A Frequency-Programmable Miniaturized Radio Frequency Transmitter for Animal Tracking

Abstract

In animal tracking applications, smaller transmitters can reduce the impact of the transmitter on the tagged animal and thus provide more accurate data about animal behavior. By combining a novel circuit design and a newly developed micro-battery, we developed frequency-programmable and more powerful radio frequency transmitters that are about 40% smaller and lighter in weight than the smallest commercial counterpart for animal monitoring at the time of development. The new radio frequency transmitter has a miniaturized form factor for studying small animals. Designs of two coding schemes were developed: one transmits unmodulated signals (weight: 152 mg; dimensions: Ø 2.95 mm × 11.22 mm), and the other transmits modulated signals (weight: 160 mg; dimensions: Ø 2.95 mm × 11.85 mm). To accommodate different transmitter life requirements, each design can be configured to transmit in high or low signal strength. Prototypes of these transmitters were evaluated in the laboratory and exhibited comparable or longer service life and higher signal strength compared to their smallest commercial counterparts.

The Secret Lives of Miniature Batteries

“…Miniature primary batteries are used in a variety of wildlife tracking tags. Some articles on tracking tags discuss the challenging characteristics of such tags and how to adapt to them [4][5][6]9].…”

“…Miniature batteries, both primary and rechargeable, remain the dominant power source for implantable, ingestible, and injectable biotelemetry devices [1,2], asset tracking tags [3], wildlife tracking tags [4][5][6], and miniature electronic devices in many other applications. Miniature batteries are far from ideal voltage sources.…”