Portable devices, sensors and networks: wireless personalized eHealth services.

A frequency domain switch (100) utilizes an array of cantilevered beams (108) laminated with a piezoelectric material (126). Each of the beams has a unique geometry, and produces a sinusoidal electrical signal in the piezoelectric film that is assignable only to one of the cantilevered beams. When a free end of one of the cantilevered beams is deflected, it produces a signal that is analyzed by suitable circuitry (410-440) to read the position of the switch.