An externally-connected volume of a main storage is correlated to an AOU volume inside of an external storage. This allows a field user to gather measurements made by field sensors such as depth sounders, chemical detectors and magnetometers. Each of these series of encoded symbols is subjected to a type of inverse Fourier Transform in corresponding transmission paths. The reinforcing base material is preferably made of a woven fabric and the bundling agent preferably contains as its main component thermosetting resin.