Patent · US Expired

Median weighted tracking for spread-spectrum communications

US6983009B2 · kind B2 · utility

93Cited by
206References
3Claims
0Family size

Assignee

Inventor

Key dates

Filing dateJan 18, 2001
Grant dateJan 3, 2006
Priority date
Expiry dateMay 13, 2023

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY02D10/00
  • WIPO fieldDigital communication
  • WIPO sectorElectrical engineering

Abstract

An improvement for a method and system for tracking a spreading code, used in a code division multiple access (CDMA) system. An input signal has spread-spectrum modulation. The spreading code embedded in the spread-spectrum modulation has a plurality of chips. The input signal is sampled, and half-chip offset samples are formed from the sampled input signal. An even set of the half-chip offset samples are grouped into an early set of samples, and an odd set of the half-chip offset samples are grouped into a late set of samples. Each early set of samples is multiplied by the spreading code c(n+1), c(n+2), . . . , c(n+L), to generate a first plurality of products. L is approximately equal to the number of chips of delay between the earliest and latest multipath signals. A first plurality of sums and magnitudes are computed from the first plurality of products. The first plurality of magnitudes are summed to generate an early signal-energy value. Each late set of samples is multiplied by the spreading-code c(n−1), c(n−2), . . . , c(n−L), thereby generating a second plurality of products. A second plurality of sums and magnitudes are computed from the second plurality of products. The …

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