The NLFM waveform resulting from a tunable integrated optical ring resonator is simulated and compared with the well
known tan-FM waveform. The metrics of interest are the first sidelobe levels and FWHM times of the autocorrelation,
as these directly relate to the long-range performance and fine range resolution of a LADAR system, and should ideally
be as small as possible. Through simulation, the sidelobe level of the autocorrelation of an NLFM waveform generated
by a series of tunable integrated optical ring resonators is shown to be lower than the autocorrelation sidelobe level of an
equivalent optimized tan-FM waveform with an equal FWHM time. A proof of concept experiment employing
thermally tunable Silicon Nitride integrated optical ring resonator is shown to generate NLFM chirped waveforms with
frequency chirps of 28 kHz.
The aim of this work was to demonstrate the fabrication and characterization of erbium-doped optical waveguide
amplifiers in X-cut Y-propagating lithium niobate (LiNbO<sub>3</sub>) by erbium (Er) and titanium (Ti) co-diffusion. Optical
small-signal internal gains up to +0.6 dB/cm at 1531 nm were measured for the transverse electric (TE) and magnetic
(TM) modes by optical pumping at 1488 nm with a coupled optical pump power of 95 mW in four different optical
waveguide amplifier lengths. The Er and Ti co-diffusion process has shown adequate internal gain efficiency in dB/mW
and a beneficial path for the development of LiNbO<sub>3</sub>-based integrated optical devices.
This paper reports on recent advances made in real-time intruder detection for an intrusion system utilizing a phasesensitive
optical time-domain reflectometer developed at Texas A&M University. The system uses light pulses from a
highly coherent laser to interrogate an optical fiber. The Rayleigh backscattered light is detected, and real-time
processing of the received signal is implemented using an FPGA-based system. Signatures from a single human on foot
and automobile have been obtained, and are comparable to results obtained with previous signal processing techniques.
Individual footsteps are clearly identified for the single human intruder. With the introduction of real-time signal
processing, the system can be run continuously, only triggering intrusions when they are detected. These recent
advancements allow us to process intruder signatures more effectively. With these advancements, this technology is a
prime candidate for low-cost perimeter monitoring of high-value and high-security targets such as nuclear power plants,
military bases, and national borders.