What is Cell phones: Definition and 35 Discussions
A mobile phone, cellular phone, cell phone, cellphone, handphone, or hand phone, sometimes shortened to simply mobile, cell or just phone, is a portable telephone that can make and receive calls over a radio frequency link while the user is moving within a telephone service area. The radio frequency link establishes a connection to the switching systems of a mobile phone operator, which provides access to the public switched telephone network (PSTN). Modern mobile telephone services use a cellular network architecture and, therefore, mobile telephones are called cellular telephones or cell phones in North America. In addition to telephony, digital mobile phones (2G) support a variety of other services, such as text messaging, MMS, email, Internet access, short-range wireless communications (infrared, Bluetooth), business applications, video games and digital photography. Mobile phones offering only those capabilities are known as feature phones; mobile phones which offer greatly advanced computing capabilities are referred to as smartphones.
The development of metal-oxide-semiconductor (MOS) large-scale integration (LSI) technology, information theory and cellular networking led to the development of affordable mobile communications. The first handheld mobile phone was demonstrated by John F. Mitchell and Martin Cooper of Motorola in 1973, using a handset weighing c. 2 kilograms (4.4 lbs). In 1979, Nippon Telegraph and Telephone (NTT) launched the world's first cellular network in Japan. In 1983, the DynaTAC 8000x was the first commercially available handheld mobile phone. From 1983 to 2014, worldwide mobile phone subscriptions grew to over seven billion; enough to provide one for every person on Earth. In the first quarter of 2016, the top smartphone developers worldwide were Samsung, Apple and Huawei; smartphone sales represented 78 percent of total mobile phone sales. For feature phones (slang: "dumbphones") as of 2016, the top-selling brands were Samsung, Nokia and Alcatel.
I am doing a series of videos on the history of electricity and I am working on a video on Volta and the first battery.
Anyway, I want to compare the voltaic pile to a typical li-ion battery running my iPhone. Now the voltaic pile could easily create 20 V of potential but it had high...
Hello, lovely people. I was wondering if anyone knows what kind of battery Marty Cooper used for the very first cell (mobile) phone call in 1973? I know that by the 80s they were using Nickel-Cadmium batteries but I don't know about that first one.
Thanks in advance,
Kathy
I am very confused with the 3G, 4G, LTE, UTMS, WCDMA terms... Hope someone could shed some light on it. I think complication arises when marketing people start to use these terms interchangeably?
Below is my interpretation, is that correct? Would someone be kind enough to make some comments...
I know quite a bit about tracking cell phones that are network contract phones. I need to know if it is possible to track a prepaid cell phone. I have heard that there are apps you can down load to a prepaid and there is a pay site that can then track the app on the phone.
Has anyone had any...
There are now more active cell phones than humans. (?) The camera lenses of cell phones can detect cosmic rays. An app has been created that stores such detections in a data base. The app has been used in Iceland, Uzbekistan, and Uganda. There is no apparent practical use, it is for...
Consider two adjacent people speaking in cell phones. Why the signals don't interfere with one another? Does each phone communicate with a distinct frequency? If so, how?
Hello,
I need help understanding how exactly cell phones work, like the channels, frequencies, and grid system. I researched a lot but still don't get it, could some one please dumb it down for me :$ I need help ASAP b/c I have an assignment due tmrw. Thankyou so much. Basically, just talk...
Quantum "Cell Phones?"
Earlier today, I was thinking, what if we could use Quantum mechanics to have lighting fast cell phone access? How it could work is you could have one particle in the Cell Phone tower (which could now be just a room.) That was entangled with the particle in your cell...
I remember reading on this forum (probably) about how it was physically impossible for cell phones to cause damage to DNA. A microwave photon has energy in the meV range. My biology and chemistry aren't all that great, and what little I could properly google gave me the idea that molecular bonds...
Hypothetically, could the transmitter-receiver systems in cell phones communicate directly among other such systems at a range comparable to the range they can communicate with towers?
With 4G bandwidth?
In an emergency could scattered cell phones form a communications network if properly programed without need for relay towers? I'm guessing such a system might have severe limitations but if the software was built in it might be an inexpensive way to keep communications going during an...
i mean when data is sent from the network tower to the cell phone,can the data be detected by any other device?can the wave be concentrated in a particular direction(particular device) specifically...
I have a few questions/thoughts about microwaves ovens and cell phones that I'm hoping someone here can help with.
Microwaves ovens and cell phones both use around the same range of frequencies. But microwave ovens use way more power. Ovens about 500W, cell phones at most 2W. More power...
I was playing with Wolfram|Alpha, and I typed in my ten-digit phone number. And it was prime! I have a prime cell phone number!
Of course, I tried this with other numbers... my SSN isn't prime, and neither is my dad's phone number. My seven-digit phone number can be divided by two square...
I was using my iPhone when I got to thinking about how amazing it is that so much information can be transferred all with electromagnetism.
I was in a room with 500 other iphones and I could not connect at all.
is this because AT&T could not support 500 people on the same tower?
if someone...
A couple of decades ago it was feared that the Dutch economy would slowly smother in the traffic jams. The invention of the cell phone however appeared to have countered that. People just continue doing business by cell phone, while waiting in the traffic jams.
I just discovered that cell...
This will be the next thing that one is not supposed to while driving.
Air Writing: Next Big Thing in Cell Phones?
http://news.yahoo.com/s/livescience/20090610/sc_livescience/airwritingnextbigthingincellphones
ive noticed several times that when I am watching tv, and my phone rings, that my ringtone will actually play through my tv speakers. does anyone know why that happens?? thanks.
Researchers have found that cell phone signals can alter four essential features of fertile, grade A sperm: 1. Mobility -- How well they move; 2. Viability -- How tough they are; 3. Sperm count -- How many there are; 4. Morphology -- Proper composition.
In men who use cell phones, multiple...
While I'm not at all surprised by the results of the study reported in this article with regard to how badly distracted drivers are while on the cell phone, even hands-free, I am a bit surprised it was so much different from having a chatty passenger in the car. I would have thought a passenger...
The spectrum for cell phones is typically in the 850 MHz range. E=hv yields around 3.515E-6 eV. The lowest natural state electron binding energy is on the order of 10 eV >> 3.515E-6. Is this enough to dispel the "correlation"? Are there any other particle interaction mechanisms that would...
Has anybody heard of this myth/urban lengend? Any thoughts on how feasible it is?
This only applies to cars that can be unlocked by that remote button on your key ring. Should you lock your keys in the car and the spare keys are home, and you don't have "OnStar," here's your answer to the...
I keep seeing all of these cell phone ads that only talk about playing music, as if that is the only reason to buy one. I thought you were supposed to talk on them.
What do you buy a cell phone for?
These guys dress up like giant cell phones and then attack and destroy other people's cell phones. :rofl: :rofl: :rofl:
http://www.phonebashing.com/
If this is for real, there will be a judge who will also find this tremendously funny. They may think this is fun and games, but it is still...
Don't you?
After having a cell phone for about 3 years, I have realized that I am sick of them. I hate having to take calls and talking to people. If I'm not home, what makes people think I want to talk? All talking should happen in-home with a big handlebar up to your ear and a cord running...
I just wanted to start this thread about the risks of using cell phones. Today there was a new story in the BBC http://news.bbc.co.uk/2/hi/health/4432755.stm
This can only make me laugh since the wavelength of the radiation can in no way affect the cells in the brain. What was this Swedish...
I noticed recently that just before my cell phone rings I can hear a 100 Hz or so buzzing from the speaker of a certain radio alarm clock of mine. I have also seen this sort of thing take down factory systems when standing near unprotected control centers. I know one factory engineer that this...
http://www.popsci.com/popsci/medicine/article/0,12543,573349,00.html .
I try to avoid using cell phones. I figure I'm exposed to enough radiation daily, and using a cell phone is unnecessary.
How often do you we hear things we want to hear on cell phones anyways? It's usually news about...