RF Circulator: Advantages and Disadvantages

rf circulator
microwave device
wave propagation
rf component
ferromagnetic material

This page explores the advantages and disadvantages of RF Circulators. It also provides links to various topics related to RF Circulators.

What is a Circulator?

Introduction: A circulator operates based on the non-reciprocal property of ferromagnetic materials. When such materials are placed in a DC magnetic field, electromagnetic wave propagation becomes non-reciprocal. It is a microwave passive device that allows uni-directional propagation of electromagnetic waves, similar to an isolator. It has many applications.

Figure 1 depicts one such application used to share a single common antenna between a transmitter and a receiver.

rf circulator

In this 3-port circulator, the signal travels in uni-directional mode, i.e., from port 1 to 2, and from 2 to 3, and so on. The reverse is not possible. This means a signal fed at the Nth port appears at the (N+1)th port, but not at the (N-1)th port.

As a result, the signal from the transmitter at port 1 can be transmitted via the antenna connected at port 2. Similarly, a signal received at port 2 can be fed to the receiver connected at port 3.

The following are the types of Circulators:

  • Four-port circulator and Three-port circulator (based on the number of ports)
  • Microstrip circulator
  • Strip line circulator
  • Waveguide circulator

Benefits or Advantages of Circulators

The following are the benefits or advantages of Circulators:

  • It has many applications as it is a lossless and non-reciprocal device.
  • The 3-port circulator can be used as an RF isolator by terminating one of its ports.

Drawbacks or Disadvantages of Circulators

The following are the disadvantages of Circulators:

  • There is a limit on the power handling capability of the RF circulator. This can be increased by lowering impedance, increasing the intrinsic line width, or increasing substrate thickness.
  • Insertion loss between coupled ports depends on various parameters such as copper loss of the strip and ground plane, dielectric loss of input/output strips, and magnetic loss of the ferrite disc. All these should be properly managed in order to achieve minimum insertion loss between the coupled ports.
RF Circulator Manufacturers: A Comprehensive Guide

RF Circulator Manufacturers: A Comprehensive Guide

Explore a list of RF circulator manufacturers, categorized by frequency range, for applications like WLAN, Zigbee, WiMAX, LTE, VSAT, and cellular technologies.

rf circulator
rf component
wireless technology
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Barrettor vs. Thermistor: Understanding the Key Differences

Explore the differences between barrettors and thermistors, including thermal time constant, operating temperature, broadband suitability, and detector sensitivity, for microwave power measurements.

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power measurement
thermistor