Comparison of Possible Approaches for the Development of Low-Budget Spectrum Analyzers for Sensor Networks in the Range of 2.4–2.5 GHz

The article deals with the development, implementation and research of the spectrum analyzers that can be used in sensor networks and Internet systems of things. As an operating frequency range, 2.4–2.5 GHz ISM is selected. At the stage of hardware selection, a comparative analysis of existing available microcontrollers for the analysis of the spectrum, the choice of hardware interfaces, the ordering of the required modules and electrical components, as well as the input control is carried out. During development, several variants of spectrum analyzers on the basis of microcontroller and TI Chipcon СС2500 microcontrollers with USB interfaces, as well as Cypress CYWUSB6935 modules with LPT and USB interfaces, have been implemented. At the development stage, the development of the printed circuit board, its fabrication, component assembly, microcontroller programming, the verification of the assembly's robustness, making corrections, connecting to a personal computer and assembly in the case have been carried out. An analysis of existing software for collecting information on the state of the wireless broadcast is also conducted. According to the results of comparative experiments of various collections of spectrum analyzers, spectrographs for different types of signals were obtained. On these typical spectrographs a comparative analysis of the work of various prototypes was conducted. The offered approaches to building sensors on the basis of spectrum analyzers allow to create low-power modules for embedding in existing wireless information networks of enterprises for prevention of inter-channel interference and ensuring the integrity of data transmission. As a result of experiments, it is evident that not all existing modules are very different in characteristics, and the quality of their work is directly related to the type and quality of the antenna. The article gives the basic electric circuits, a list of elements, examples of PCBs, programmers, software and prototypes.