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Publication of BE677066ApublicationCriticalpatent/BE677066A/xx
G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
G01S15/00—Systems using the reflection or reradiation of acoustic waves, e.g. sonar systems
G01S15/02—Systems using the reflection or reradiation of acoustic waves, e.g. sonar systems using reflection of acoustic waves
G01S15/04—Systems determining presence of a target
G—PHYSICS
G01—MEASURING; TESTING
G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
G01S7/00—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00
G01S7/52—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00 of systems according to group G01S15/00
G01S7/523—Details of pulse systems
G01S7/526—Receivers
G01S7/529—Gain of receiver varied automatically during pulse-recurrence period
G—PHYSICS
G08—SIGNALLING
G08G—TRAFFIC CONTROL SYSTEMS
G08G1/00—Traffic control systems for road vehicles
G08G1/01—Detecting movement of traffic to be counted or controlled
G08G1/04—Detecting movement of traffic to be counted or controlled using optical or ultrasonic detectors
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Engineering & Computer Science
(AREA)
Physics & Mathematics
(AREA)
General Physics & Mathematics
(AREA)
Radar, Positioning & Navigation
(AREA)
Remote Sensing
(AREA)
Computer Networks & Wireless Communication
(AREA)
Acoustics & Sound
(AREA)
Measurement Of Velocity Or Position Using Acoustic Or Ultrasonic Waves
(AREA)