Pascal G Renucci

US Patent:

7324617, Jan 29, 2008

Filed:

Mar 24, 2003

Appl. No.:

10/395992

Inventors:

Debarag Narayan Banerjee - Sunnyvale CA, US
Pascal Gilles Renucci - Sunnyvale CA, US
Karim Nassiri Toussi - Belmont CA, US

Assignee:

National Semiconductor Corporation - Santa Clara CA

International Classification:

H04B 7/10

US Classification:

375347

Abstract:

A mobile device detects downlink transmit diversity. Slot and frame timing knowledge and a downlink scrambling code are applied to pilot and synch channels of the signal. An algorithm suited for the diversity case and an algorithm suited for the non-diversity case are utilized. The output of the diversity algorithm is compared to the output of the non-diversity algorithm. The output yielding the highest energy determines whether downlink transmit diversity is applied. The detection algorithms used in both the diversity and non-diversity cases use phasors to indicate the phase difference between two channels. This phase difference is the basis for determining diversity usage.