The Vissim Voice Communication system is a modular computer based communication system. This is not only a VHF system because it seamlessly integrates VHF, mobilephones, fixed line telephones and software telephones.
Most of the other remote operated VHF systems are single point-to-point systems where one or more VHF transceivers are operated from a central location. This means that there is no integration between the transceivers. If the transceivers are placed in the same location or near each other and operating on the same channel, there will be problems operating the system. A vessel calling will be heard over more than one receiver. Manual selection of station to answer the call requires evaluation of signal strength or knowledge of vessel position. When the Operator is transmitting to answer the call, he will hear his own voice coming back over the other transceivers.
The traditional way of solving this problem has been to use different channels for different areas. This means that the mariners have to change channel several times throughout the VTS area. Vessels crossing from one zone to another may be on different channels, and the VTS centre will often have to “hand over” vessels from one area (channel) to another.
The Vissim Voice Communication system offer all these functions in an integrated solution using advanced muting systems. If more than one Base Station receives the signal, the one receiving the best signal will be selected, and the others will be automatically muted during the vessels transmission. When the Operator is answering the call, the other Base Stations will be muted for the duration of the transmission to avoid feedback.