This master's thesis presents the development of the hardware required to design a low-cost through vector network analyzer in the X-band. In addition to the hardware, drivers required to initialize and communicate with digital circuits, as well as software for communication via a virtual USB serial interface. For control, support for commands compatible with the SCPI standard is implemented. First, existing systems of a similar type are analyzed. Based on the findings, a block diagram is drawn up. The blocks include two mixers with filters in the GHz and MHz frequency ranges, an oscillator, a frequency source based on the ST STuW81300, a mixed-signal unit featuring a TI ADS4222 for sampling and conversion, and a Lattice iCE40UP5k for storing and processing signals. The main circuit, with an ST STM32H563, manages the process. Component selection is based on cost, functionality, scalability, and open-source tool compatibility. This is followed by the assembly and the elimination of any design issues. Once the software is developed, the communication with the terminal is tested, followed by measurements of module properties. It is found that, while it functions within the desired range, there is room for improvement. It is also found that the selected FPGA is too slow to serve as a buffer or signal processor, making it unsuitable for this purpose. Two solutions are proposed: direct sampling using the microcontroller or selecting a faster gate array. Further steps for development and possible future improvements are also proposed. It is concluded that building such a low-cost system is feasible, but further development is necessary to make it viable for production.
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