Ultra-compact bird-borne s-band transceiver aiming to search low pathogenic avian influenza

We produced an ultra-compact bird-borne transceiver unit (weight of circuit board(5g) excluding solar battery and rechargeable battery system, harness of the crate) for S-band packet radio communications based on the CC2500 transceiver, a device manufactured by Texas Instruments (TI). We performed assessments to determine optimal parameters required to achieve successful bird-to-center communication over a distance of 18 km and bird-to-bird communication over a distance of 200 m, including optimal modulation method, transmission rates, and antenna. We equipped the transceiver unit with a modified dipole antenna (collinear antenna), which we tested in a 10-m anechoic chamber. Our experimental assessments and circuit design review pointed to the following parameters: 2FSK modulation method; 14.28 kHz frequency shift; 101.56 kHz IF reception bandwidth; and Manchester encoding(+). Our assessments showed bird-to-bird communications could be achieved over a distance of 200 m assuming MSK, FEC(+), and 500 kbps.