Internet of Things (IoT) Practice Exam

Which frequency bands does IEEE 802.11 utilize?

1. 900 MHz and 3.5 GHz

2. 2.4 GHz and 60 GHz

3. 5 GHz and 10 GHz

4. All of the above

The correct answer is: All of the above

The IEEE 802.11 standard, which pertains to wireless networking technology, primarily operates in several frequency bands, most notably those indicated in the correct answer. It utilises the 2.4 GHz band, which has been widely used for many years due to its ability to provide reasonable range and penetration through physical obstacles. Additionally, the technology employs the 5 GHz band, which offers higher data rates and less interference due to a lower number of devices operating within this range. Moreover, more recent advancements and extensions of the IEEE 802.11 standard, such as Wi-Fi 802.11ad, expand into even higher frequency bands, including 60 GHz. This band allows for extremely high data transfer rates over short distances, suitable for applications such as high-definition video streaming and virtual reality. Therefore, it is true that the standard operates within these frequency ranges, contributing to the classification that all listed frequency bands are utilized under various extensions of the IEEE 802.11 protocols. The inclusion of 900 MHz and 3.5 GHz in the incorrect options reflects frequencies used in other wireless technologies, such as LPWAN or specific communication systems, which are not part of the IEEE 802.11 standard.