This paper investigates the connection between college physics courses and professional courses related to radio communication. First, it reviews the historical development of thermal noise research, clarifies the origin of the concept of noise temperature, and provides a general definition of noise temperature. Next, taking the antenna as an electromagnetic wave transducer, it derives the quantitative expression for the antenna thermal noise power spectral density by combining the theory of blackbody radiation with Kirchhoff's law of thermal radiation. Based on revealing the physical mechanism of antenna thermal noise, the paper elaborates on the logical construction and physical connotations of the concept of antenna noise temperature. Teaching practice has shown that integrating the above ideas into teaching deepens students' understanding of the relevant physical knowledge. This study aims to deepen students' understanding of the blackbody radiation theory in college physics courses and provide a reference for the teaching of radio communication professional courses. By extending the basic physical theory to the field of radio communication, it demonstrates the bridging role of basic physics courses in the curriculum system, which is conducive to cultivating students' interdisciplinary comprehensive literacy and innovative thinking abilities.

It is a meaningful exercise that discussing the patterns of interference fringes in case introducing polarizers into the Young's double slit experiment while different combinations. However, “no fixed phase difference,” the commonly seen answer, does not fully understand the essence of the problem. By utilizing Malus's Law and the principle of wave superposition, this paper calculates the resulting contrast after superposition. Quantitative calculations demonstrate that when three polarizers are introduced in Young's double-slit interference experiment, the physical reason for the absence of interference fringes is the existence of a projection phase difference. Moreover, it is emphasized that in this context, the projection phase difference is the determining factor for the presence or absence of interference fringes. The article provides a clear and intuitive physical image, suitable for classroom teaching, displaying the role of the projected phase difference and aiding students in gaining a deeper understanding and application of concepts related to light emission mechanisms, interference, polarization, and the interference of polarized light.