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The problem is that if you lose enough bits you get nothing, whereas with FM you just get more static. also it doesn't have to be "pretty much perfect", whatever that means, that's why there's something called error correction.

I deal with Digital and analog signals every day, being at present involved in Emergency communications. The digital repeaters and radios we use do have a striking difference in range. Digital is much less. The manifestation of this is that at high signal strengths, a traditional FM signal and a Digital signal sound for practical purposes, identical. The Digital signal has a more silent background, but for all practical purposes, they are the same.

As the signal strength from one radio to another is decreased, a point comes where hiss is introduced to the received signal. This is the point where what we call "Full Quieting" is lost. It is basically a change in the signal to noise ratio. The signal is fading, and the noise is a larger component of the signal.

A digital signal is not immune to this change in Signal to Noise ratio. It shows Full Quieting until you don't hear it any more.

What happens is at some point, is that this increase in noise makes it impossible for the D to A and A to D converter to do it's job. At this point the signal goes away.

The FM analog signal is still intelligible to human ears long after the digital signal is not.

There have been efforts to alleviate some of the problem by a lot more tolerance, which is to say, allowing the less egregious errors to be passed along as if they were part of a good decode. But now imagine when this happens twice, say one station with a sub par input to a repeater, which then resends the message to other stations, some of which might have non-optimal receiving conditions.

There are some other attempts to allay this problem, such as MELP https://www.vocal.com/speech-c... which instead of a normal digital encoding, the receiving end uses lookup tables of phonemes to reconstruct a person's voice. You can get some pretty weird sounding results. It's hard to determine the fidelity of turining a human voice into a sort of robotic one.

the fading is due to loss of signal strength at distance. there is no "FM fades slowly over distance", the signal, regardless of analog or digital, fades slowly over distance as 1/r^2.

I really have to stop ya for a second. First you say that an FM signal does not slowly fade over distance, then you say thay all fade over distance.

So which is it? FM does not fade? SRSLY, you here just to troll or something? I challenge you to show that FM signals do not fade.

All Radio frequency signals, regardless of origin, race, sexual orientation, or creed, lose signal strength as the distance between a transmitting station and a receiving station is increased. The only part where the rules are a little different is that there is what is called a Near Field, and a Far Field. The size of the near field is related to the frequency , the Near Field becoming smaller as the frequency increases.

it's only a really shitty radio where "nothing happens at a much closer range.". generally that's impossible.

Now you are just playing games I must congratulate you not not only taking my quote out of context,. but quoting only part of my sentence.

Congratulations - in your world, there is no such thing as a digital cliff. Now scoot on over to Wikipedia and inform them how and why the are wrong. Here's the link. https://en.wikipedia.org/wiki/...

So i'd really like to see a system that does that without it being the result of a shit radio that can't do automatic gain control properly, because that sounds exactly like a shit radio with a bad AGC implementation.

So what you are saying is tha

This form of SR enhancement has several important applications. It can be implemented on a wireless router or access point to increase its effective receiving range. Without SR, there would be data that were corrupted beyond repair because too much noise was introduced during transmission from a distant transmitter. With SR, this data can be reconstructed. This can also be used for the lawful interception of wireless transmissions. A receiver can be placed far enough away from the transceiver that is transmitting the data to be intercepted so that it is considered out of range, but by the use of SR it can retrieve the data.

http://www.vocal.com/stochastic_resonance/binary_signals.html

For more info: http://www.vocal.com/stochastic_resonance/index.html

An explanation of its use in discrete time applications: http://www.vocal.com/stochastic_resonance/discrete_time.html

This form of SR enhancement has several important applications. It can be implemented on a wireless router or access point to increase its effective receiving range. Without SR, there would be data that were corrupted beyond repair because too much noise was introduced during transmission from a distant transmitter. With SR, this data can be reconstructed. This can also be used for the lawful interception of wireless transmissions. A receiver can be placed far enough away from the transceiver that is transmitting the data to be intercepted so that it is considered out of range, but by the use of SR it can retrieve the data.

http://www.vocal.com/stochastic_resonance/binary_signals.html

For more info: http://www.vocal.com/stochastic_resonance/index.html

An explanation of its use in discrete time applications: http://www.vocal.com/stochastic_resonance/discrete_time.html

This form of SR enhancement has several important applications. It can be implemented on a wireless router or access point to increase its effective receiving range. Without SR, there would be data that were corrupted beyond repair because too much noise was introduced during transmission from a distant transmitter. With SR, this data can be reconstructed. This can also be used for the lawful interception of wireless transmissions. A receiver can be placed far enough away from the transceiver that is transmitting the data to be intercepted so that it is considered out of range, but by the use of SR it can retrieve the data.

http://www.vocal.com/stochastic_resonance/binary_signals.html

For more info: http://www.vocal.com/stochastic_resonance/index.html

An explanation of its use in discrete time applications: http://www.vocal.com/stochastic_resonance/discrete_time.html

Won't 802.11a signals which operate in three bands all above 5GHz still pass through this stuff normally? I know that 802.11a doesn't pass through walls well anyway, but I would hate to purchase gallons of this stuff at their prices for a false sense of security.

Not to mention also that my cell phone wouldn't work in that room either. This stuff seems to be more trouble than it's worth. Better to build real network security that to depend on physical obstructions.

The 5 GHz U-NII frequency bans is segmented into three 100 MHz bands for operation in the US. The lower band ranges from 5.15 -5.25 GHz, the middle band ranges from 5.25-5.35 GHz and the upper band ranges from 5.725-5.825 GHz.

So odds are a 5.8GHz phone would mess with the upper range of 802.11a.

uh, what? 3G and 2.5G are no dialup modems. they're not some lame coupler taped over your 1989 bag phone.