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NEEMO 14 Topside Report No. 6, May 17, 2010
05.17.10
 
NASA Extreme Environment Mission Operations

Mission Days 6-7 - "I got you loud and clear!"

Greetings!

It is important for NASA to emulate realistic communications scenarios to understand the types and quantities of video, voice, telemetry, and commands that are needed for human exploration missions. Time-delay scenarios (because of the enormous distance between Earth and other planets) are a key component to operations testing. It is also important to evaluate the level of system redundancy that is required to accomplish these human missions, and prepare for "failure modes" when problems occur. It's much better to test these concepts here on Earth than in space! As an example, on mission day 3, all broadband data connectivity from the buoy to the Aquarius habitat was lost for about 10 minutes. This data connection to Aquarius is analogous to the "dark blue" line from a lunar relay satellite to the lunar surface. The mission was able to continue through the use of analog/FM Marine radios, and the command centers could continue to talk to the crews down below. On the moon, this type of emergency voice link is provided by an S-band connection from space to the lunar surface (the "red" line on the lunar communications drawing). It's good to have redundancy when you need it!

Lunar Communications diagram
NEEMO 14 Communications diagram
NEEMO 14 Communications Architecture

The NEEMO 14 mission communications and networking architecture resembles a lunar mission architecture as closely as needed to evaluate these concepts and failure modes during these mission. The National Underwater Robotics Challenge (NURC) and NASA command centers distribute all the science data products and live webcam feeds straight from these land-based facilities. Broadband and analog/FM marine radio voice links are present between the NURC and NASA command centers on "Earth" to a NOAA Buoy 11.6 km offshore. The buoy is then hardwired with a giant umbilical cable to the Aquarius. Inside the Aquarius, the various communications services are broken out and routed to different subsystems in the habitat. During extravehicular activities, the aquanauts are linked for video and voice communications (oh yeah, and air too!) to the Aquarius habitat with long umbilicals.