T-Mobile 5G Internet Gateway (Cisco MG51E) External Antenna Guide
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- The Best External Antennas for your T-Mobile 5G Internet Gateway
- Why External Antennas Are Critical for Improving Data Rates
- Installing External Antennas to your T-Mobile 5G Internet Gateway
- Step-by-Step Guide to Installing Adapters for External Antennas
- Positioning and Aiming MIMO Antennas
- T-Mobile 5G Internet Gateway Technical Specifications
- Supported T-Mobile Bands
- Cellular Modem
- Other
- Other Helpful Resources
- T-Mobile & Cisco Support Documentation
Looking to get the best possible data rates from your T-Mobile 5G Internet Gateway (Cisco MG51E) for T-Mobile Business Internet?
You’ll want to purchase four RP-SMA-Male to SMA-Female Adapters to connect external MIMO cellular antennas to the device’s four female RP-SMA ports.
In this guide, we'll:
- Recommend the best external antennas to use.
- Show where the RP-SMA ports are located.
- Explain how to aim the antennas for best results.
Note: The Cisco MG51E and Cisco MG51 have identical internal hardware, but the Cisco MG51 lacks the ability to use external cellular antennas. If you have the Cisco MG51, check out our guide for that device here.
The Best External Antennas for your T-Mobile 5G Internet Gateway
Using a MIMO antenna outside your building, pointed at the nearest tower, can help you get the fastest LTE data rates possible.
The T-Mobile 5G Internet Gateway (Cisco MG51E) has four cellular RP-SMA ports on the back. These allow for a 4x4 MIMO antenna array to be connected to the device.
Which of the two different 4x4 MIMO External Antenna Kit options to use depends primarily on how much time you're willing to spend on aiming.
The easiest antenna choice for the T-Mobile 5G Internet Gateway is our QuadMini Antenna Kit. With up to 5.2 dBi of omnidirectional gain and multiple mounting options, it is designed to be extremely simple to install outdoors or indoors, at home or in an RV.
QuadMini: Low-Profile Omni 4x4 MIMO Antenna
Upgrade your 5G in minutes with no aiming, and four easy mounting options.
However, if you're willing to spend a little bit of time aiming, our QuadPro Antenna Kit will generally get you the fastest data speeds, thanks to its 9.1 dBi of directional gain. This is particularly important if you're on the edge of coverage, or have very weak signal.
QuadPro: High-Gain Directional 4x4 MIMO Antenna
Aim QuadPro at your nearest tower for blazing data, even at the edges of cellular coverage.
Why External Antennas Are Critical for Improving Data Rates
Most people think that external antennas primarily help you increase your data rates by increasing the signal strength. But that's not the case.
An increase in signal strength is often less important than other ways that external antennas help.
Here are the three main ways that external antennas help you increase your data rates:
-
They Improve Signal Quality
In 4G LTE and 5G networks, signal quality is measured as SINR (Signal to Interference plus Noise Ratio) or sometimes as RSRQ (Reference Signal Received Quality).
Improving signal quality has a huge impact on your data rates.
Higher data rates allow your hotspot to communicate using "higher order modulation schemes." That means they can use the same wireless spectrum to send more data per second.
However, there's one big caveat:
In order to improve your signal quality, you need to both aim and shield your outdoor antenna properly. We talk more about this in the next section.
-
They Allow You To Connect On More Bands
Routers like this T-Mobile Gateway support an LTE feature called "carrier aggregation."
Carrier aggregation allows the T-Mobile Gateway to connect on multiple cellular bands simultaneously.
The more bands you're connected to, the greater the bandwidth, and the higher your data rates.
However, many of the higher frequency bands aren't able to penetrate into buildings. Using external antennas allows you to access higher frequency bands, which are often less congested and offer higher speeds than lower frequency bands.
-
MIMO Isolation
MIMO (Multiple Input Multiple Output) technology uses signals traveling along multiple paths simultaneously, increasing both bandwidth and reliability in wireless connections.
MIMO isolation is the antenna's ability to handle several data streams at once, cleanly and without interference, leading to quicker data speeds and steadier connections
Our external antennas are specifically designed for superior MIMO isolation, and dramatically outperform standard built-in antennas found in most home devices.
This means you'll see a more reliable connection with enhanced bandwidth, ensuring smoother streaming, gaming, and browsing with minimal interruptions.
Installing External Antennas to your T-Mobile 5G Internet Gateway
Before getting started, it's always a good idea to run a couple of speed tests indoors from a device connected to your T-Mobile Gateway's LAN port. The results will fluctuate a little, but this is the baseline you're trying to improve.
Once you've tested your baseline internet speeds, you're ready to install external antennas.
In the next section of this guide, we'll show you how to connect adapters for external antennas to your T-Mobile Gateway.
The T-Mobile 5G Internet Gateway (Cisco MG51E) has four cellular antenna ports, each pair of ports is located on the top and bottom of the device. These ports, labeled A through D in the image below, are the ports your MIMO external antenna(s) will be connecting to.
Note: The T-Mobile 5G Internet Gateway (Cisco MG51E) does not officially support third-party cellular antennas.
The cellular antenna ports were designed with RP-SMA-Female ports, rather than the industry standard SMA-Female ports, for Cisco's official MG smart dipole and smart patch antennas.
Step-by-Step Guide to Installing Adapters for External Antennas
Before you get started, you will need four RP-SMA-Male to SMA-Female Adapters to enable the attachment of external MIMO cellular antennas.
Step 1: Disconnect all of the paddle antennas from your T-Mobile Gateway.
Step 2: Connect the RP-SMA-Male to SMA-Female adapters to the newly available cellular RP-SMA ports on your T-Mobile Gateway.
Step 3: Connect the external MIMO antennas to the RP-SMA-Male to SMA-Female adapters on your T-Mobile Gateway in the order shown below:
Note: For our 4x4 MIMO Antenna Kit, the cable paths of the Quad-RS240 cable are labeled 1 through 4 on the cable jackets to assist with matching the cable connectors on each end of the cable.
Congrats! Your T-Mobile 5G Internet Gateway (Cisco MG51E) is now connected to your more powerful MIMO External Antennas.
Positioning and Aiming MIMO Antennas
Correctly positioning and aiming MIMO antennas is crucial to getting the best performance to your T-Mobile Gateway, or indeed any other router.
We've actually compiled a detailed QuadPro and QuadMini instruction manual to accompany our own MIMO Antenna Kits, where we go into depth on the best ways to aim the antennas.
The goal is to find the best location and direction for the antenna(s) to maximize data rates to the hotspot. It can take a little patience, but can have a huge impact – it’s worth a bit of extra effort!
Once you've got your external MIMO antennas connected, you're ready to go outside with your "test-rig".
With each location and direction you try, run a couple speed tests, and make a note of the results. Here are all the locations and directions where we recommend testing your MIMO antenna:
Pro tip: Don’t just go to the highest point of the roof! While signal is generally stronger the higher you go, there’s also often more interference. We’ve found it’s often better to mount the antenna(s) on the side of the building where the structure can shield the antennas from interference.
Once you've found the position which gets you the highest data rates to the T-Mobile 5G Internet Gateway, that's where you'll want to install the MIMO antenna. Go ahead and mount the antenna, run cables inside, connect everything up, and enjoy superior data rates!
T-Mobile 5G Internet Gateway Technical Specifications
Supported T-Mobile Bands
- 4G LTE: B2, B4, B5, B12, B46, B66, B71
- 5G NSA: n41, n71
Cellular Modem
- MIMO Support: 4x4 MIMO
- Carrier Aggregation: Up to 7x Downlink, Up to 2x Uplink.
- LTE Performance Category: Cat 20
- Max Theoretical Speeds:
- Passthrough Mode: 2.0 Gbps Download, 300 Mbps Upload
- NAT Mode: 1.5 Gbps Download, 300 Mbps Upload
Other
- POE+ Ethernet Ports: 1x 2.5 Gbps LAN RJ45 port, 1x 2.5 Gbps WAN/LAN RJ45 port
- SIM Slots: 2x 4FF “Nano” SIMs
- IP Rating: IP67
- Power: PoE+ or DC Power Adapter
Other Helpful Resources
T-Mobile & Cisco Support Documentation
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