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The objective of CASPER is to improve our capability to characterize the propagation of radio frequency (RF) signals through the marine atmosphere with coordinated efforts in data collection, data analyses, and modeling of the air–sea interaction processes, refractive environment, and RF propagation.

The development of new geoacoustic inversion methods, their use in the analysis of shallow water experimental data, and evaluation of geoacoustic model and parameter uncertainties including the mapping of these uncertainties through to system performance uncertainties.

The development of new geoacoustic inversion methods, their use in the analysis of shallow water experimental data, and evaluation of geoacoustic model and parameter uncertainties including the mapping of these uncertainties through to system performance uncertainties. Analysis of geoacoustic inversion data collected from various experiments. Of specific technical interest are: (1) development of methods to track the environmental parameters using sequential filtering, (2) use of ambient noise for estimation of seafloor structure parameters, and (3) the development of new inversion methods for use into the kHz frequency regime. In an ONR Graduate Traineeship Awards we address using Random Matrix Theory in ocean acoustics.

Utilize signals from emitters of opportunity to (a) evaluate sources of propagation predictions (e.g., numerical weather prediction), and (b) provide real-time refractivity information using EM inverse methods.

Long-term Goals: Fuse refractivity inferred from electromagnetic (EM) propagation observations with background fields from numerical weather prediction (NWP) models. Objectives: Develop data fusion method for atmospheric refractivity scheme based on objective analysis. Develop means to map observations of refractivity based on RF propagation measurements into the space utilized for the analysis. Exercise the data fusion scheme on a combination of synthetic and real data to assess performance. Achieve reasonable processing time (on the order of 1-minute) with a representative domain size using a high-end laptop computer., Prepared in collaboration with University of California, San Diego, CA.

The development of new geoacoustic inversion methods, their use in the analysis of shallow water experimental data, and evaluation of geoacoustic model and parameter uncertainties including the mapping of these uncertainties through to system performance uncertainties. Analysis of geoacoustic inversion data collected from various experiments. Of specific technical interest are: (1) development of methods to track the environmental parameters using sequential filtering, (2) use of ambient noise for estimation of seafloor structure parameters, and (3) the development of new inversion methods for use into the kHz frequency regime. In an ONR Graduate Traineeship Awards we address using Random Matrix Theory in ocean acoustics., The original document contains color images.

The development of new geoacoustic inversion methods, their use in the analysis of shallow water experimental data, and evaluation of geoacoustic model and parameter uncertainties including the mapping of these uncertainties through to system performance uncertainties. Analysis of geoacoustic inversion data collected from various experiments. Of specific technical interest are: (1) development of methods to track the environmental parameters using sequential filtering, (2) use of ambient noise for estimation of seafloor structure parameters, and (3) the development of new inversion methods for use into the kHz frequency regime.

Develop electromagnetic propagation models, and refractivity inversion algorithms, that perform equally well over land and sea and in the presence of anomalous propagation conditions for both surface and airborne emitters, for use in operational or engineering propagation assessment systems.

Develop electromagnetic propagation models, and refractivity inversion algorithms, that perform equally well over land and sea and in the presence of anomalous propagation conditions for both surface and airborne emitters, for use in operational or engineering propagation assessment systems. Develop an advanced unified hybrid radio propagation model based on parabolic equation and rayoptics methods for both surface-based and airborne applications. This model is named the Advanced Propagation Model (APM) and is the primary model used in the Advanced Refractive Effects Prediction System (AREPS). The specific technical objectives are to develop algorithms to extract surface clutter only from weather files provided by the Hazardous Weather Detection and Display Capability (HWDDC); and to improve, refine, and optimize the current state-of-the-art Refractivity From Clutter (RFC) algorithms to infer and characterize surface-based ducts (SBD)., Prepared in collaboration with Scripps Institute of Oceanography, San Diego, CA.