Download presentation
Presentation is loading. Please wait.
Published byGervais Kelley Modified over 9 years ago
1
Qualcomm CDMA Technology
2
What is CDMA? Code Division Multiple Access –As opposed to TDMA (time-division) Strives to better utilize the radio spectrum by allowing multiple users to share the same physical channel Originally created by military during WWII to make it harder for enemies to intercept radio signals Qualcomm was first to commercialize the technology
3
GSM (TDMA) vs CDMA GSM divides the channel in frequency and time-domain (narrowband) CDMA uniquely encodes and transmits calls across entire spectrum –Spread Spectrum: can overlap multiple calls on the same channel GSM operates on four frequencies –Switch to determine handoff CDMA doesn’t assign a specific frequency to each user, all on SAME frequency –Soft handoff
4
Why does it matter? CDMA consistently provides better capacity for voice and data communication Analogy: a room full of people trying to have one-on-one conversations –TDMA: Each couple takes turns saying one sentence –CDMA: All speak at the same time but in different languages CDMA has traditionally been faster than GSM –Important for data transfer –Pressure for others to stay competitive
5
Lawsuits Qualcomm has the most patents on CDMA Ericsson, Nokia, Texas Instruments, Broadcom… Nokia –Thought Qualcomm wasn’t selling their technology to enough of the market –Qualcomm then sued Nokia for using their technology in new versions of GSM
6
Resolution? Most of the companies have multiple ongoing lawsuits Out of court settlements are being used as bargaining tools
Similar presentations
© 2024 SlidePlayer.com. Inc.
All rights reserved.