Rationale for Activity | A major goal of CCSDS is to enhance interagency interoperability and cross-support, while also reducing risk, development time and project costs. Interoperability of mission voice communications is an enabler of mission success and mission safety.
Historically, mission voice communications within the various space agencies tend to reflect the technology and standards of the regional telecommunications industry. Though digital technologies have long supplanted analog technologies, there is a new wave of technological evolution in voice communications as disparate technologies converge, driven at least partially by the Internet and cellular phones.
Yet there remain significant interoperability issues. Even with current terrestrial technologies (e.g., 3rd generation cell phones, packet-switched networks and etc), there exist multiple boundary interfaces at which data conversion and transcoding must occur. Within large scale and high performance voice conferencing equipment, voice data must be decoded and processed in lossless digital waveform format to create the required high capacity conference loops, which then may be re-encoded for further transmission.
Voice communications with crewed vehicles was once the realm of analog RF communications and so long as participants shared common radio frequencies and modulation schemes interoperability was accomplished. Now voice is data encoded through lossy compression predictive algorithms, then multiplexed with telemetry/telecommand data, all of which may be wrapped in layers of transport headers, and finally modulated upon RF for transmission. Thus, in today’s digital world, voice interoperability among agencies can be an even greater challenge. As technologies converge there have appeared a growing number of interface boundaries.
As with the International Space Station, once a human spaceflight program is fully engaged, the magnitude of cost and schedule becomes ever clearer, and international participation is likely. Looking at three compelling future mission classes that face mankind, cost, schedule and even mission importance are drivers to international partnership. Consider:
• Moon outpost(s)
• Mars outpost(s)
• Rendezvous with a Near Earth Object (NEO)
Outposts are established goals, first on the Moon and then Mars. As current US and Chinese programs mature, cooperation may result, if not actual international participation. As lunar outposts mature the importance of science objectives increase, which provides further justification for international participation.
Rendezvous with a NEO may be a purely scientific mission to sample primordial material. However, a rendezvous may be warranted to alter the orbit of a NEO that would otherwise pass too near the Earth. (Asteroid Apophis will pass between the Earth and geo-synchronous satellites in 2029.)
There are six challenging domains as it concerns internationally interoperable mission voice communications:
• That among earthbound mission operations personnel at any number of agency, contractor, academia and private locations.
• That among space denizens, whether at an outpost in one or more structures, in single or multiple vehicles, suited and on EVA, at distance or nearby.
• That between space denizens and earthbound personnel, which includes mission operations and mission support personnel, private medical conferencing, public affairs, friends and family. At Martian distances, this will likely include recorded voice and voice to text technologies with associated metadata, using Delay / Disruption Tolerant Networking (DTN) technologies.• That between space denizens and earthbound personnel, or among space denizens, using low power emergency voice for use during a power shortage contingency.That to be used between space denizens for use during proximity and docking operations with a visiting crewed spacecraft approaching the ISS (ex. C2V2).• That between landed space denizens and earthbound personnel to be used for International Search and Rescue (SAR) operations during a contingency situation in which a returning space vehicle has landed in an unplanned location and has powered down onboard systems.
Regardless of whether exploration programs have initial requirements for cross-support between agencies, multiple manned programs in the Lunar or Mars environment will clearly require voice system compatibility for contingency or emergency operations. This work should enable that capability. |
Management Risk Mitigation Strategy | Availability of resources that can contribute to the V-WG effort. As there are no current mission schedules dependent upon the delivery of products from this WG, milestones of this WG can be rescheduled. International participation. International participation is committed by NASA and, in the long term, ESA, although current mission obligations may affect immediate participation. |