The LIDAR Echo Emulator (LEE) emulates the returned signals from a Lidar system. As the return signal of a Lidar system depends on the target, this implies the capability of shaping the lasers returns. In brief, long echo corresponds to a natural or diffusive object (canopy, clouds) and short echoes to a hard object like roofs, ground, etc. Such signals are necessary to be simulated to study and validate new detectors and detection systems without developing/procuring entire Lidar system. LEE consists of pulse shaping electronics to drive independently the lasers for each echo and internal detection system to monitor the pulses. The short echoes can be in the range from 5 ns to hundreds of ns and the long echoes from 1 µs up to hundreds of µs. The repetition rates of the developed emulator are from 100 Hz to 10 kHz with limitation that the longest pulse does not exceed 10% of the duty cycle. The power difference between both echoes can be set and is as high as 60 dB. The dynamics of the echoes is better than 50 dB within the 8 ns in the rising/falling edge of the pulse (echo). The output power can be tuned by means of variable attenuators giving a range of the incoming echoes from -35 dBm to -100 dBm. The LEE can also emulate multiple returns with aforementioned dynamics.
A radiation hard image sensor HAS2 was chosen for the Juice Monitoring Camera, an important instrument to monitor the status of the JUpiter ICy moons Explorer (JUICE) spacecraft and to take wide-angle images of the Jovian system. To improve the perception, a radiation-hardened, non-organic color filter array (CFA) was deposited on the sensor silicon, with four colors: red, green, blue, and yellow. In this paper we present the results of the radiation tests on these customized image sensors. First, results on the total ionizing dose (TID) test up to 57 krad confirm that both the image sensor and the deposited CFA are resistant to gamma radiation in the measured range. Also, single event effects (SEE) measurements up to LET of 100 MeV•cm 2 /mg were performed. Three types of events were considered: single event latch-up (SEL), single event upset (SEU), and finally single event functional interruption (SEFI). Since only one SEL was registered on one of the samples at 62.5 MeV•cm 2 /mg there was no further analysis on this event. Based on the experimental results, the cross sections have been calculated for SEU and SEFI. These results were used as input for the SEE analysis with the CRÈME96 software. The rates of about 10 -4 and 10 -5 events/device/day were obtained for SEU and SEFI for quiet environment, respectively.
12 Mpix color commercial-of-the-shelf (COTS) image sensor from CMOSIS was tested with proton radiation. The target mission required an irradiation with protons of energy of 50 MeV and fluences up to 1·10 12 p/cm 2 . Several intermediate steps were introduced to check the behavior of the image sensor. A low-cost test camera was developed to control the image sensors, acquire the images, and monitor the currents and voltages during the tests. Each color was characterized separately according to the EMVA 1288 standard. Such treatment allowed also analysis of the bayer filter deposited on the image sensor surface. Post-radiation characterization revealed that a significant deterioration in the parameter performance was found independently of the pixel color. The most affected parameters were dark current and dark signal nonuniformities (DSNU) which have increased from about one to two orders of magnitude.
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