System for position determination or distance measurement by time-of-flight measurement, the system comprising at least one interrogation unit and at least one transponder, the interrogation unit transmi tti ng an i nterrogati on signal by means of radio, sound or light to the transponder, which is responded to by the transponder with a response signal likewise by means of radio, sound or light, which in turn is received by the interrogation unit, whereby the time between interrogation and response is determined and the distance between interrogation unit and transponder is calculated therefrom, the transponder comprises a detector for detecting the interrogation signal, the i nterrogati on unit comprises a detector for detecti ng the response signal, characterized in that 1 the interrogation unit first generates or creates the interrogations internally by means of a precise or quartz clock in a fixed time grid, whereby individual interrogations may also be omitted in this grid, 2 the interrogation unit has at least one variable delay element (VDLY1) for the interrogations thus generated, which makes it possible to shift the interrogation signal, which initially obeys the time grid, variably (VarDly) in time in the grid and then to transmit it, 3 the transponder delays the interrogations then received and detected by the detector in at least one clocked register chain (DFF1-DFF4), consisting of at least one clocked digital or analog register - the optional designs D-flip-flop, sample/hold, charge-coupled device - CCD - and analog/digital converter - ADC - included - and triggers the response with the signal thus delayed, 4 this register chai n in the transponder is clocked by a precise or quartz clock generator from a local register clock, which is in fixed frequency relation to the time grid of the interrogation unit, but does not have to be phase synchronous, 5 with the aid of the variable delay element (VDLY1) in the i nterrogati on unit, that point in time is determined on the part of a controller of the interrogation unit by means of a stepwise changed setting of the delay (VarDly) at which an immediate takeover in the register chain takes place exactly at a clock edge of the register clock just by means of a clock signal in the transponder, whereas a time jump of at least one further register clock peri od of the received response signal occurs in the case of a slight additional delay, 6 to that setting of the delay, which causes an immediate takeover of the query in the register chain exactly at aclock edge of the register clock, at least a high-precision measurement of the signal propagati on time is made. 1 the interrogation unit first generates or creates the interrogations internally by means of a precise or quartz clock in a fixed time grid, whereby individual interrogations may also be omitted in this grid, 2 the interrogation unit has at least one variable delay element (VDLY1) for the interrogations thus generated, which makes it possible to shift the interrogation signal, which initially obeys the time grid, variably (VarDly) in time in the grid and then to transmit it, 3 the transponder delays the interrogations then received and detected by the detector in at least one clocked register chain (DFF1-DFF4), consisting of at least one clocked digital or analog register - the optional designs D-flip-flop, sample/hold, charge-coupled device - CCD - and analog/digital converter - ADC - included - and triggers the response with the signal thus delayed, 4 this register chai n in the transponder is clocked by a precise or quartz clock generator from a local register clock, which is in fixed frequency relation to the time grid of the interrogation unit, but does not have to be phase synchronous, 5 with the aid of the variable delay element (VDLY1) in the i nterrogati on unit, that point in time is determined on the part of a controller of the interrogation unit by means of a stepwise changed setting of the delay (VarDly) at which an immediate takeover in the register chain takes place exactly at a clock edge of the register clock just by means of a clock signal in the transponder, whereas a time jump of at least one further register clock peri od of the received response signal occurs in the case of a slight additional delay, 6 to that setting of the delay, which causes an immediate takeover of the query in the register chain exactly at aclock edge of the register clock, at least a high-precision measurement of the signal propagati on time is made.