PHUNG , Duy-Ha

Distributed feedback (DFB) diode lasers are convenient, small footprint and robust single mode laser sources. Control of the diode forward current allows for the control the frequency of the emitted laser beam. Locking the laser frequency to some optical frequency discriminator, such as an optical interferometer or an atomic or molecular line,...

We have achieved DFB laser diode line narrowing by simultaneously acting on the diode current via a feedback loop and on an external electrooptic phase modulator in feed-forward actuator. This configuration turns out to be very efficient in reaching large bandwidth in the phase correction: up to 15 MHz with commercial laser control units. About...

Downlink measurement campaigns from the optical downlink terminal OSIRISv1 onboard the LEO satellite Flying Laptop were carried out with the French Observatoire de la Côte d'Azur and with two Optical Ground Stations of the German Aerospace Center. On/off keyed data at 39 Mb/s were modulated on the laser signal, and according telecom reception...

The Grasse Satellite Laser Ranging (SLR) station (ID7845), part of the International Laser Ranging Service (ILRS) network, participates to various laser applications including SLR, Lunar Laser Ranging (LLR), Time Transfer by Laser Link (T2L2), high-resolution imagery, and debris detection. Since 2014, in collaboration with the France Space...

For satellite to ground laser links, atmospheric turbulence is a major cause of impairments. The induced phase perturbations along the propagation path cause beam scintillation in the receiver plane and they can also severely compromise the coupling of the flux into a receiver of limited size. To address these impairments, dedicated mitigation...