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Digital Audio Recording Transceiver (DART)

Audio Surveillance with Digital Audio Processing for Law Enforcement and Intelligence.

Key Features

  • Wide dynamic range and high audio fidelity
  • Real-time audio monitoring using wireless communication link
  • Mono and stereo modes of operation
  • Digital recording and data storage
  • Digital data authentication
  • Large quantities of local storage
  • Triggered modes of operation
  • Indoor and outdoor operation
  • Small size and low power consumption
  • Wired and wireless monitoring and control
  • Robust data recovery protocols
  • PC-based user interface

The DART device digitizes, compresses, authenticates, stores and transmits surveilled audio. It is supported by a PC-based user interface.

High Fidelity, Digitally Recorded Audio

The DART system employs the latest digital audio intercept, monitoring and recording technologies in a flexible, highly usable DART device with unmatched audio performance. Surveilled audio is digitally recorded at the source of the audio. Digital recording enables numerical authentication and digital data compression of the original audio and allows for large quantities of local data storage in nonvolatile memory. Stored data can be transmitted in near real-time for monitoring via a wireless link and can be recovered at a later time using the same wireless link or a high-speed wired connection.

DART offers user-selectable parameters that can be configured over-the-air from a PC-based field terminal, allowing the operator to best execute the mission. The field terminal also provides for wireless recovery of stored DART data and for executing built-in tests for a deployed DART. DART incorporates design elements to conserve power for extending mission life and to provide a small form factor for aiding in concealment of the device with batteries. The DART system is designed to increase post-processing options for difficult audio collection situations characterized by high levels of external audio interference and concurrent speakers.

Features and Benefits

  • Audio Quality - Linear gain and 16-bit digitized audio sampled at up to 24 kHz provides wide dynamic range and high audio fidelity.
  • Authentication and Integrity - Digitized audio samples are signed with a unique digital signature generated by industry standard data authentication algorithms. Each DART module contains a unique identification number that is burned into the internal processor silicon at the time of manufacture and is used in data communication.
  • Indoor and Outdoor Operation - The DART module is tested to outdoor unsheltered operating temperature ranges, and the electronics are enclosed in an aluminum housing designed to meet IP-65 splash resistance.
  • On-Device Digital Storage - Onboard CompactFlash, currently the most memory dense solid-state memory technology, provides on-device storage for audio at the highest level of fidelity. Compressed audio storage modes (at reduced audio fidelity) can increase the amount of on-device audio storage time by a factor of 6 with a quality that surpasses .mp3 recording.
  • Triggered Recording - The DART module can operate in a mode that conserves battery power and memory by waiting to record until an internal sound detector and/or an external input, such as from a motion detector, activates.
  • Dual-Channel Recording - The DART device includes mono and stereo modes using one or two external microphones.
  • Power Conservation Techniques - Perhaps the greatest feature of the DART design is the power management implementation, which permits major sections of the DART processing electronics to be turned off to extend operational life and meet aggressive mission duration requirements on a single set of batteries.
  • Configurable Operating Parameters - A simple though highly capable user interface running on a PC allows operating parameters to be tailored to meet specific mission objectives for audio recording trigger, fidelity, monitoring, recovery and other operating characteristics.
  • Wired/Wireless Monitoring and Control - An internal radio modem provides operator control of configurable operating parameters and supports near real-time monitoring along with retrieval of audio information stored in the device memory. A wired interface provides for high-speed serial communication via a cable.
  • User Interface - A user interface running on a PC provides for command and control of the DART, configuration of operating parameters, monitoring, and recovery of data. The user interface is capable of verifying the authenticity of the recovered recordings, storing the recording to CD or DVD, splitting and/or merging recordings for ease of analysis, and exporting the data to .wav files that can be played using standard media players.

For more information, contact James A. Moryl, Director, Surveillance and Geolocation Department.

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April 15, 2014