Summary: | During a recent experiment (April 1994), for the ONR Sea Ice Mechanics Initiative (SIMI), a portable data acquisition system was assembled that included 2 new developments. The first consists of a board, designed for the ISA PC bus incorporating 8 - 24 bit sigma-delta analog-to-digital converter (ADC) channels with 20 bit rms dynamic range. Among the features are programmable bandwidth to 1500 Hz, low power dissipation, digital anti-alias filtering, and a "floating point" mode resulting in a 16 bit word. Secondly, since the telemetry of data at continuous rates in excess of 100K bytes/s was required, hardware & software were developed to use a wireless LAN to network 3 sites up to 5km distant from the data recording system. Details of the system along with test data are described. Funding was provided by the Office of Naval Research under Contract No. N00014-91-J-1296.
|