Information on Frequency Modulated Continuous Wave Radar
A major limitation of continuous wave radar (CW radar) is
that it lacks the ability to measure distance to a
target. CW radar cannot determine target range because it lacks
the timing mark necessary to allow the system to time
accurately the transmit and receive cycle and convert this into
range. In pulse radar, this mark was provided by the
pulse itself. Pulse radar transmits a form of amplitude-modulated energy.
There are other forms of modulation that provide the necessary
mark to allow range information to be calculated. Frequency modulation
(FM) can also be used. CW radars making use of
FM are called frequency modulated continuous wave radar
(FM CW radar or sometimes FMCW radar).
In addition to
the ranging limitations, the CW radar is unable to detect
targets with a zero Doppler shift, including stationary targets and
beaming targets. Like pulse radar, frequency modulated continuous wave radar (FM CW radar) overcomes this limitation.
Other topics in our resources on Radar related to Frequency Modulated Continuous Wave Radar include: