序列相同的 PMEPR 上限，即在不降低 PMEPR 性能的情况下提高数据速率。理论分析和仿真结果表明，所提出的新序列可以实现更高的数据速率和更低的 PMEPR。
