When choosing wireless networking hardware for your new computer, the choices available can sometimes be overwhelming. Not only must you choose the right card, but you need to ensure you have the right antenna for your needs.
The specific card and antenna combination necessary will generally be based on 3 key factors: what you will be using the network-connected device for, what kind of wireless network you are connecting to and how far away you are from the source signal. If you know the answers to these basic questions, choosing the right network solution can be fairly easy.
Selecting a Wireless Card
The first step in choosing a wireless card is making sure it is compatible with your computer and operating system. Most wireless cards plug into Mini PCIe and M.2 Key-E for Wi-Fi or M.2 Key-B for Cellular connectivity. If your computer has this slot then the card will be electromechanically compatible. Most cards today are PCIe based, so ensure you’re buying a card and motherboard that has the corresponding connections required. Some cards use PCIe for the Wi-Fi and the USB for Bluetooth connectivity, so when choosing a card that supports both, be sure the slot you are inserting it to supports both PCIe and USB signaling. Next, you must make sure there are drivers available for that card and the operating system you plan to use (Windows for example). At OnLogic, we make sure to choose cards that have a broad range of compatibility, with most of our wireless cards support both Linux and Windows operating systems.
Once you know the card will work with your computer, you need to ensure it’s right for the kind of network you’ll be connecting to. Wi-Fi cards are broken down to the technology they have, for example, the newest cards feature W-Fi 6. The legacy terms for wireless networking cards are broken down into different variants, represented by 802.11 (an IEEE specification) followed by a letter(s). For example, the modern wireless standard is 802.11ax (Now known as Wi-Fi 6) . Previous versions included “b”,”g”,”n” and “a”. Except for “a”, wireless networks are cross compatible, meaning a “g” enabled card can connect to an “n” network (provided that function is not disabled by your router or IT team). However, if you want the full bandwidth and features of the newest networks, you need a matching wireless card.
Wi-Fi naming has recently been updated to define the generation. Currently the newest generation is Wi-Fi 6 which corresponds to the IEEE definition of 802.11ax. You can find the newest generations of Wi-Fi and what they originally were called on the Wi-FI alliance website: https://www.wi-fi.org/discover-wi-fi
Also important for some customers is the brand of the chipset running the card. Examples of these include Intel, Broadcom and Qualcomm Atheros. The manufacturer of the card doesn’t necessarily indicate specific features, many times it comes down to experience and personal preference and what your application requires.
The last thing to check is if the card includes Bluetooth onboard. Although most modern wireless cards come with it, some still don’t. Bluetooth is great for connecting wireless peripherals and other devices to your computer. Like Wi-Fi, Bluetooth has multiple versions available , with the most current version being 5.2. Bluetooth is also backwards compatible, meaning all versions can interconnect with each other. However, as with wireless internet, you lose some features doing this.
Which Wireless Antenna Do I Need?
The internal construction of the antenna is crucial for optimal performance.
With antennas, there are two pieces involved; a pigtail cable which goes from the internal wireless card to the exterior of the chassis, and the actual antenna. When you add wireless hardware to any Logic Supply system, the pigtail is included by default. What isn’t included, and what you’ll need to choose, is the external antenna.
One of the most important antenna specs to consider is gain. Gain refers to how well the antenna amplifies the signal it’s receiving. This is measured in decibels(dB). The higher the dB, the better the antenna will perform in strengthening weak signals. The typical range for screw-on antennas is 2-7dB.
Single Band vs Dual Band Antennas
Antennas are also classified by what frequency bands they are tuned to amplify. Any wireless technology has a frequency band that it needs to operate within. Bluetooth operates in the 2.4Ghz band, as do legacy Wireless networks . Wi-Fi 4 and beyond may also operate in the 5Ghz band. When buying an antenna, you need to ensure these bands are covered. At OnLogic we sell single band and dual band versions of our antennas. Single band covers just 2.4Ghz while a dual band antenna covers 2.4Ghz and 5Ghz bands. The good news with frequencies is that they don’t change, meaning your IT department or router can’t inadvertently choose to operate outside of those two bands.
One question we get often is, if Bluetooth and Wireless are operating in the same frequency range, won’t they interfere? This is a great question, but in reality, the two aren’t actually operating at the exact same frequencies. Actually, the 2.4Ghz range has several separate frequency bands or channels that devices can use, and many devices dynamically change channels to help prevent interference and increase performance. A 2.4Ghz antenna can cover all of these frequencies, known as channels. Additionally Wi-Fi 6 introduces OFDMA (Orthogonal Frequency Division Multiple Access) where a specific channel can split the bandwidth evenly across up to 30 users without expecting interference. This is great in applications where many users are crowded in one area and don’t necessarily need all of the channel’s bandwidth.
What Size Antenna, and How Many?
So, what about the physical size of the antenna? You’ll want to make sure that the size of the antenna works in the footprint in which the computer will be operating. Size doesn’t necessarily affect the performance of the antenna, so always check the dB rating of the antenna you choose.
The last thing to consider when selecting antennas is deciding how many you need. Generally speaking, wireless cards have two antenna connections and you should use both. Although it is possible to get away with one antenna if the router or signal source is close enough, you should usually stick to the number of antennas recommended by the card manufacturer.
Choosing the right wireless solution can be easy when following the above guidelines, and knowing your usage situation goes a long way to ensuring you choose the ideal hardware. If you have questions about which wireless card and antenna combination would best suit your needs, call OnLogic’s highly capable technical team who will quickly identify the right wireless solution for your unique project.
Note: This blog was originally posted on February 17, 2015. It was updated for content on August 11, 2020.