Compact, Highly Mobile Wireless Optical Communications
Developed in collaboration with the MDAS.ai laboratory at the University of Michigan-Dearborn, this device was designed to provide handheld wireless data communication capabilities to the user without relying on traditional RF channels. The mainboard includes both cool-white and infrared LEDs which can be keyed on and off independently at rates greater than 100 kHz, wirelessly transmitting encoded data over short distances invisibly. Fully assembled, with the mainboard and edgeboard soldered at a 90-degree angle, the unit measures approximately 22.5mm long by 16.5mm wide by 14mm tall.
Powered by STM32
Responsible for data acquisition, digital encoding, and transmitter LED driving, an STM32L4 microcontroller constitutes the central nervous system of this compact transmitter. An internal RC oscillator, capable of supporting main clock speeds of up to 80 MHz, conserves real estate by removing the need for an external crystal oscillator, and a multiple-channel DMA controller means that data can be acquired simultaneously with encoding and transmission with very little overhead. The board’s four-lead ribbon cable connector supports data acquisition over I2C.
Designed for 2 x AA Operation
All integrated circuits have been carefully selected to ensure a wide voltage operating range such that two AA batteries can power the entire system, whether alkaline or single-use lithium. The ribbon cable I2C interface also includes power and ground connections, allowing the unit to power whatever external I2C data acquisition device is attached.