Comparison table
| Feature | GSM | UMTS | IS-95 | CDMA2000 |
|---|---|---|---|---|
| Technology | TDMA | W-CDMA | CDMA | CDMA |
| Generation | 2G | 3G | 2G | 3G |
| Year of First Use | 1991 | 2001 | 1995 | 2000 |
| Worldwide market share | 80% | 4% | 0.6% | 12% |
| Roaming | Worldwide | Worldwide | Limited | Limited |
| Signal quality/coverage area | Good coverage indoors on 850/900 MHz. Repeaters possible 35 km limit. | Smaller cells and lower indoors coverage due to 2100 MHz frequency | Unlimited cell size, low transmitter power permits large cells | Unlimited cell size, low transmitter power permits large cells |
| Frequency utilization/Call density | 0.2 MHz = 8 timeslots each timeslot can hold up to 2 calls through interleaving. | 5 MHz = 2 Mbps each call uses 1.8-12 kbps depending on chosen quality and audio complexity. | Comparable to UMTS | Comparable to UMTS |
| Battery life | Very good | Low | Low | Low |
| Handoff | Hard | Soft | Soft | Soft |
| Breathing | No | Yes | Yes | Yes |
| Intellectual property | No specific | No specific | Qualcomm | Qualcomm |
