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Cell Phones - Analog vs. Digital
"The point of digital is that it takes alot less power to transmit and if you've got 1 bar or 5, the signal should sound the same.. and there in lies the problem.. with the should. With an analog phone as your signal strength begins to go below 1 bar you start to hear static but you can still understand the person your talking to, though you may need to 'yell over the static'. However, with a digital system when the signal fades, there's no yelling because the signal isn't there, and packets that should be getting to your phone, just get dropped. As a result, Aunt Martha's 'Hello' on a crummy analog connection can still be made out.. but on a digital connection of the same strength might sound like 'He...o' with a gap of silence in the middle. (See my Cell-Phone Switch parody commercial on this site for an example if you don't know what I'm talking about).
Cell phone companies are boasting about how digital is good, but is it really? Analog signals work on the 900MHz band, which goes very well through houses, trees, your neighbors dog, etc. Analog works on the 1.9GHz frequency, which does not go through houses, walls, metal, trees, well at all. The question now becomes, why are they moving to 1.9GHz? The signal length is smaller, and therefore antenas on the phones can be smaller without worrying about chopping the signal from it's full height. However, the cell phone companies need to cover the area better for there to be as much coverage, especially in the city where there is lots of Multi-path (bounces and signal inversions), and buildings to go through. This is the same reason that your 900MHz portable (land line) phone will go further then your 1.2GHz portable phone.. (or it should anyway, but alot of companies are making illegal 1.2GHz phones and putting them on the market).
In addition, back to Aunt Martha, as long as her 'Hello' usually sounds like her 'Hello' on a land line, what difference does it make right? Well, unfortunately, the digital standards we have today are from years past. And while they work, they are by no means clear. If you are looking for clarity, you'll want to stick with an analog phone. For data communications, digital is the way to go. Cell phone companies will tell you that if you're in analog you won't get your voice mail notification and such, but the truth is they COULD do it if they wanted to. They just want you to switch over to digital. Why? For one, it takes less bandwidth off of their access points, so they can get more subscribers on per access point. Each analog cell antenna can carry only 56 simultaneous phone conversations, which just doesn't cut it in heavily populated areas. With digital they compress the signal and as a result can get many more people on a sectoral antenna. Digital cell phones use extreme compression of the sound that they transmit. The compression algorithms used are lossy; they're specifically designed around transmission of human voice to human ears, and take advantage of what the human ear will tolerate and what it won't.
What about the pros for digital? Digital is a bit more secure then analog as you can't hear it just by setting a scanner to the correct frequency, you also have to un-encode it from the digital, and smooth the signal out.
On last thing, the digital system works on 1.9GHz... your home microwave works on 2.4GHz.. It's close enough, you still want to hold that phone next to your head? Remeber what happens to an egg when you put it in the microwave, and then decide.
So with all that said, which do I prefer? I prefer the analog since it has better coverage, and the analog phone will keep the connection better in fringe areas. Digital phones are an all or nothing proposition. They either work or they won't. Analog phones can swish and cut out, without dropping the call. What do Slashdot readers use and like and why?"
In a few years, the analog networks will be completely gone. Hell, a good number of phones sold today do not support analog.
For all its good points, what's the point of analog if I can't use my phone because the battery is dead?
I used to bulls-eye womp-rats in my pants
Yeah, I realize that microwaves are 2.4 ghz, etc. Cell phones are 1.9, yes. However, if there is proof that cell phones cause cancer, or some other awful problem - we haven't seen it yet. Does your head warm up when you're on the phone? Yes. Does it harm you? Don't know, and we might not know for some time.
The microwave comparison is bunk. First, microwave frequencies are chosen to be those best absorbed by food (ie. resonant with molecules such as H2O). Second, the power level of your phone is, at max output, a bit over a watt. The microwave is 600 to 1000 watts beamed into an enclosed space. It's like saying that you shouldn't play with a nerf launcher because getting hit with a rocket-propelled grenade is dangerous.
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"You are not remembered for doing what is expected of you." - Atul Chitnis
Sure, a perfect vinyl record may theoretically sound better than a CD, but when was the last time you saw a perfect vinyl record?
It's hard to be religious when certain people are never incinerated by bolts of lightning.
The signal in an analog phone is still converted into digital pulses at some point along its journey. There's no escaping it. You're either woefully uninformed, or just a really bad troll.
- A.P.
"Remember when the U.S. had a drug problem, and then we declared a War On Drugs, and now you can't buy drugs anymore?"
My repsonse to this is so what? I don't need to stream lossless audio down my cell phone. I want the person on the other end to hear me somewhat clear. If they tune the codec to human voice, around the 150 KHZ range, that's fine.
You know who I think is crazy? All my ex-girlfriends!
Creative math there.
Assuming the magnetron and cell phone have identical spherical radiation patterns, the energy from the magnetron would be about seven times more than the cell phone.
Additionally, the magnetron will penetrate much deeper: 5mm deep into your skull, the cell phone's power will be 400% less, and the magnetron's power will be 15% less. That assumes zero blocking effects from the tissue.
Paranoia and hearsay does not equal fact.
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