Patent ID: 7026939

Claim:
A system for acquiring data from a subject animal, the system comprising: at least one passive data acquisition device associable with a subject animal, the at least one device comprising: at least one sensor operable to provide sensor data relating to the subject animal; a radio frequency identification (RFID) transponder operable to transmit an RFID telegram comprising the sensor data, wherein the RFID telegram comprises: an ISO 11785-formatted full duplex identification telegram, the sensor data outside the ISO 11785-formatted full duplex identification telegram; and wherein a first portion of the ISO 11785-formatted full duplex telegram is contained in a portion of the RFID telegram intended for transmit during an initial ISO 11785 activation period, and a second portion of the ISO 11785-formatted full duplex telegram is contained in a portion of the RFID telegram intended for transmit during an extended ISO 11785 activation period; and at least one magnet separate from the transponder; and a transceiver, the transceiver operable: to activate the at least one passive data acquisition device, and to receive and demodulate the REID telegram from the data acquisition device sent in response to the activation; the transceiver comprising: an activation antenna configured to encompass areas of substantially equal and substantially opposite flux; and a receive antenna configured symmetrically along an axis of symmetry of the activation antenna.