Remote Controlled Home Automation Using Bluetooth

The main aim of this project is to control the electrical appliances in home like lights, fans, motors, etc using Bluetooth module.

These Bluetooth modules are more reliable, secure and low power modules and these modules do not require line of sight also. We can use mobile Bluetooth by developing some applications or we can use normal USB blue tooth dongles by connecting to PC.

Bluetooth is a wireless technology standard for exchanging data over short distances (using short-wavelength radio transmissions in the ISM band from 2400–2480 MHz) from fixed and mobile devices, creating personal area networks (PANs) with high levels of security. Created by telecom vendor Ericsson in 1994, it was originally conceived as a wireless alternative to RS-232 data cables. It can connect several devices, overcoming problems of synchronization.

Bluetooth uses a radio technology called frequency-hopping spread spectrum, which chops up the data being sent and transmits chunks of it on up to 79 bands (1 MHz each; centered from 2402 to 2480 MHz)  in the range 2,400–2,483.5 MHz (allowing for guard bands). This range is in the globally unlicensed Industrial, Scientific and Medical (ISM) 2.4 GHz short-range radio frequency band. It usually performs 800 hops per second, with Adaptive Frequency-Hopping (AFH) enabled.

At controlling system side we have Bluetooth module, micro controller and load controlling circuits. Whenever this blue tooth module receives command from its paired blue tooth transmitter then it transfers this command to micro controller. Micro controller will control the respective loads depends upon the command it received


Bluetooth module

Software Tools:

  • KEIL IDE for developing micro controller code
  • ORCAD for designing schematics
  • PROLOAD or FLASH MAGIC for dumping the hex file into controller


Hardware Tools:

  • AT89S52 Micro controller.
  • MOC3021 for driving TRIACs.
  • BT136 for controlling AC loads.
  • Blue tooth module
  • Ø Regulated +5v Power supply.


  • No need of separate remote or switch boards for controlling electrical appliances
  • Protection from shock while operating
  • Ø Easy to use, children, old aged people, physically challenged people can also operate


  • Office automation
  • Home automation
  • Machines controlling system in industry
  • Door access control system