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A simulator (Wa-LiD) was developed to simulate the reflection of LiDAR waveforms from water across visible wavelengths. The specific features of the simulator include 1) a geometrical representation of the water surface properties; 2) the use of laws of radiative transfer in water adjusted for wavelength and the water's physical properties; and 3) modeling(More)
A new approach based on a mixture of Gaussian and quadrilateral functions was developed to process bathymetric lidar waveforms. The approach was tested on two simulated data sets obtained from the existing Water-LIDAR (Wa-LID) waveform simulator. The first simulated data set corresponds to a sensor configuration modeled after a possible future satellite(More)
Self-complementary two-arm equiangular spiral antennas were fabricated on silicon-on-sapphire substrates. Picosecond photoconductive pulse generation and sampling were used to investigate their transient radiation properties. Results are presented on transient response, bandwidth, polarization, and radiation pattern. The equiangular spiral antenna is found(More)
A brief tutorial on the picosecond photoconductive effect is given. The use of picosecond optoelectronics for the characterization of broadband antennas is described. In particular, the transient radiation properties of equiangular-spiral and exponentially tapered coplanar-strip antennas are discussed. The transient radiation behavior and the polarization(More)
The complex transmission functions (amplitude and phase) of frequency selective surfaces were measured using optoelectrically generated broadband microwave transients. The amplitude and phase of the transmission function of an array of cross dipoles with a=462 mu m, b=214 mu m, and g=1770 mu m are shown. The corresponding results of a sample with a=927 mu(More)
Waveform measurements at the internal nodes of a 0.5- mu m CMOS SRAM (static random-access memory), performed at room temperature and at low temperature (80 K), are presented. These measurements yield detailed information on the internal operation of the circuit, and, more precisely, on the delays whose sum constitutes the access time in this high-speed(More)
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