Remote control

. Welcome to Our Presentation

Course Instructor : RETHWAN FAIZ

.• Group members…………

• ## Hossain,md.riaz ----------------------- 13-24434-2• ##Jesan,Jahidur rahman ------------------- 13-24453-2• ## Puja,ananya dey ----------------------- 13-24322-2• ## Hosssain md rubayet------------------- 13-25385-3• ## Rakin farhan tanvir --------------------- 13-25389-3

Topic…………….

.• There are many types of remote controls on the market

today. Below is a list and description of the most common types of remote controls system.

• Infrared (IR)• Radio Frequency (RF)• Wi-Fi• Combination - IR, RF, Wi-Fi and wired• Remote control type subcategory

INFRARED (IR) …………..

CIRCUIT DIAGRAM

Working process……………….

• Buttons

• Integrated circuit

• Button contacts

• Light-emitting diode (LED)

• You push the "volume up button on your remote control The integrated circuit detects this.

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• The integrated circuit sends the binary "volume up" command to the LED at the front of the remote.

• The LED sends out a series of light pulses that corresponds to the binary "volume up" command..

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• transmit‐side there is just the need for a very simple microcontroller. The number of required input and output pins is basically defined by the number of buttons on the controller.

• The IR‐LED is simply connected to one of the output pins of the microcontroller directly or in some cases driven by an additional transistor stage.

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• As a time‐base a crystal is rather over engineered; most designs rely on a cheap ceramic resonator or even a RC‐oscillator with rather poor frequency stability (up to +/‐5%may be tolerated by the receiver).

• Disposal batteries are the first choice for the power supply.

• As the dimensions of the remote controller case are mainly defined by the number of buttons and ergonomic aspects there is enough space for cheapest AA‐ or AAA‐cells.

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• On the component side, the infrared receiver sits on the front of the device where it can easily see the signal coming from the remote control.

• When the infrared receiver on the TV picks up the signal from the remote and verifies from the address code that it's supposed to carry out this command, it converts the light pulses back into the electrical signal for 001 0010. It then passes this signal to the microprocessor, which goes about increasing the volume. The "stop" command tells the microprocessor it can stop increasing the volume.

.• Its output is already a digital signal with clean edges for easy

protocol handling by a microcontroller. As the data rate on infrared is rather low (approximately 500 to 1000 bit per second) a microcontroller which is anyway in the receiving device may handle the IR‐reception as a side task by simply measuring the time distance between edges using a timer. The real design challenge is the power supply concept since the remote control receiver must remain active even in stand‐by mode of the system.

Radio frequency control…………

. Since most of the

encoders/decoders/microcontrollers are TTL compatible, most of the inputs by the user will be given in TTL logic level. Thus, this TTL input is to be converted into serial data input using an encoder or a microcontroller. This serial data can be directly read using the RF Transmitter, which then performs modulation on it and transmit the data through the antenna.

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• Inside transmitters are wires that allow negatively charged particles, called electrons, to flow through them, which makes an electrical current. When current flows within a wire, it generates an electromagnetic field around the wire. This electromagnetic field radiates out of the antenna in all directions, creating invisible radio waves.

• In the receiver side, the RF Receiver receives the modulated signal through the antenna, performs all kinds of processing, filtering, demodulation, etc and gives out a serial data. This serial data is then converted to a TTL level logic data, which is the same data that the user has input.

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Wi-fi……….

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• A wireless network uses radio waves, just like cell phones, televisions and radios do. In fact, communication across a wireless network is a lot like two-way radio communication. Here's what happens:

• A computer's wireless adapter translates data into a radio signal and transmits it using an antenna.

• A wireless router receives the signal and decodes it. The router sends the information to the Internet using a physical, wired Ethernet connection.

• The process also works in reverse, with the router receiving information from the Internet, translating it into a radio signal and sending it to the computer's wireless adapter.

• The radios used for WiFi communication are very similar to the radios used for walkie-talkies, cell phones and other devices. They can transmit and receive radio waves, and they can convert 1s and 0s into radio waves and convert the radio waves back into 1s and 0s. But WiFi radios have a few notable differences from other radios:

.• They transmit at frequencies of 2.4 GHz or 5 GHz. This frequency is

considerably higher than the frequencies used for cell phones, walkie-talkies and televisions. The higher frequency allows the signal to carry more data.

• They use 802.11 networking standards, which come in several flavors:

• 802.11a transmits at 5 GHz and can move up to 54 megabits of data per second. It also uses orthogonal frequency-division multiplexing (OFDM), a more efficient coding technique that splits that radio signal into several sub-signals before they reach a receiver. This greatly reduces interference.

• 802.11b is the slowest and least expensive standard. For a while, its cost made it popular, but now it's becoming less common as faster standards become less expensive. 802.11b transmits in the 2.4 GHz frequency band of the radio spectrum. It can handle up to 11 megabits of data per second, and it uses complementary code keying (CCK) modulation to improve speeds.

Combination - IR, RF, and wi-fi…..

• Combination Technology remote controls take several of the typical control technologies and combine them into a single remote control. This is usually done for very specific applications. For consumer devices there are 'repeater' systems available that will see an infrared code from a remote control, and then repeat the same signal through the repeater device (through a wall or cabinet) and then convert the signal back into IR to transmit to the device. Some of these repeater devices can also be used with RF remote so that the receiver is located behind a cabinet. In these applications it might be advantageous to have a remote control that will transmit IR signals to line-of-site devices in a room, but also transmit RF signals to devices in another room or located behind a cabinet yet connected to an RF to IR repeater.

REMOTE CONTROL TYPE SUBCATEGORY

• Dedicated Remote Control• Universal Library or Universal Device Remote

Control• Learning Remote Control• Programmable Remote Control

Uses……• Infrared (IR)• Line of sight

• Less Expensive

• Battery life

• Limited Regulatory Requirements

• Common Device

• Radio Frequency (RF)• No line-of-sight required

• Greater Distance

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• Wi-fi

• Using a remote control, or remote-control-like device (such as a smartphone ) with Wi-Fi capabilities allows for connecting to a Wi-Fi network and therefore communicating with any device also connected to the same network. Control can be inside a home or business, or, over the Internet. Communication with another device set up on the network will need to be preprogrammed and the controlled device will also be required to be connected to the same Wi-Fi network.