MU-MIMO: What It Is and If You Need It - Explained
The Increasing Demand on Home Networks
The internet is rapidly becoming integral to daily life. Activities like streaming films, engaging in online gaming, and conducting video conferences with loved ones necessitate consistent connectivity.
However, the growing number of devices – laptops, desktop computers, streaming media players, and Smart TVs – requires substantial bandwidth.
This raises a critical question: will existing routers possess the capacity to meet the escalating demands of the future?
Introducing MU-MIMO Technology
MU-MIMO (Multi-User, Multiple Input, Multiple Output) technology emerges as a potential solution.
It’s a feature designed to enable routers to efficiently allocate bandwidth among connected devices.
Essentially, MU-MIMO aims to prevent network congestion by serving multiple devices simultaneously, rather than sequentially.
Is MU-MIMO a Worthwhile Investment?
The central question remains: does the current implementation of MU-MIMO justify its associated cost?
Furthermore, is your home network adequately equipped to fully utilize the benefits that this technology provides?
Determining whether MU-MIMO is a valuable upgrade requires careful consideration of your specific needs and existing infrastructure.
Factors to Consider
- The number of devices connected to your network.
- The types of activities performed online (streaming, gaming, etc.).
- The capabilities of your existing router and devices.
Bandwidth allocation is key to a smooth online experience.
Without sufficient capacity, performance can suffer, leading to buffering, lag, and disconnections.
Understanding MU-MIMO Technology
The term "MIMO" represents "Multiple-Input, Multiple-Output," describing how routers allocate bandwidth to connected devices. The majority of contemporary routers utilize "SU-MIMO," or "Single User, Multiple-Input, Multiple-Output" technology. With SU-MIMO, data transmission to devices occurs sequentially, one at a time.
Consequently, simultaneous data requests from multiple devices – such as streaming Netflix and YouTube – can result in one device receiving prioritized access while others experience a temporary delay until sufficient data is buffered. This prioritization isn’t usually noticeable to the user.
Although SU-MIMO routers handle multiple streams rapidly, creating the illusion of continuous data flow, there's still a sequential process involved. Consider a Pez dispenser attached to a rotating carousel as an analogy; each person will eventually receive candy, but the carousel must complete a full rotation before everyone is served.
"MU-MIMO" (Multiple User, Multiple-Input, Multiple-Output) routers differ by dividing bandwidth into distinct streams, providing simultaneous and equitable access for each connected device, regardless of the application being used. MU-MIMO routers are categorized as 2x2, 3x3, or 4x4, indicating the number of concurrent streams they can support.
This functionality is akin to a carousel capable of dispensing Pez candy in multiple directions simultaneously. Effectively, each device receives its own dedicated connection, with 4x4 MU-MIMO configurations supporting up to four simultaneous streams.
The primary advantage of MU-MIMO lies in its ability to maintain a consistent signal for multiple devices. Instead of intermittent interruptions caused by the sequential nature of SU-MIMO, MU-MIMO distributes bandwidth evenly, ensuring optimal speed for all connected devices concurrently.
Limitations of MU-MIMO Technology
While the benefits appear substantial, a significant limitation exists with MU-MIMO: effective operation necessitates complete compatibility between both the router and the connected devices.
Currently, MU-MIMO functionality is restricted to the 802.11ac wireless protocol. Many devices have not yet been upgraded to properly decode this signal. Furthermore, the number of devices equipped with MU-MIMO capability remains limited.
As of now, only a small selection of laptops feature MU-MIMO-ready wireless receivers. A similarly restricted number of smartphones and tablets include Wi-Fi chips capable of processing MU-MIMO streams, such as the Microsoft Lumia 950.
Consequently, investing in a router with MU-MIMO capabilities—typically an additional $50, depending on the model—may not yield immediate benefits. It will likely take several years before all devices within a home network can fully utilize this feature. Compatible MU-MIMO wireless USB dongles are available for desktops and laptops, but their higher cost compared to SU-MIMO receivers may deter some users.
Stream Limitations and Spatial Considerations
Another factor to consider is the maximum number of streams supported by MU-MIMO, currently capped at four. Adding a fifth device to the network will result in stream sharing, mirroring the behavior of a SU-MIMO router and diminishing the intended advantages.
Moreover, MU-MIMO broadcasts operate directionally, requiring devices to be spatially separated for optimal performance. For instance, if a movie is streamed to a television in the living room while a Nintendo 3DS is used on a nearby couch, both devices may be forced to share the same stream.
Due to the inherent mechanics of MU-MIMO streams, there is currently no solution to circumvent this limitation. Therefore, in smaller living spaces or when most network activity occurs within a single room, MU-MIMO may not offer any discernible improvement over SU-MIMO.
Related: Understanding Dual-Band and Tri-Band Routers
Is a MU-MIMO Router Right for You?
A MU-MIMO router can be beneficial if you have four or fewer devices capable of utilizing MU-MIMO, and these devices are positioned at considerable distances from each other within your home.
Consider a scenario where a dedicated gamer is utilizing a connection concurrently with someone streaming 4K content on Netflix in a separate room. In such instances, the advantages of MU-MIMO could prove valuable over time.
However, it’s crucial that both the streaming device and the laptop possess the capability to decode a MU-MIMO signal for this to be effective.
Further Reading: Enhancing Your Wi-Fi – Upgrading Your Wireless Router for Improved Speed and Reliability
If your internet service is DSL and your bandwidth is limited, a router – whether MU-MIMO enabled or not – won't increase the fundamental download or upload speeds provided by your Internet Service Provider.
MU-MIMO functions as a bandwidth optimization tool, operating within the constraints of your existing internet speed.
Currently, MU-MIMO is most advantageous for larger households with numerous devices requiring substantial individual bandwidth, particularly when used in different areas of the home.
The added expense of this newer technology may be a deterrent for typical consumers until more widespread usage patterns emerge and manufacturers reduce the cost.
Looking Ahead with MU-MIMO
Despite the limited number of devices currently supporting it, exploring MU-MIMO routers remains worthwhile.
These routers don't address immediate issues for most internet users, and widespread adoption of the MU-MIMO protocol in mainstream devices isn't anticipated before 2017.
However, for those who can leverage its capabilities, it represents a robust feature that could prepare your home network for future bandwidth demands.
For example, early adopters of devices like the Lumia 950 could benefit from this technology.
Image Sources: Netgear, TP-Link, Microsoft.