Looking out for ways to retransmit IR, bi-directionally, like this:
[IR TX-A]----->[IR RTR-1]------>[IR RTR-2]------>[IR RX-B] [IR RX-A]<-----[ ]<------[ ]<------[IR TX-B]
My interest, is in the "IR RTR" device which can retransmit received IR data bidirectionally, s.a. to increase effective distance. While if it is specific to the IR protocol, it is fine, but if it cheaper / easier to behave in a protocol agnostic way, i.e. received signal is just amplified as-is and fed "dumbly" on the transmitter LED, without needing any transmitter, this is quite acceptable, unless of-course it might introduce significant noise, s.t. it becomes difficult / expensive to deal with on the other end.
If there are ready schematics for this, would be glad to be pointed to it.
BTW, I have nothing against a uC based approach, but I'm probably keeping that option as a backup, since my requirements in order of priority are:
- Low cost - My target is a sub $5 BOM -- all components, PCB, battery holder etc. included, but except the enclosure.
- Low power consumption - This is probably going to be the hardest part, given how power-hungry IR LEDs are. Maybe I am dreaming, but it'd be great to see this circuit run-off disposable batteries (like the A23 or PP9), for last for at least 6 months without a change.
- Small size - I'd like to keep it no bigger than a box of Altoids.
Edit: I do not need this to function as a universal remote control range extender, i.e. I am also quite happy if this little device of mine can act as a bidirectional signal repeater for a specific carrier frequency, modulation-type which might well be proprietary and chosen so as to avoid interference and effects of ambient noise.
Edit (#2): Adding some more information about the comm. needs:
- Throughput of 80-100bps is good enough, excluding the error-check/correction overhead
- Communication is bursty but cannot be predicted. However communication during a burst is a repeated transmission of same information several times, s.t. if receiver can sleep/wakeup fast enough, it shouldn't miss information. Information is a 10 byte packet, that is sent upto 10 times, with/without acknowledgement.
- The RX/TX IR-pair in each end-node, and the repeater need to be placed close together to make a compact pair, but I am hoping of avoiding interference between the pair by having some optical barrier between them, similar to double-barrel gun.
- Typical distance between end-node and repeater, I hope to achieve, is 10-12feet.