Wi-Fi Backhaul on a 160 MHz Channel – The Gbps in Sight!

In the past, I’ve come very close to the 1 Gbps of a standard Ethernet connection over my Wi-Fi backhaul between a Fritzbox 7590 and a FritzRepeater 3000. However, it was not quite 1 Gbps, and every now and then the speed dropped to 500-600 Mbps. This was mainly for two reasons: While both devices supported 160 GHz channels between them on paper, AVM seemed to have had a problem with it on their Repeater 3000 and hence, they limited the channel bandwidth to 80 MHz in some software versions. Luckily, 4 MIMO streams are supported over 80 MHz, so I could still almost reach the 1 Gbps, despite the limited bandwidth. The second reason why I was a bit unhappy was that some software versions often fell back to the lower part of the 5 GHz band with a much more limited transmission power. So that was the status quo for quite a while.

While both products are now well into their 5th year on the market, AVM still keeps improving them. After a recent software update, I noticed that both problems seem to have been fixed and I’m one step closer to that magic 1 Gbps barrier. The picture above shows the channel assignment on the FritzRepeater 3000. The greenish yellow bar indicates a channel bandwidth of 160 MHz being used as backhaul to the Fritzbox 7590, which acts as my VDSL router and Ethernet switch for my home servers. In this configuration, only 2×2 MIMO is supported, but 2×2 MIMO on 160 MHz is still better in my setup than 4X4 MIMO on 80 MHz. Not much, admittedly, but still 50-60 Mbps faster. So instead of the 830 Mbps I previously got when the backhaul used 80 MHz on the higher 5 GHz channels, I now get around 880 Mbps over the 160 MHz channel. Compared to an Ethernet link on which iperf3 shows me 934 Mbps, that’s just 50 Mbps less. OK, Ethernet is bidirectional, Wi-Fi is not. In practice, however, I only either upload or download data to my servers at any one time, but never do both simultaneously.

Very well done AVM, thank you very much for supporting your products for such a long time! Next stop: The next generation Fritzbox is said to support 802.11ax, the 6 GHz band and at least one 2.5 Gbps Ethernet port. Let’s see if that comes with 320 MHz bandwidth support and 5 + 6 GHz channel bundling. If so, I can’t wait to give this a try and upgrade to 2.5 Gbps on some endpoints as well.