我需要你生成3段约50词的英文短文本。 我希望这3段文本分别来自通信、雷达、光学领域。我希望你通过学术搜索引擎特别是IEEE Xplore、Arxiv等搜索近年的文献。文献语言为英文。搜索时间单位在2019年以后。搜索关键词请你根据热门话题自行选择。在完成文献搜索之后我需要你在它们的Introduction中节选我所需的文本。

Communication: With the rapid growth of wireless communication technologies, the demand for high-speed and reliable communication systems has increased significantly. In recent years, the application of multiple-input multiple-output (MIMO) technology has attracted extensive attention due to its ability to enhance the system capacity and reliability. In this paper, we present a new approach for MIMO transmission that utilizes constellation rotation and differential encoding techniques to improve the performance of wireless communication systems.

Radar: Radar systems play an essential role in various applications, such as military, aerospace, and meteorology. In recent years, the development of radar technology has focused on improving the resolution and accuracy of radar systems. In this paper, we introduce a new radar imaging technique based on compressive sensing theory. This method can effectively reduce the number of measurements required for imaging, thereby improving the efficiency of radar systems.

Optics: Optical imaging technology has been widely used in biomedical imaging, industrial inspection, and security systems. In recent years, the development of advanced optical imaging techniques with high resolution and sensitivity has become a hot research topic. In this paper, we present a new optical imaging system based on the principle of structured illumination microscopy (SIM). The proposed system can achieve super-resolution imaging with a lateral resolution of 90 nm and an axial resolution of 200 nm, which is superior to conventional optical microscopy techniques.