What is MU-MIMO? Why your next WiFi router should have MU-MIMO?


This may not be so important if you use Ethernet rather than WiFi, but think outside the box. Smartphones, tablets, Kindle, cameras, child monitors and many other devices only support Wi-Fi. With so many Wi-Fi enabled devices, MU-MIMO is even more important.

MU-MIMO stands for Multi-User, Muliple Input, Multiple Output. If you do not understand well, do not worry, this technology is simpler than the looks and benefits it brings is well worth knowing.

Wi-Fi prior to MU-MIMO

To understand the benefits of MU-MIMO, first of all understand how the traditional router operates. If you already know then you can skip and read later.

Prior to MU-MIMO, the wireless router was primarily based on the SU-MIMO technology, first introduced as the 802.11n Wi-Fi standard in 2007 and stands for Single-User, Multiple Input, Multiple Output. SU-MIMO allows the router to simultaneously send and receive data to and from a single device (Multiple Input/Output). Prior to SU-MIMO, routers can only send or receive at a time.

SU-MIMO has significantly increased the wireless data rate, but still has a big minus point, it can only send/receive data with one device at a time (Single-User). If your router is old or cheap, chances are it will only be able to operate on one device at a time.

The difference between SU-MIMO and MU-MIMO

This may not sound right. Currently, you may be using your computer, laptop, smart TV, and some phones, tablets, while they both use Wi-Fi at the same time. What is “one device at a time”?

Think of the SU-MIMO router as a dealer. There are 4 players on the table but the one who plays can only play for one person at a time. Imagine that each card is a data packet, which means that the SU-MIMO router will have to connect to each device in turn and quickly switch to another device, which means that they are connected at the same time. There will be a huge bottleneck because it’s just the 802.11ac Wi-Fi standard.

802.11ac Wi-Fi (Wave 1 and Wave 2)

There are a few things you need to know about MU-MIMO, which is the 802.11ac Wi-Fi standard. If you already know about the AC router, then read on.

802.11ac Wi-Fi standard is expected in 2013, six years after 802.11n. The new specs offer some improvements, speed up the Wi-Fi max but not all the changes immediately. The manufacturer has brought different aspects of 802.11ac in two phases: Wave 1 and Wave 2.

Wave 1 starting in 2013 only brings the features of 802.11ac supposedly less risky. For example, expanding the frequency from 40 MHz to 80 MHz and supporting 256 QAM modulation is quite simple, the manufacturer can issue a new prototype with these features and label the AC on it without even being able to. meets the standards.

Wave 2 starts in 2015 and brings with it the more difficult features of 802.11ac, the most important being MU-MIMO. If your AC router has before 2015, it does not have MU-MIMO.

What is MU-MIMO and why do you need it?

If SU-MIMO is a dealer, MU-MIMO is a divider with four pairs of hands, each of which will work with one player. MU-MIMO allows the router to split up individual packets and deliver to multiple devices at the same time.

Imagine you are watching Netflix on your computer, and your lover is using Skype on your phone. With SU-MIMO, the video may be jerky or degraded as the router often has to switch back and forth between the two devices to send data. But with MU-MIMO, it sends data continuously to both people.

Wi-Fi routers using MU-MIMO technology will be increasingly popular

Remember MU-MIMO does not speed up. It just keeps you out of the loop when connecting multiple devices, making the router not overworked. Instead of paying attention to each one, it will serve you all the time.

This is also a limitation because the router uses MU-MIMO technology only 2×2, 3×3 and 4×4 versions, meaning that it can only serve data streams between 2, 3 and 4 devices. If your router supports MU-MIMO 4×4, when using 6 devices, the router will have to divide the data stream and convert it to SU-MIMO.

Another minus point is that MU-MIMO signals work only on devices that can decode the 802.11ac protocol. This will not be worrying in the next few years. 802.11ac is becoming more popular but remember that older devices will not take advantage of this technology.