CW Radar: Advantages and Disadvantages

This page covers the advantages and disadvantages of CW Radar. It mentions CW Radar advantages or benefits and CW Radar disadvantages or drawbacks. It also describes CW radar basics.

What is CW Radar?

Introduction: The radar which works based on the use of continuous waveforms to determine target velocity is known as CW radar.

It works as follows: The frequency of the radar return wave (i.e., echo) remains at the center frequency (f0) from a stationary target, while it shifts by an amount equal to the Doppler frequency from a moving target.

By measuring the frequency difference, the target’s relative velocity can be measured using CW radar.

The figure below depicts a block diagram of the CW radar with transmitter and receiver parts.

The velocity of a moving target is measured using the following equation:

Target velocity, Vt = (fd/ft)* (Vo/2)

Where:

• fd = Doppler shift frequency
• ft = Transmitter frequency
• Vo = Free space velocity of EM wave

CW radar can be used for the following:

• To indicate the presence of a moving target.
• To find the radial velocity of a moving target.
• To find if an object is moving towards or away from the radar.
• To find a target’s bearing angle and elevation angle.

Benefits or Advantages of CW Radar

Following are the benefits or advantages of CW Radar:

• It is used for relative velocity measurement.
• It is used for a wide variety of applications as listed above.
• It transmits power with a lower value and hence does not interfere with other wireless devices.
• It is simple in construction.
• The performance of CW radar is not affected by stationary targets.

Drawbacks or Disadvantages of CW Radar

Following are the disadvantages of CW Radar:

• It does not measure the range or distance of the target.
• It becomes difficult to make a decision when there are a large number of targets. In this situation, the CW radar system gets confused.