1 / 17

Aloha Proof Module Design

Aloha Proof Module Design. Cabled Observatory Presentation School of Ocean and Earth Science and Technology February 2006. Purpose. Proof of Concept Long term testing of data communications capabilities. Prepare for full observatory phase 2 deployment: Any modifications learn from phase 1

bly
Télécharger la présentation

Aloha Proof Module Design

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Aloha Proof Module Design Cabled Observatory Presentation School of Ocean and Earth Science and Technology February 2006

  2. Purpose • Proof of Concept • Long term testing of data communications capabilities. • Prepare for full observatory phase 2 deployment: • Any modifications learn from phase 1 • H4 cable cut and emplacement • Cable termination emplacement

  3. Proof Module Overview • The proof module has no supervisory command and control. • The proof module monitors engineering status, data communications, and system operation. • The proof module has no customers, but includes two internal instruments: • Wide amplitude and frequency range hydrophone • Digiquartz pressure sensor • Continuous pressure spectrum from DC to 40KHz • The proof module has no time stamp capability, but timing will be accomplished at the shore station.

  4. End Cap w/ DQ and HYD

  5. Microcontroller Power Supply DigiquartzDQ (under) .

  6. Hydrophone ADC Manchester

  7. Top ViewManchester ADC HydrophoneMicrocontroller& DQ Power Supply Digiquartz

  8. Power Supply • The proof module has a shunt regulator- based power supply consisting of three sections: • Linear Shunt Regulator • DC/DC converters • Filtering

  9. Shut Regulator Section • Input power to the shunt regulator is 12 VDC at 1.6 amps (20 watts). • This provides the input voltage to the DC/DC converters. • All power not used by the DC/DC converters is dissipated in the shunt regulator.

  10. DC/DC converter Section • The digital and analog electronic circuitry operate from two DC/DC converters: • 5 VDC @ 2 Amps Max • +/- 12 VDC @ .33 Amps Max • Due to the switching characteristic (noise) of DC/DC converters this section is enclosed in the emission-shielding metal box. • Box penetration feed-thru capacitors are used for all DC voltage and return wires. • Temperatures are monitored and also penetrate the box using feed-thru capacitors.

  11. Filter Section • A final section inductor/capacitor filter is used to provide clean noise free power. • The hydrophone is being operated with a wide amplitude dynamic range of 24 bit ADC capability. • The power supply filtering is for the analog sections: • hydrophone preamplifier, and • hydrophone analog to digital converter.

  12. Communication • The instrument data is provided over 12.288 MHz, Manchester encoded/decoded data stream. • This is 96,000 – 64-bit frames/second. • Within each frame are: • Two 24 bit digitized analog channels of the hydrophone. • Two single bit RS232 embedded serial communications 9600 baud. One primary and a secondary backup. • Six bits for frame synchronization. • Eight unused (zeroed) bits.

  13. Digiquartz • The Digiquartz is a digital pressure gauge. • 32 bit counters • Raw count (for high resolution with long periods) • Period count (for quick updates at lower resolution) • Depth is calculated from the 32kHz variable pressure sensor where frequency is directly proportional to depth. • Resolution is directly proportional to the integration time. • Temperature compensation is calculated from the 170kHz variable temperature sensor where frequency is directly proportional to temperature. • The Digiquartz is the same used in NOAA DART buoys to detect tsunami

  14. Hydrophone & ADC • The analog signal from the hydrophone is digitized with a two channel 24 bit ADC. • Channel 1 (seismic) is a wide frequency range from 100 seconds to 40 kHz. • Channel 2 (audio) is a narrow frequency range from 10 Hz to 40 kHz. • With digital sampling is 96,000 samples per second the analog is low pass filtered at 40 kHz to minimize aliasing.

  15. Serial Data Stream • The serial data stream provides both engineering and Digiquartz data. • Engineering data: • 5 DC/DC power supply voltages • 2 cable and sea water return voltages • 1 current of H4 cable • 4 temperatures • Diqiguartz data: • 2 depth & temperature period counts • 2 depth & temperature free run counts • Calculations of depth with temperature compenstaion

  16. Sample Serial Stream

More Related