Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Publication of NL9568CpublicationCriticalpatent/NL9568C/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
G01S1/00—Beacons or beacon systems transmitting signals having a characteristic or characteristics capable of being detected by non-directional receivers and defining directions, positions, or position lines fixed relatively to the beacon transmitters; Receivers co-operating therewith
G01S1/72—Beacons or beacon systems transmitting signals having a characteristic or characteristics capable of being detected by non-directional receivers and defining directions, positions, or position lines fixed relatively to the beacon transmitters; Receivers co-operating therewith using ultrasonic, sonic or infrasonic waves
Landscapes
Engineering & Computer Science
(AREA)
Computer Networks & Wireless Communication
(AREA)
Physics & Mathematics
(AREA)
General Physics & Mathematics
(AREA)
Radar, Positioning & Navigation
(AREA)
Remote Sensing
(AREA)
Measurement Of Velocity Or Position Using Acoustic Or Ultrasonic Waves
(AREA)
Building Environments
(AREA)
Electrostatic, Electromagnetic, Magneto- Strictive, And Variable-Resistance Transducers
(AREA)