Nordic Semi: Wireless sports timing solution provides accurate high-speed data

Mobii Systems, a Cape Town, South Africa-based sports technology company, has selected Nordic Semiconductor’s nRF52840 advanced multiprotocol System-on-Chip (SoC) to provide processing power, data storage, low power 2.4GHz communication, and over-the-air device firmware update (OTA-DFU) capability for the ‘Active Transponder’ and ‘Active Pod’ devices within its ‘Mobii Timing’ ecosystem of sports timing solutions.

The Active Transponder uses a solar cell and energy harvester to charge its small Li-Poly battery.

In operation, the Active Transponder is attached to the arm or leg of a race participant, or on to equipment such as a bicycle or boat. Active Pods placed at various fixed locations along the route of a race (including the start and/or finish line) can then wirelessly read and record the high-speed timing data triggered by the Active Transponders as each participant passes each reader. The Active Pod employs two Nordic nRF52840 SoCs to synchronize and interrogate the Active Transponders passing close by. One SoC behaves as a primary transmitter to ‘wake up’ and synchronize the Active Transponders; the other SoC receives the data from the Active Transponder.