§
Luxuse
Patent Intelligence
Sign In
← Back to Patent Explorer
US5157615A Expired / Lapsed US ⏱️ 0.0 years remaining

Aircraft traffic alert and collision avoidance device

Assignee: Ryan International Corp
•
Filing: 1991-12-31
•
Granted: 1992-10-20
•
Expires: 2011-12-31
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract A passive aircraft Traffic alert and Collision Avoidance Device (TCAD) is based on sensing and responding to transponder replies of other aircraft to SSR interrogations. In order to avoid masking other aircraft replies by the host transponder TCAD repeatedly and randomly suppresses the host transponder and simultaneoulsly listens for other aircraft replies. Suppression on each occasion is effective for an equal and predetermined duration which is much longer than a typical replay, in a preferred embodiment the suppression/listen duration is 725 μs. In this embodiment the time between successive suppression/listen occasions is random between 725 μs. and 5.025 ms. with an average value of about 2.9 ms. Digital signal processing is used to detect and discard garbled or overlapping replies. Each valid reply, exhibiting a minimum pulse amplitude, is decoded and correlated with a calibrated range parameter and given a time tag. Successive replies which match to within predetermined criteria in time and calibrated range are merged to track the positional relation between the host and other aircraft. The positional relation between other aircraft and the host are evaluated via a priority table in terms of relative altitude and range to locate that craft which poses the highest threat to the host. Parameters of such a craft are displayed. In the event a craft penetrates a shield of programmable size an audible alert is sounded. TCAD provides for shields for each of a plurality of flight regimes, such as terminal, standard and enroute.

Inventors

  • 👤 William C. Brodegard
  • 👤 Dean E. Ryan
  • 👤 Paul A. Ryan

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-26 13:40
CPC Classifications
G; G01; G01S; G01S13/00; G01S13/74; G01S13/76; G01S13/767; G01S13/88; G01S13/93; G01S13/933

Claims Analysis

Total Claims: 7
Claim 1
Independent Claim 127 words
In a proximity warning system based solely on receipt, at an own aircraft, of replies by transponders of other aircraft and own aircraft altitude, a method of selectively displaying data to an operator comprising the steps of: a) establishing a threat prioritization table containing a numeric threat value based on distance and altitude separations between own and other aircraft, b) establishing a list of other aircraft, each aircraft on said list associated with parameters including altitude and distance separation, said parameters based on replies of transponders of said other aircraft, c) determining from the threat prioritization table a numeric threat value for the other aircraft on the list, d) driving a display with data selected from the list in an order determined from the numeric threat value.
Claim 2
Dependent Claim 127 words
In a proximity warning system based solely on receipt, at an own aircraft, of replies by transponders of other aircraft and own aircraft altitude, a method of selectively displaying data to an operator comprising the steps of: a) establishing a threat prioritization table containing a numeric threat value based on distance and altitude separations between own and other aircraft, b) establishing a list of other aircraft, each aircraft on said list associated with parameters including altitude and distance separation, said parameters based on replies of transponders of said other aircraft, c) determining from the threat prioritization table a numeric threat value for the other aircraft on the list, d) driving a display with data selected from the list in an order determined from the numeric threat value.
Claim 3
Dependent Claim 30 words
A method as recited in claim 1 wherein said threat prioritization table is arranged to contain numeric threat values which increase with increasing separation between own aircraft and other aircraft.
Claim 4
Dependent Claim 43 words
A method as recited in claim 2 wherein said display is normally driven by data associated with that other aircraft having the lowest threat value and wherein the operator can command display of data associated with a different one of the other aircraft.
Claim 5
Dependent Claim 67 words
A method as recited in claim 1 wherein said step of establishing the thread prioritization table comprises the steps of: a1) dividing airspace surrounding the host aircraft into several regions as a function of altitude and distance separation; and a2) prioritizing each of said regions by assigning threat value ranges to each said region as a function of altitude and distance separation pairs contained within the ranges.
Claim 6
Dependent Claim 39 words
A method as recited in claim 4 which comprises the further step of providing thread values in each said region, for different distance and altitude separation pairs, so that each threat value is different from all other threat values.
Claim 7
Dependent Claim 20 words
A method as recited in claim 5 wherein threat values are assigned so that threat values increase with increasing separation.

References Cited (Backward Citations)

US4063073A Cited
US4797839A Cited
US4646244A Cited
US4947350A Cited
US4839658A Cited
US4823272A Cited
US5058024A Cited
US5077673A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1995-10-20 1996-04-20 1996-10-20 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1999-10-20 2000-04-20 2000-10-20 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2003-10-20 2004-04-20 2004-10-20 $7700.00 Window Closed / Lapsed

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag