Name all the parts in a digital radar system
- Display/operator
- Radar data processor (RDP)
- Exciter
- Transmitter
- Waveguide
- Duplexer
- Receiver
- Signal processor
Describe Exciter
Exciter – The purpose of an exciter is to generate a continuous, highly stable, low power signal at the desired frequency (which is fully selectable) and phase
for output to the transmitter. A Reference signal is also sent to the receiver for phase comparison of the
received pulse.
Describe Transmitter
Transmitter –The purpose of a transmitter is to produce the required Radio Frequency (RF) at sufficient power levels. Transmitters include magnetrons, klystrons and travelling wave tubes (TWTs).
Describe Duplexer
Duplexer - The purpose of the Duplexer is to permit the alternate use of the same antenna for both transmission and reception.
Describe antenna
Antenna - The purpose of the antenna, in a basic pulsed RADAR system, is to provide a coupling between free space and the transmitter / receiver. The antenna is used to transmit RF energy into space, concentrating that energy into a narrow beam. The antenna is also used to receive energy returned from RADAR targets.
Describe antenna couplers
Antenna Couplers - An antenna coupler is a device which makes it possible for one or two antennas to do the
electrical work of many, as opposed to using a separate antenna for each individual wavelength.
Describe Receiver
Receiver – The purpose of a receiver is to receive the weak echo from a target, amplify and present that echo to the signal processor in a suitable format for
processing.
Describe Signal processor
- Signal Processor - Digitised signals from the receiver are fed to the Signal Processor and sorted by range and doppler frequency (using a bank of Doppler Filters). The Signal Processor filters out ground clutter, and automatically detects target echoes. Echo locations are stored in a digital memory, then continuously scanned
for display. - Main goal is = Improve the signal to interference ratio
Describe Radar Data Processor
- RADAR Data Processor (RDP) - The purpose of the RDP is for:
– Control and performance of routine computations for all RADAR units.
– System timing.
– Scheduling operating mode selection e.g. long range
search, tracking and imaging modes (SAR / ISAR).
– Antenna stabilisation and control, sing aircraft Inertial Navigation Unit (INU) inputs.
– Track acquisition and target tracking.
Describe Display
Display – Provides the operator with a visual representation of target echoes.
Describe a magnetron
- The purpose of a magnetron is to convert a high energy DC pulse into an extremely high frequency pulse.
- It was commonly used in airborne RADAR due to its light weight, high efficiency, and small size.
– P3C APS-115 used a magnetron transmitter.
Describe a Traveling Wave Tube (TWT)
- The TWT is a broadband, low noise amplifier.
- Its advantage over a magnetron is its low noise factor.
– P-8 APY-10 use a TWT transmitter.
Describe Waveguides
- Waveguides are hollow, generally rectangular tubes that guide electromagnetic (EM) energy by reflecting energy off the inside surfaces of the waveguide.
