LTE antenna choices – some considerations
In this article we will try to help you make the correct LTE antenna choices whilst keeping the terminology as simple as possible and try minimise the use of technical language and acronyms.
What is 4G or LTE?
In brief, although technically different, the terms 4G and LTE are used interchangeably by many to describe licenced cellular network services that offer both voice and high speed data. Worldwide, local operators have a licence from a national government to run a wireless network based on 4G and LTE technology and offer access to this network to users. For the purposes of this article, we will refer to these services as LTE services from now on.
Why would you use a LTE antenna?
The reason to use a LTE antenna is that without an antenna a LTE enabled device will not connect to a network. Many devices such as mobile phones already have LTE antennas integrated and do not require an external antenna. However many routers, modems, access points and LTE enabled systems simply have one or two LTE antenna connectors on the device and rely on the user or installer to select the correct antenna. In some cases, the antenna(s) supplied with the router or device are inadequate for the application so a better and higher performance antenna is required.
Can I just use any old antenna?
We don’t want to start drawing tenuous analogies, but in simple terms the quality of the antenna is as crucial to the success of a LTE wireless system as quality tyres are critical to the road handling of a car. Ergo if the true specification of the LTE antenna is sub-standard, then this will severely impact wireless performance and reduce download speeds. Using the correct type of antenna from a reliable manufacturer is an effective way to help preserve wireless performance.
My router, modem or device has two LTE connectors. What do I need?
With LTE services, many new routers and access devices have two LTE antenna connectors on the back. By using two antenna ports simultaneously, the download speeds to the user can be increased. In very simple terms, this is using two antennas at the same time, a technology called MIMO (multiple in multiple out). The LTE antenna choices for MIMO are either use one separate antenna for each port or use a MIMO antenna which has two antenna ports. Using a MIMO antenna means that the installer does not have to install two antennas, one MIMO antenna with two antennas ports does the job. If your router or device has two antenna ports available, then it is recommended that you use (connect up) both ports with an antenna to maximise wireless performance.
If your modem, router or device has one single LTE antenna connector, then connecting a single port LTE antenna is the way to go. Then the best idea is to purchase a LTE with a single antenna connector such as the HGO-4G-LTE or the SMP-4G-LTE antenna.
Do I need an omni-directional or a directional antenna?
Firstly, let’s clarify the difference between an omni-directional and directional antenna. An omni antenna radiates in every direction (imagine a ceiling mounted light bulb in your lounge for example). A directional antenna radiates in one direction (imagine a beam from a torch that illuminates in one direction only). The omni antenna can pick up signals from LTE masts in every direction. The directional antenna, however, has to be pointed at a LTE mast to be able to pick up a signal (think of the traditional TV antenna on your roof). Typically, directional antennas offer higher performance as typically they have higher gain, but they need to be installed correctly, i.e. pointing at the local mast, otherwise they will not work. Omni antennas typically have lower gain, but installation is very easy and often they can “see” more than one local LTE mast so thereby offer some redundancy if one LTE mast is offline.
If you are on the very edge of the network coverage and you absolutely know where your local LTE mast is, then a directional LTE antenna could be a good choice for you. Otherwise it is probably worth going with an omni antenna for ease of installation and due to the fact that it could see more than one local mast.
An example from our portfolio of a LTE MIMO omni antenna is the LMO7270 antenna.
It can be purchased online via the Connex webshop.
An example from our portfolio of a LTE MIMO directional antenna is the SMP-4G-MIMO antenna which can be purchased from the Connex webshop.
Does my antenna have the correct frequency for my LTE installation?
LTE frequencies do vary from country to country. In most countries in Europe LTE operates between 790-2690 MHz and many LTE antennas support these bands. Our advertised LTE antennas all support these frequencies. Some countries in Europe also offer 450 MHz LTE – there are some specific antennas that address the 450 MHz band such as the VLP4, the LMO4547 or the UWB45727 antenna, but most LTE antennas do not support 450 MHz. For North America you will also need the 690-790 MHz band, many antennas support these frequencies, but you will need to check the formal specification to be sure.
For our industrial installation, we need a covert or low profile antenna. What do we need to know?
For low profile installations, there are a number of LTE antenna choices in the market. Most however, due to the nature of low profile technology, need to mounted onto a metal surface (known as a groundplane) to radiate effectively. Low profile LTE antennas can be magnetic, tape or through-hole mount. Solutions such as the SmartDisc or AllDisc antennas are through mount and typically require a groundplane whilst magnetic mount antennas (check out the LTE-HIGAIN-MAG) by definition a designed to mount onto a metal surface. There are antennas available that can mount on non-metal surfaces, but they are typically not as low profile as the others. Please contact us if you feel you need specific advice on this.
I have seen a LTE antenna with 35 dBi gain. Is this the best choice?
There are a number of suppliers at the low end of the market who are advertising antenna products with spurious specification claims. Even with a big multi element directional antenna (in the style of a traditional TV antenna) called a Yagi, it would be unusual to see gain figures for LTE at more than 12 dBi and many users do not want a huge yagi antenna in their installation. If you stick with reputable manufacturers who warrant their specifications then you know what you are getting. For an external omni antenna if the gain is somewhere between 3 and 6 dBi then this is realistic. For a directional panel type antenna if the gain is between 5 and 10 dBi this is also realistic. Unfortunately there are sensationalist claims about antenna performance in the market so it makes sense to stick with known antenna brands. Our suppliers such as Sirio, Laird, EAD, PCTEL, Smarteq and SCAN are reputable brands you can rely on.
What RF cables do I need?
Some external LTE antennas are bundled with coaxial cable as standard. In some ways this can make life simple, however in many cases the standard cable length might not be appropriate for the installation. For example, an antenna might be bundled with 5M integrated cable when the installation requires 15M. The choice of cable should really depend on the length needed. For up to 10M BWL195 cable may be more than adequate. Beyond that to 15M, a thicker 6mm diameter cable such as RF240 is required. For 20 or 25M, a 10mm diameter cable such as RF400 would be more appropriate. For any cable length above 5M for your installation, if you unsure please contact us for advise and we’ll recommend the correct cable for you. We can pre-terminate these with the correct connectors to save you from purchasing crimp tools and saving you time.
I need a LTE terminal antenna for my device. What do you suggest?
Firstly, you have to determine what LTE antenna connector is on your device. Often it is a connector called SMA and is the female version. If you are not sure, check out this blog post that has a connector guide on the 10 most common RF connectors for wireless. Apart from the connector, you will need to know the orientation for the antenna. Does it need to be exiting vertical from the device or horizontally. Useful in this instance is a multi-position antenna such as the WTR7270 antenna which can lock in the horizontal or vertical position depending on the application.
My LTE antenna choices are quite wide. What should I focus on?
To select your antenna, you need to consider the signal strength at the location of installation. If the signal strength is OK, then probably an omni antenna will be OK, if it is weak then maybe a directional antenna might be more suited. Also consider where you will have “line of sight” to the mast, high up on a roof or a pole will often give you best chance of the antenna “seeing the mast”. Try to avoid installing the antenna where it has to radiate through a thick wall, insulated roof or if there is another building or wall very close by!!
You will also need to think about how you will mount the antenna – wall, pole, surface-mount (and whether your desired antenna supports that mounting method), the shortest cable run available to you to avoid signal losses across the coaxial cable. Also focus on an antenna solution from a reputable manufacturer so you can rely on build quality and performance.
Thank you for taking the time to read some our considerations regarding your LTE antenna choices. We hope they will assist you selecting the correct antenna. If you require further assistance, please feel free to contact us.
Tags: 4G, antenna, best, choice, coaxial, directional, gain, installation, LTE, omni, SMA