Fig 1

LOS deformation of one GB-rad"

Fig 2

New measurement geometry"

Fig 3

Variation curve of GDOP with ${{\boldsymbol{\alpha}} _{\bf{1}}}$ when ${{\boldsymbol{\beta }}_{\bf{3}}}{\bf{ = }}{\bf{90}}^{\bf{\circ}} $ "

Fig 4

Variation curve of GDOP with ${{\boldsymbol{\beta}} _{\bf{3}}}$ when ${{\boldsymbol{\alpha}} _{\bf{1}}} = {\bf{45}}^{\bf{\circ}} $ "

Fig 5

Variation map of the GDOP with ${{\boldsymbol{\alpha}} _{\bf{3}}}$ and ${{\boldsymbol{\beta}} _{\bf{3}}}$ when ${{\boldsymbol{\alpha}} _{\bf{1}}} ={\bf{ 30}}^{\bf{\circ}} $ "

Fig 6

Variation curves of the GDOP when ${{\boldsymbol{\alpha}} _{\bf{1}}} = {\bf{30}}^{\bf{\circ}} $ "

Fig 7

Variation map of the GDOP with ${{\boldsymbol{\alpha}} _{\bf{3}}}$ and ${{\boldsymbol{\beta}} _{\bf{3}}}$ "

Fig 8

Variation curves of the GDOP when ${{\boldsymbol{\alpha}} _{\bf{1}}} {\bf{=}} {\bf{60}}^{\bf{\circ}} $ "

Fig 9

Simulated geometry to resolve 3-D deformation of a slope S "

Table 1

Simulation parameters m "

Fig 10

GDOP map under the optimal geometry"

Fig 11

Variation curve of $ {\overline {\boldsymbol{G}} _{\bf{S}}} $ with ${{\boldsymbol{R}}_{{\boldsymbol{1x}}}}$ "

Fig 12

Variation map of $ {\overline {\boldsymbol{G}} _{\boldsymbol{S}}} $ with ${{\boldsymbol{R}}_{\bf{3}}}$ "