A generalized Doppler power spectrum for wireless environments

We provide a direct derivation of a generalized Doppler power spectrum of t he signal received by a mobile station traveling at a constant velocity. Th e derivation uses the three-dimensional (3-D) incident radiation intensity and the receiving antenna pattern to obtain an;expression for the generaliz ed power spectrum which is useful in environments where the 3-D propagation characteristics of wireless signals must be taken into consideration. A sp ecial case of radiation confined to a plane is considered to obtain the pow er spectrum givenin the book written by Jakes.