Batteryless Speed and Timestamp Recorder with Multi-channel FM Radio Featuring Bicycle Frame Antenna

A batteryless bicycle speed recorder has been developed that has a robust timestamp function using a multi-channel FM broadcast receiver. A robust media search technique that searches audio data stored in the recorder corresponding with a time tagged database of a broadcaster guarantees the precise time. For robust time identification, a gamma-matched bicycle frame antenna is proposed that improves the signal-to-noise and distortion ratio (SINAD) of the received audio signal and detects FM broadcast signals at multiple channels. We fabricated a batteryless speed recorder with a two-channel FM receiver and verified its effectiveness in bicycle road tests.