Patent · US Expired

Apparatus and method for signal identification

US5696789A · kind A · utility

16Cited by
4References
22Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMar 6, 1995
Grant dateDec 9, 1997
Priority date
Expiry dateMar 6, 2015

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04B1/707
  • WIPO fieldTelecommunications
  • WIPO sectorElectrical engineering

Abstract

A novel code division multiple access (CDMA) system and apparatus is provided which permits a plurality of encoded modulated data messages to be transmitted simultaneously on the same channel in one frequency band as a composite CDMA signal. An identification signal is generated and spread by a spreading signal having a duty cycle less than fifty percent to produce a combined signal which is transmitted to a receiver having a tapped delay with a plurality of taps each of which produce a replica of the received combined signal delayed by an odd multiple of the duty cycle of the spreading signal. Each of the replica signals is multiplied by a predetermined weighted value to produce weighted delayed signals and a controller responsive to the received combined signal, is employed for controlling individual weighted delayed signals which are then combined to suppress the spreading signal leaving the identification signal.

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