High-speed transmission signal lines are a type of transmission medium characterized by low loss, low crosstalk, high shielding, and impedance matching. They are capable of stably transmitting high-capacity data or high-speed electrical signals in high-frequency bands ranging from hundreds of MHz to tens of GHz, serving as the crucial "veins" supporting modern high-speed communication systems. Their applications span multiple core fields such as information communication, consumer electronics, and industrial automation.