U_Stormcrow
Crossing the Road
I believe @aart has the right of this, for reasons others have chimed in with.
Just spit-balling it, you've got four options, with three sets of problems (one of which is sort of shared by all).
GPS with transmitter is too big, too heavy, and requires constant charging as its an active amplifier and transmitter. Reducing it to a single chip, like you see on a cell phone, broadcasting say once every five minutes, and pairing with an LI-style micro cell phone battery you could use an induction charger as your roosting bar. Limited accuracy but potentially great range.
Bluetooth same problems as GPS, except that it doesn't provide location data - but you don't need fancy equipment to read the signal, though with a large flock of birds, that's a lot of pairing to try until you discover the ID of the missing bird. Its also non directional.
Active RFID - much like Bluetooth, though range has improved dramatically with 3rd gen, you would need a specialized scanner, but its semi-directional and most of the battery bower can be concentrated there, in a hand held unit.
Passive RFID - this has no range, but no battery needs. Current technology, I understand, allows some of these to be read as much as 30' away. Cover your property in stakes with tiny solar panels, like path lights with rechargeable AA batteries, and you can cover a theoretically infinite area. Or connect them up with landscape wiring, tie in some electronics, and make a distributed network to feed location on every RFID back periodically to a laptop, etc.
Battery assisted passive designs greatly improve range, allowing greater spacing of posts, but the more frequently you ping, the faster the battery runs down.
So. Possible. Not Practical.
Just spit-balling it, you've got four options, with three sets of problems (one of which is sort of shared by all).
GPS with transmitter is too big, too heavy, and requires constant charging as its an active amplifier and transmitter. Reducing it to a single chip, like you see on a cell phone, broadcasting say once every five minutes, and pairing with an LI-style micro cell phone battery you could use an induction charger as your roosting bar. Limited accuracy but potentially great range.
Bluetooth same problems as GPS, except that it doesn't provide location data - but you don't need fancy equipment to read the signal, though with a large flock of birds, that's a lot of pairing to try until you discover the ID of the missing bird. Its also non directional.
Active RFID - much like Bluetooth, though range has improved dramatically with 3rd gen, you would need a specialized scanner, but its semi-directional and most of the battery bower can be concentrated there, in a hand held unit.
Passive RFID - this has no range, but no battery needs. Current technology, I understand, allows some of these to be read as much as 30' away. Cover your property in stakes with tiny solar panels, like path lights with rechargeable AA batteries, and you can cover a theoretically infinite area. Or connect them up with landscape wiring, tie in some electronics, and make a distributed network to feed location on every RFID back periodically to a laptop, etc.
Battery assisted passive designs greatly improve range, allowing greater spacing of posts, but the more frequently you ping, the faster the battery runs down.
So. Possible. Not Practical.
, but these below are a lot cheaper than the professional types (
