Patent · US Expired

Spread spectrum digital transmission system using low-frequency pseudorandom encoding of the wanted information and spectrum spreading and compression method used in a system of this kind

US5546423A · kind A · utility

11Cited by
6References
8Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJun 8, 1994
Grant dateAug 13, 1996
Priority date
Expiry dateJun 8, 2014

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04K1/02
  • WIPO fieldTelecommunications
  • WIPO sectorElectrical engineering

Abstract

A spread spectrum digital transmission system using low-frequency pseudorandom encoding of desired information, and a spectrum spreading and compression method used in such a system. In a transmitter in the system, each block of a digital signal to be transmitted is combined with a sample obtained from a low-frequency pseudorandom generator. The resulting various combinations are converted into orthogonal or quasi-orthogonal sequences which are modulated and transmitted to a receiver. The receiver demodulates the signal received and combines each sequence with a sample identical to that used for the low-frequency coding at the transmitter to recover the various blocks of the transmitted signal. Hence, low frequency spectrum spreading of a signal to be transmitted is achieved.

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