How to pick the right router for 3G/4G broadband

People regularly ask me what router or antenna to get for mobile broadband.  Most people who ask are in rural areas that are stuck on a slow DSL or fixed wireless connection.  Before even considering a router or antenna, I recommend first finding out which networks are available in the area.  Then check whether 3G or 4G is available on each network.

This article will mainly focus on routers, see my other article for antenna advice.  I recommend that one first sees how they get on with a suitable router as an antenna may not be necessary. 

Most mains operated desktop routers have sensitive internal antennas, generally eliminating the need for an indoor antenna.  In fact, some indoor antennas perform worse than the built-in antennas of a decent router.

Article content

• Finding the right network – Don’t blindly sign a contract!
  • Performing test runs – 4G might not be better.
• Choosing the right router – Do you really need a flagship router?
  • 3G and 4G band support. – Before buying overseas or used.
  • Huawei B535 – 4G+ capable and ideal first router.
  • Huawei B818 – Ideal for newer masts or built up areas.
  • MikroTik Chateau LTE12 – Powerful feature packed router.
  • Huawei B593s-22 or B315 – Low cost used options.
  • Huawei E5186 or B525 – Used 4G+ capable options.
  • TP-Link Archer MR3420 – Convert your 4G USB modem.
  • Outdoor router – Boost fringe 4G reception.
  • Cell tower range limit note – No antenna can overcome this!
• Routers to avoid – Don’t get stung with weak sensitivity, poor Wi-Fi coverage or a long contract.
  • Portable hotspots / MiFi – Sacrifices made for portability.
  • 3G modems – No diversity kills performance.
  • Network branded routers – Long contracts + they’re locked!
• Mobile phone as a router / MiFi – Limitations of using a phone hotspot to provide broadband.

Finding the right network

If undecided on a network, first check out my earlier guide.  It covers the largest 4G packages each network and virtual operator provides in Ireland.  All three major networks offer a prepay mobile broadband option, so I recommend getting a prepay voice SIM with each. It’s a small price to pay to avoid the hassle of signing up to a broadband contract just to test the network, only to have to cancel it if it doesn’t work out. 

Three, Eir and Vodafone prepay phone SIMs will also work for testing in a router and offer much greater data allowances.  The speed may differ from a broadband SIM, depending on traffic prioritisation.  For Vodafone prepay, the APN must be set to ‘live.vodafone.com’ to use a phone data plan with a router, otherwise it incurs out of bundle charges. 

Performing test runs

Get a spare 4G (or 5G) capable phone to try each SIM with and configure it with the correct APN.  Most SIM cards break apart into micro and nano size.  These snap together again to get the full mini SIM size that fits most routers.  Check around the building for the strongest 4G reception.  The apps network Network Cell Info Lite and Network Signal Info (right image) shows a live decibel reading of the signal, ideal for finding the sweet spot.  Run some speed tests early in the day, before noon.  Repeat again between 8pm to 10pm (peak time) with the phone, preferably held outside an upstairs window.

If the phone remains in 3G mode, toggle the airplane mode on/off while holding it outside an upstairs window.  For HTC phones, toggle to WCDMA only and back to GSM/WCDMA/LTE Auto to lure it to 4G mode.  With an Android phone, see this guide to see if you can force the phone into LTE-only (4G) mode.  With Samsung phones, there is a Samsung Band Selection App to select LTE only.  If 4G reception is still not possible even outside the window, then it is unlikely a 4G router or an external antenna will provide 4G on the network.  For 3G speed testing, first aim for the highest signal reading possible in the Network Signal Info app.

With a full signal reading, the speed tests on the phone generally corresponds to what a dedicated router will achieve.  If the bar reading is half way or higher, a desktop router will likely get a full or near full signal reading in the same spot without any external antenna.

The peak time speed tests will give an idea of what to expect in the evening with a dedicated router.  If the performance severely deteriorates during peak time, try a speed test in 3G mode.  4G coverage areas with high contention often have lighter 3G network load.

Choosing the right router

As mobile broadband is portable, there are a wide range of dongles, portable hotspots, wingles and routers to choose from.  I strongly recommend going for a mains operated desktop router.  Its internal antennas are far more sensitive than the tiny internal antennas in dongles and portable hotspots.  They also deliver greater Wi-Fi coverage, much like a DSL router. Huawei and MikroTik routers have Android Apps available for viewing live signal readings.  This is especially useful when trying to position a router or its antenna.

3G, 4G and 5G band support

Before purchasing a second hand router or from an international seller, check the list of bands the router supports.  For example, many routers supplied on the US market lack most or all the Irish 3G/4G bands.

3G bands in Ireland

• 900MHz – Widespread use in rural areas due to its long propagation.
• 2100MHz – Primarily urban use.  Some older rural 3G masts put up before 2015 continue to use 2100MHz.

4G bands in Ireland

• 800MHz (LTE FDD band 20) – Widespread coverage due to its long propagation.
• 1800MHz (LTE FDD band 3) – Primarily serves urban areas due to its shorter propagation.  This band provides wider channel bandwidth.

Temporary 4G bands in Ireland

To provide additional network capacity during the pandemic, ComReg issued temporary spectrum rights on the 700MHz and 2100MHz bands to all three major network operators.  This temporary spectrum will expire on the 1st October 2021. 

• 700MHz (LTE FDD band 28) – Widespread coverage due to its long propagation like the 800MHz band.
• 2100MHz (LTE FDD band 1) – Primarily urban areas where the networks were operating 3G on the 2100MHz band.  The temporary spectrum rights allows the network operators to temporarily reprovision this 3G band for 4G.

5G bands in Ireland

• 3.6GHz (NR TDD band n78) – Primarily serves urban areas due to its very short propagation and poor penetration of building materials.  10km physical range limit due to TDD synchronisation between the uplink and downlink time slots.  Massive bandwidth of between 80 and 105MHz. 
• 1800MHz (NR FDD band n3) – Three and Eir are currently refarming some of their 4G band 3 cells for 5G.  This band provides better penetration through building materials than the n78 band, but with only a slight speed improvement over 4G due to the narrow 15MHz of bandwidth.

4G+ coverage areas serve at least two LTE bands, e.g. bands 3 + 20 for networks in Ireland.  When an LTE 6+ capable router connects in ‘4G+’ mode, it actually connects to multiple bands simultaneously.  This is known as carrier aggregation.  Higher end routers may connect three carriers, such as bands 1 + 3 + 20 in an area where band 1 is reprovisioned for 4G use. 

The 2600MHz band (LTE FDD band 7) is not currently in use in Ireland.  See this Wikipedia article to see what LTE bands each EU country uses.

If in doubt on a particular router, leave a comment below mentioning the full model #.

Huawei B535

For those in a rural area or on a limited budget, router supports all the 4G bands currently use in Ireland.   It is an updated model of the B525, adding support for 4G band 28.  Like the B525, it is capable of aggregating two bands for 4G+, useful during peak time where the bandwidth can vary between the bands.  

The B535 has a similar size and footprint to a DSL router.  It is available new for around £120 on Amazon, sometimes on sale for around £100.  Three provide this router with their broadband contracts.  This router provides 802.11ac Wi-Fi capability, Gigabit Ethernet ports and two SMA connectors for attaching both leads of a MIMO 4G antenna.  These are less common second hand and in turn gives them an excellent resale value. 

Unlike the Huawei B525, this router does not have any telephone jack. 

Huawei B818

For those in or near larger built up areas, the B818 is capable of aggregating 3 carriers.  It also supports 4×4 MIMO (4 internal antennae) and 256QAM (higher encoding efficiency), potentially delivering faster throughput where the mast had recent upgrades.  Where three or more 4G bands are in use, this router is capable of aggregating 3 carriers, e.g. bands 1+3+20 or 1+3+28.   

For connectivity, it has two Gigabit Ethernet ports, 802.11ac Wi-Fi capable and two TS9 antenna connectors.  It also has a telephone jack, capable of voice calls with a phone SIM (reported to work with Three, but not GoMo.)  To use an antenna with SMA connectors, this router requires a pair of TS9 to SMA adapters to attach both leads. 

MikroTik Chateau LTE12

For network technicians and enthusiasts looking for a more advanced router, this router runs MikroTik’s powerful RouterOS software.  It features 5 Gigabit Ethernet ports, two SMA connectors for external 4G antenane and a USB port.  Like other MikroTik routers, the ports are individually configurable with VLAN support, VPN client and server capability, a command line terminal and LTE pass-through.

It is capable of 3 carrier aggregation, including band 28.  In addition to LTE band locking, this router is also capable of cell ID locking.  This is very useful for locking the router to a specific cell, particularly in an area where the user picks up multiple masts with different levels of congestion, especially on the uplink.  It can also provide a list of neighbouring cells, useful for picking out cells to try locking to.  See this post as an example. 

Huawei B593s-22 or B315

For those on a limited budget, I recommend starting off with either of these two routers, widely available second hand.  The B593s-22 is reported to have more sensitive internal antennas than the B315 and many other brand routers. For users that are far from the cell tower (e.g. 20+km), choose the B525 or B535 as it’s less likely to run into the 4G range limit issue. 

This router is similar in size to typical standing DSL router and provides 300Mbps 802.11n Wi-Fi, 4 Ethernet ports, 2 SMA antenna connectors and built-in VoIP support with two telephone ports.  Although the newer B311 looks similar, it has just one Ethernet port and one antenna port, which I recommend avoiding. 

Both routers are very stable and reportedly very reliable.  The B593s-22 costs around €60 to €80 used from European sellers.  The newer B315 was provided by Three, Meteor and Eir up until 2018.

Note: These two routers lack support for 4G band 28.  

Huawei E525 or E5186

For users living in or near larger towns, the B525 or E5186 are available second hand as a cheaper alternative to the B535.  If the network provider offers carrier aggregation (4G+) in the area, this can deliver improved performance by utilising bandwidth from bands 3 and 20 simultaneously.  This can be useful during peak time where congestion varies between the bands.  Note that neither of these support 4G band 28.

The B525 is available used for around 80 to 100 used from European sellers  Both Three and Eir previously provided this router with their broadband contracts.  The B525 is newer than the E5186 and provides 802.11ac Wi-Fi capability.  For those that just need the router short term, they maintain very good resale value. 

Huawei offers many higher end routers available both new and second hand such as the B618 and B715s-23c.  However, check the bands they support and that they have two antenna connections. 

TP-Link Archer MR3420

For users with an existing 4G USB dongle, this TP-Link router is a low-cost way of converting it into a standalone Wi-Fi network with Ehternet connectivity.  I know a few people who used this successfully for a few years.  As USB modems have a tiny internal antenna, I recommend getting an external antenna to improve the performance.

The TP-LINK Archer MR3420 typically retails for around £30, such as on Amazon.

Outdoor Router

For those living in a fringe 4G reception area, an outdoor router such as the MikroTik LHG LTE kit offers a combination of an outdoor router and directional antenna in a single unit.  This operates similar the outdoor ‘dish’ or antenna provided by most fixed wireless operators such as Imagine LTE.  By having the radio hardware and antenna in one unit, this eliminates signal losses from long coaxial cable runs and only needs a single cable.  Dish shaped antennae like the MikroTik LHG LTE work best on the higher frequency bands such as bands 1 and 3. 

This outdoor router receives its power over its Ethernet cable, supplied using an indoor 24v or 48v PoE injector.  The total cable run between the indoor Ethernet switch and the outdoor router can be up to 100 metres without affecting the performance.  For those that previously had a wireless Internet service provider (WISP), it may be possible to reuse the existing Ethernet cable and mast. 

Notes: Some outdoor routers do not provide 3G connectivity.  Make sure there is at least one bar of usable 4G coverage with the desired network with an LTE-only modem or router.  See the cell tower range limit note below.

The SIM card goes in the outdoor unit, so careful positioning may be necessary to keep it out of pedestrian reach.  Ideally, it should be high enough to require a ladder to reach.

Cell tower range limit note

Cell towers enforce a fixed distance limit based on the signal round trip time.  The maximum distance limit can vary between cell towers and even between bands.   Even a powerful antenna with clear line of sight of the cell tower cannot overcome this.

The distance limit appears to vary between LTE category 3 / 4 devices and LTE category 6+ devices, possibly due to better LTE timing advance precision on devices that support carrier aggregation, i.e. 4G+.  For example, with a high gain antenna, I can pick up Eir 4G (band 20) from a mast over 25km away with my B525 router, however, my B593s will refuse to connect to it despite showing the same signal reading.  A 4G signal on a mobile phone does not necessarily mean a usable 4G signal with a category 3 or 4 modem or router!

With 5G, the maximum range limit is approximately 10km with the 3.6GHz band n78.  Beyond this range, the progation time becomes too great for the modem and cell radio synchronise within the upload and download timeslots.  5G band n3 is likely to have a much grater range due to using FDD (Frequency Division Duplexing) like the 4G bands in use. 

Routers to avoid

3G modems and portable hotspots are considerably cheaper than dedicated desktop routers, but I recommend avoiding these as explained below.

Portable hotspots / MiFi

While these are tempting for their low cost and portability, avoid these for home broadband.  Based on my experience, the antenna sensitivity is often inferior to most mobile handsets and the Wi-Fi range is poor.  They have no network ports and the USB port will not work with most desktop routers, such as the TP-Link MR3420.  Running them continuously on mains power quickly deteriorates the internal battery.

One common mistake people do is try to use a portable hotspot with a WiFi extender/repeater.  The problem here is that these repeaters cut the bandwidth in half by repeating every bit of data across the wireless network.   Most portable hotspots do not offer Wi-Fi diversity, which further limits the Wi-Fi coverage and bandwidth.  Finally, I have yet to see a WiFi extender/repeater that does not intermittently drop out.

3G modems

All three major networks in Ireland provide diversity support on their 3G masts.  This can near double the bandwidth when used with a suitable modem or router that uses two antennas.  Unfortunately, very few 3G modems and hotspots support diversity.  Worse still, many older modems only support the slower WCDMA standards capable of 7.2Mbps or even less.  3G modems rated 21Mbps or lower or which have a single antenna input generally lack diversity support.

Most 4G modems and routers have two antenna inputs and support diversity with 3G masts.  This means that even if there is no 4G coverage in the area with any provider, a 4G modem or router is well worth considering.  I suggest going for a mains-operated desktop 4G router as this will provide better antenna sensitivity over USB modems.

Network branded routers

Three, Eir and Vodafone all sell a range of routers, hotspots and USB modems, which unfortunately are SIM locked.  Unlike phones, no network will unlock their data device, regardless of the device age or accumulated top-ups.  Most newer routers are even difficult, risky or expensive to unlock with software or a third party.

One exception would be on contract to reduce the upfront cost of the router.  Rural Wi-Fi does not appear to lock their router.

Mobile phone as a router / MiFi

For strong signal areas, a spare 4G phone can make a potential alternative to a portable hotspot or MiFi.  A 4G phone may also provide 4G connectivity to a Three mast, where the user is outside its distance limit for data devices.

Mobile phones do have several limitations. No antenna inputs, no network ports, limited Wi-Fi range, typical limit of 5 devices and slower to boot.  Some phones automatically switch off the hotspot mode after a set period or if there are no active devices.

Users with a dual SIM phone can potentially use the second SIM slot for the data SIM.  This can be very useful with Three’s prepay “All You Can Eat” or the large 80GB allowance on Eir/GoMo.  At home, this can help supplement an existing broadband connection or data limit.  On the move, the phone can use the second SIM as its data connection.  This can eliminate the need for a data plan on the primary SIM.

Note: For those considering getting a mobile repeater to boost their 4G signal, repeaters do not provide MIMO.  This means the maximum 4G speed may be half that of using a MIMO antenna with two coaxial leads to a 4G router on the same network.  The repeater will need to boost 800MHz for most rural 4G masts or dual band (800 + 1800MHz) to provide 4G+ in urban areas. 

Article last updated 16th March 2021.