RF and microwave power meters are used in various areas of RF development, design, test, service repair and field service. RF power meters are available in different types such as in-line, absorptive, etc. Most of these types come with an RF sensor which is used to measure the RF power. The type of sensor that would be used for measuring the power usually depends upon the type of signal that needs to be measured.

For instance, a few types of sensors are suitable for measuring low powers, while others are applicable for modulation techniques. The following points give you a better understanding of the meaning, working and benefits of power sensors. Keep reading to know more.

What is an RF power sensor?

An RF power sensor can be described as an instrument that is connected via a cable to a meter and is capable of displaying power reading. Similar to the power meters, sensors are available in varied types and can be used for different applications.

How does an RF power sensor work?

Just like any other RF material, a power sensor has four electromagnetic parameters such as the real and imaginary of the electrical permittivity and magnetic sustainability. A power sensor operates by defining a sensitive volume and interrogating the value by these electromagnetic parameters. Then, a radio frequency antenna is used to define the sensitive volume, which is tuned into the sensor electronics (Sensorland.com, RF Sensors, n.d.).

What are the common types of RF power sensors?

As mentioned above, an RF power sensor is available in 2 types with different functions. The choice of the RF sensor being used will have an impact on the performance of the application.

Types of RF sensors

A. Diode detector based RF sensors

This type is used generally for analogue power meters. However, this technology can also be used for high-performance power meters. The main advantages of using this type are that it can help measure signals of extremely low levels of power and respond quickly as compared to the other types of heat-based varieties.

B. Heat-based RF sensors

This type is generally used to dissipate power from a source in a load and then measured the resulting temperature rise. Head based RF sensors can be further be classified into Thermistor and Thermocouple power sensors.

Why you should use RF sensors

These are a few advantages of using RF sensors such as:

•    Do not require any additional components such as magnets, coils, etc

•    Have a high signal-to-noise ratio that you can maximize by optimising the sensor design for a particular application

•    The output is dependent on speed unlike inductive sensors (AZO Materials, RF PROXIMITY SENSORS – CHARACTERISTICS, OPERATION AND APPLICATION IN MATERIALS RECYCLING, n.d.).

These are a few points that give you a brief idea about the meaning, operation, types and benefits of quality RF power sensors. For more details about the price or specifications of power meters, sensors, etc, contact a reputed retailer.