Performance of a cross dipole antenna dedicated to biological telemetry

The needs in biological telemetry relevance grow up for many years. In order to establish a communication in the SRD frequency band (863-870MHz) between a battery-less RFID tag dedicated to be implanted in a mouse and an external reader, the performance of a cross dipole antenna used as emitting antenna is presented in this paper. This evaluation takes into account the mouse body and the cage. To make our test, we also designed a phantom model of the mouse body. Compared to a loop antenna, this solution is less influenced by the phantom presence. Moreover it allows us to cover the critical configuration where the mouse raised on its hind paws (to feed for example) what is not possible with a simple dipole antenna. Measurements of the Received Signal Strength Indication (RSSI) levels have been done to evaluate the performance of this antenna which possesses a measured impedance bandwidth of 8.6%.