Patent · US Expired

Transdigitizer for relaying signals from global positioning system (GPS) satellites

US4622557A · kind A · utility

66Cited by
8References
6Claims
0Family size

Assignee

Inventor

Key dates

Filing dateOct 31, 1984
Grant dateNov 11, 1986
Priority date
Expiry dateOct 31, 2004

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG01S19/14
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

The reception, downconversion and retransmission of the 1575.42 MH.sub.z Global Positioning System (GPS) satellite signal is accomplished by the following. First, an RF stage comprising of an antenna, filter and preamplifier receiver, filters and amplifies the 1575.42 MH.sub.z signals. Following the RF stage, a converter stage, consisting of a bandpass filter, converts the GPS signal to a lower frequency. Then, an Intermediate Frequency (IF), comprising an IF amplifier, multiplier, bandpass filter and limiter further amplifies and filters the signals to remove the effects of the signals. A final downconverter converts the signal to a base band frequency and in a zero crossing detector the signal is amplified and 1 bit quantized. Finally, a local oscillator controls a frequency synthesizer to latch the signal from the zero crossing detector in a flip flop, which in turn is used to control a quadraphase monitor, whose signals are amplified and transmitted out the transmit antenna.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.