Method and apparatus for detecting and decoding transponder reply signals
US5387915A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Nov 16, 1993 |
| Grant date | Feb 7, 1995 |
| Priority date | — |
| Expiry date | Nov 16, 2013 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01S7/2886
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
Methods and apparatus for detecting and decoding transponder reply signals of the type having a plurality of associated time discrete pulses including two bracket pulses and a number of related data pulses that may have been transmitted at discrete data time intervals between the bracket pulses such that the signal content detected during the data time intervals corresponds to the reply signal data code, comprising receiver means for receiving the reply signals and producing in-phase (I), quadrature (Q) phase and video (V) signals for each received pulse; means for detecting received pulses and storing the I/Q/V signals in a first memory; means for storing in a second memory pointer values that correspond to the temporal location of pulse I/Q/V signals in the first memory; means for identifying, based on time of arrival (TOA) values, pairs of potential bracket pulses wherein each pair marks the beginning and end of a reply code; and processor means for 1) determining an angle of arrival (AOA) value for each detected pulse based on each pulse's I and Q signals, 2) selecting a reference pulse for each potential bracket pair based on relative amplitudes of the bracket pair, and 3) ide…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.