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MODAL TESTINGAn Introduction to
Frequency Response Functions: frf.pdf

MODAL DENSITYModal Density: mdens.pdf

STATISTICAL ENERGY ANALYSISRadiation
& Driving Point Impedance of a Thin, Isotropic Plate: dp_impedance.pdf

Bruel & Kjaer BookletsStructural Testing 1: Mobility MeasurementStructural Testing 2: Modal
Testing

Software 
Executable 
Source 
Digital filtering using a Butterworth 6th order filter. The user must supply an input time history file. Both lowpass and highpass options are available. 
filter.exe 
filter.cpp 
Fast Fourier transform (FFT) of a time history. The transform operates on a time series with 2^n points, where n is an integer.Also, corresponding inverse FFT. 
fft.exe

fft.cpp

Conventional Fourier transform of a time series with an arbitrary number of points. 
fourier.exe 
fourier.cpp 
Zoom FFT of a time series. 
zoomFFT.exe 
zoomFFT.cpp 
Crossspectrum of two time histories. The output files may be used for modal test data analysis. 
cross_spectrum.exe 
cross_spectrum.cpp 
Crossspectrum of two time histories. The program generates H1 and H2 frequency response functions (FRFs), the coherence function, and the corresponding impulse response functions. 
cross_spectrum_modal.exe 
cross_spectrum_modal.cpp 
This program generates a power transmissibility function for a singledegreeoffreedom subjected to a force input.The transmissibility
dimension is: ( accel^2 / force^2 )

force_trans_modal.exe 
force_trans_modal.cpp 
This program performs a
curvefit on an acceleration spectral function resulting from an
applied force.

bandwidth_damp.exe

bandwidth_damp.cpp

Driving point impedance of a thin plate, bending waves 
dp_impedance.exe 
 
Driving point impedance of a beam, longitudinal waves 
dpi_beam.exe 


Critical and Ring Frequencies of a Cylinder. 
SEA_cylinder_parameters 


Matlab  Script 
Calculate frequency & impulse response functions from an input force and response amplitude time history.  frf_from_th.m Supporting Functions: fix_size.m frf_median_filter.m 
Recommended Books1. D.J. Ewins, Modal Testing: Theory and Practice2. Lyon and Dejong, Theory and Application of Statistical Energy Analysis3. L.
Cremer and M. Heckl, StructureBorne Sound
