Vodafone single or dual stream (2x2 MIMO) LTE?

cohr5xei

Hi.

I recently bought an external 2x2 MiMO antenna to boost my reception (which it does great).

It comes with two antenna cables but plugging both cables into my router gives no boost in data speed over using just one cable. I'm getting ~12 Mbs.

So I'm wondering if my antenna is ok, or my router, or maybe Vodafone just provides single stream LTE on my mast? Does anyone know how to find this out?

(Hope I'm asking the question right).

Thanks.

editorsean

Is your MIMO antenna two separate antennas or the one complete unit with cables coming from it?

If the antennas are separate or can be detached or rotated, one antenna needs to be positioned in horizontal polarity and the other in vertical polarity. For example, if the antenna looks like two miniature TV antennas, one antenna needs to be positioned such that its elements are horizontal and the other with its bars positioned vertical.

If they are at 45 degree angles, such as a possible import from Australia, that would also explain the issue. In this case, they need to be rotated such that one is in a vertical position and the other in horizontal position.

Another thing worth trying is swapping cables between the #1 and #2 inputs on the router.

cohr5xei

My antenna is this one from dipol.ie
LTE MIMO Antenna: ATK-LOG LTE (800-2170MHz, 5m cable, SMA plug)

It's a single yagi type antenna with both horizontal and vertical bars and two cables. It doesn't make any difference which way I connect the cables to the router as long as one cable is in the "main" connection.

editorsean

Sorry, I miss-wrote the last line above. I was meant to say to try one cable on the main (#1) connection. If the performance is similar regardless of which cable you use, then the antenna itself is fine. If however just one cable worked and the router either gave 'No Signal' or would not connect with the other, then it likely would indicate a bad connection with the other cable.

I came across this article (based on the Australian LTE implementation) which mentions MIMO is not used when the signal falls below a certain threshold where it's difficult to distinguish between the two data streams:

It is important to know MIMO is switched on and off by the modem. The decision whether to use MIMO is negotiated with the cell tower, whereby the quality of the received and transmitted signals are assessed (a metric known as CQI). When signal strength or quality is low it's difficult for the modem to distinguish between the two data streams, so when signal levels drop below a certain threshold level, MIMO is switched off and the modem operates with only one antenna (Port 1 on Sierra Wireless modems).

The following are a few other suggestions worth trying:

If the antenna is easy to access, try turning a few degrees each direction along with re-running the speed test until it reaches the peak speed. This may need to be done early in the day to avoid speed fluctuations from contention on the tower. However, I doubt contention is an issue with Vodafone, unlike the congested Three network.

If your router can manually choose between 3G and 4G, try a speed test in 3G mode in case the 3G reception is any stronger. On the Meteor network in Ballybofey, I typically get between 18Mbps and 24Mbps down, which I presume is due to it using MIMO on 3G here. The catch is the upload speed on 3G is limited to about 3.5Mbps.

cohr5xei

Plugging either cable into the "main" connection, leaving the "aux" disconnected, gives the same performance (~12Mbs). Plugging both cables in is also the same performance. Plugging either cable into the "aux" connection, leaving the "main" disconnected, doesn't work at all.

I'm about 5km from the mast but my router says I'm getting 4 of 4 bars of signal. I think I have the best position for the antenna but I can try again.

I can't manually choose between 3G and 4G but lately in the bad weather it has occasionally dropped back to 3G of it's own accord and I only got about 2.5 Mbs.

Thanks for the info and suggestions.

ED E

Most of the bands here are only 10Mhz, divided up and sold for a pretty penny by comreg. With the load on most masts as is I really doubt many operators will bother except in areas with lots of extra capactiy as you have 2x as many users per band.