FAQ-Why Isolator is used at output of Amplifier?

This page mentions function of isolator used at output of the Amplifier. It provides links to RF Isolator and RF Amplifier basics.

RF Amplifier function: It is RF device which amplifies input signal to produce amplified signal at its output port.

RF Isolator function: It is RF device which passes signal only in one direction i.e. from input port to the output port.

It prevents signal going in the other direction i.e. from output port to the input port.

rf isolator at amplifier output

To fulfill desired functionality as mentioned, RF isolator has been designed to have low insersion loss and high isolation. The same has been depicted in the top part of figure above.

RF amplifier devices are usually very costly. Due to high isolation of isolator, by using it at the output of amplifier, it prevents reflections to pass to the RF amplifier device. Hence it helps in damaging the amplifier and consecutively saves the cost.
Moreover due to low insertion loss, it does not add more attenuation to the RF signal chain.

RF RELATED LINKS

RF Isolator vs Circulator
RF Isolator
RF Amplifier
RF Terminology
Satellite Terminology
VSAT system overview
FDMA versus TDMA versus CDMA
VSAT SCPC
VSAT MCPC
RF Transceiver basics
C band RF Transceiver Design and Development
Microstrip basics and types
Design of RF frequency converter
RF Power Amplifier
what is modulation
satellite Modem design
RF Link Budget

RF and Wireless Terminologies

RF and Wireless tutorials

WLAN  802.11ac  802.11ad  wimax  Zigbee  z-wave  GSM  LTE  UMTS  Bluetooth  UWB  IoT  satellite  Antenna  RADAR