Which wireless standard has bandwidth up to 54 Mbps and signals in a regulated frequency spectrum around 5 GHz?

Which wireless standard has bandwidth up to 54 Mbps and signals in a regulated frequency spectrum around 5 GHz?

• A. 802.11b
• B. 802.11i
• C. 802.11a
• D. 802.11g

Answer: (C)

The essential idea here is how different Wi‑Fi standards use different frequency bands and deliver different maximum data rates. The 5 GHz band is used by the 802.11a standard, which was designed to achieve higher speeds with less interference than the older 2.4 GHz bands. It uses OFDM modulation to reach up to 54 Mbps and operates in the regulated 5 GHz spectrum, which, in many regions, offers more available channels and cleaner air compared with 2.4 GHz. Other options operate in the 2.4 GHz band or focus on security rather than speed. For example, the older 802.11b standard runs at up to 11 Mbps in 2.4 GHz. The 802.11g standard also uses 2.4 GHz and can reach 54 Mbps, but not in the 5 GHz band. The 802.11i standard is about security (WPA2), not a data-rate or frequency specification. So, the standard that matches both the 54 Mbps capability and the 5 GHz spectrum is 802.11a.

The essential idea here is how different Wi‑Fi standards use different frequency bands and deliver different maximum data rates. The 5 GHz band is used by the 802.11a standard, which was designed to achieve higher speeds with less interference than the older 2.4 GHz bands. It uses OFDM modulation to reach up to 54 Mbps and operates in the regulated 5 GHz spectrum, which, in many regions, offers more available channels and cleaner air compared with 2.4 GHz.

Other options operate in the 2.4 GHz band or focus on security rather than speed. For example, the older 802.11b standard runs at up to 11 Mbps in 2.4 GHz. The 802.11g standard also uses 2.4 GHz and can reach 54 Mbps, but not in the 5 GHz band. The 802.11i standard is about security (WPA2), not a data-rate or frequency specification.

So, the standard that matches both the 54 Mbps capability and the 5 GHz spectrum is 802.11a.