Duplexer

Not to be confused with diplexer.

For other uses, see Duplex (disambiguation) and duplex printing.

Commercial 19" rack mount antenna filter
Isolation typical >75 dB
Insertion Loss typical < 1.0 dB

A duplexer is a device that allows bi-directional (duplex) communication over a single channel.

In radar and radio communications systems, it isolates the receiver from the transmitter while permitting them to share a common antenna. Most radio repeater systems include a duplexer.

Note 1: A duplexer must be designed for operation in the frequency band used by the receiver and transmitter, and must be capable of handling the output power of the transmitter.

Note 2: A duplexer must provide adequate rejection of transmitter noise occurring at the receive frequency, and must be designed to operate at, or less than, the frequency separation between the transmitter and receiver.

Note 3: A duplexer must provide sufficient isolation to prevent receiver desensitization.

Source: from Federal Standard 1037C

See also

• Circulator

External links

• Duplexer theory