Four Stream Performance
NETGEAR supplied two R7500v2s so 4x4 throughput could be tested. The pair were set up in open air, approximately eight feet apart, one as a normal router and the other in wireless bridge mode. The in-house 5 GHz network was idle and only beaconing (no traffic). Channel was set to 153, bandwidth mode was in its default 80 MHz mode and everything else was set to defaults, including MU-MIMO enabled. Given the 4x4-to-4x4 nature of the link, MU-MIMO doesn't come into play.
Only one computer was connected via Gigabit Ethernet at each end of the bridge. Baseline tests using Ethernet between the two computers both equipped with TP-LINK TG-3468 NICs show the Ethernet link capable of a bit over 940 Mbps in both directions with each direction run separately. So the hardwired part of the link shouldn't be a limiting factor. We have yet to observe any 4x4 router hitting its maximum specified link rate in these bridge tests. The highest link rate reported by the router in bridge mode was 1559 Mbps (vs. the specified maximum of 1733 Mbps).
The Simultaneous up and downlink tests yielded 950 Mbps total throughput with a little less than 2-to-1 difference between down and uplink throughput as the ixChairot plot shows. The TP-LINK Archer C2600 produced 798 Mbps for its 4x4 test, with its downlink throughput about 2X uplink.
NETGEAR R7500v2 four stream throughput - simultaneous up/downlink
Separate up and downlink tests for the R7500v2 yielded 780 Mbps uplink and 843 Mbps downlink vs. 652 Mbps uplink and 730 Mbps downlink for the TP-LINK. The composite plot shows very consistent througput in each direction.
NETGEAR R7500v2 four stream throughput - up and downlink
A second pair of clients was plugged into the router and bridge to see if a second connection pair would yield higher throughput and to ensure that the single Gigabit Ethernet connection was not limiting results. The plot shows a total 1130 Mbps throughput, about 19% more than the single-pair simultaneous uplink / downlink test above. It also shows throughput not evenly distributed.
NETGEAR R7500v2 four stream throughput - simultaneous up/downlink, four computers
The same test procedure, most recently described in the TP-LINK Archer C2600 review, has been used to test all MU-MIMO enabled routers. The same three Xiaomi Mi Note Pro smartphones used in that review were used to test the R7500v2.
The first test used the triangle configuration, with about 6 feet between the router and each phone. This arrangement is intended to maximize the router's ability to get optimum beamforming for each client by maximizing client-to-client separation at short range. Simply put, the better the beamforming, the better throughput to each client can be optimized.
Due to test space limitations, positions were one client in front, one in back and one on the right side (facing router front). All were about 6 feet from the router.
The chart below shows throughput difference between MU-MIMO disabled and enabled for each client and for all three total. Throughput significantly improved for each client, with a total overall throughput gain just over 100% (slightly over twice as fast). While the percent change on the TP-LINK C2600 was just shy of 200%, the R7500v2 had a total throughput of 533 Mbps with MU-MIMO enabled compared to the TP-LINK's 391 Mbps.
MU-MIMO Throughput change - Triangle
The "All Front" test is meant to be a MU-MIMO torture test because it minimizes client-to-client distance. When clients are close together, it should be more difficult to optimize beamforming for each client.
The test positions all three devices on a rack in front of the router about 6 feet away. This doesn't look like much of a torture test, with higher individual and total throughput gain than the "ideal" triangle arrangement. Total throughput gain was only 65% compared to testing with MU-MIMO off. The corresponding test for the TP-LINK yielded a 330% change, but that's primarily due to the higher throughput achieved by the R7500v2 - both with MU-MIMO on and off. The R7500v2 also had significantly better performance with MU-MIMO off than the TP-LINK, so percentage gains were lower.
MU-MIMO Throughput change - All Front
The last test looks at how MU-MIMO might work in a more real-world home situation with devices in different rooms. This test kept one phone on the rack in the same room as the router, the second phone moved to a nearby bedroom about 25 feet and a few sheetrock walls away and the third located on a table at the far end of an adjacent hallway.
MU-MIMO 3 Room test floorplan
In this test, MU-MIMO provided only 20% throughput gain. In the "Guest" location, better throughput was achieved with MU-MIMO off than with it enabled. By comparison, the TP-LINK showed throughput improvement in each room with a total throughput change of 200% for this test. Note the individual room throughputs with MU-MIMO disabled on the TP-LINK C2600 were significantly lower than the corresponding MU-MIMO off tests on the R7500v2.