I'm trying to design a small, hand held, battery powered Arduino device that will receive data from another Adruino device. The data will be presented to the user on a graphical display, maybe about 1.5 inches by 2.5 inches in size. The same hand held device will be used to send simple commands back to the base device. The handheld device needs to run off of something like AA or AAA batteries, but the base device has bigger batteries available. Still, low power consumption is preferred.
I'm having trouble finding an appropriate display panel and trying to decide on a radio type. I know nothing about LCD displays but I do know a little bit about radios.
The radio system will be point to multi-point (base to one or more hand held devices). Handheld devices need not talk to each other and in fact some will just need to receive and display. The payload data probably won't exceed 24 Kb/s (kilo bits per second). The range is small, generally 150 feet or less. I realize I could use FSK devices but my concern is that there could be several of these systems deployed within range of each other and they should not talk with each other. I realize each packet is addressed, but with FSK there could be interference at the RF level. Or maybe not. I'm not really sure. I realize also that Xbee with spread spectrum solves this issue but that is pricy. There is no opportunity to arrange for different channels in advance, and the systems will be mobile and encountering each other with no prior knowledge that this will happen.
The display should be a matrix of dots so software can render any type of display. It should be low power and very readable in direct sunlight. It need not be LCD. It can be color or black and white. The priority is on readability.
So are these requirements just over the top or is this something that could be done with available components? I would appreciate any suggestions. I have not had much luck finding a display, although I am not sure where to look. With the radio, I have the opposite problem; there are many radio choices.