US3997898A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Channeling method and apparatus
Assignee: International Telephone and Telegraph Corp
•
Filing: 1975-05-05
•
Granted: 1976-12-14
•
Expires: 1995-05-05
Abstract
Abstract This relates to a channeling scheme for introducing a new service in the TACAN frequency band which can operate independently of the conventional TACAN system or in conjunction with it. Specifically, the new service is that of providing precision DME for a microwave landing system and for allowing existing TACAN airborne sets, when equipped with an adapter, to utilize new MLS ground beacons. In one channeling scheme, interrogations occur in frequency bands adjacent the standard TACAN interrogation band, and ground transmissions occur in frequency bands presently occupied by X mode reply signals. In a second scheme, which contemplates the use of standard airborne equipment provided with an adapter, interrogations occur within the conventional TACAN interrogation band, and replies occur in the bands now occupied by X mode reply signals.
Inventors
- 👤 Jesse S. LeGrand
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 05:06
CPC Classifications
G; G01; G01S; G01S13/00; G01S13/74; G01S13/82; G01S13/84
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
53 words
A method of responding to X mode and Y mode interrogation signals wherein said interrogation signals have frequencies within the first and fourth quarter of the TACAN frequency band, comprising the step of transmitting X and Y mode phase coded reply signals in the first and fourth quarter of the TACAN frequency band.
Claim 2
Independent Claim
53 words
A method of responding to X mode and Y mode interrogation signals wherein said interrogation signals have frequencies within the first and fourth quarter of the TACAN frequency band, comprising the step of transmitting X and Y mode phase coded reply signals in the first and fourth quarter of the TACAN frequency band.
Claim 3
Independent Claim
51 words
A method of interrogating a transponder wherein said transponder is of the type which replies to X and Y mode interrogations within the standard TACAN frequency band comprising the step of transmitting X and Y mode phase coded interrogation signals within the first and fourth quarter of the TACAN frequency band.
Claim 4
Independent Claim
51 words
A method of interrogating a transponder wherein said transponder is of the type which replies to X and Y mode interrogations within the standard TACAN frequency band comprising the step of transmitting X and Y mode phase coded interrogation signals within the first and fourth quarter of the TACAN frequency band.
Claim 5
Independent Claim
85 words
A method of determining distance between an interrogator and a transponder comprising: transmitting from an interrogator X and Y mode interrogation signals within the TACAN frequency band; receiving said interrogation signals at a transponder; transmitting from said transponder and in response to said interrogation signals X and Y mode phase coded reply signals in the first and fourth quarter of the TACAN frequency band; receiving said reply signals at said interrogator; and processing said reply signals to determine distance between said interrogator and said transponder.
Claim 6
Independent Claim
85 words
A method of determining distance between an interrogator and a transponder comprising: transmitting from an interrogator X and Y mode interrogation signals within the TACAN frequency band; receiving said interrogation signals at a transponder; transmitting from said transponder and in response to said interrogation signals X and Y mode phase coded reply signals in the first and fourth quarter of the TACAN frequency band; receiving said reply signals at said interrogator; and processing said reply signals to determine distance between said interrogator and said transponder.
Claim 7
Dependent Claim
29 words
A method according to claim 3 wherein said transmitting from an interrogator includes transmitting phase coded interrogation signals within the first and fourth quarter of the TACAN frequency band.
Claim 8
Dependent Claim
42 words
A method according to claim 4 wherein interrogation signals in said first quarter are responded to with reply signals in said fourth quarter and wherein said interrogation signals in said fourth quarter are responded to with reply signals in said first quarter.
Claim 9
Dependent Claim
28 words
A method according to claim 3 wherein said transmitting from an interrogator includes transmitting conventional TACAN interrogations within the second and third quarter of the TACAN frequency band.
Claim 10
Dependent Claim
42 words
A method according to claim 5 wherein interrogation signals in said second quarter are responded to with reply signals in said fourth quarter and wherein said interrogation signals in said second quarter are responded to with reply signals in said first quarter.
Claim 11
Independent Claim
145 words
An apparatus for use with airborne equipment of the type which transmits Gaussian pulse pair interrogation signals in the TACAN frequency band to a transponder, and wherein normally said transponder generates pulse pair reply signals in response to said interrogations which are received and processed by said airborne equipment, and wherein said pulse pair reply signals are replaced by phase coded interrogation signals having a frequency different from the normal pulse pair replies, said airborne equipment including a transmitter, a receiver, an interrogator and an antenna, said apparatus comprising: means for receiving said phase coded reply signal; means for converting said phase coded reply signal to a pulse pair signal; and means for altering the frequency of said reply signal to correspond to the frequency of a standard pulse pair reply signal such that said altered reply signal may be processed by said airborne equipment.
Claim 12
Independent Claim
145 words
An apparatus for use with airborne equipment of the type which transmits Gaussian pulse pair interrogation signals in the TACAN frequency band to a transponder, and wherein normally said transponder generates pulse pair reply signals in response to said interrogations which are received and processed by said airborne equipment, and wherein said pulse pair reply signals are replaced by phase coded interrogation signals having a frequency different from the normal pulse pair replies, said airborne equipment including a transmitter, a receiver, an interrogator and an antenna, said apparatus comprising: means for receiving said phase coded reply signal; means for converting said phase coded reply signal to a pulse pair signal; and means for altering the frequency of said reply signal to correspond to the frequency of a standard pulse pair reply signal such that said altered reply signal may be processed by said airborne equipment.
References Cited (Backward Citations)
US3076190A
Cited
US3825929A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1979-12-14 | 1980-06-14 | 1980-12-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-12-14 | 1984-06-14 | 1984-12-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-12-14 | 1988-06-14 | 1988-12-14 | $7700.00 | Window Closed / Lapsed |