Wi-Fi (Wireless) Card Recommendations

This is a webpage to explain the benefits of 2.4 and 5 GHz (dual band) wireless cards

When purchasing a Windows laptop, check that your system configuration includes a Wi-Fi card that will operate in both the 2.4 and 5 GHz radio frequencies. Laptop computer manufacturers often obscure the Wi-Fi radio specifications or offer a less capable card limited to operating in the 2.4 GHz radio frequency only. Don't fall prey to manufacturers that boast high performance because their Wi-Fi radio supports the "n" standard. The "n" designator alone does not indicate that the Wi-Fi operates in both frequencies.

When configuring your laptop, confirm that the manufacturer explicitly states the Wi-Fi radio has dual-band support in both 2.4 and 5 GHz radio frequencies or the specifications specifically include one of the following, Wi-Fi a/b/g/n, Wi-Fi ac/b/g/n, 802.11 a/b/g/n, or 802.11 ac/b/g/n. The presence of the letter "a" or "ac" indicates the radio operates in the 5 GHz frequency; this is the performance differentiator. The letters "b/g" inform you the radio operates in the 2.4 GHz frequency--when combined together you are assured of dual-band support.

Here is the lowdown of why it's important to spend a little extra time and money to configure your Windows laptop for optimal Wi-Fi performance.

Unlike wired networks, which allow your computer to transmit and receive on a dedicated private copper cable, your Wi-Fi radio must transmit over-the-air using a shared radio frequency. In plain terms, your wireless transmissions share the same radio frequency with other wireless devices trying to transmit data at the same time. Effectively, only one transmission can take place at a time in a given radio channel. Wi-Fi radios limited to working in the 2.4 GHz frequency support only three non-overlapping radio channels. In comparison, radios operating in the 5 GHz radio frequency support over 22 non-overlapping radio channels.

On UofL’s urban campuses, the Wi-Fi air space is littered with foreign networks/devices operating in the 2.4 GHz frequency. If your laptop only supports this single frequency, it must compete among the three available radio channels with hundreds of Apple iPhones, ATT Wireless, and many other foreign networks/devices that operate exclusively in the 2.4 GHz frequency. If you want to avoid this radio frequency competition, you need a dual-frequency Wi-Fi card.

With a dual-band card, when connected to UofL's ulsecure network, you take advantage of ulsecure’s centralized controllers with the intelligence to balance the Wi-Fi air-space ensuring that the maximum number of radio channels are made available to your wireless device. This optimization greatly helps combat interference from foreign networks to improve your wireless performance.

NOTE: Apple laptops are sold exclusively with dual-band Wi-Fi radios, so there are no Wi-Fi configurations to check at purchase time.

If you are not sure if the Windows laptop you are considering is single-band or dual-band, look under the laptop's wireless device/Wi-Fi card specifications on the box, label, or product Web page.

Here is an online example:

Example of where to find dual-band specifications.

You are looking for 802.11a/b/g/n, as pictured, or 802.11ac/b/g/n Anything else will not be able to take full advantage of UofL’s network speed.

If you are having trouble finding this information, contact the laptop manufacturer (Dell, HP, Lenovo, etc.) or contact the UofL Help Desk at helpdesk@louisville.edu or 502-852-7997.