What Is a GSM Antenna?

What Is a GSM Antenna?

A Global System for Mobile (GSM) antenna is a type of antenna commonly used in mobile phones and cell towers. Global System for Mobile Communications is the most common type of cellular network worldwide. The antenna in a GSM phone allows the device to communicate with another GSM antenna on a cell tower, which then relays the signal to another tower or to another cell phone. GSM service can be used on a number of radio frequencies, depending on the region and technology used.

 Many modern phones with GSM antennas support a variety of these frequencies so that they can be used while traveling.

Most modern mobile phones have an internal GSM antenna, usually contained in or near the bottom of the phone. Some older phones have an external pull-out antenna or a small bump of an antenna on the top of the phone. Both internal and external GSM antennas work in the same way.

Many smartphones have other antennas for additional technologies, such as wireless Internet connections. GSM also can be used to transfer data, for use in email or Web browsing on mobile phones. Many phones have a GSM antenna that is compatible with third-generation (3G) technology for much faster speeds.

Cell phone carriers use much larger antennas as part of their cell sites. These can be mounted high on a tower or structure. A cell phone often is within range of more than one cell site, and it selects one to use for a call or data transfer based on signal strength and congestion. Carriers sometimes will hide a large GSM antenna or disguise it to make it look more appealing.

A GSM antenna also can be found in a laptop, a netbook or a Universal Serial Bus (USB) device. In these cases, the antenna is meant only for data. It usually will use 3G technology to deliver quick wireless Internet service over a GSM network.

In areas with poor coverage, special devices are designed to increase or extend the cell phone signal, typically for more reliable indoor use. These devices, which can be called femtocells, microcells or GSM booster antennas, have larger antennas than those found on mobile phones but smaller than those of a traditional cell site. The device uses its larger antennas to reach distant cell towers, and it provides a strong signal to nearby phones that otherwise would receive a poor signal or no signal.

USB's interior design

Types of Diode

 A diode is a semiconductor device that allows current to flow in one direction while block the current to flow in reverse direction.There are two terminals of diode.one is called cathode while the other is called anode.

The application of diode is very vast.Mostly they are used to rectify waveform but there are also many other functions that a diode performs.

Types of diode:

There are many types of diode which are used to perform separate jobs.The

main types of diode are following.

Zener Diode

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 A zener diode is a diode that provides a stable reference voltage.Unlike simple diode,zener diode runs under reverse bias condition.Once the reverse voltage applied to the zener diode reaches its breakdown voltage,the voltage across the diode remains constant Zener diodes are available with different breakdown voltages so that any voltage can be achieved easily with zener diode.

Zener diode Symbol:

Schottky Diode:

Schottky diode is slightly different from the normal diode because it has low forward voltage drop usually 0.15-0.45 V. Schottky diodes are used where there is a need of limiting losses e.g, in RF applications where there is need of low forward voltage drop.These diodes 

Schottky Diode Symbol:

Light Emitting Diode(LED):

The Light Emitting Diode is one of the most important types of diode.When the diode forward biased and current flows through the junction,it emits light hence the name of the diode.These types of diode are widely used where there is a need of some indication.They are available in different light colors.

Light Emitting Diode Symbol

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Photo-diode:

The photo-diodes are the one which is used to detect light.They are constructed such that they capture energy from photons of light.Photo diodes can also be used to generate electricity.The major example is the solar panels.These are made from photo-diodes to generate electricity from the sunlight.

Photo-diode Symbol

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Varicap or Varactor Diode:

This is the type of diode whose capacitance varies with the function of voltage applies across it.They are operated in reverse bias condition.These types of diode are used as voltage-controllerd capacitors.

Varicap Diode Symbol:

There are many other types but they are not used widely in today's electronics.

7-Segment Display

7-Segment Displays....

A seven segment display is a basic electronic display device that can display digits from 0-9. They find wide application in devices that display numeric information like digital clocks, radio, microwave ovens, electronic meters etc.

The most common configuration has an array of eight LEDs arranged in a special pattern to display these digits. They are laid out as a squared-off figure ‘8’. Every LED is assigned a name from 'a' to 'h' and is identified by its name. Seven LEDs 'a' to 'g' are used to display the numerals while eighth LED 'h' is used to display the dot/decimal.

A seven segment is generally available in ten pin package. While eight pins correspond to the eight LEDs, the remaining two pins (at middle) are common and internally shorted. These segments come in two configurations, namely, Common cathode (CC) and Common anode (CA).

In CC configuration, the negative terminals of all LEDs are connected to the common pins. The common is connected to ground and a particular LED glows when its corresponding pin is given high.

In CA arrangement, the common pin is given a high logic and the LED pins are given low to display a number.

Recorder Pen

hi engineers,!....-> Recorder is this magic pen that converts your written notes into electronic files and then transfers it to your phone and computer via "Bluetooth". I think it’s a great idea and can actually encourage us writers to take to the book and pen more often. I bet authors and illustrators will love it too! My only wish – it auto spell checks the files..... great invention..

World-first experiment achieves direct brain-to-brain communication in human subjects

For the first time, an international team of neuroscientists has transmitted a message from the brain of one person in India to the brains of three people in France.
The team, which includes researchers from Harvard Medical School’s Beth Israel Deaconess Medical Center, the Starlab Barcelona in Spain, and Axilum Robotics in France, has announced today the successful transmission of a brain-to-brain message over a distance of 8,000 kilometres.
"We wanted to find out if one could communicate directly between two people by reading out the brain activity from one person and injecting brain activity into the second person, and do so across great physical distances by leveraging existing communication pathways,” said one of the team, Harvard’s Alvaro Pascual-Leone in a press release. "One such pathway is, of course, the Internet, so our question became, 'Could we develop an experiment that would bypass the talking or typing part of internet and establish direct brain-to-brain communication between subjects located far away from each other in India and France?'"
The team achieved this world-first feat by fitting out one of their participants - known as the emitter - with a device called an electrode-based brain-computer (BCI). This device, which sits over the participant’s head, can interpret the electrical currents in the participant’s brain and translate them into a binary code called Bacon's cipher. This type of code is similar to what computers use, but more compact.
"The emitter now has to enter that binary string into the laptop using her thoughts,” says Francie Diep at Popular Science. "She does this by using her thoughts to move the white circle on-screen to different corners of the screen. (Upper right corner for "1," bottom right corner for "0.") This part of the process takes advantage of technology that several labs have developed, to allow people with paralysis to control computer cursors or robot arms."
Once uploaded, this code is then transmitted via the Internet to another participant - called the receiver - who was also fitted with a device, this time a computer-brain interface (CBI). This device emits electrical pulses, directed by a robotic arm, through the receiver’s head, which make them ‘see’ flashes of light called phosphenes that don’t actually exist.
"As soon as the receivers' machine gets the emitter's binary message over the Internet, the machine gets to work,” says Diep. "It moves its robotic arm around, sending phosphenes to the receivers at different positions on their skulls. Flashes appearing in one position correspond to 1s in the emitter's message, while flashes appearing in another position correspond to 0s.
Exactly how the receivers are recording the flashes so they can translate all those 0s and 1s isn’t clear, but it could be as simple and writing them down with an actual pen and paper.
While it’s not clear at this stage what the applications for this technology could be, it’s a pretty incredible achievement. Oh, and the messages they transmitted? The conveniently brief and friendly, “Hola” and “Ciao”.

The team published its research in the journal PLOS One. http://www.plosone.org/article/authors/info%3Adoi%2F10.1371%2Fjournal.pone.0105225