Kondrath Posted December 13, 2011 Share Posted December 13, 2011 I just bought my first modern router. I was using an old D-Link DI-524 since '04. Anyway, I'm now using a Linksys e2000 running Tomato. I noticed something called "Noise Floor". My laptop is sitting literally a few inches from the router and it hasn't gotten any higher than -29 dBm. It should be higher, right? I've tried every single channel and nothing helps. I don't have any things that would interfere, as far as I know. But I do live in an apartment complex and it detects another AP on Channel six at -53 dBm and one on channel 11 on -83 dBm. I don't really know what any of this means, but I'm pretty sure it shouldn't be that low. I think... Ideas? Link to comment Share on other sites More sharing options...
cork1958 Posted December 13, 2011 Share Posted December 13, 2011 Personally, Don't have a clue as to what any of those numbers mean and am glad you asked it, but I've also never been concerned about it as my E2000 with Tomato works perfectly. While anyone is at it, how about explaining what the RSSI, Quality and TX/RX rate mean. I can kind of figure out what the quality one is all about. My noise floor is at -99dbm and I'm about 6 feet from it although there is a thin wall between me and router. Router is in hallway closet in basement and I'm in family room in basement. Nothing is showing up under those lines I was asking about explaining. Link to comment Share on other sites More sharing options...
srbeen Posted December 13, 2011 Share Posted December 13, 2011 any signal below -91dB will not be seen. Its the 'floor' of your electrical noise in the environment, and if your signal goes below the floor its not recognizable. You can imagine that -29dB is 'better' or 'higher' or 'stronger' than -91 and you are correct. If you go far enough away, that the signal drops to -100dB, you will NOT have internet. in electronics sense, -30dB is damn good. Nominal is around -45dB to -65dB usually. not familiar with tomato and how it actually calculates the noise floor, but as long as you are 20dB above it there should be no problems with the internet. If your hungry for more info : http://en.wikipedia.org/wiki/Decibel Kondrath 1 Share Link to comment Share on other sites More sharing options...
Kondrath Posted December 13, 2011 Author Share Posted December 13, 2011 Well, I'm not too confident about it so far. It seems to be getting worse / same range as my junky DI-524. Moving about 20-35ft away with nothing physically blocking the router's parth, the Quality drops to the 20s. @Cork, I think TX/RX is the Transfer and Receive rate Link to comment Share on other sites More sharing options...
cork1958 Posted December 13, 2011 Share Posted December 13, 2011 Well, I'm not too confident about it so far. It seems to be getting worse / same range as my junky DI-524. Moving about 20-35ft away with nothing physically blocking the router's parth, the Quality drops to the 20s. @Cork, I think TX/RX is the Transfer and Receive rate As soon as I typed that, I thought that's what it stood for. Link to comment Share on other sites More sharing options...
srbeen Posted December 13, 2011 Share Posted December 13, 2011 To follow up on your finding of other AP. it means that the person with -56dB is closer to you than the person with -84dB. the m is reference to a milliwatt of power. depending on the item and environment this could be referenced to sound pressure, to voltage, to current, to almost anything else that involves an antenna of some sort. So, at 1mW of output power, you wold have a signal strength of 0dBm. The most you are legally allowed to radiate without a permit is 1W of power. this is 1/10 the legal possible max. You can use this information to design a higher gain or focused antenna, and prove it is providing gain (increase distance with equal power, or increased power with equal distance) I highly doubt the router will see higher than -20dB signal though, you will likely introduce clipping when its being processed and result in packet loss. Link to comment Share on other sites More sharing options...
Kondrath Posted December 13, 2011 Author Share Posted December 13, 2011 I sort of get it, but not really. Moving my laptop one more foot away causes it to go from -29 to -40s. Is this router a piece of junk? lol? Link to comment Share on other sites More sharing options...
srbeen Posted December 13, 2011 Share Posted December 13, 2011 Personally, Don't have a clue as to what any of those numbers mean and am glad you asked it, but I've also never been concerned about it as my E2000 with Tomato works perfectly. While anyone is at it, how about explaining what the RSSI, Quality and TX/RX rate mean. I can kind of figure out what the quality one is all about. My noise floor is at -99dbm and I'm about 6 feet from it although there is a thin wall between me and router. Router is in hallway closet in basement and I'm in family room in basement. Nothing is showing up under those lines I was asking about explaining. your house is a lot less 'noisy' than the OP's. you have almost 10dBm lower noise floor, or a better transceiver/antenna in your router version. less interference/microwaves/cordless phones/wifi points/GPS/anything else that uses the 2.4GHz spectrum would give you a lower noise floor, which would let you detect a 'weaker' signal. I sort of get it, but not really. Moving my laptop one more foot away causes it to go from -29 to -40s. Is this router a piece of junk? lol? You are changing the electronic field. likely moving the screen would change the signal strength too as the antenna wraps around the laptop LCD.keep the laptop in the same place. and spin it 10 degrees. check strength. spin 10 more.. do that 36 times and see, the strength will likely vary 5-30dB at points.Think of when you had rabbit ears on the TV or tried to get a clear sound on the radio. Same principal... you could likely go down/up a floor, and angling the screen correctly have a -30dB-range signal. where as being 1 foot away and moving it 30 degrees causes you to drop 13dB of strength. The higher the strength the better the connection = the faster the speeds. The only time this would become an issue is if you drop close to the noise floor. Link to comment Share on other sites More sharing options...
Kondrath Posted December 13, 2011 Author Share Posted December 13, 2011 Alright, I understand. An inch from the router, the highest I can get it is about -28. In another room, the lowest it has gone is -63. I get 9.6mbps (10mbps connection) an inch away and get 9.06 in the other room. I suppose that's normal. Darn, I thought I'd be seeing a great improvement over my old router. Oh well, as long as it doesn't randomly cut off while I'm downloading... Link to comment Share on other sites More sharing options...
cork1958 Posted December 13, 2011 Share Posted December 13, 2011 Alright, I understand. An inch from the router, the highest I can get it is about -28. In another room, the lowest it has gone is -63. I get 9.6mbps (10mbps connection) an inch away and get 9.06 in the other room. I suppose that's normal. Darn, I thought I'd be seeing a great improvement over my old router. Oh well, as long as it doesn't randomly cut off while I'm downloading... As said by srbeen: "The higher the strength the better the connection = the faster the speeds." Does a higher dbm, meaning my -99 vs. OP's -91, mean my signal is technically better than OP's and if so, when OP posted the above stuff, "An inch from the router, the highest I can get it is about -28. In another room, the lowest it has gone is -63" that means he was actually getting a better signal being further away, at that time? That would mean OP technically worded it backwards in his remarks about highest and lowest, right? -28 would be lowest and -63 would be highest? We want HIGHEST number, right? I knew I shouldn't have started reading this topic!! Link to comment Share on other sites More sharing options...
Kondrath Posted December 13, 2011 Author Share Posted December 13, 2011 lol.The closer you get to -99, the worse the connection. So if I ever got to -99 or -100, the internet would cut out. Link to comment Share on other sites More sharing options...
srbeen Posted December 14, 2011 Share Posted December 14, 2011 Alright, I understand. An inch from the router, the highest I can get it is about -28. In another room, the lowest it has gone is -63. I get 9.6mbps (10mbps connection) an inch away and get 9.06 in the other room. I suppose that's normal. Darn, I thought I'd be seeing a great improvement over my old router. Oh well, as long as it doesn't randomly cut off while I'm downloading... how can you get better than the theoretical max? wireless G is good for 54Mbps, which is around 7MB/s. Wireless N can do 150Mbps, which is about 18MB/s. Heres the trick you don't know. This is all simplex speeds. Meaning only ONE direction at a time. So if you are uploading and downloading you will get 18MB/s. If you are just downloading you will get closer to 9MB/s Dual band can do 300Mbit bidirectional - about 38MB/s each way simultaneously - you need a special wifi card for this though. your connection won't suffer until you are 20dB range of the noise floor, with routers its likely more like 5-10dB as they are digital and more sensitive. if its -91dB noise floor anything from -75dB and lower may cause drop outs, high pings, etc. Link to comment Share on other sites More sharing options...
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