Search

Results from our experiments on inertial navigation in crash testing of vehicles are presented. A custom designed inertial measurement unit (IMU) has been developed, and several tests in dummy calibration rigs including full-scale Euro NCAP collisions have been performed at our partners' crash test laboratories. For reference, the IMU data is compared to camera data and traditional single-axis inertial sensors.

We experimentally demonstrate the performance of the recently proposed "OBP" algorithm based on optical phase retrieval by numerical back-propagation. Using this technique, distortion due to the modulator transfer function as well as the group velocity dispersion in a photonic time-stretch ADC (TS-ADC) can be suppressed, and frequency fading eliminated thanks to the use of a dual output "phase diverse" modulator. The algorithm was tested with a swept input signal frequency from 10 to 50 GHz. as well as with a two-tone signal, and is shown to recover the signal even in the presence of fading with a distortion suppression of up to 26 dB. These results also constitute the first experimental demonstration of channel combining in a phase diverse TS-ADC.

A novel interferometric scheme for photonic analog-to-digital conversion (ADC) is experimentally demonstrated at a real-time sample rate of 40 gigasamples/s. The input signal in the experiment was a 1.25 GHz sinusoidal tone and the resolution 21 digital levels with an effective number of bits (ENOB) of 3.6. The major benefits of this scheme are that only one standard phase modulator is required and that the phase swing does not have to be larger than ±π to reach the full digital value space.