Transmitter/Receiver Project. Close Proximity

[magic]

I'm not an electrical engineer and need some help with a small project in which four transmitters send four different signals to a small recepter across a distance of maybe 15 or 20 feet. The transmitters need to be quite small, or at least thin, maybe 3/8''s of an inch thick and no more than 3/4'' by 3/4''. The receiver can be much bigger, but prefereably no bigger than an old cellphone. 

Essentially I need to know when the transmitters are moved (it doesn't need to be super sensitive, but such that when each transmitter is lifted, it signals the receiver) and the signal for each transmitter must be different (such as the receiver fibrating once, twice, thrice or four times depending on which transmitter is moved). Given this set up, I imagine the transmitters can be activated (sorry for my naivite,  that's probably not the right word) using an infrared system, motion sensitive system, or maybe most simply, a magnetic system (i.e, when the transmitter is moved from a magnetic plate, it transmits a signal to the receiver).

Any thoughts on where I might procure the necessary materials for such a project, and how to set it up?

Thank you very much for the help.

Feel free to email [email protected], if you have advice.

[Prabakaran P M]

Try zigbee for your transmission and reception of data,and accelerometer for the sensing of moves.

 

[Marco Guerreiro]

There is the PIR sensor, which is a motion sensor. But not sure if it is applicable to your project. 
If the transmitter will be small, maybe you can use a LDR, which is a resistor that varies with light. It may be faced down, so whenever it is lifted, there will be light and the resistance will varie. But that would not work at night.. 

For transmitting the signal, Zigbee it is an option, but not a very cheap one. Maybe you could use the small 433MHz modules. Is the use of a microcontroller possible?

 

[magic]

Thanks for the advice everyone, I greatly appreciate it. Per your question, what would the microcontroller be used for? Aside from a a concern over space where the transmitter is, I don't see why it couldn't be used.

[Marco Guerreiro]

I thought of using a microcontroller to distinguish from signal from different transmitters, and to send commands such as "go into sleep mode".. but I am not sure how necessary it really is 

[Author]

Posts