Continuous wave (CW) Doppler radar is a type of radar system that continuously transmits and receives radio frequency signals without interruption. Unlike pulsed radar systems that alternate between transmitting and receiving, CW radar continuously emits a continuous wave signal. CW Doppler radar works based on the Doppler effect, which is the change in frequency of waves (in this case, radar waves) caused by relative motion between the radar system and a target object.
When the radar wave reflects off a moving target, the frequency of the received signal moves proportionally to the speed of the target along the radar’s line of sight.
The principle of CW Doppler radar revolves around the continuous transmission and reception of a radio frequency signal. The radar continuously emits a single signal and receives the reflected signal from moving targets. The frequency Doppler shift between the transmitted and received signals is directly related to the radial velocity of the target relative to the radar system.
By measuring this frequency shift, CW Doppler radar can determine the speed and direction of moving objects, such as vehicles, aircraft or weather systems.
CW Doppler Radar offers several advantages for specific applications. A key advantage is its ability to accurately measure high speeds, including the speed of fast-moving targets such as aircraft and vehicles. CW radar is also effective for continuously monitoring speed changes over time, making it suitable for applications requiring real-time speed measurements or Doppler frequency analysis.
Another advantage is its simplicity and reliability in detecting moving targets without the need for complex timing or pulse generation circuits, making CW Doppler radar systems cost-effective and easier to implement in certain applications.
Pulse Doppler radar and CW Doppler radar differ mainly in their operational modes and capabilities. Pulse Doppler radar alternates between transmitting short pulses of radio frequency energy and listening for echoes, allowing it to measure both target range (distance) and radial velocity (speed toward or away radar).
This allows Pulse Doppler radar to detect and track targets at longer ranges and in cluttered environments, as well as distinguish between stationary and moving objects. In contrast, CW Doppler radar continuously transmits a continuous wave signal and detects Doppler shifts in the frequency of the reflected signal to measure the target speed. Although CW Doppler radar is simpler and more suitable for accurately measuring high speeds, Pulse Doppler radar offers more comprehensive capabilities for range and speed measurements in various radar applications