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Since aortic pressure cannot be measured noninvasively, pressure signals are often measured at more superficial arteries and a transfer function is applied to obtain a surrogate for the central pressure curve. These transformations are usually derived from measurements in a specific group of subjects and a generalised transfer function is calculated thereof. In contrast, in this work a one-dimensional wave propagation model is used to derive a patient-specific transfer function. A model of the arterial tree is combined with the theory from Womersley for blood flow in elastic vessels. This approach allows an explicit solution of the wave equations. Thus the pressure at each location in the arterial tree can be calculated from a stationary component and forward and backward travelling waves. To obtain a transfer function, it is sufficient to derive the transfer function from one arterial segment to its parent vessel by relating forward and backward travelling waves via the reflection coefficient of the corresponding bifurcation. An extension to further segments can then be achieved by multiplication of the associated functions. This leads to an analytical transfer function which incorporates all model parameters and enables a patient-specific choice of these parameters reflecting arterial properties (eg. arterial lengths, radii, stiffness). The transfer function based on an arterial tree model and wave propagation theory can be personalised by optimising model parameters to fit a specific patient. This may provide more accurate estimates of central pressure curves and thus could enhance the precision of pulse wave analysis and its clinical value.