In monitoring engine bearing temperatures, challenges such as antenna installation and signal transmission difficulties often arise. This paper proposes a comprehensive design for an extremely near-field telemetry antenna based on surface acoustic wave temperature sensors. Firstly, the electromagnetic field distribution characteristics in the extremely near-field region are obtained through theoretical analysis, and a wideband antenna with an in band reflection coefficient of less than -10 dB is designed through simulation optimization in the 2~3 GHz frequency band. Next, an antenna cage is introduced with a rational assembly structure. Furthermore, by covering the surface of the extremely near-field antenna with a dielectric superstrate, the energy transfer efficiency is improved by approximately 14.80%, thereby enhancing signal transmission quality and reducing the rate of change during energy transfer by about 54.36%, which ultimately increases the stability of the subsequent telemetry system. Finally, after installing the sensor on the extremely near-field antenna and connecting it to the telemetry system, actual temperature measurements are conducted during bearing operation, validating the practicality of the extremely near-field antenna, its assembly structure, and the feasibility of the dielectric superstrate method.