Roy J. Greenfield

Learn More
Ž. We compare the ability of several practical ground-penetrating radar GPR array processing methods to improve Ž. signal-to-noise ratio SNR , increase depth of signal penetration, and suppress out-of-plane arrivals for data with SNR of Ž. Ž. roughly 1. The methods include two-dimensional 2-D monostatic, three-dimensional 3-D monostatic, and 3-D bistatic(More)
The distinguishing spatial properties of low-frequency microphone wind noise (turbulent pressure disturbances) are examined with a planar, 49-element array. Individual, propagating transient pressure disturbances are imaged by wavelet processing to the array data. Within a given frequency range, the wind disturbances are much smaller and less spatially(More)
"Submitted to the Department of Geology and Geophysics on 9 January 1969 in partial fulfillment of the requirement for the degree of Doctor of Philosophy." From dT/dA measurements at LASA, we have derived lower mantle P wave velocities and upper and lower mantle S wave velocities. The P wave data are grouped along two great circle paths from LASA-one(More)
An exact expression is obtained for the acoustic-gravity layer matrix for an atmospheric layer having a linear temperature variation. Expressions are also derived for the layer derivative matrices needed to calculate group velocity and mode excitation. The method requires the evaluation of confluent hypergeometric functions, whose series representations are(More)
  • 1