A new type of all-single-mode fiber depolarizer, based upon a 2 x 2 coupler and a recirculating delay line and useable with a coherent light source, is proposed and demonstrated. The reduction in the degree of polarization is examined theoretically and experimentally. Design criteria and principles are discussed. With a narrow-band laser source, the degree of polarization was tuned between 99.8...

2 the delay between two amplified pulses by delaying one of the replicas. The repetition rate of the oscillator is around 80 MHz, which means every seed pulse is inherently separated by around 12 ns. As a result, we can introduce a time delay between two replica pulses of up to 12 ns. Here, we utilize an optical delay line covering this 12 ns delay range with better than 30 fs resolution. The d...

In this paper, we discuss a simplified finite element method (FEM) simulation of surface acoustic wave (SAW) delay line hydrogen sensor using COMSOL Multiphysics. A delay line SAW sensor consists of a transmitting interdigital transducer (IDT) and a receiving IDT separated by a few wavelengths. In this paper, the number of degrees of freedom (DOF) to solve for the SAW delay line sensor model is...

We design and experimentally demonstrate 50 picoseconds (ps) low loss delay line on 300 nm SOI platform. The delay line unit consists of straight rib waveguide and strip bend section linked by a transition taper waveguide. Low propagation loss of ~0.1 dB/cm is achieved on the straight rib waveguide. With taking into account both low loss and desirable delay, a complete design and characterizati...

We describe the use of a matched linearly chirped fiber Bragg grating (FBG) pair as a key element in an adjustable optical delay line. This delay line has the unique property that the achievable optical group delay is orders of magnitude greater (factor of 10(2) in our experiment) than the actual physical displacement. We demonstrate operation of such an optical delay line over a delay range of...

This is the final report on the project entitled “Validation of AMSR snow depth on sea ice retrievals using an airborne pulse radar.” This is a collaborative project between the Center for Remote Sensing of Ice sheets (CReSIS) at the University of Kansas and NASA Goddard Space Flight Center (GSFC). We designed and developed ultrawideband radars for measuring thickness of snow over sea ice from ...

flop, a diode logic unit with current-steering amplifier, a passive delay line, and an active variable delay circuit, all of which are designed to operate with terminated 75-ohm transmission lines. Ten-nanosecond pulses and 20-nanosecond flip-flop transition times are achieved through use of very-high-speed MADT transistors. The circuits have been successfully employed in the FX-l, a small gene...