This system uses RF transmission technology. The RF transceiver module which I use has a range up to 100 metres in ideal conditions. This module can transmit and receive 4-bit parallel data with or without 8 address bits using a specific encoder and decoder ICâ„¢s. Another module can be designed such that it can transmit and receive 8-bit parallel data with or without 10 address bits using a specific encoder and decoder ICâ„¢s. The advantage of having the address bits is that message transfer can be made secure.
8-bit parallel data implies that 256 combinations of 0â„¢s and 1â„¢s can be transmitted and received. By using a keypad a specific parallel data of 0â„¢s and 1â„¢s can be generated. This can be transmitted and received through RF module and can be decoded to the same parallel 8-bit data. Now by using a PIC I can interface a LCD module and display the message on it. I will also use a LCD module in the transmitter module and display the message on it. Thus a message transferring system can be established.
Here the communication link can be one to one or one to many.
One to many communication link can be achieved by not addressing any of the address bits in the transmitter and in the receiver module. Thus if we transmit in this way all the receiver modules in the range will receive the message.
One to one communication link can be achieved by generating a specific address code. The transmitted message can be received only if the receiver module also has the same address. For this we need to have a protocol. We can also have the receiver sets already addressed to specific address and a message will be received by it if the transmitter module also has the same address.
Can be used as a messaging system between the students and management if each student has a specific address or else it will be received by everyone if the sets are not addressed.
Can be used as a communication link b/w people living in apartments.
Any two individuals can use it if they address their transceivers in their unique code.
Many more applications can be found as communication link is essential for all.
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