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.
Please help me with this... Why a radio station can be broadcast to a whole city from a single antenna, whereas a mobile phone system needs a network of basestations?
Thanks,,,
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Tried replacing the OEM speakers in my vehicle with a set of aftermarkets ...without exchanging the OEM head unit. Terrible idea, and I...
Apart from the 30 some ought bands of EQ, pretty lights, phase control, time alignment, etc, what makes a receiver superior to another in terms of sound quality only?
Clarion. McIntosh. Nakamichi. All of these manufacturers carry dead heads; that is receivers with no internal amplification...
I don't know what it is and how it works but websites such as waptrick.com seems different when seen from a PC.I can't even download things.Is there any way to access such websites.
Homework Statement
https://www.icloud.com/photostream/#AE5oqs3qHTNWQ;B21C49F3-02FB-4EA3-8CE5-D1E2C1FA7C49
Homework Equations
The Attempt at a Solution
https://www.icloud.com/photostream/#AE5oqs3qHTNWQ;A55D9431-FD6D-4884-9AFC-C4D7C8E39AF1
What would happen if I shorted the ends of a mobile phone charger (in both the cases when input is 110V or 220V)?
I was considering using the terminals of a charger as a dc source for any experiment I might want to do at home (batteries would be too expensive), and wondered whether it was a...
Homework Statement
A light smooth pulley is attached to a support a fixed height above the ground. An inextensible string passes over the pulley and carries a mass 4m on one side. The other end of the string supports a similar mobile pulley; over this passes a second string, carrying masses of...
Is it risky to use the mobile phones while lighting occurs outside?
There's a general belief that you should not use mobile phones while it is lighting outside. Is it true?? Is there any logic behind it?
Hello
I was patent examiner on the Portuguese patent office for 3 years and we have a lot of perpetua mobile applications, so I wanted to find now, the theoretical misunderstanding I'm missing here
Imagine you have a track (on a table, on the xOy plane) on which a metal ball would...
Hey guys,
Does anyone know about how much transmission power is outputted from a cell phone call? I have read it's around 100 mW (depending on distance from the tower), anyone ever verified this?
I want to try and use the signal created by a phone call (to detect when a phone call is...
In the linked article,
http://pubs.acs.org/doi/abs/10.1021/jp036735i
the authors describe the generation of "free" or "mobile" OH radicals on surface fluorinated TiO2,
\text{Ti}-\text{F}+\text{H}_2\text{O}~(\text{or }\text{OH}^-)+h_\text{vb}^+\longrightarrow...
I have used many mobile phones and controlled volume on them but I have never been able to figure out how the volume increases or decreases, i.e, what actually happens in a circuit board or other parts present in the phones when we are controlling the volume which ultimately leads to speakers...
A fresh publication (few days ago) in Physical Review (American Physical Society):
http://prd.aps.org/abstract/PRD/v87/i2/e025021
Abstract: <skipped/technical> The suggested “zero-point-driven” devices — which have no internally moving parts — correspond to a perpetuum mobile of a new...
Hi,
I am working with the vibration motor in smartphone. I want to calculate to force comes from the vibration motor through time. In this case, I only measure the force in 3 direction, like x, y and z axes. I expect it has sinuous form but I don't know exactly the mathematics equation to...
Hello there,
I'm a beginner at ROS and I've some questions regarding multisensor fusion. I am currently working on a robot (Pioneer P3-AT) with a monocular vision and Hokuyo LRF without an a priori map. However, I am unclear about how to apply the proposed algorithms like EKF, Bayesian, etc...
My current project is as follows:
Designing a system that will be mounted to a truck that will be traveling down the equivalent of a dirt road. Part of the system is an ingredient bin that is rigidly mounted to load cells. The loads cells are a cantileaverd beam type. The primary...
Dear Experts
I bought a single-AA battery emergency cell phone charger.
It is rated at :
output : 5.6 v +/- 5%
current : 400ma
I plugged it to my samsung note and the phone detected the current and showed it was charging.
At that time, the battery was charging from 75% level...
I just got back to the States and haven't had a cell phone here for 2 years. I'm sort of debating between an iPhone4s and an Android based phone. After doing some research I feel like the Android is the clear choice but was curious as to what others though about these two options or other...
Hello,
i need information who know or advise where i can to find literature, how to caltucalate this.
1. I need information how to caltucalte load (snow, wind and other forces) which can keep this roof, and
2. how to choose dampers which keef roof.
Maybe anyone know how to calculate this...
I am interested in getting a T-Mobile Mobile Hotspot and I was wondering if anyone else uses one. I am also wondering about signal strength and range. Also, in my apartment building the signal strength of T-Mobile's 4G network drops to zero on my smartphone. Does anyone know if a mobile hot spot...
Many of us might have used compilers on our personal computers.But does anyone know of C++ compilers for handheld devices.They would help us compile programs on the go.
Wireless and Mobile Networks - Mobile transfer between networks with direct routing
In this setting: // HENCE my textbook briefly says, but not clarify well
1)
Anchor Foreign Agent is the Foreign Agent in that foreign network where the mobile node was first found...
well,
when mobile node...
I got an SMS educating people how to find out the presence of a hidden cam in a trial room of a textile showroom or bathroom. It goes like this :- "If you can't make a call in the room,the there is a hidden cam. This is due to the interference of the fibre optic with the signal transfer."...
So, my goal is to be able to take two walkie talkies and put one of them on a near space balloon and have a microcontroller send data through the walkie talkie on the balloon down to the one on earth. I'm not sure it would reach all the way back to Earth so I thought of putting a small linear...
Hi friends, I have a samsung mobile charger with specifications as
Input: 150-300V AC and 0.15A
Output: 4.75V DC and 0.55A
So now by P=VI
the input power is 36W (taking 240V AC and unity PF)
and output power is 2.6W.
So my doubt is why there is such difference the power of i/p and o/p...
I'm on mobile so I can't use latex..
sin^2 theta - cos^2 theta is not the same thing as one?
If I had a problem say... 1 + cos^2 theta would that equal to sin^2 theta? Or -sin^2 theta? Thanks
I don't know where the 1/2 comes from in the third image.
If I set mu total(up) = mu total up (0), I don't get the 1/2. I'm missing something very simple here.
http://i111.photobucket.com/albums/n149/camarolt4z28/IMG_20110325_214532.jpg?t=1301107797...
Homework Statement
Homework Equations
-
The Attempt at a Solution
I've tried to calculate moment counter clockwise,
0.4 * 10 (Fg of the yellow piece) + 0.6* 50 = 34 N cm
this is how far I got...
I don't know how to proceed from here on..
please help ;)
and sorry for my english
and sorry if...
Are "rockers" and "rollers" mobile support?
I'm reading about trusses and trying to understand this sentence:
.
I presume they mean mobile support that only has 1 resistance direction. Am I correct?
Hi,
I am working on a case with a flexible cylinder with a flow of air inside and a cross flow of water. This is a fluid structure interaction case and the case is such that I can define the natural frequency of the air inside the cylinder and that would then be used to solve the structure...
Hi,
What methods are used for applying suspension to robotics? I'm designing a surface surveyor, so I want minimal disturbance created by the surface is it travelling.
I thought tracks would remove some disturbance rather than 4 single wheels. However I believe these will still receive...
Homework Statement
Introduction
You are part of a team working on a software system for a mobile phone company. You have been asked to write a class capable of storing the details of a transmitter.
The class will need fields to store the x,y coordinates of the transmitter and the...
Hi,
Am new on this forum.I am about to start my final year in electronics and telecommunication and i am planning for my final year project a research on how traffic (signaling) in a specific cell in a cellular network can be sent to another cell when there is a huge congestion like in a...
Homework Statement
Is there a diode in Tv / Microwave / Mobile ? if it is then for what purpose the diode is there ?
Homework Equations
I got an assignment to find the list of those projects in which diodes are used also mention the purpose of diodes in these projects , I've found 8...
Hi everybody, I have developed a unique concept seatbelt system and automobile cellphone holder system, which when installed in a vehicle will never let drivers to drive the vehicle and talk on cellphones without handsfree and the innovative seatbelt concept with which a driver will be unable to...
Homework Statement
The mobile is in equilibrium. The fish B weighs
27 oz. Determine the weights of fish A, C and D.
(The weights of the crossbars are negligible).
Homework Equations
Moment = Force*Distance
The Attempt at a Solution
My idea here is to use the moments about each...
in chem. class asked the question nd he ignored me, i hope smeone here can help me? wht are the properties of electrolytes nd how do yu kno they coduct electcity nd also how ud yu determinet lowest freezing eezing poin
Hey, is this really possible?
If yes then should I avoid using mobile phones outside or even in-car?
Seems to me that there should be some danger signs on phones then...
Mobile phones=potential killers?
mobile "lights"
I have seen some light making stickers sold that can be put on your mobile and they emit light when you talk. Am I right that they will lower my chances of getting connected when I am far from the antenna? I mean they must somehow make signal weaker, don;t they?
I was searching about the possibility of building a simple mobile phone, but I found an old topic here indicating that this is pointless and hard.
Actually I want to make a mobile phone which only receives the incoming ring and vibrates.
I am asking about the possibility of doing this ? It...
So recently i just got interested in communication related careers that pertain to the field of engineering, so i was wondering would this be more related to computational engineering or electrical engineering
thanks in advance
Hi,
I am looking for information on a concept I am writing software for. Since I don't know much about EE, I though I'd get suggestions.
I wanted to know that best setup I could use for a short range point to multipoint broadcast. The example I have is go-cart racing.
Suppose you are...
ALCATEL OT511 launched around 2001,
While Alcatel no longer support this product, there are still heaps of user still want to use it.
I want to reproduce the electronic circuit for this mobile phone using new components, thus making it simpler, and if possible I would place colour OLED...
what are the main differences between the 2nd generation (GSM) system and the 4th generation, in terms of:
-the type of modulation used.
-multiplexing with the base station.
-bit rate and bandwidth given for each supscriber.
- the complexity of the system.
if you could provide links for...