Android for Beginners – What is it and what types of connectivity are there?
When we read the technical specifications of a smartphone that we have or that we are buying,
we always see a section called Connectivity. In it we see strange things sometimes WiFi,
Bluetooth, and many numbers that is difficult to understand. In today’s article of Android for
Beginners , I will try to explain what each of those words and figures.
According to the RAE, connectivity is “the ability to connect or make connections.” Therefore,
everything we read about it, is designed to sync, connect to or communicate with any other
device, is another smartphone, printer, modem or whatever you can think of.
Bluetooth
It is a form of connection between the radio frequency by ISM band 2.4 GHz devices. As a result
we can transmit voice and data. Communication protocol is designed for low-power devices, and
do not need a large range and low cost transceivers. Therefore, it is difficult to beyond 25
meters are able to communicate with Bluetooth (from your smartphone). We disposing of repeaters
may be able to get to a hundred meters.
Depending on the channel capacity, that is, its bandwidth, is classified into versions. The
last and latest version is 4.1, over 24 Mbit / s (about 2.92 MB). The power required to
transmit a maximum of 10 meters is 1 mW, while for longer ranges necessary between 100mW and 1
W (mW is milliwatt).
Wi-Fi
Another mechanism connecting devices wirelessly is the WiFi. They may, through him, to connect
to the Internet through a wireless access point network. Wi-Fi is a trademark of the Wi-Fi
Alliance, which is the trade organization that tests and certifies that terminals comply with
the 802.11 standard.
But what does it mean that we see 802.11 specifications? Such a little to rough and easily, are
the “rules of operation” of a WLAN (wireless local area network). When we see, for example,
802.11a / b / g, mean that meets certain protocols. It would be long and complicated to
explain, so that you can ented, I will say that these protocols define the band in which they
operate, the speed of data transmission, and the number of channels .
In principle, for the public, the more protocols accepts your terminal or your modem, ie, the
more letters after the 802.11 better.
3G and LTE
With 3G talk about the third generation voice and data over UMTS mobile telephony. With this
generation, we could also transfer non-voice data, ie, programs, and other mailings.
The greatest evolution, besides speed, was security. With 3G, the European Union can
authenticate the network to which you are connected, ensuring the user that the network is good
and not an imitation. Now it is much more difficult to access information from others with 3G.
3G evolution was the LTE, with much better spectral efficiency, a latency (delays within a
network) and very low adaptive band-width. The maximum speed at which it can operate is 326.5
Mbps downlink and 86.5 Mbps upstream. In addition, much improves your ability to move devices
and can operate at speeds up to 500km / h. Those who have risen AVE will know how bad it is
when you go 3G in motion.
NFC
Something that goes into fashion just because Apple includes in the new iPhones, but Android is
something that we have long.
Isabel wrote long ago about what is NFC and what it does, so I invite you to read his article.
Also If you do not know how to send things from one phone to another, we have written a
tutorial for transferring files with NFC , so do not miss it.
USB
“Universal Serial Bus“, better known as USB. It is the industry standard that defines the
cables, connectors and used to connect and communicate PC, phones and electronic devices in
general protocols.
When the USB is created, you could transfer files to 188 kB / s, this is the USB 1.0, and is
still used mainly for keyboards and mice. USB 2.0 can transfer at a maximum speed of 60 MB /
sec, but in fact, in practice, only reaches 35 MB / sec. The second generation USB cable
consists of two pairs of wires into one for power supply, and one for the data transfer. USB
3.0 can transfer up to 600 MB / sec theoretically.