Identification technique for air traffic
US4442430A · kind A · utility
Inventor
Key dates
| Filing date | May 11, 1981 |
| Grant date | Apr 10, 1984 |
| Priority date | — |
| Expiry date | May 11, 2001 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01S13/782
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
The ITAT technique, embodied in ITAT hardware, provides a means to add additional operating modes to interrogator-transponder (beacon) systems in a relatively simple and economical manner. The technique permits the adding of special modulation to the normal pulse-coded transmissions for the purpose of providing a security identification code, or a digital wavefore enabling high processing gain, or both. Two similarly designed ITAT units are required; one for interrogator systems, and one for transponder systems. Both units simply connect between the respective system units and the system antennas. The ITAT units operate in two modes; "Normal" and "ITAT." In the normal mode, the units do not interfere with operation of the transponder-interrogator (beacon) system. In the ITAT mode, the units suppress the beacon system operating range by introducing attenuation between the interrogator unit (or transponder unit) and the antenna. In effect, normal operation is blocked during ITAT operation. In place of normal operation, the ITAT unit specially-modulates interrogator pulse-coded emissions to add special ITAT modulation. The ITAT receiver collocated with transponders detects and decodes…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.