As a MSc. candidate, I should be executing some kind of experiment, you should think. Yeah, you're right.
I'm working with Wireless Communications standards at the moment (maybe you just deduced it from the blog's title, didn't you?), more especifically on the IEEE 802.11g WiFi standard.
For those of you wich have some base on this field, WiFi can work at different channels, 11 are available for FCC compliants, 13 for ETSI. Most of them overlaps each other, which results in interference when devices use frequency-close channels.
You then may ask: are there any channels that don't overlap, so that no interference is present? The answer is yes... and no. As we pick channels that are 25MHz away from each other (5 channels of difference) we have a clear channel. As factory default is usually set in channel 6, if you feel that your neighborhood is crowded with WiFi nets, you should set your devices to channel 1 or 11.
Back to my experiment... I'm checking how strong is the interference in nets that are in the same indoor space, and started with 2 nets, both at channel 6. Results were that interference is present and reduces a lot the throughput and channel capacity. So I moved one net to channel 8... results were similar, but with less interference. Then came channel 11, for conclusion...
And no communication was possible!! The non-overlapped channels led to a total-wireless-massacre, no one survived. I tried to make it work for 15 days and nothing came out of it. As I lifted my white flag, and went to the Google altar, I found an article that presents exactly what I'm telling you and presented to me the experession Near-Far effect.
It happens with almost any kind of radio device, as they found themselves near to another device that works in close frequency and close distance... tendency is that the devices try to lock the signal and get confused, not knowing whom to answer to.
Trying not to step on my shoelashes, I'll stop here as I'm trying to get more information on that.
This post works as a warning: keep your wireless devices away from each other, they just don't get along ;)
I'm working with Wireless Communications standards at the moment (maybe you just deduced it from the blog's title, didn't you?), more especifically on the IEEE 802.11g WiFi standard.
For those of you wich have some base on this field, WiFi can work at different channels, 11 are available for FCC compliants, 13 for ETSI. Most of them overlaps each other, which results in interference when devices use frequency-close channels.
You then may ask: are there any channels that don't overlap, so that no interference is present? The answer is yes... and no. As we pick channels that are 25MHz away from each other (5 channels of difference) we have a clear channel. As factory default is usually set in channel 6, if you feel that your neighborhood is crowded with WiFi nets, you should set your devices to channel 1 or 11.
Back to my experiment... I'm checking how strong is the interference in nets that are in the same indoor space, and started with 2 nets, both at channel 6. Results were that interference is present and reduces a lot the throughput and channel capacity. So I moved one net to channel 8... results were similar, but with less interference. Then came channel 11, for conclusion...
And no communication was possible!! The non-overlapped channels led to a total-wireless-massacre, no one survived. I tried to make it work for 15 days and nothing came out of it. As I lifted my white flag, and went to the Google altar, I found an article that presents exactly what I'm telling you and presented to me the experession Near-Far effect.
It happens with almost any kind of radio device, as they found themselves near to another device that works in close frequency and close distance... tendency is that the devices try to lock the signal and get confused, not knowing whom to answer to.
Trying not to step on my shoelashes, I'll stop here as I'm trying to get more information on that.
This post works as a warning: keep your wireless devices away from each other, they just don't get along ;)
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