The term wireless communication was
introduced in the 19th century and wireless communication technology has
developed over the subsequent years. It is one of the most important
mediums of transmission of information from one device to other devices.
In this technology, the information can be transmitted through the air
without requiring any cable or wires or other electronic conductors, by
using electromagnetic waves like IR, RF, satellite, etc. In the present
days, the wireless communication technology refers to a variety of
wireless communication devices and technologies ranging from smart
phones to computers, tabs, laptops, Bluetooth Technology, printers. This article gives an overview of wireless communication and types of wireless communications.
Types of Wireless Communciation
Introduction To Wireless Communication
In
the present days, wireless communication system has become an essential
part of various types of wireless communication devices, that permits
user to communicate even from remote operated areas. There are many
devices used for wireless communication like mobiles. Cordless
telephones, Zigbee wirelss technology,
GPS, Wi-Fi, satellite television and wireless computer parts. Current
wireless phones include 3 and 4G networks, Bluetooth and Wi-Fi
technologies.
Types of Wireless Communication
The
different types of wireless communication mainly include, IR wireless
communication, satellite communication, broadcast radio, Microwave
radio, Bluetooth, Zigbee etc.
Satellite Communication
Satellite
communication is one type of self contained wireless communication
technology, it is widely spread all over the world to allow users to
stay connected almost anywhere on the earth. When the signal (a beam of
modulated microwave) is sent near the satellite then, satellite
amplifies the signal and sent it back to the antenna receiver which is
located on the surface of the earth. Satellite communication contains
two main components like the space segment and the ground segment.The
ground segment consists of fixed or mobile transmission, reception and
ancillary equipment and the space segment, which mainly is the
satellite itself.
Satellite Communciaiton
Infrared Communication
Infrared wireless communication communicates
information in a device or systems through IR radiation . IR is
electromagnetic energy at a wavelength that is longer than that of red
light. It is used for security control, TV remote control and short
range communications. In the electromagnetic spectrum, IR radiation lies
between microwaves and visible light. So, they can be used as a source
of communication
Infrared Communication
For
a successful infrared communication, a photo LED transmitter and a
photo diode receptor are required. The LED transmitter transmits the IR
signal in the form of non visible light, that is captured and saved by
the photoreceptor. So the information between the source and the target
is transferred in this way. The source and destination can be mobile
phones, TVs, security systems, laptops etc supports wireless
communication.
Broadcast Radio
The
first wireless communication technology is the open radio communication
to seek out widespread use, and it still serves a purpose nowadays.
Handy multichannel radios permit a user to speak over short distances,
whereas citizen’s band and maritime radios offer communication services
for sailors. Ham radio enthusiasts share data and function emergency
communication aids throughout disasters with their powerful broadcasting
gear, and can even communicate digital information over the radio
frequency spectrum.
Broadcast Radio
Mostly
an audio broadcasting service, radio broadcasts sound through the air
as radio waves. Radio uses a transmitter which is used to transmit the
data in the form of radio waves to a receiving antenna(Different Types of Antennas).
To broadcast common programming, stations are associated with the
radio N/W’s. The broadcast happens either in simulcast or syndication or
both. Radio broadcasting may be done via cable FM, the net and
satellites. A broadcast sends information over long distances at up to
two megabits/Sec (AM/FM Radio).
Radio
waves are electromagnetic signals, that are transmitted by an
antenna.These waves have completely different frequency segments, and
you will be ready to obtain an audio signal by changing into a frequency
segment.
Radio
For
example, you can take a radio station. When the RJ says you are
listening to 92.7 BIG FM, what he really means is that signals are being
broadcasted at a frequency of 92.7megahertz, that successively means
the transmitter at the station is periodic at a frequency of 92.700,000
Cycles/second.
When you would like to
listen to 92.7 BIG FM, all you have to do is tune the radio to just
accept that specific frequency and you will receive perfect audio
reception.
Microwave Communication
Microwave wireless communication
is an effective type of communication, mainly this transmission uses
radio waves, and the wavelengths of radio waves are measured in
centimeters. In this communication, the data or information can be
transfers using two methods. One is satellite method and another one is
terrestrial method.
Microwave Communication
Wherein
satellite method, the data can be transmitted though a satellite, that
orbit 22,300 miles above the earth. Stations on the earth send and
receive data signals from the satellite with a frequency ranging from
11GHz-14GHz and with a transmission speed of 1Mbps to 10Mbps. In
terrestrial method, in which two microwave towers with a clear line of
sight between them are used, ensuring no obstacles to disrupt the line
of sight. So it is used often for the purpose of privacy. The frequency
range of the terrestrial system is typically 4GHz-6GHz and with a
transmission speed is usually 1Mbps to 10Mbps.
The main disadvantage of microwave signals is, they can be affected by bad weather, especially rain.
Wi-Fi
Wi-Fi is a low power wireless communication,
that is used by various electronic devices like smart phones, laptops,
etc.In this setup, a router works as a communication hub wirelessly.
These networks allow users to connect only within close proximity to a
router. WiFi is very common in networking applications which affords
portability wirelessly. These networks need to be protected with
passwords for the purpose of security, otherwise it will access by
others
Wi-Fi Communication
Mobile Communication Systems
The
advancement of mobile networks is enumerated by generations. Many
users communicate across a single frequency band through mobile phones.
Cellular and cordless phones are two examples of devices which make use
of wireless signals. Typically, cell phones have a larger range of
networks to provide a coverage.But, Cordless phones have a limited
range. Similar to GPS devices, some phones make use of signals from
satellites to communicate.
Mobile Communication Systems
Bluetooth Technology
The
main function of the Bluetooth technology is that permits you to
connect a various electronic devices wirelessly to a system for the
transferring of data.Cell phones are connected to hands free earphones,
mouse, wireless keyboard. By using Bluetooth device the information from
one device to another device. This technology has various functions and
it is used commonly in the wireless communication market.
Bluetooth Technology
Advantages of Wireless Communication
Any data or information can be transmitted faster and with a high speed
Maintenance and installation is less cost for these networks.
The internet can be accessed from anywhere wirelessly
It is very helpful for workers, doctors working in remote areas as they can be in touch with medical centers.
Disadvantages of Wireless Communication
An unauthorized person can easily capture the wireless signals which spread through the air.
It is very important to secure the wireless network so that the information cannot be misused by unauthorized users
Applications of Wireless Communication
Applications of wireless communication involve security systems, television remote control, Wi-Fi, Cell phones, wireless power transfer, computer interface devices and various wireless communication based projects.
Wireless Communication Based Projects
Wireless communication based projects mainly include different technologies like Bluetooth, GPS, GSM, RFID and Zigbee projects which are listed below.
Wireless Communication Based Projects
Android Based Smart Phone Used for Induction Motor Control
Therefore,
this is all about Types of wireless communication, these networks are
one of the important technologies in the telecommunications market.
WiFi, WiMax, Bluetooth, Femtocell, 3G and 4G are some of the most
important standards of Wireless technology The information which is
given in this article will be helpful to the viewers.Furthermore, any
queries, suggestions or electronics projects,
Radio frequency is an automatic
identification process used for transmitting data between an RFID tag
and RFID reader with the help of radio-frequency electromagnetic fields.
The RFID tag is a device used to store data of any stuff, persons,
books, animals, etc. RFID tags
are of different types some tags can be placed near to the RFID reader
and some can read from far away distances beyond the line of sight of
the reader.
RFID Applications
There are different types of RFID systems
in the market that consists of an antenna, transceiver and a
transponder. These systems operate at different frequency ranges like
low frequency (30-500 kHz), mid frequency (900-1500 kHz) and high
frequency (2.4-2.5GHz). Let us see one of the example based application
of RFID-based-attendance-management system in brief.
RFID Based Attendance System
The
aim of this project is to maintain the record of the students’
attendance by using RFID tags. Each student is issued with his/ her
authorized tag, which can be used for swiping in front of the RFID
reader to record their attendance.
Block Diagram of RFID based Attendance System by Edgefxkits.com
In
most of the colleges and schools,attendance is recorded manually – such
a process consumes lots of time. In this proposed system, attendance
system is implemented by using advanced wireless technology
“RFID”. Only the authorized students are provided with the RFID tags.
This tag consists of an inbuilt integrated circuit for storing and
processing information.
Oscillator circuit is connected between the 18 and 19 th pin of the microcontroller and consist of an oscillator with a frequency of 11.0592 MHz and two capacitors of 33pF.
Preset Circuit
The 9th pin of the microcontroller is RST pin, which is reset pin. This preset circuit comprises a switch, a capacitor of (10u) and a resistor of 10k. When the switch is pressed, the RST pin is connected to the power supply(Vcc) and the microcontroller gets reset.
Circuit Diagram of RFID based Attendance System
LCD Display
The LCD display
is used for displaying the data. It consists of 16 pins: three pins are
connected to the power supply, and the remaining pins are connected to
the port 2 of the microcontroller.
RFID Reader
The RFID reader is a module with RFID reader and antenna. It is small in size and integrates with any sort of hardware design. It is used to read the data stored in the RFID tags.
Circuit Working
The
data stored in this tag is referred to as the identification and
attendance of the person. Once the student places the card in front of
the RFID reader, it reads the data and compares the data stored in the microcontroller which is programmed by using Embedded C language.
If the data matches, then it displays the information on the LCD. This
RFID attendance system also makes use of the status button for
retrieving the status of students’ attendance, which is interfaced to the microcontroller.
By using this advanced concept, a lot of time can be saved as all the
students’ attendance information is directly stored in the database.
Related RFID Applications
In addition to the above discussed project, here we are giving some more applications of RFID system for the reader for understanding purpose.
RFID Technology for Device Control and Authentication in Industries
The
system is designed to provide security in an organization by allowing
only the authorized persons to access the secure area. The main priority
is the security in any organization. The authorized persons are
assigned with RFID tags that allow them into the secured premises.
RFID Technology Based Device Control and Authentication
The RFID tag consists of an integrated circuit, which is used for storing and processing the data, modulating and demodulating
the radio frequency signal that is to be transmitted. When a person
shows the RFID tag in front of the RFID reader and the reader reads the
data and compares the data stored in the system. If the data matches
with the stored data, the system authorizes the person and allows to
enter into the secured area so that the person can take control of
various devices. The system also displays the result on the LCD. If it
finds the provided information mismatched then, it alerts an
unauthorized entry with a buzzer sounds as an indication of entering or providing wrong information.
RFID Technology For Books Tracking in Libraries RFID Technology For Books Tracking in Libraries
Searching
and arrangement of misplaced books is a difficult task often carried
out by the library personnel. Many a times Librarians busily search the
improperly placed books or books wrongly placed by the library users and
students in the library of a school, office or college. And often find
this task very difficult. To overcome this problem, an RFID based
intelligent book tracking system has been developed for monitoring the
books in the library through wireless communication between the RFID
reader and the books. This system consists of RFID tag and RFID reader
to detect the information about the books placed in the library.
RFID Technology for Intelligent Tollgate System
The
proposed system performs the following actions such as detecting,
billing and accounting for vehicles as they pass through a toll gate
within the frequency range between 30 kHz and 2.5GHz. In this system, an
RFID tag is programmed with the vehicle owner’s information in the form
with an EPC (electronic product code) that can ensures to read the data
at certain distances and detects the vehicle in order to enhances a
transaction.
RFID Technology for Authenication of Passport Details RFID Technology for Authenication of Passport Details
A Passport system can become intelligent enough by the implementation of RFID technology
to it. In this system, passport service issues RFID tag to eligible
citizen, which contains passport details like name, address,
nationality, passport number, and other relevant data. During the time
of authentication, the RFID card reader reads that information and
compares it with the data stored in the passport database. If it finds
to be matched, then it will allow for further precedence,otherwise it
alerts the authorities as fake details.
3 Ways to Automatic Plan Irrigation System using Microcontroller
irrigation is defined as artificial application of water to land or soil.
Irrigation process can be used for the cultivation of agricultural
crops during the span of inadequate rainfall and for maintaining
landscapes. An automatic irrigation system does the operation of a
system without requiring manual involvement of persons. Every irrigation
system such as drip, sprinkler and surface gets automated with the help
of electronic appliances and detectors such as computer, timers, sensors and other mechanical devices.
Automatic irrigation system
An
automatic irrigation system does the work quite efficiently and with a
positive impact on the place where it is installed. Once it is installed
in the agricultural field, the water distribution to crops and
nurseries becomes easy and doesn’t require any human support to perform
the operations permanently. Sometimes automatic irrigation can also be
performed by using mechanical appliances such as clay pots or bottle
irrigation system. It’s very hard to implement irrigation systems
because they are very expensive and complex in their design. By taking
some basic points into considerations from experts’ support, we have
implemented some projects on automatic irrigation system by using
different technologies.
In this
article, we are describing about three types of irrigation systems that
work automatically and each system is an advancement of the previous one
as we go from first system to the next, and so on.
1. Automatic Irrigation System on Sensing Soil Moisture Content
Automatic Irrigation System Circuit by www.edgefxkits.com
The
automatic irrigation system on sensing soil moisture project is
intended for the development of an irrigation system that switches
submersible pumps on or off by using relays to perform this action on
sensing the moisture content of the soil. The main advantage of using
this irrigation system is to reduce human interference and ensure proper
irrigation.
The Microcontroller acts
as a major block of the entire project, and a power supply block is
used for supplying power of 5V to the whole circuit with the help of a
transformer, a bridge rectifier circuit and a voltage regulator. The 8051 microcontroller is programmed
in such a way that it receives the input signal from the sensing
material which consists of a comparator to know the varying conditions
of the moisture in the soil. The OP-AMP which is used as comparator acts
as an interface between the sensing material and the microcontroller
for transferring the moisture conditions of the soil, viz.wetness,
dryness, etc.
Block Diagram of Soil Moisture Content Based Irrigation
Once
the microcontroller gets the data from the sensing material – it
compares the data as programmed in a way, which generates output signals
and activates the relays for operating the submersible pump. The
sensing arrangement is done with the help of two stiff metallic rods
that are inserted into the agricultural field at some distance. The
required connections from these metallic rods are interfaced to the
control unit for controlling the operations of the pump according to the
soil moisture content.
This automatic irrigation system can be further enhanced by using advanced technology that consumes solar energy from solar panels.
2. Solar Powered Auto Irrigation System
Solar Powered Auto Irrigation System Circuit by www.edgefxkits.com
In
the above figure, the power from utilities is required to operate the
system. As an extension to the above discussed system, this system uses
solar panels to power the circuit. In agricultural field, the proper
usage of automatic irrigation method is very vital due to some
shortcomings of the real world like scarcity of land reservoir water and
scarcity of rainfall. The water level (the ground water table) is
getting reduced due to continuous extraction of water from the ground
and thus gradually resulting in water scarcity in the agricultural zones
slowly turning them into barren lands.
In
the above irrigation system, solar energy generated from the solar
panels is used for operating the irrigation pump. The circuit comprises
moisture sensors built by using OP-AMP IC. The OP-AMP is used as comparators. Two stiff copper wires are inserted into the soil to know whether soil is wet or dry. A charge controller circuit is used to charge the photovoltaic cells for supplying the solar energy to the whole circuit.
Solar Powered Auto Irrigation System Blockdiagram
A
moisture sensor is used for sensing the soil condition – to know
whether the soil is wet or dry, and the input signals are then sent to
the 8051 microcontroller, which controls the whole circuit. The microcontroller is programmed by using KEIL software. Whenever the soil condition is ‘dry’, the microcontroller sends commands to the relay driver and the motor gets switched on and supplies water to the field. And, if the soil gets wet, the motor gets switched off.
The
signals that are sent from the sensors to the microcontroller through
the output of the comparator operate under the control of a software
program which is stored in the ROM of the microcontroller. The LCD
displays the condition of the pump (on or off) interfaced to the
microcontroller.
This automatic irrigation system can be further enhanced by using GSM technology to gain control over the switching operation of the motor.
3. GSM Based Automatic Irrigation System
Nowadays
farmers are struggling hard in the agricultural fields round the clock.
They do their field work in the morning section and irrigate their land
during night time with intermittent intervals. The task of irrigating
fields is becoming quite difficult for the farmers due to lack of
regularity in their work and negligence on their part because sometimes
they switch on the motor and then forget to switch off, which may lead
to wastage of water. Similarly, they even forget to switch on the
irrigation system, which again leads to damage to the crops. To overcome
this problem, we have implemented a new technique by using GSM technology, which is explained below.
GSM Based Automatic Irrigation System
The
GSM Based automatic irrigation system is a project in which we get
update status of the operation carried out in the agricultural fields
via SMS with the help of a GSM modem. We can also add other systems such
as LCD displays, web cam and other smart controlled devices. In this project, we are using LEDs for indication purpose.
In
this project, we are using soil moisture sensor which is used to sense
the moisture level in the – to know whether it is dry or wet. The
moisture sensor is interfaced with the microcontroller. The input data
signals from the moisture sensor are sent to the microcontroller and
based on that it activates the DC Motor
and switches the motor on with the help of a motor driver. After the
soil gets wet, the Motor gets switched off automatically. The status of
the agricultural fields can be known from the indication of the Light Emitting Diode (LED)
or through the message sent to the GSM modem placed at the field.
Simultaneously it is possible to send messages through a mobile to kit
through the GSM modem. Thus, the irrigation motor can be controlled by
using a mobile and a GSM modem.
