By your definition nothing can be digital since the world is analog. Even the bits in your CPU are voltages in transistors. As such, every real life signal can be distorted.
By your definition nothing can be digital since the world is analog. Even the bits in your CPU are voltages in transistors. As such, every real life signal can be distorted.
Lifter@discuss.tchncs.de 3 days ago
The point with digital transfers is that you round it back to either 0 or 1, hoping that no bits are distorted enough to have any loss at all.
gozz@lemmy.world 2 days ago
Exactly. Digital logic, when implemented in analogue, generally have to have forbidden zones where a signal in that range is considerer invalid. Regardless of implementation, digital is about the discretized logic of the system. That is explicitly the whole point of digital: Minor analogue distortion does not change the information content of the signal unless it is so bad as to flip a bit.
CookieOfFortune@lemmy.world 2 days ago
This isn’t true in the general case. In the real world, you can have all kinds of distortions: random noise, time shifts, interference from other signals, etc.
You don’t usually see the effects of these because the protocols are designed with the communication channel characteristics in mind in order to reproduce the original signal.
Using birds is just another communication channel with its own distortion characteristics.
Lifter@discuss.tchncs.de 2 days ago
That’s exactly what they said.
gozz@lemmy.world 2 days ago
Precisely… And digital modulation’s entire purpose is for a digital signal to survive those distortions bit-for-bit perfect. Even if we call the digitally-generated spectrogram digital information, the bird simply did not reproduce it exactly. Whatever time, frequency, and amplitude resolution you apply to the signal, if it’s low enough that the bird reproduced the signal exactly within that discretized scheme, then it simply did not achieve 2 MB/s.
CookieOfFortune@lemmy.world 2 days ago
That’s not really how it works in the real world. Usually you have both bandwidth and noise constraints.
Sure you can send something like a square wave but this isn’t practical for real communication channels. Typically you’re sending many sine waves in parallel with multiple amplitudes and phase offsets to represent a sequence of bits (QAM). Then on top of that you’d encode the original data with both a randomizer (to prevent long runs from looking like nothing) and error correction. So usually the system can handle some level of distortion.
What you’re hoping is that by the time the data reaches the user (really, Layer 3), all the errors have already been handled and you never see any issues.
The bird is just another type of noisy channel with its own distortion characteristics.
Lifter@discuss.tchncs.de 2 days ago
You are not addressing my critique of your statement, just piling on a bunch of useless extra knowledge just so that you can feel superior.
socsa@piefed.social 2 days ago
The point is that at the physical layer you still have a well defined log likelihood test to produce digital information. That's why QAM lasted so long even though it is not power efficient - because it has an analytical likelihood function.
This is the boundary between digital and analog communications. Since he did not use a digital modulation scheme, this would be a form of analog comms
CookieOfFortune@lemmy.world 2 days ago
Why couldn’t you have a likelihood function for the bird?
As a trivial case, you can just say: Does the spectrum look like a bird? Then you’d have a digital channel by your definition for a single bit.
The actual channel bandwidth is obviously higher than that.
Regrettable_incident@lemmy.world 2 days ago
I dunno how you’d use check digits with a bird, but this seems the obvious way to deal with corruption. Or maybe give the bird more treats.