Development of a Prototype Data Transmission Device Using Radio Over IP Principles for CNR 900 Military Radios

Abstract

The purpose of this research is to develop a prototype communication system using the CNR 900 military radio model to enhance digital data transmission channels utilizing Radio Over Internet Protocol (RoIP). This system integrates with the mobile radio system of armored vehicles in the Black Panther Battalion's E-ARMY, allowing for command and control operations in disaster-stricken or hard-to-reach areas by extending the communication range through radio relay stations. The research involves directly converting Digital Encrypted Voice signals with the CNR 900 military radio set and interfacing it with a Raspberry Pi4 microprocessor. The voice signals are then filtered using CMOS Wideband technology to connect to the internal telephone system of the army. Additionally, the RoIP system is connected to the internal Internet network through a Private Server on a Linux operating system. Testing is conducted using Morse code transmission programs to assess the accuracy of the radio voice signals passed through the prototype. The results demonstrate accurate transmission and decoding of Thai and English alphabets and numerals, with every word decoded correctly. Furthermore, the Signal to Noise Ratio (SNR) is measured to evaluate the quality of the radio voice signals connected to the telephone set, with values exceeding 25 dBm, indicating suitable support for voice signal transmission through the prototype system.