Selection and Application of the Data Transfer Operating Protocol Software Architecture for the Software-Defined Radio

Introduction. The demodulator structure is described and decoding algorithm for signal-code constructions development is presented. The structure and functional description of the developed software (SW), which is designed for the installation of the software-defined radio in the radio stations layout, are presented. The frame structures of the broadcast and half-duplex protocols, modulation/demodulation and subsequent digital signal processing in existing and prospect radio communication systems are considered.Objective. Investigation of modulation/demodulation methods and subsequent digital signal processing along with requirements imposed by them on the network stations equipment and system operation algorithms.Materials and methods. The software for the software-defined radio system layout is developed to demonstrate the reliability and operability of the proposed algorithm and transmission protocol. It can be used to receive and transmit information by using ionospheric reflections. Present design takes into account existing standards and amateur systems such as WinLink and information systems (digital and analog) for the "physical" and "channel" levels.Results. The structure and functional description of the developed software for the software-defined radio system layout are given. The possible realization of the software-defined radio channel for data receiving and transfer by using ionospheric reflections is presented. The results of technical solutions experimental testing are shown. The software can use hardware and software to control the transceiver module, which includes the SunSDR2 transceiver and antenna amplifier.Conclusion. The structure and functional description of the developed software are presented as a result of the software architecture selection and its application investigation. It is concluded that the reliability and operability justification of the proposed algorithm and transmission protocol is relevant in a field of the digital receivers development for communication systems of various purposes. The presented experimental studies data on verification of the proposed algorithm show the feasibility of present solutions on the qualitative utilization of the channel resource by using the described code structure. The present results allow to determine the most appropriate and efficient way of the software development allowing to create a technique that can meet the maximum number of possible assignments of radio access channels.