Technology - Mobile 2 - 2G - IS-95 CDMA & GSM

Synopsis

By the late 1990s, two 2G mobile cellular systems were dominant in areas outside North America: IS-95 and GSM. GSM became the dominant technology and is also the basis for one of the two leading 3G technologies: UMTS W-CDMA. We discuss IS-95 CDMA and GSM, which together with IS-136 were the technologies that lead to the explosive worldwide adoption of mobile telephony.

Table of Contents

• 1. Synopsis
• 2. IS-95 CDMA
  • 2.1 Spread Spectrum to share radio resources
    • 2.1.1 Code Division
    • 2.1.2 CDMA advantages
  • 2.2 Forward Error Correction
  • 2.3 Compatibility with AMPS
  • 2.4 Simultaneous transmission and reception
  • 2.5 CDMA IS-95A/B Futures
• 3. GSM
  • 3.1 Frequencies
  • 3.2 GMSK Modulation
  • 3.3 Time and Frequency Division Multiplexing
  • 3.4 Hearing aid compatibility
    • 3.4.1 Pulsed transmission
    • 3.4.2 Standards and regulation
  • 3.5 Timing and power control
  • 3.6 Distance limits
  • 3.7 Voice compression
  • 3.8 Modulation and interleaving
  • 3.9 Frequency Hopping
• 4. Related reports

• Table seq Table \* Arabic 1 – GSM Radio Frequencies