According to the industry analysis of China Report Hall in 2025, the snake shaped inverted F antenna has become the mainstream solution for miniaturization design of TWS earphones. A new antenna from a leading manufacturer using this technology has a total length of only 37 millimeters, which is 40% shorter than traditional designs. This antenna optimizes the current path through a bent layout, etched and formed on a resin dielectric plate with a dielectric constant of 4.4. The radiating plate is made of ultra-thin copper foil with a thickness of 0.1 millimeters, perfectly embedded in the limited space inside the earphone handle.
To cope with complex environmental interference, the R&D team conducted multiple rounds of performance tuning: after loading aluminum batteries and horn components, the antenna terminal length was optimized to 1.2 millimeters to stabilize the resonant frequency at 2.46GHz and expand the bandwidth to 130MHz; When loading the human head model for testing, further fine-tuning was made to 0.6 millimeters, and the final resonant frequency was accurately locked at 2.44 GHz, with a SAR value of only 1.77 W/kg, which is lower than the upper limit of international safety standards. Actual testing shows that the antenna radiation efficiency reaches -0.96dB, fully meeting the needs of daily communication and music playback.
