2. History
Robert Alexander Watson-Watt (1892-1973), a descendant of James Watt, received a degree in
Electrical Engineering from the University of St. Andrews, Scotland and in 1915 began a
career in the British civil service, He patented his first radio location device, a device for
locating atmospheric discharges, in 1919. In 1935, he received his eleventh radio-location
patent, a device for detecting and locating an approaching aircraft. In the following years he
was the leader of the intensive development of aircraft radio-location, the secret weapon of
the Battle of Britain. In 1937, before the war began, Watson-Watt and his wife undertook the
dangerous task of traveling disguised as ordinary tourists through Germany, searching for
signs of German radar stations.
3. Theory and Fundamentals of
Radar Operation
• Radar (radio detection and ranging)
• In 1888, Heinrich hertz demonstrated
that radio waves were reflected by
objects in the same manners light
waves
6. Components of Radar Systems
• Transmitter
– Creates high-powered radio pulses
– Operates in UHF band or higher
– Radar pulse last about one microsecond
7. Components of Radar Systems
• Antenna
– Antenna functions as both a transmitting and
receiving device
– Pulses emitted by the transmitter are routed to
the antenna using a waveguide--a hollow metal
channel that conducts the microwave energy to
the antenna
8. Components of Radar Systems
• Receiver
– Switched on as transmitter switches off
– Upon receiving a reflection, the radar system
measures the time difference between the
transmission and reception and uses this
calculation to determine the objects distance
from the antenna
– 12.36 microseconds is known as a radar-mile
9. Components of Radar Systems
• Indicator
– Air traffic control uses a cathode ray tube
known as a plan position indicator (PPI) radar
scope
10. Components of Radar Systems
• Indicator
– Center of PPI known as the MAIN BANG
11. Components of Radar System
• Moving target indicator (MTI)
– One way of eliminates ground clutter
– Other way is to raise antenna a few degrees
– Check pages 309 - 314 of textbook
13. Precision Approach Radar (PAR)
• Used primarily by the Department of
Defense as a precision landing aid.
14. • Developed in the 1940’s
• Before ILS
Precision Approach Radar (PAR)
15. • PAR consisted of a mobile facility
thus making it most effective for the
military
• Many PAR’s at airports were placed
in the middle so that they could be
turned
Precision Approach Radar (PAR)
16. Precision Approach Radar (PAR)
• PAR proved its effectiveness during
the Berlin Airlift, landing aircraft
every 90 seconds
• Some PAR’s still remain even though
ILS is the landing air of choice
20. Airport Surveillance Radar
(ASR)
• Primary short range radar used by
FAA
• Most major civilian airports use ASR
• Used in Approach and Departure
Control Facility
• Range of about 100 Miles
26. En Route Full Data Block
AAL278
330C
068 500
Position Symbol
Beacon Target
Aircraft
Identification
Ground Speed
Mode ‘C’ Altitude
X100
Leader Line
Computer
Identification
Number
Vector Line
Histories
27. Airport Surface Detection
Equipment
• Short range radar system to help
controller locate the locations of
moving, ground based aircraft and
vehicles
