As the electronics is developing, the more complex devices have more strict requirements of electromagnetic emission. Accordingly, the testing methods are also much more complex. In order to be the maximum disturbance (conductive or radioactive) of the various circuit elements measurable, it is necessary to model in some depth the operating environment of the controller.
The automotive control units are operating also as communication centers (gateway), therefore they have to serve a large number of LIN, CAN and FlexRay channels. As a result of the optical isolation used in the EMC measurements, a lot of optical isolator modem required, which greatly complicates the measurements for various reasons. Therefore it is appropriate based on economical and measurement technological considerations to design a communication multiplexer.
In the thesis first I look through the automotive industry’s main communication protocols and the optical fiber solutions. After that, I go around the difficulties and problems designing of the circuit, and I try to find solution proposals for them. From the possible alternatives I select the most suitable one, and I deal with its realization in the rest of the dissertation. At first I implement the circuit in an FPGA, and the operation of it I check with computer simulations. After that, using the development boards made available to me, I assemble a demo device, what I can also test in real environment. It becomes clear by the experiences gained, that a more simple programmable logic device can also provide the functionalities as required, so at the end of the thesis I design a cheaper, CPLD-based compact target device.