A direct Tire Pressure Monitoring System (TPMS) is a module assembled in a car tire which comprises a pressure sensor, a microcontroller, a battery, an RF transmitter, and an RF antenna. The pressure data is transmitted by radio frequency at 434 MHz or 315 MHz from module to car. High power efficiency of the module’s functions is mandatory in order to achieve a long battery lifetime. In this respect the connection between RF transmitter and RF antenna is a crucial part of the module. A matching network consists of several passive components, namely capacitors and inductors. Normally the matching network is optimized to work at either 434 MHz or 315 MHz by choosing distinct component values for either frequency.