The stations continuously digitise the low-frequency signals from the antennas in the range from 3000 to 30000 Hz with a sampling rate of over 500 kHz. In this frequency range, the flashes generate particularly clear signal deflections, which lead to
atmospheric interference in radio traffic and can generally also be perceived as crackling noises with a conventional AM radio in long and medium wave broadcasting.At the same time, a
GPS signal is received and analysed. This is used to determine the exact location of the respective receiving station and at the same time provides a highly precise, common time base. The Blitzortung method is based on the
time of arrival (ToA) principle. If a lightning signal is detected, it is sent to a central server for evaluation. If at least three lightning signals from different stations arrive at the server within a short time window, the server can determine the distance to the respective receiver from the arrival times of the signals. Figuratively speaking, the server draws a
hyperbola line around two of the receivers, which can be calculated from the propagation time of the signals around each station. The signal from the third receiver is used as a time reference for the calculation. The point of impact is where the hyperbolas intersect. This method is generally referred to in surveying technology as
multilateration, whereby the
hyperlocation used here represents a special case of this, in which the points of equal time difference lie on hyperbola lines in the plane. Usually, significantly more than three receivers are involved, which improves the accuracy. Due to the long range of the signals, which occur at altitudes of a few kilometres - up to 100 kilometres in the case of so-called
sprites - a large coverage can be achieved with a relatively thin station network. The closer the stations are to the impact site and the more stations pick up the signal, the more precise and accurate the resulting location. == Media reception ==