To reduce signal transmission loss through connecting wires, the core is to minimize all four channels: "resistance loss, dielectric loss, reflection loss, crosstalk and radiation loss". Firstly, regarding resistance loss, we should try to shorten the trace length and thicken the conductor cross-section. When the frequency rises to a point where skin depth becomes significant, switch to multi-strand silver-plated copper wires or Litz wires to distribute the current evenly over a larger surface area. At the same time, control the contact resistance in the terminal crimping area to the level of 0.1 mΩ. If necessary, use gold-plated terminals and add anti-oxidation coatings to avoid additional loss caused by fretting corrosion. Secondly, for dielectric loss, select insulating materials with low dielectric constant ε_r and low tangent of loss angle tanδ, such as foamed PE or PTFE, which can reduce the attenuation from 0.3 dB/m at 1 GHz to below 0.1 dB/m. At the same time, keep the outer diameter of the insulation uniform to prevent sudden changes in characteristic impedance at local points. Thirdly, to suppress reflection loss, it is necessary to ensure continuous characteristic impedance throughout the entire link: after calculating the target impedance, use a network analyzer to sweep the frequency segment by segment. If the standing wave ratio is found to be greater than 1.3, promptly replace the impedance matching section or add a π-type attenuation network. For high-speed differential pairs, it is also necessary to strictly control the internal delay difference, adopt parallel twisted-pair or star-twisted structures, and keep the skew within 5 ps. Fourthly, crosstalk and radiation loss are addressed by "shielding + grounding": add a double-layer braided shield to the high-frequency wire and press it onto the metal housing in a 360° ring at the interface to form a complete Faraday cage. If multiple high-speed lines are running in parallel, adopt an alternating arrangement of ground-signal-ground, or insert a complete reference plane between adjacent signal layers to reduce near-end crosstalk by more than 20 dB. Finally, the wiring environment should also be optimized simultaneously: route the analog small signal lines and motor power lines in separate slots, maintaining a 90° angle when crossing. For long-distance outdoor links, use low-loss coaxial or fiber-optic cables instead of copper cables, which can reduce the total attenuation of a 100-meter link from more than ten dB to the order of magnitude of 0.3 dB. Through a comprehensive design that integrates "material-geometry-impedance-shielding-environment", the insertion loss of the entire connecting wire can be reduced to the theoretical lower limit, ensuring clear signal eye diagrams and bit error rates that meet standards.