Triplexer

Triplexer is a 4-port filtering device that splits one input in to three different outputs each with a different frequency. It can also be used the other way round and where it routes signals at three different frequencies to a single port. A triplexer enables a single co-axial cable to run into the feed of three different antennas.
This bi-directional device usually consists of 3 bandpass filters with different passband frequencies. triplexer is ideally used in smartphones, radar and other wireless transmitter and receiver systems.