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
7/00 Details of systems according to groups G01S13/00, G01S15/00, G01S17/00
G01S7/48 of systems according to group G01S17/00
G01S7/483 Details of pulse systems
G01S7/487 Extracting wanted echo signals; , e.g. pulse detection
G01S7/4876 by removing unwanted signals