## 1 Introduction  
Recently, the demand for satellite missions has grown and become more complex, driven by advancements in communication, Earth observation, and scientific research. Consequently, research on the development of high-gain antennas has become increasingly critical, and the applications of large-scale antennas have expanded significantly [1, 2, 3]. In recent decades, several antenna-reflector design concepts have been proposed. Among these, the mesh antenna reflector is regarded as one of the most suitable types for large deployable antennas owing to its light weight, high accuracy, and small packed volume [4, 5, 6]. With the increasing demand for mesh antenna reflectors, the mechanical properties of mesh fabrics have received increasing attention. The most commonly applied fabrics for antennas are warp knits, and the warp knitting parameters are crucial in determining the knitting process as well as the electrical and mechanical properties of the mesh fabric [7]. Among these parameters, opening per inch (OPI) is used to measure the weave density of the mesh fabric, and refers to the number of holes per inch. Normally, OPI is increased to reduce loss as the mission operating frequency band of the antenna increases [8]. The optical properties of the mesh reflector include transmittance, which is determined by the pore characteristics of the mesh fabric. Transmittance quantifies the ability of a mesh fabric surface to transmit light and is proportional to the pore size per unit area of the mesh fabric. Although opening per inch (OPI) is the main factor in determining pore size, other parameters such as yarn diameter, pattern, and the number of ply yarns can also alter pore dimensions, even at the same OPI. Consequently, the optical properties of the mesh, including transmittance, absorptance, and reflectance, vary accordingly. These optical properties are critical in determining the thermal behavior and temperature gradients of the antenna when exposed to extreme space thermal environments. Significant temperature gradients on the reflector can cause thermal deformation, leading to surface contour errors that degrade radio frequency (RF) performance and antenna pointing accuracy [9; 10; 11]. Therefore, predicting the thermal characteristics of the reflector in an orbital environment requires a thorough analysis of the optical properties influenced by mesh fabric parameters. Additionally, it is essential to investigate in advance how these optical properties affect the thermal behavior of the mesh reflector in the orbital thermal environment. Various studies have described the importance of investigating the optical properties to analyze the thermal behavior of mesh antennas. The fact that these optical properties can serve as factors needed to solve thermal design problems for maintaining the surface accuracy of mesh antenna reflectors has been demonstrated. [PERSON] et al. [12] proposed favorable material properties for large deployable mesh antennas by measuring the optical properties according to the wire material and coating methods, comparing the absorption rates of different materials based on the presence of gold plating, and analyzing the rate of change in the material properties with wavelength. [PERSON] et al. [13] described a method for measuring the optical properties of a mesh woven with a nichrome wire to ensure the thermal reliability of a mesh antenna reflector in an on-orbit thermal environment. However, previous studies have not investigated the thermal properties of the mesh antenna reflector surface through an on-orbit thermal analysis based on the measured optical properties of the mesh. Furthermore, variations in the optical properties depending on various design factors of the mesh and the thermal effects between the mesh and the antenna reflectors have not been examined.