Issue link: https://resources.mouser.com/i/1313794
19 Qorvo 2020 Wi-Fi Versus Bluetooth ® (and Now Zigbee) At the same time, the battle between Wi-Fi and 3G unfolded, another battle emerged. Several companies that were suppliers to the telephone industry (notably Ericsson and Nokia) saw another usage for ISM bands—to improve phone connectivity when connecting to a hotspot for information downloads and when connecting wireless headsets and other devices to the phone. To create a standard for type of phone connectivity, the Bluetooth® SIG (Special Interest Group) was formed, with companies as members (as opposed to the engineer members of IEEE 802.11). Fairly soon, the Bluetooth® SIG echoed 3GPP in declaring Wi-Fi redundant and telling the market Wi-Fi would soon disappear. Again, not so much. After a few years, it became clear that Wi-Fi and Bluetooth® had separate, defined application domains—Wi-Fi for "networking" and Bluetooth® for "peripheral connectivity." Since then, many devices have emerged with both Wi-Fi and Bluetooth®–Wi-Fi for high- speed networking and Bluetooth® for connecting devices. For a while, there was an effort to make Bluetooth® part of IEEE, but their organizational and membership differences drove them apart. Interestingly, there is a sequel of this battle in the works today. Zigbee, the low-power variant of Wi-Fi (based on IEEE 802.15.4) is under threat from Bluetooth® Low Energy, the low-power variant of Bluetooth®. The Bluetooth® SIG is developing a networking variant (Bluetooth® Mesh) that is supposed to compete with Zigbee. Looking at the early proposals, however, it seems that considerable complexity would need to be added to Bluetooth® Low Energy to achieve what is already available with Zigbee. We will have to wait and see how this plays out. Spectrum Availability The evolution of these wireless technologies was made possible by growing amounts of radio spectrum made available by the worlds' regulatory authorities. Figures 2 and 3 give rough indications of the major technologies and frequency bands involved. At the 2019 World Radio Conference, significant new allocations are expected for Wi-Fi and 5G to support the increasing demands for wireless data communications. The exact details of spectrum availability and usage conditions is beyond the scope of this document. Figure 2 Current and expected frequency bands for major wireless technologies Figure 3 Evolution of spectrum availability for major wireless technologies (approximate frequency bands and dates)