The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Oct. 13, 1998
Filed:
Jun. 16, 1995
Bertrand Thebault, Montauban de Bretagne, FR;
Philippe Sehier, Lavallois Perret, FR;
Alcatel Telspace, Nanterre Cedex, FR;
Abstract
A search method for acquisition of time synchronization between a spreading sequence of a receiver and a spreading sequence of a transmitter, the receiver receiving a spread signal and demodulating the signal using the spreading sequence of the receiver includes a test step consisting in measuring the energy of the demodulated signal by integrating the demodulated signal during a time interval Tobs.sub.i and comparing that energy with a threshold value to determine if the threshold value is exceeded, for a given hypothesis as to the time shift between the spreading sequences, and modifying the time shift hypothesis if the threshold value is not exceeded and incrementing the value of a counter. Steps a and b are repeated until the value of the counter reaches a predetermined value. When the predetermined value is reached, the time interval Tobs.sub.i is replaced with a time interval Tobs.sub.i+1, with Tobs.sub.i+1 =m.Tobs.sub.i and m>1, and the process resumes at step a replacing Tobs.sub.i with Tobs.sub.i+1. The process ends when the predetermined value has been reached a predetermined number of times. The invention applies to the reception of spread signals with an unknown signal-to-noise ratio.