Radar Datacube

Radar Datacube -> multi-dimensional array containing data at receiever

The datacube is a method of organizing the data collected by the
receiver(s). There are different ways of constructing the cube based
on the radar system.

Fast v. Slow Time

One dimension of the radar datacube is fast-time. Each cell in the
datacube along this dimension represents the data collected at that
sample. The number of samples in this dimension correspond to the
number of samples collected between each pulse. The first sample is
the data collected as the pulse is transmitted. The last sample is the
data collected before the pulse is transmitted.

In time-domain, the plot of one PRI of fast time data will be a
sinusoid signal.An FFT of this data, range-fft, can determine the
range of a scatterer, with a FMCW radar using stretch-processing.

The slow time dimension indexes the fast time data by pulse. Each set
of fast time data samples corresponds with a pulse, or chirp in a
continuous wave radar. An FFT along this dimension, doppler-fft, can
determine the velocity of a scatterer. As the scatterer moves, the
data corresponding that scatterer's reflections will move in
range. A doppler-fft can determine rate at which this change occurs
and the velocity.

In radar with multiple channels, such as a phased array, the datacube
has a dimension corresponding to the channels. The other two
dimensions are fast-time and slow-time.