Time domain analysis for high frequency applications in the field of EMC compliance measurements: Novel method to trace transient RF disturbances

Time Domain Measurements have been used for several years in frequency applications below 1 GHz and very suitable to measure transient and time limited disturbing RF signals. The new generation of High speed Field Programmable Gate Arrays (FPGA) in combination with analogue digital converters and RF down converters enable measurements with high precision. The achievable measurement accuracy is directly comparable to high end RF test receivers with the conventional super heterodyne design. The achieved measurement accuracy could be used to design CISP 16–1–1 compliant digital RF receivers. The additional technical features like real time spectrum and high speed Quasi Peak detector measurements open new analysis methods to understand RF disturbances. Typical examples of complex RF signals which have to be measured under CISPR standards are all automotive electronic modules which are controlling the internal communication bus system, internal RF devices (automotive WLAN, UMTS, GSM, WCDMA, MIMO, multiband smart phones, Net-books) and all on board regenerative energy systems using high power switching devices like Insulated Gate Bipolar Transistors (IGBT), or inverters.