  Recent ground- and space-based observations reveal the presence of
small-scale motions between convection cells in the solar photosphere. In these
regions small-scale magnetic flux tubes are generated due to the interaction of
granulation motion and background magnetic field. This paper studies the
effects of these motions, on magnetohydrodynamic wave excitation from broadband
photospheric drivers. Numerical experiments of linear magnetohydrodynamic wave
propagation in a magnetic flux tube embedded in a realistic gravitationally
stratified solar atmosphere between the photosphere and the low choromosphere
(above $\beta=1$) are performed. Horizontal and vertical velocity field drivers
mimic granular buffeting and solar global oscillations. A uniform torsional
driver as well as Archimedean and logarithmic spiral drivers mimic observed
torsional motions in the solar photosphere. The results are analysed using a
novel method for extracting the parallel, perpendicular and azimuthal
components of the perturbations, which caters for both the linear and
non-linear case. Employing this method yields the identification of the wave
modes excited in the numerical simulations and enables a comparison of excited
modes via velocity perturbations and wave energy flux. The wave energy flux
distribution is calculated, to enable the quantification of the relative
strengths of excited modes. The torsional drivers excite primarily Alfv\'en
modes (~60% of the total flux) with small contributions from the slow kink
mode, and, for the logarithmic spiral driver, small amounts of slow sausage
mode. The horizontal and vertical drivers excite primarily slow kink or fast
sausage modes respectively, with small variations dependent upon flux surface
radius.
