Patent · US Expired

CDMA communications and geolocation system and method

US5506864A · kind A · utility

313Cited by
25References
6Claims
0Family size

Assignee

Inventor

Key dates

Filing dateSep 23, 1994
Grant dateApr 9, 1996
Priority date
Expiry dateSep 23, 2014

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04W88/08
  • WIPO fieldTelecommunications
  • WIPO sectorElectrical engineering

Abstract

A spread-spectrum CDMA communications system for locating remote units, and for communicating message data between a plurality of remote units and a base station. The spread-spectrum CDMA communications system includes a plurality of base stations and a plurality of remote units. A base station has a spread-spectrum modulator for spread-spectrum processing the message data, and a transmitter for transmitting the spread-spectrum processed-message data, combined with a generic-chip-code signal, from the base station to a remote unit. The base station also has an antenna, and spread-spectrum detectors for recovering message-data communicated from the remote-units. A remote-unit has an antenna, and a detector coupled to the antenna for recovering data communicated from the base station. The detector includes a spread spectrum demodulator. Also, the remote unit has a device for converting the format of the data into a form suitable for communicating over radio waves, a spread spectrum modulator and a transmitter. The base station has a range circuit, which comparers the generic-chip-code signal generated at the base station with the generic-chip-code signal received from the remote unit…

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