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pro vyhledávání: '"Homer P. Bucker"'
Autor:
Homer P. Bucker
Publikováno v:
The Journal of the Acoustical Society of America. 59:368-373
The calculated complex sound field cj for sensor j at depth zj and range rj from a sound source of frequency ω and depth z0 can be written in the normal‐mode form as cj= (2π/rj)1/2 ΣmUm(z0) Um(zj) exp[i (kmrj−ωt)]. Here, km is the horizontal
Autor:
Homer P. Bucker
Publikováno v:
The Journal of the Acoustical Society of America. 62:1222-1225
In cross‐sensor beamforming the narrow‐band quadrature signal at one sensor is multiplied by the complex conjugate of the narrow‐band quadrature signal at a second sensor to form a stable element of the cross‐sensor field. After suitable time
Autor:
Homer P. Bucker
Publikováno v:
The Journal of the Acoustical Society of America. 61:756-762
Samples of the quadrature field {Fj} collected on a uniform linear array can be quickly analyzed to determine the bearings of targets by use of the FFT or Prony algorithm. These methods are compared for many realizations of a realistic ocean acoustic
Autor:
Homer P. Bucker
Publikováno v:
The Journal of the Acoustical Society of America. 63:420-424
The methods of high‐resolution spectral analysis can be used for high‐resolution cross‐sensor beamforming for a uniform line array. In this paper two high‐resolution techniques (maximum entropy and discrete decomposition) are applied to the c
Autor:
Homer P. Bucker
Publikováno v:
The Journal of the Acoustical Society of America. 73:486-491
The split‐step algorithm is the standard method for calculating complex (i.e., amplitude and phase) sound fields in a range dependent ocean environment. However, in ocean areas with strong bottom interaction, density discontinuities, sediment rigid
Autor:
Homer P. Bucker
Publikováno v:
The Journal of the Acoustical Society of America. 61:494-498
By using the cross‐sensor field, a beam pattern (for a one‐wave, no‐noise acoustic field) can be generated for a sparse array which is the same as for a filled array. When real‐world effects, such as noise and multiwave acoustic fields, are c
Autor:
Homer P. Bucker
Publikováno v:
The Journal of the Acoustical Society of America. 68:1123-1126
This paper examines cross‐sensor processing for a U‐shaped array and for a horizontal line array. Attention is given to accounting for crossterms in the cross‐sensor field (cross‐spectral matrix) caused by doublet (i.e., two multi‐paths) ar
Autor:
Homer P. Bucker
Publikováno v:
The Journal of the Acoustical Society of America. 68:1768-1772
Scattering integrals are derived that represent the contribution of boundary scattering in a sound channel. These integrals are added to the normal mode sum which represents the coherent field in the channel. A comparison is made between experimental
Autor:
Homer P. Bucker
Publikováno v:
The Journal of the Acoustical Society of America. 65:906-908
Sound propagation in a uniform duct can be represented as a sum of normal modes plus a branch line integral(s) contribution. In the case of a homogeneous liquid layer lying over a homogeneous liquid half‐space the complex modes exhibit a complicate
Autor:
Homer P. Bucker
Publikováno v:
The Journal of the Acoustical Society of America. 65:145-147
The cross‐sensor field of an array consists of all products of the narrow‐band quadrature signal measured at one sensor multiplied by the complex conjugate of the quadrature signal measured at a second sensor. Three algorithms which use the cross