Chip timing

A transponder working on a radio-frequency identification (RFID) basis is attached to the athlete and emits a unique code that is detected by radio receivers located at the strategic points in an event.

RFID was first used in the late 1980s primarily for motor racing and became more widely adopted in athletic events in the mid-1990s upon the release of low cost 134 kHz transponders and readers from Texas Instruments.

This technology formed the basis of electronic sports timing for the world's largest running events as well as for cycling, triathlon and skiing.

Active transponder systems continued to mature and despite their much higher cost they retained market share in the high speed sports like motor racing, cycling and ice skating.

Awards in a race are generally based on the "gun time" (which ignores any delay at the start) as per IAAF and USA Track and Field rules.

In both cases, care must be taken to ensure the UHF tag does not directly touch a large part of the skin as this affects read performance.

Because these UHF tags are made in huge volumes for industrial applications, their price is much lower than that of conventional re-usable transponders and the race does not bother to collect them afterwards.

[2] All RFID timing systems incorporate a box housing the reader(s) with peripherals like a microprocessor, serial or Ethernet communications and power source (battery).

In the case of low or medium frequencies these consist of wire loops incorporated into mats that cover the entire width of the timing point.

The software relates the raw transponder code and timestamp data to each entrant in a database and calculates gun and net times of runners, or the splits of a triathlete.