DESIGN AND IMPLEMENTATION OF RADIO RECEIVER AT 8.222-8.746 MHZ BASED ON SUPERHETERODYNE RECEIVER FOR SHIP COMMUNICATION

• Main Author: LESTARI - NIM : 18114017, RESTI
• Format: Final Project
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/30339
• Institution: Institut Teknologi Bandung

<p align="justify">Radio frequency device is a communication device that has been developed and is still in use today. Some areas still use radio technology as a means of communication, such as maritime, aviation, and military. Although frequency allocation has been done for each field, there is still frequent misuse of frequency. One example is the disruption of flight communication due to misuse of frequency by traditional fishermen in the territory of Indonesia. <br /> <br /> In this final project, the design of special radio receiver system for ship communication frequency. By using this design, fishermen can not receive communications outside of their designation. The design of this ship radio uses the concept of bidirectional transceiver, that is, some of the circuit functions can work back and forth or be used when transmitting and receiving. The frequency settings of this radio design use VFO or DDS using programming principles to limit frequency tunning. In the design of this ship radio used high frequency or HF type SSB. The main feature of this device is that it can be used for voice communication in half duplex. Frequency channel used is channel 810 with frequency range 8.222 MHz up to 8.746 MHz. The receiver system uses the principle of superheterodyne receiver which consists of several subsystems namely amplifier, mixer, and filter. The implementation results show the receiving system can be used for ship communication of HF spectrum of 8.222-8.746 MHz. SSB demodulation can be applied with upper side band selection. This device can receive audio frequencies below 4,500 Hz according to ITU-R BS.640-3 recommendation. Radio receiver device can operate on monitoring the frequency of Indonesian ship communication at 8.403 MHz and the device can be used to receive communication in the range 8.222-8.746 MHz (channel 810) according to Report ITU-R M.2082.<p align="justify"> <br />