4G reception in your area sucks? Let’s setup an external 4G antenna.

Greshan Bovithanthrige
6 min readSep 23, 2022

--

The idea behind setting up an external 4G antenna is to establish a clear line of sight between the base station tower (The cell tower which you get the signal from to your house) and your 4G router. Raising the external antenna as shown in the picture above lets you avoid any obstruction in between your router and the base station tower. (Source: Internet)
This is how a base station tower usually looks like. A raised 4G antenna like in the picture above will maintain a line of sight connection with this tower.

Can this be done with any broadband 4G router?

Short answer?

Unless it’s a portable battery powered router. YES (Even with some battery powered routers, this is possible. Antenna connector types may vary. Refer to the manufacturer's documentation)

There are two ways in which you can achieve this

1. Getting an OEM router which supports an external antenna like I did.

2. You can get an after market YAGI or Omni directional antenna for the router you already have. (Antenna type will depend on the location you are in.)

OEM routers which support external antennas. (This particular antenna is a directional antenna)

4G CPE ZLT P11 Router with the external antenna (looks like a vertically setup Omni directional antenna. But it’s not), this is also a form of directional antennas.)

Getting a YAGI or an Omni directional antenna for the router you already have.

What is a YAGI Antenna?

4G external antenna. YAGI antenna
YAGI Antenna (This is the traditional look of a YAGI “Directional” antenna, however there are modern antennas which have different shapes. Irrespective of the shape and design, they all fall under the YAGI “Directional” antenna category. The antenna my router has, is a great example for that.)

YAGI antenna also known as Yagi -Uda (Directional/ Uni — Directional) antennas, are used for communications between medium distances. And this antenna type is known as directional antennas because of their ability to pull signals from a direction, which makes them stronger than Omni directional antennas because they’re directed at one direction. YAGI antennas can communicate with much greater distances as long as they pointed correctly at the signal source. This is essential for optimal reception.

When you buy an after market antenna, please make sure to confirm the type of the antenna with the manufacturer. That is, if you’re not sure from the look of it.( Refer to the technical documentation or you will have to raise a ticket with the manufacturer.)

What is an Omni Directional Antenna?

4G external antenna. Omni directional
Omni Directional antenna with a Radome housing (Image source: Internet).

As the name suggests, these antenna’s pull signal from all directions (360 degree antenna pattern), unlike Yagi antennas. The trade off with Omni directional antennas is that, they pull signals from all directions by reducing their ability to pull signals from one direction. This reduces it’s effectiveness when it communicates with another antenna cause it’s not directional. Omni directional antennas are easy to spot because they’re usually fixed vertically and covered with a material that is transparent to radio waves. This housing is called a “Radome”. (See the above picture.)

When you buy an after market antenna, please make sure to confirm the type of the antenna with the manufacturer. That is, if you’re not sure from the look of it.( Refer to the technical documentation or you will have to raise a ticket with the manufacturer.)

Which type of antenna do you need?

If you’re trying to connect to the base station antenna of your Internet service provider (ISP), what you need is a directional antenna. You’re only looking to communicate with the base — station tower, so your objective is to achieve the optimal reception which can be done with a directional antenna.

However, if you’re in a location with multiple base station towers nearby, you can choose an Omni directional antenna for your project. Because that antenna will pick up reception from every direction it is able to.

How to configure the antenna you just bought for your router?

This will depend on the type of after market antenna you’re buying and the router you have at home. Generally, routers get 2 antennas or two antenna mounting points (Two female SMA connectors). So it will look something like this. (Refer to your router manufacturer’s documentation)

4G router
You will use these antenna mounting points for your external antenna setup. You can either use one or both depending on the after market antenna you got. In this case, the cable you use will be a coaxial cable with a SMA male connector. (See the picture below)
This picture denotes the cable (Premium 240 Series Low-Loss Coax Cable) and the connector you use (Sub-Miniature Version A, Male and Female) to connect the antenna to the router.

NOTE: Try and limit the length of the cable run as the longer you run cables, the more you lose the reception gained from the antenna you setup. Which as you can see, defeats the whole purpose of setting up an antenna in the first place.

Experiment with the antenna by keeping the router close to you. Raise it, lower it, change it’s location and change directions. That way you will be able to see which direction and height are optimal for best results.

Connect to to your router via Wi-Fi from your mobile phone. Then, log into the management webpage too see the signal strength change in real time. Alternatively, you can check, the on screen indicator of the router for signal strength change in real time.

4G router with YAGI antenna
A YAGI antenna like this will only have one cable going to the antenna from the router.
MIMO antenna 4G
A MIMO (multiple input, multiple output) antenna like this will have two wires going to the antenna from the router. MIMO is an antenna technology for wireless communications in which multiple antennas are used at both the source (transmitter) and the destination (receiver). Even though this particular antenna is an Omni Directional antenna, inside this, it contains two different antennas.
Huawei B310 4G router, antenna configuration page
In both of the cases, either you use one antenna port or two, you will have to go into your router’s management page to set it up. Please refer to your router manufacturer’s website/ manual for this process. This screenshot is from a Huawei router configuration page.

My external 4G antenna setup

For my external antenna setup, I used a TOZED KANGWEI ZLT P11 router which relies on a directional antenna. This antenna is PoE. So it is powered by the router with an exterior-grade ethernet cable which is weatherproof.

Raised 4G antenna
Antenna raised to reach a line of sight with the base station tower which is 5–6 miles away.
Directional 4G antenna
Close up of the external directional antenna. (Pointed at the general direction of the base — station tower)

I have NOT grounded this antenna as of now, simply because it is not the raining season here. However I plan on grounding it soon.

If you plan on raising an antenna like this, I strongly advise you to ground your antenna to minimize the chances of injuries to yourself or damages to your electrical equipment in the case of a lightning strike.

And I advise you further: When you use a router with an external antenna, to the best of your ability, connect to it via Wi Fi. This will limit the damage to an extent in the case of a lightning strike.

This is how an antenna should be grounded to minimize the potential damage from lightening.

How to ground a 4G antenna DIY
Alternatively, you can ground the antenna using a dedicated grounding electrode or alternatively you can use the grounding electrode that is used for your house as well.

The antenna pole I chose for my project

Pole for a 4G antenna
I had to weld two left over poles together to achieve this length. Note that, after the welding job is done, the pole has been painted over with anti corrosive paint.

Please make sure to plan ahead when working on something like this, because the grounding mechanism is a must for these antennas.

And please paint the pole with some kind of a anti corrosive paint. So you can protect it from getting corrosive over time.

This mounting mechanism doesn't include grounding. I will update this post as I ground my antenna over time.

Conclusion

Having low cell reception sucks. Specially when you're working from home. My connection stability was okay, but I wanted to make sure that I am getting a good reception, so I decided to take on this project. And it yielded great results. Before setting up the external antenna, I had 25% of cell reception, which was more than enough for my work. (As you can see at the end, after the project is completed, I was able to reach 99% signal strength)

You can get the signal strength from either on screen display of the router, or if it doesn’t have one you can log into the router page using it’s IP. (Check the back of your router for a sticker. It will contain everything you need, username, password and IP etc.)

Router login credentials
If you check the back of your home router you can see a sticker like this containing all the info you need.

I know you’re waiting to see the result of our project. Here you go.

4G external antenna signal streangth

PS: Some images here are taken from various eCommerce websites. Other photographs and screenshots are taken by me.

--

--