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ADVANCE WIRELESS TELEPHONY

In the year 1973 there was a big change that revolutionized communications in the world, thanks to the arrival of the first handset created by a Motorola executive Martin Cooper which he launched this phone call 800OX DynaTAC

Years later in 1990, Motorola continues to surprise the world with MicroTAC

After a great leap of communications which were originally fully analog and now transmission to the arrival of these phones became digital.

After these new inventions had changed communication in a wired to wireless transmission that brought in if a way to improve both transmission and reception of these phones in addition to the advantages and disadvantages that arise from this form of communication.

Today it is changing the communication which has created a practical way to get people to be better communicated and that through the project dodgeball this service is to give information on the position of some contact with a radius of 1 km where you will find this poderte to meet with your contacts.

also advances in communications have allowed the transmission of data audio and video and this also improved speed, every day of rapidly advancing technologies over time and how much needs you want a cover.

recently

companies Lucent Technologies and Vodafone announced they had completed the first test calls using a global technology of third generation (3G) under the CDMA wireless communication standard (Division Multiple Access Code). Also, a Japanese cell phone announced the adoption a standard wide band WCDMA, that nothing comes close to the idea of \u200b\u200ban extended CDMA in their projects for 3G services, which could begin operating in those days. For its part, Europe manages a proposal from the dominant wireless standard in these markets, the GSM . The wireless communications networks around the world have evolved driven by mobile services. But nevertheless, in every country, every market, and in each government, have worked in different situations and regulations have provided an elaborate map of communication standards and technologies analog and digital connection: AMPS, TDMA, CDMA, GSM, most satellite communication systems.

era begins in 1980 cells. Different developments and new technologies took place during the years 1990 to 2000.

1946 2010 +

PIONEER ERA
	1860-Application of EM waves by James Maxwell
1880	-Demonstration the existence of waves for Henry Rudolf Hertz.
	1890-First Patent wireless by Guglielmo Marconi.
	1905-First transmission of voice and music via wireless link by Reginald Fessenden
	1912 Sinking of the Titanic -emphasizing the importance of wireless communications on the sea lanes in the years following the Navy began establish radio telegraphy.
ERA PPRECELULAR
	1921-The Police Department Detroit directed military exercises with mobile radios.
	1933-In the U.S., there are 4 channels in the 30-40 Mhz.
	1938-In the U.S., regulates regular service.
	Prime trade of mobile telephone systems operated by the Bell system in the U.S..
1948	trade Prime fully automatic mobile telephones in the U.S..
1950	-phones and microwave links are developed.
	1960 - Introduction of trunk lines to radio systems with automatic channels in the U.S..
1970	-mobile phone systems operate in many cities. They used 100 million vehicles.
CELL ERA
	1980 - distribution of analog cellular systems around the world
1990	-distribution of digital phones and dual mode of operation of digital systems .
2000	-Distribution of multimedia services through FPLMTS, IMT-2000, UMTS
2010	-Bandwidth for Wireless Communication

	-Radio over fiber (as well as micro cells over fiber optic )

AMPS Advanced Mobile Phone System (Advanced Mobile Phone System) is a mobile system first generation (1G , analog voice ) developed by Bell Labs . Was first implemented in 1982 in U.S. . It was also implemented England and Japan .

double AMPS uses 832 channels, consisting of 832 single downstream and 832 other simple rise, each with a bandwidth of 30kHz, 200kHz compared to systems like GSM . The frequency band used is from 824 to 849 MHz for the transmission channels and 869 to 894 MHz for the receive channels. Not all channels used for user communication, but there are also channels for control, allocation channels of conversation and to warn of incoming calls.

TDMA stands for Time Division Multiple Access . Technology that delivers the information units in alternate time slots, providing multiple access to a limited number of frequencies. TDMA is a wireless technology second generation that serves high-quality voice and data.

TDMA divides a single channel radio frequency in various time slots. Each person making a call is assigned a specific time slot for transmission which allows multiple users to use the same channel simultaneously without interfering with each other.

Several TDMA-based digital standards such as TDMA D-AMPS (Digital-Advanced Mobile Phone System), TDMA-AMPS D-1900, SCP-1900 (Personal Communication Services), GSM (Global System for Mobile Communication), DCS-1800 (Digital Communications System) and PDC (Personal Digital Cellular).

The code division multiplexing or CDMA is a generic term that defines a wireless air interface based on spread spectrum technology (Spread spectrum). For mobile , CDMA is a multiple access technique specified by TIA as IS-95.

channel of 1.25 MHz of CDMA provides a common resource to the terminal in a system in accordance with their own needs, including voice, fax, data or other applications. In a given time, the portion of the bandwidth that do not use a terminal will be available for another user.

The service short message or SMS ( S hort M essage S ervice ) is a service available on mobile phones that allows the sending of short messages (also known as text messages) between mobile phones, telephones and other handheld devices. SMS was originally designed as part of standard mobile GSM digital , but now is available in a wide variety of networks, including 3G networks .

Bluetooth

is the common name of the industry specification IEEE 802.15.1 , defining a global standard communication that enables wireless transmission of voice and data different devices via a radio link safe.

The Bluetooth specification defines a communication channel of maximum 720 kb / s (1 Mbps of raw capacity) with optimal range of 10 meters (optionally 100 m with repeaters).

DECT Cordless Phone .

DECT is a device Digitally Enhanced Cordless Telecommunications and is an ETSI standard ^* digital cordless phone, almost always used for home or even corporations rather they use GSM technology. DECT can also be used for wireless data transfers. That is, functions may also have a regular cell phone, usually at the base of the phone when this is there is charging this phone because it is like "wireles" or "cordless" also right there you can hear the speaker if desired indicates the number of messages that have (and which is also used as the base answering machine) can set the time, date, among other things.

wireless telephone system based on British Telecom DECT.

As mentioned before the DECT is a wireless device GSM . An important difference between the two systems is that the area of \u200b\u200boperation DECT devices is from 25 to 100 meters , while GSM 2 to 10 km , depending on the needs of each person is system that could serve, for home is obviously advisable DECT short distance by comparison of GSM.

DECT was developed by ETSI, but later adopted by several countries in the world. DECT is used in all countries of Europe and beyond, is used in most of Asia, Australia and South America. America has been off limits for DECT, because another organization the U.S. has different rules or standards, but that could change in the future.

* (ETSI) and European Telecommunications Standards Institute European Telecommunications Standards Institute Telecommunications is a standardization organization the telecommunications industry (equipment manufacturers and network operators) of Europe, with worldwide reach. ETSI was created in 1988 by CEPT (European Conference of Postal and Telecommunications Administrations, CEPT, acronym for its French name Conférence européenne des Administrations des postes et des télécommunications ).

MOBILE PHONE

mobile phone or commonly known as a cell phone (because of the shape of the antenna radiation simulating a honeycomb) is a portable electronic device used in mobile communication.

This device can be divided into three sections to understand its operation, these blocks are: Audio block all frequencies that are that can be grasped by the human ear and can be heard, the block of radio frequencies are the frequencies containing the information sent and received between mobile terminals, and finally there is the CPU block, which is responsible for controlling transmission and reception processes and to control the sound generation process.

RF Module

This is the module to send and receive signals for transmission to air, this is formed primarily by a duplexer or as shown in block diagram as transmit-receive switch As its name suggests is the circuit responsible for separating the signal being received and that which is sending through various channels so that they do not mix.

The RF receiver circuit filters and demodulates (converts the received signals into signals that can recognize the phone) and these signals are the audio block.

RF transmitter circuit has a reverse process to the above circuit and the signal it receives directly from the audio circuit and to modulate their transmission through the media is in a more reliable (s say that no information is lost) and easier.

Then there is the frequency synthesizer block that is responsible for providing both sender and receiver to different frequencies for their work, because there are too many frequencies are sent into the air or are received thereof, and must use the same frequency to convert the RF signals.

Audio Module

This circuit is responsible for managing the sounds of both outbound and inbound to the phone, and this is composed of two main blocks:

Block Audio Receiver, which receives the radio signal receiver and making the filters (ie remove the signs outside the original signal as clear leaving possible) and amplifies it and then send it to the speaker, this circuit also has the call indicator, as its name suggests is responsible for sending a message that an incoming phone call.

transmitter block takes the microphone signal and the filtered and amplified and then send it to the RF transmitter.

Also as shown in the diagram both blocs working together with signals from the control block.

logical control module

The control module is as shown in the block diagram of a small computer that is responsible for sending control signals to both the AF module as the RF.

This module is mainly composed of CPU that is the part that is responsible for processing the data and send it based on control signals.

is composed also two ROMs (read-only memory), which normally contain instructions for the processor to work properly, in turn, also contains a RAM (random access memory) which is where will be stored for a short time the different data to operate the CPU.

Modem (modulator-demodulator) is the one that receives signals from the audio module and transforms them into a language understandable to the CPU, and in turn receives signals from the CPU and transforms them into signals that can occupy Audio frequency module.

The tone generator as its name implies is what creates the different tones heard when pressing a key.

cell controller is responsible for taking input or output signals to the CPU, the input from the keyboard, and output are sent to the driver and this in turn the LCD system in which would be watching the programming on the CPU.