Mobile object e.g. foot ball, position determining device for use in playing field, has mechanism obtaining phase information of modulation signal, where transmission and modulation signals are received by three antennas

摘要

The device has a radio transmitter (102) for sending a transmission signal (104-1, 104-2) from carrier and modulation signals, where the signal (104-1) is characteristic for a moving object e.g. foot ball. A mechanism obtains phase information of the modulation signal, where the transmission and modulation signals are received by three antennas. Another mechanism determines position of the transmitter based on the phase information, where frequency of the carrier signal lies in the range from 2.2 to 2.6 giga hertz. Frequency of the modulation signal lies in the range from 1 to 3 giga hertz. Independent claims are also included for the following: (1) a system comprising three antennas (2) a method for determining a position of an object (3) a computer program comprising instructions to perform a method for determining a position of an object.