A micromechanical sensor for measuring millimetric wave or microwave
power, which sensor includes a wave line for conducting the millimetric
or microwave power and a moving part and a fixed electrode, in such a way
that the capacitance (C) between the moving part and the fixed electrode
couples to the wave power advancing in the wave line. According to the
invention, the capacitance (C) between the moving part and the fixed
electrode is divided into at least two portions (C/n), which are located
at a distance from each other, in such a way that the wave power
advancing in the wave line couples to the portions (C/n) of the
capacitance (C) consecutively and experiences the inductive load between
the portions (C/n) of the capacitance (C). Thus the frequency band of the
sensor can be substantially broadened and the reflective coefficient can
be kept reasonably small.