Radio frequency power sensor based on MEMS technology - Sensors, 2003. Proceedings of IEEE

We present the first measurement results of a power sensor for radio Pequency ( r j signals (50 kHz 40 GHz) with almost no dissipation during the measurement. This sensor is, therefore, a ‘through’power sensor, that means that the rfsignal is available during the measurement of its power. The power detection has been realized by measuring capacitively the movement of a grounded aluminum membrane, which is suspended above the transmission line carrying the rf signal. The power sensor is thus a capacitive MEMS technology based sensor. The fabrication is done by aluminum su$ace micromachining on an AF45 glass wafer, We measured the capacitance as a firnction of the applied $power and found a linear relationship as predicted from iheory.