Measurement of the optical to electrical detection delay in the detector for ground-to-space laser time transfer

Abstract

We present a new type of measurement and the first results of determination of the optical to electrical delay of a photon counting detector. This type of measurement has not been reported for photon counting. The absolute value of the time interval between the time of arrival of the signal photon onto the detector input aperture and the time when the electrical output signal exceeds the pre-defined level must be determined. The optical to electrical delay value is required for ground-to-space laser time transfer with picosecond accuracy. The laser time transfer link is under construction for the European Space Agency for its application in the experiment Atomic Clock Ensemble in Space. We have developed the measurement technique and have measured the detection delay of the solid state photon counter. The experiment is described along with the first results.

Identification and calibration of ground system biases in ground to space laser time transfer

“…• D3, D5 detection delays of the photo detectors may be determined by a new procedure proposed and tested in our laboratory with the accuracy of each contributor of 15 ps [5].…”

“…The absolute value of an optical to electrical delay D5' of a detector was determined using a procedure described in [5]. The optical test pulses 80 ps long at a wavelength of 531 nm were generated by a laser PicoQuant LDH-P-FA-530B.…”

Photodiode optical to electrical signal delay

“…In the previous experiment [3] we found a solution where only one PD was used and its delay was compensated. Therefore the contributor of the optical to electrical delay on linear photodiode was not necessary to evaluate.…”

“…Up to now, the photon counting detector parameters of interest were timing resolution, stability and related parameters only. That is why a new measurement technique had to be developed and tested [3]. Individual contributors of delays was identified and evaluated.…”

Time Transfer by Laser Link — T2L2: Current status and future experiments

“…-δ PPS ; δ f coming from propagation in cables and measured by the calibration station -δ ocx ; δ ocf coming from propagation in free space and determined form the geometrical distance -δ det coming from propagation inside the detector (optical-electrical) and deduced form a propagation model (currently studied) [ 9 ]. The table 2 is an example of what we get for the MeO station OCA has two laser stations (fixed: MeO and mobile: FTLRS) that can be used together in order to realize a time transfer in a co-location configuration (Fig.…”