Simplex – Definition and Pronunciation
What is Simplex?
Simplex is the ability of a communication channel to carry communication traffic in one direction only.
Examples of Simplex
The distress call and message is broadcast to ALL STATIONS, in the SIMPLEX mode of transmission. The radiotelephony distress call consists of: the distress signal MAYDAY, spoken three times; the words THIS IS; the name and any other identity of the vessel in distress, spoken three times.
From “Radio Calling Procedures Improving Clarity and Efficiency in Radio Transmissions”.
The VHF channel plan, as described in the International Radio Regulations, shows a total of 59 VHF channels available for marine use: 56 channels are allocated for radiotelephone (voice communications); 22 of these channels operate in simplex mode (transmission and reception taking place on a single frequency); 34 of these channels operate in duplex mode (simultaneous transmissions and reception taking place on separate but paired frequencies).
From “Marine VHF Radio – Communication and Emergency”.
FEC is a system of error control for data transmission wherein the receiving device has the capability to detect and correct, in a simplex mode (1-way communication channel), any character or code block that contains fewer than a predetermined number of symbols in error.
From “DVB-S2 Modulation Extensions and Other Advances”.
Pronunciation of Simplex
