From GSM to LTE: An Introduction to Mobile Networks and Mobile Broadband

6.9 Comparison of Wireless LAN and UMTS

In the early days of Wi-Fi and UMTS, the potential competition between the two wireless technologies was often debated. Today, both technologies have evolved and both have found their respective usage domains.

While presently Wi-fi is mostly used at homes and in offices and also as a hotspot technology in public places such as airports and hotels, UMTS has evolved with its HSPA extensions to be a wide area high-speed connectivity technology. To demonstrate where UMTS and Wi-Fi compete and cooperate today, the following sections describe the use of the two systems for Internet connectivity outside the homes and offices.

When comparing peak datarates of Wi-Fi and UMTS outside the homes and offices, a significant difference can be observed at first. While some hotspots still use the 802.11b standard today with peak datarates of 11 Mbit/s on the physical layer, many have already been upgraded to 802.11g and hence their theoretical peak datarate is 54 Mbit/s. In the future, further peak datarate improvements can be made with 802.11n and WMM QoS extensions can be used to prioritize data streams for applications such as VoIP. As has been shown in this chapter, peak datarates of 5, 24 and 100 Mbit/s can be reached at the application layer. This compares to current physical layer datarates of 3G networks between 3 and 20 Mbit/s and achievable datarates in practice between 2 and 8 Mbit/s, and even more under very favorable transmission conditions. ...