Poor Range/strength With Two Routers Running

I am running a network with my internet connection coming into a Linksys N router, which then feeds another Linksys AC router. This creates two distinct networks which my intent is to have isolated from each other. It seems to be working pretty well. I only really use the second network (AC) day to day, and it runs dual band. One issue I am having though is router range. I have them set up physically side by side, and in using inSSIDer to scan, I can see that no signals are overlapping (including my neighbors WiFi). Yet, when I have them both broadcasting, I lose all range on my networks. I have it set up in my basement, and I barely have a signal on the 2nd floor (2 storey house), and once I go outside it's gone. If I disable the N network, the range on the AC gets way way better. I barely use the AC network, so this solves my problem, but my question is why would this happen? If everything is on separate channels, shouldn't the interference be eliminated? Or is there something else I'm missing?

 

This could be your problem - or a part of it. Even though you have them set up on different channels (and you need to verify that), radio antennas are cut to a specific wavelength for the frequencies they are used for. This allows the antennas to absorb and transmit more efficiently. 802.11n and 11ac use the same frequencies so the antennas may be interfering with each other - this is especially true if the antennas are parallel to each other. I would separate the two wifi routers as much as possible, by 3 feet at the very minimum - opposite sides of the room would be good, and at different heights too. And orient the antennas on different planes so they are not all parallel to each other. If your wireless routers have internal antennas you cannot move about, turn one of the wireless routers 90° from the other.

Most WAPs or APs (wireless access points) are designed to be placed in a relatively high point of a facility, such on the upper level or on a high shelf. So if you could move your wireless routers to the 2nd floor, you probably would have better total coverage.

Make sure your channels are separated by 5 points - so for example, use changes 1 and 6 or 6 and 11.

You also need to study your environment. Make sure other sources of interference are as far away as possible, including other PCs, microwave ovens, cordless phones. Ensure the WAPs are not sitting next to large metal objects, including large ventilation ducts in an adjacent wall or blocking "line of sight" to your 2nd floor devices. Numbers of walls/floors/ceilings between the two endpoints impact signal strength - especially if there are metal pipes, metal ductwork and electrical wires in those barriers. The composition of those barriers matters too - that is, thick brick walls (as often found on bottom floors of home)can absorb/block RF more than simple sheetrock walls.

You may need to look at the wireless adapters on your computers too and perhaps replace them with adapters with external antennas like this or this.

 

Thanks, that's some awesome information. Both routers have internal antennas, and they are actually next to an exterior wall of the basement, which is cinder blocks, so I'll try rotating/moving them around. I can't really move them higher up in the house, as my desktop setup uses Ethernet, which is in proximity to the routers now and I don't want to move everything to a different part of the house just to improve the WiFi. They are currently using Ch 6 and Ch 11 respectively, so there's no overlap. Either way, I'll try out some of the suggestions you noted and see if it gets better. Thanks!

 

Good luck and keep us posted.

 

I ended up disabling the AC network's wireless, and the N900 network got a little better, but it's still struggling. I think I'm going to try out an extender. I started another post with regard to that issue.