Research and development of an algorithm for automatic link establishment in the shortwave range

The task of establishing a point-to-point connection is to set the transmitting and receiving devices to the same carrier frequency. If all devices use a single frequency, it will be impossible to transfer data between multiple devices in parallel. Therefore, the transmitter and receiver must choose the same carrier frequency from several options. This article describes the algorithm for automatic link establishment. The algorithm automatically analyzes the frequency channels for the SNR, selects a free frequency and adjusts both devices to it. The calling device sends a special data packet. A receiving device that scans all radio frequency channels determines whether a given call is intended for it. After a triple handshake, the connection is established. To study the algorithm, a mathematical model was built in the MatLab environment. This allowed to estimate the number of channels that ensure the effective use of the algorithm.