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ABSTRACT
The aim of home automation is to control home devices from a central control
point. In this paper, we present the design and implementation of a low cost but yetflexile and secure radio frequency based home automation system. The
communication between the remote and devices is wireless. RF transmission is
robust, reliable and can be used up to 100mtrs. It uses the RF transmitter/receiver
which operates a 434 Mhz and comprises of a pair of encoder/decoder. The
proposed work has been done experimentally and has been verified in real time.
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INTRODUCTION
Automation is todays fact, where more things are being completed every day
automatically, usually the basic tasks of turning on or off certain devices and
beyond, either remotely or in close proximity. The control of the devices when
completely taken over by the machines, the process of monitoring and reporting
becomes more important. There are clearly many benefits to home automation. The
first is greater comfort and convenience especially for old and disabled. A second
is improved safety and security. A third is a high level of control over operating
costs (e.g., energy conservation). The remote control technologies have been used
in the fields like factory automation, space exploration, in places where human
access is difficult. With the development of low cost electronic components home
automation migrated from being an industrial application to home automation. The
home automation, our point of concern deals with the control of home appliances.
In this project we introduced a low cost, flexible, wireless solution to the home
automation. The novel approach in this paper discusses the migration of the initial
control mechanism of devices with simple functionality. The basic aim of this
project is to control the electrical appliances through a remote control using RF
module. This RF module comprises of an RF Transmitter and an RF Receiver. The
transmitter/receiver (Tx/Rx) pair operates at a frequency of 434 MHz. An RF
transmitter receives serial data and transmits it wirelessly through RF through its
antenna. The transmitted data is received by an RF receiver operating at the same
frequency as that of the transmitter. The RF module is used along with a pair of
encoder/decoder. The encoder is used for encoding parallel data for transmission
feed while reception is decoded by a decoder. The Power Unit powers up the entire
circuit, it contains both AC and DC modes of power i.e. if one of them fails then
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the other one can compensate. A step down transformer which steps down 220V
AC to 12V AC.A bridge rectifier for conversion of an alternating current (AC)
input into direct current a (DC) output which provides full-wave rectification from
a two-wire AC input, resulting in lower cost and weight. The 7805 Voltage
regulator is used which stabilize the DC voltages used .The control unit controls all
the appliances and to reduce the cost of the whole system we have eliminated the
microcontroller and instead have used 4x16 Decoders, flip flops, Decimal counters
and transistors.
The most recent survey on smart homes was written by Chan and describes a
general overview of smart home research
1. Market researches claim that most of the homes will be equipped with home
automation systems in the very near future. According to market observers, the
home automation market in India is growing at a compound annual growth rate
(CAGR) of 30 per cent. This growth is mainly driven by the consumer's desire for
an up gradation of their lifestyle. By 2050, approximately 20% of the worlds
population will be at least 60 years old
2. According to the World Health Organization, 650 million people live with
disabilities around the world
3. This paper demonstrates how technology and products that have been developed
for the broad consumer market can provide great benefits for people who have
functional limitations by improving convenience, safety, security, quality of life
and independence.
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HOME AUTOMATION USING RF
Home automation is the use of one or more logic to control basic home functions
and features automatically. It includes the scheduling and automatic operation of
water sprinkling, heating and air conditioning, window coverings, security
systems, lighting, and food preparation appliances. Here, our emphasis is on
lighting using radio frequency. In this RF system the digital data is represented as
variation in amplitude of carrier wave. This modulation technique is known as
Amplitude Shift Keying (ASK). The basic system includes the transmitter and the
receiver. The transmitter contains the remote, power source, encoder IC, RF
transmitter and antenna.
The receiver contains the receiver, decoder, relay and the appliances which have to
be controlled . The complete system deployment diagram is shown in fig. 1.
Complete System Deployment Diagram
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WORKING
In this project we show that how we control electrical appliances with the help of
WIRELESS REMOTE(Radio Frequency Module).
As we press the switch from transmitter end then immediate data is to be
transmitting in the air. Data receive in air by the Radio frequency module and
proceed to the electrical appliances circuit.
In this project we use two circuits one is transmitter and second is receiver.
In the transmitter part we send the rf code by the transmitter by 4 switchs and in
the receiver we use four relay coil for electrical output.
As we want to switch on any electrical appliances we press the switch of the
transmitter.
As the switch is pressed, data is to be transmitting by the radio frequency
module.
In this project we use 433 Mhz modules for data transmission.
We use one encoder ic for data transmission.
All the switches are connected to the encoder. Encoder ic get the data from
the switch and transmit the data in serial by the RF transmitter.
In the receiver circuit we use RF module to get the data and decoded by the
decoder. Decoder deliver the data into 4 bit and we use further control circuit to
switch on/off.
This circuit utilizes theRF module(Tx/Rx) for making a wireless remote,
which could be used to drive an output from a distant place.
RF module, as the name suggests, uses radio frequency to send signals.
These signals are transmitted at a particular frequency and a baud rate.
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A receiver can receive these signals only if it is configured for that
frequency.
RECEIVER
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TRANSMITTER
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The input signals, at the transmitter side, are taken through four switcheswhile the outputs are monitored on a set of fourLEDscorresponding to each
input switch.
The outputs from the receiver can drive correspondingrelays connected to
any household appliance.
This radio frequency (RF) transmission system employs Amplitude Shift
Keying (ASK) with transmitter/receiver (Tx/Rx) pair operating at 434 MHz.
The transmitter module takes serial input and transmits these signals through
RF.
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The transmitted signals are received by the receiver module placed away
from the source of transmission.
The system allows one way communication between two nodes, namely,
transmission and reception.
In every card we use one encoder ic with digital data base, this digital data
base may be 16 bit or 32 bit. In this project we use 4 bit data base to show
the basic concept of this project Easily available encoder and decoders are
HT12 E and HT 12D. HT12 E is encoder ic and HT 12D is decoder ic We
use 18 pin version of encoder and decoder ic.
TheRF modulehas been used in conjunction with a set of four channel
encoder/decoder ICs. HereHT12E&HT12Dhave been used as encoder and
decoder respectively.
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COMPONENT ANALYSIS
Encoder (HT12E IC)
HT12E is an encoder integrated circuit of 212 series of encoders. They are paired
with 212 series of decoders for use in remote control system applications. It is
mainly used in interfacing RF circuits.
Application Diagram of HT12E encoder
The parallel signals generated at transmission end are first encoded (into serial
format) by HT12E and then transferred through RF transmitter (434 MHz) at a
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baud rate of around 1-10 kbps. It has a transmission enable pin which is active low
and begins a 4-word transmission cycle upon receipt of a transmission enable. This
cycle is repeated as long as TE is kept low. As soon as TE returns to high, the
encoder output completes its final cycle and then stops. It uses a low power and
high noise immunity CMOS technology whose operating voltage is 2.4~12 V. The
value of resistance R2 is 470 Kohm.
CONTROL UNIT
The control unit controls generates binary code by using transistors. It converts 16
decimal inputs into 4 bit binary data which is fed into the encoder IC.
TRANSMITTER & ANTENNA
The RF transmitter is an electronic device which, usually with the aid of an
antenna, propagates an electromagnetic signal
such as radio. The transmitter and receiver are tuned at same frequency. Data rates
are more than 10k bps and the output power up to 10dBm [6]. It performs a low
voltage operation down to 2.2V. It is shown in fig.4.
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The antenna transmits the signal in the ultra-high frequency range which is
received by the antenna of the receiver.
TRANSFORMER
A transformer is a static electromagnetic device that transfers an electrical
power from one circuit to another without change of frequency. It accomplishes
this by electromagnetic induction and where the circuits are in mutual inductive
influence of each other. A transformer consists of a core and two or more windings
coupled electromagnetically. There are primary windings and secondary
windings. The winding in which in which energy is delivered is known as the
primary winding while the winding to which energy is received is known as the
secondary winding. It is shown below.
An Ideal Transformer
WORKING PRINCIPLE OF A TRANSFORMER
A transformer works on the principle of mutual induction between two or
more inductively coupled coil .It consists of primary and secondary windings.When the primary winding is energized by sinusoidal voltage, an alternating
current flows in the primary winding. The alternating current so produced in the
primary winding set up an alternating magnetic flux in the core .The alternating
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flux link up the secondary winding thereby inducing e.m.f in the secondary
winding.
The type of transformer used in this project is a step-down transformer,
which steps the voltage from 220v to 12v.
BATTERY
An electric batteryis a device consisting of one or moreelectrochemical cells that
convert stored chemicalenergy into electrical energy. Each cell contains a positive
terminal, orcathode,and a negative terminal, oranode.Electrolytes allow ions to
move between the electrodes and terminals, which allows current to flow out of the
battery to perform work.
Primary (single-use or "disposable") batteries are used once and discarded; the
electrode materials are irreversibly changed during discharge. Common examples
are the alkaline battery used forflashlights and a multitude of portable
devices.Secondary (rechargeable batteries) can be discharged and recharged
multiple times; the original composition of the electrodes can be restored by
reverse current. Examples include the lead-acid batteries used in vehicles and
lithium ion batteries used for portable electronics. Batteries come in many shapes
and sizes, from miniature cells used to powerhearing aids and wristwatches to
battery banks the size of rooms that provide standby power fortelephone
exchanges and computerdata centers.
http://en.wikipedia.org/wiki/Electrochemical_cellhttp://en.wikipedia.org/wiki/Energyhttp://en.wikipedia.org/wiki/Cathodehttp://en.wikipedia.org/wiki/Anodehttp://en.wikipedia.org/wiki/Electrolytehttp://en.wikipedia.org/wiki/Primary_batteryhttp://en.wikipedia.org/wiki/Flashlighthttp://en.wikipedia.org/wiki/Secondary_batteryhttp://en.wikipedia.org/wiki/Rechargeable_batterieshttp://en.wikipedia.org/wiki/Hearing_aidhttp://en.wikipedia.org/wiki/Telephone_exchangehttp://en.wikipedia.org/wiki/Telephone_exchangehttp://en.wikipedia.org/wiki/Data_centerhttp://en.wikipedia.org/wiki/Data_centerhttp://en.wikipedia.org/wiki/Data_centerhttp://en.wikipedia.org/wiki/Telephone_exchangehttp://en.wikipedia.org/wiki/Telephone_exchangehttp://en.wikipedia.org/wiki/Hearing_aidhttp://en.wikipedia.org/wiki/Rechargeable_batterieshttp://en.wikipedia.org/wiki/Secondary_batteryhttp://en.wikipedia.org/wiki/Flashlighthttp://en.wikipedia.org/wiki/Primary_batteryhttp://en.wikipedia.org/wiki/Electrolytehttp://en.wikipedia.org/wiki/Anodehttp://en.wikipedia.org/wiki/Cathodehttp://en.wikipedia.org/wiki/Energyhttp://en.wikipedia.org/wiki/Electrochemical_cell8/12/2019 Abs Trac 2234
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WORKING PRINCIPLE OF A BATTERY
Batteries convert chemical energy directly to electrical energy. A battery consists
of some number of voltaic cells. Each cell consists of twohalf-cells connected inseries by a conductive electrolyte containing anions and cations. One half-cell
includes electrolyte and the negative electrode, the electrode to
whichanions (negatively charged ions) migrate; the other half-cell includes
electrolyte and the positive electrode electrode to whichcations (positively charged
ions) migrate.Redox reactions power the battery. Cations are reduced (electrons
are added) at the cathode during charging, while anions are oxidized (electrons are
removed) at the anode during discharge. The electrodes do not touch each other,
but are electrically connected by theelectrolyte. Some cells use different
electrolytes for each half-cell. A separator allows ions to flow between half-cells,
but prevents mixing of the electrolytes.
Each half-cell has an electromotive force (or emf), determined by its ability to
drive electric current from the interior to the exterior of the cell. The net emf of the
cell is the difference between the emfs of its half-cells. Thus, if the electrodes have
emfs and , then the net emf is ; in other words, the net emf is the
difference between thereduction potentials of thehalf-reactions.
The electrical driving force or across theterminals of a cell is known as
the terminal voltage (difference)and is measured involts.The terminal voltage of
a cell that is neither charging nor discharging is called theopen-circuit voltage and
equals the emf of the cell. Because of internal resistance,[14]the terminal voltage of
a cell that is discharging is smaller in magnitude than the open-circuit voltage and
the terminal voltage of a cell that is charging exceeds the open-circuit voltage. An
ideal cell has negligible internal resistance, so it would maintain a constant
terminal voltage of until exhausted, then dropping to zero. If such a cell
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maintained 1.5 volts and stored a charge of onecoulomb then on complete
discharge it would perform 1.5joules of work. In actual cells, the internal
resistance increases under discharge and the open circuit voltage also decreases
under discharge. If the voltage and resistance are plotted against time, the resulting
graphs typically are a curve; the shape of the curve varies according to the
chemistry and internal arrangement employed.
Symbol of battery
RECEIVER
The Receiver Box will be fitted into the normal switch board of the room and we
can configure the line connections as fully automated or semi-automated. The
Receiver Box will get the signals from the remote control. It will then decode the
serial signal into 4 bit binary data. The binary data will be then converted into
equivalent decimal form. With the help of this decimal system we can operate up
to 24 or 16 electrical appliances in a room. The addressing can also be done on the
decoder chip to increase the number of rooms to 256. The Receiver Box also has
an uninterruptible power system so that incase power fails the conditions of the
respective appliances remains same i.e. the appliances which were ON remains ON
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and the appliances which were OFF remains OFF. The RF receiver is shown in
fig.. and its application diagram is shown in fig.9.
Fig.. RF Receiver
DECODER (HT12D IC)
HT12D Decoder is used to decode the RF Signal. They are 212 decoders are a
series of CMOS LSIs for remote control system. application which are paired with
212 series of encoder. For proper operation, a pair of encoder/decoder with the
same number of addresses and data format should be chosen. The Operatingvoltage is 2.4V~12V.
They interpret the first N bits of code period as addresses and the last 12-N bits as
data, where N is the address code number. A signal on the DIN pin activates the
oscillator which in turn decodes the incoming address and data. The decoders will
then check the received address three times continuously. If the received address
codes all match the contents of the decoders local address, the 12-N bits of data
are decoded to activate the output pins and the VT pin is set high to indicate a valid
transmission. This will last unless the address code is incorrect or no signal is
received.The output of the VT pin is high only when the transmission is valid.
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Otherwise it is always low. The application diagram is shown in fig.. The value of
resistance R3 is 33 Kohm.
CONTROL UNIT
It uses 4x16 Decoders, flip flops, Decimal counters and transistors [9]. The 24 pin
7474 IC is used as a 4X16 Decoder. It utilizes TTL circuitry to decode four binary-coded inputs into one of sixteen mutually exclusive outputs when both the strobe
inputs, G1 and G2, are low. The demultiplexing function is performed by using the
4 input lines to address the output line, passing data from one of the strobe inputs
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with the other strobe input low. When either strobe input is high, all outputs are
high. Its connection Diagram is shown in fig..
Toggle switch d flip flop using CD 4013 is used to toggle a relay or other load with
a momentary push button. Several push buttons can be wired in parallel to control
the relay from multiple locations. The only time a significant current flows - is
while the output pins are in the process of changing state. The outputs are -
"complementary". When the transistor switches on - it connects the negative side
of the relay coil to ground. And this causes the relay to energize. The transistor
does a second job. It connects the negative side of the LED (light emitting diode)
to ground which acts as an indicator. .
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RELAYS
The appliances are connected to the relay unit. It isolates AC from DC and also
provides switching of AC from DC.
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ADVANTAGES
ADVANTAGES
Ease of operability to the owner
Low cost
High level of security
Savings of the energy bills
Less consumption of time
Save life during fire
Highly efficient and flexible
Reliable
Provide comfort to elderly and disabled
All in one user-friendly system
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APPLICATIONS
Burglar Alarm, Smoke Alarm, Fire Alarm, Car Alarm, Security System
Garage Door and Car Door Controllers
Cordless telephone
Other Remote Control System
Wireless security systems
Car Alarm systems
Remote controls.
Sensor reporting
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CONCLUSION & FUTURE SCOPE
An automated home is convenient and cost-efficient. It saves time and money as it
is pre-programmed to automatically do daily routine events. By combining all the
types of work which are being done individually by home automation, the work
becomes more flexible in order that all the work is done at once. In this paper we
introduced a low cost, flexible, wireless solution to the home automation. The
novel approach in this paper discusses the migration of the initial control
mechanism of devices with simple functionality using radio frequency.Home
automation has wide scope in the future.
Future homes will be able to offer almost all required services
e.g., communication, medical, energy, utility, entertainment, and security. With
microprocessor control however, home climate control systems can be
programmed to meet precise preferences related to the time of day or the day of the
week. Today, home automation is no longer a futuristic fantasy and just confined
to the affluent class but a reality that is being associated with mainstream design as
well and is slowly becoming a part of everyday life. Home owners from different
social strata have begun seriously contemplating the adoption of technology to
ensure comfort, convenience and personal security. According to market observers,
the home automation market in India is growing at a compound annual growth rate
(CAGR) of 30 per cent. This growth is mainly driven by the consumer's desire for
an up gradation of their lifestyle.
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REFERENCES
[1] M. Chan, D. Est`eve, C. Escriba, and E. Campo, A review of smart homes -
Present state and future challenges,Comput. Methods Programs Biomed. , vol. 91,
pp. 5581, Jul. 2008.
[2] (2008, Dec. 1).Available: http://www.un.org/News/Press/
docs//2007/pop952.doc.htm 2012.
[3] (2009, Jun. 23) http://www.who.int/disabilities/en/
[4] Simon Haykin, Digital Communications, Wiley, 1988
[5] Gao Wenhuan, Liu Runsheng, Basic knowledge of Electric Circuit. Higher
Education Press. Beijing, 1996.
[6] Melly, T.; Porret, A.-S.; Enz, C.C.; Vittoz, E.A., An ultralow-power UHF
transceiver integrated in a standard digital CMOS process: transmitter, Solid-State
Circuit, IEEE Journal, vol.36, no.3, pp.467-472, Mar 2001
[7] W. Yao and Y. E. Wang "Ultra-wide band pulse transmitting through resonant
antennas",Int. J. Opt. Wireless Commun., 2006
[8] C. W. Solomon "Switched-capacitor filters: precise, compact, inexpensive",
IEEE Spectrum, vol. 25, pp.28 1988
[9] Adel S. Sedra, Kenneth C. Smith, Arun N. Chardorkai Microelectronics
circuits theory and applications, fifth edition.
[10] B.G. Streetman and S. Banerjee, Solid state electronics devices, 5th Edition,
PHI.