Patent · US Expired

Interference signal cancellation system

US6002727A · kind A · utility

64Cited by
3References
6Claims
0Family size

Assignee

Inventor

Key dates

Filing dateOct 16, 1997
Grant dateDec 14, 1999
Priority date
Expiry dateOct 16, 2017

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04B1/7115
  • WIPO fieldTelecommunications
  • WIPO sectorElectrical engineering

Abstract

The interference signal cancellation system of the invention has: usual CDMA demodulators respectively disposed for codes, each of the CDMA demodulators having a matched filter 105 and an identifier 107; and a likelihood calculator 108 for each of the demodulators. The apparatus further has: a buffer 103 which stores provisional decision values; another buffer 109 which stores likelihoods; an order determining device 110 which determines an order in accordance with the likelihoods; a respreading device 111 which performs respreading in accordance with the determined order; a delay device 102 which delays a received signal; and a subtractor 112 which subtracts a result of the respreading from the delayed data. For each symbol, the largest likelihood is selected, and a replica is generated by using it. A desired performance is attained by performing one provisional decision and one demodulation. Therefore, computational complexity is reduced and realization is facilitated.

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