Communications: directive radio wave systems and devices (e.g. – Aircraft collision avoidance system – With transponder
Patent
1993-07-23
1994-11-08
Barron, Jr., Gilberto
Communications: directive radio wave systems and devices (e.g.,
Aircraft collision avoidance system
With transponder
342 37, 342 38, G01S 1376, G01S 1391
Patent
active
053631099
ABSTRACT:
Conventional secondary radar systems use mechanically rotating antennas to radiate a concentrated beam that rotates in a horizontal plane. Data exchange between ground stations and airborne transponders can only take place if the aircraft is struck by the antenna lobe. The distance from the aircraft to the ground station is determined from the signal transit time. Directional information is derived from the antenna position. The secondary radar system according to the invention uses an omnidirectional antenna, so that data can be exchanged between ground station and aircraft at any time. To determine the position of the aircraft, interrogation signals are transmitted by a single active ground station such that the reply signal from a transponder falls within the common system time frame of the ground station. The times of arrival of the reply signals at different ground stations are then directly proportional to the distances from the aircraft to these ground stations.
Measurement errors caused by clock deviations are corrected by determining any deviation of the clocks of two ground stations from each other. To correct clock deviations, two interrogation/reply cycles are used in direct succession in opposite directions over a common transmission path. The two transmission periods will differ by twice the deviation of the clocks in the two ground stations. The measured deviation is used to correct the measured transit time values and/or to synchronize the clocks. Synchronization of several ground stations with a master station can be achieved by using successive interrogation/reply cycles between the master station and all other stations.
REFERENCES:
patent: 3388393 (1968-06-01), Graham et al.
patent: 3409889 (1968-11-01), Graham
patent: 3521279 (1970-07-01), Michnik
patent: 3705404 (1972-12-01), Chisholm
patent: 3766552 (1973-10-01), Hajduk
patent: 3943509 (1976-03-01), Pudsey
patent: 4197536 (1980-04-01), Levine
patent: 4319243 (1982-03-01), Vachenauer et al.
patent: 4768036 (1988-08-01), Litchford et al.
Aeronautical Telecommunications, (International Civil Aviation Organization Specification) Annex 10, vol. I, Part I, Chapter 3.8.2, pp. 47-54, (Apr. 1985), Canada.
Hofgen Gunter
Zeitz Rudiger
Alcatel Sel Aktiengesellschaft
Barron Jr. Gilberto
LandOfFree
Method of correcting measurement errors caused by clock deviatio does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Method of correcting measurement errors caused by clock deviatio, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Method of correcting measurement errors caused by clock deviatio will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-1785767