1 / 6

Qualcomm

Qualcomm. CDMA Technology. 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

sai
Download Presentation

Qualcomm

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript


  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

More Related