Components that make up a RF Communication System

Communication is the process of transferring information from one place to another. The information that is generated at the source is transferred to the receiver through communication channel.

From the diagram above, on the source side, there is a transmitter device that makes the input electrical information suitable for efficient transmission over a given channel. Generally a transmitter modulates amplitude or frequency of a high-frequency carrier wave by an original electrical information signal which is known as the baseband signal.

On the destination side, the receiver is the device that receives information from the channel and demodulates the electrical signal from it. The receiver also amplifies and removes noise and distortion from the noise contaminated received signal.

The output transducer converts electrical signal from the receiver output to a form of message as required by the user. Communication can be done in two forms: Analog communication and Digital communication.

You can also read: Basics of a RF communication systems

RF Communication System Components

A Radio Frequency (RF) communication system consists of various components and each performs different functions as detailed below:

• Phase locked oscillators (PLO): Generates the RF carrier at the required frequency.
• Modulator: Varies the frequency, amplitude, or phase of an IF carrier to put information to it.
• Upconverter: Shifts the modulated intermediate frequency (IF) signal to RF signal.
• Power amplifier: Increases the power level of the modulated RF carrier.
• TX antenna: Transmits the RF carrier in the direction of the receiver.
• RX antenna: Collects the transmitted RF signal at the receiver.
• RF filter: Allows only specified range of RF frequencies to pass and blocks all other frequencies.
• A low-noise amplifier (LNA): Amplifies the weak received RF carrier.
• Mixer and IF amplifier: Shifts the RF carrier to a lower frequency below the RF band and amplifies it to a level where it can be demodulated.
• Demodulator: Removes the information from the low-frequency carrier.

The block diagram above applies to any type of wireless RF communication system e.g. Cellular phone, Wireless, LAN, Satellite communication system etc. Any RF communication system must contain all of the devices shown in the block diagram but performance requirement of each device vary from system to system.

Related articles:

• Radio Frequency (RF) Signal Generator – Features & Applications
• Demodulation in Telecommunication Systems
• RF Scalar and Vector Network Analyzers