A High-Speed, Multi-Channel Data Acquisition System

The Naval Research Lab is currently conducting research programs in MCM detections and classifications using both low and high frequency acoustics. These include target detections, target imaging, proud and buried target detections and classifications using structural clues. To determine the limitations that a fluctuating environment places on these target detection methods, a data acquisition system was developed. The data acquisition system consists of multi-channel, high-speed A/D's with remote, variable gain control, and FPGA technology. Each A/D is synchronously sampled at a rate of 1 MHz and using time -division multiplexing techniques, is sent down an optical fiber at 1.3 Gbps. The sampled data is then separated back to its original channel and recovered back to an analog signal along with the original clock. Precision filters and high speed transient recorders utilizing fast CAMAC crate controllers are then employed to sample, simultaneously, all data channels with sample rates up to 3Msps. Acoustic and environmental real-time software were developed using National Instruments Labview to generate the CW source signals that went from 10 kHz to 200 kHz, monitor acquired data, and control sample and repetition rates.