Agile and compact near-field analyses of onboard Bluetooth module by live electrooptic imaging

Potentially prompt and compact method for near-field analyses both in the real and wavenumber spaces have been applied successfully to RF emissions from a commercially available onboard Bluetooth module. The new method is based on real-time images of near electric field, acquired and displayed by the live electrooptic imaging technique in the asynchronous operation mode. Such near-field features of the module have been clarified as precise location of emission origin, geometries of wave fronts, distribution of wave-vectors, and angular dependence of emission power.