ASTERIX Category 062: system tracks, translated without being re-fused

A Category 062 record is a system track message. Beyond position and velocity it carries a large volume of metadata about the correlation that produced it: per-technology update ages, per-parameter ages, amalgamation and coasting flags, the tracker's own estimated standard deviations, contributing sensor lists, and a set of last measured values standing beside the calculated ones.

The category defines one message type. Unlike Category 034 there is no per-type expectation table, so the encoding rules live in the individual data items.

Position in this category is already geodetic, which removes the projection problem that Category 048 has to solve with an externally supplied sensor position.

In most national and many coalition environments, the recognised air picture that reaches a command post has already passed through a data processing system. Category 062 is the format in which that picture is distributed.

For decision support the important property is provenance. A system track is an assertion made by a named upstream system, and treating it as ground truth erases the difference between what a sensor measured and what a tracker concluded.

Ingesting Category 062 alongside Category 048 and Category 021 lets a fused picture retain both the processed track and the reports it was built from, which is what makes a disagreement visible instead of averaged away.

One record becomes one Entity and one Event. No canonical Track is emitted and no records are combined, because combining them would be a second fusion performed inside a translator.

The tracker's statements about its own processing are collected under a fusion provenance attribute so that a consumer can see whose opinion each one is.

The adapter does not arbitrate between the altitude items, does not resolve measured values against calculated ones, does not turn contributing sensor lists into joins, and does not convert the stated ages into instants. The tracker's own formula for doing so is recorded rather than applied, because an instant computed here would be indistinguishable in the output from one the source stated.

Identity is taken from the 24-bit Mode S address, filed under the same namespace the ADS-B, Category 021, Category 048 and STANAG 4676 adapters use, so the same airframe derives the same identifier without the adapters coordinating. The track number is never used as identity.

Times are counts since the previous midnight, so the date comes from an injected clock. There is no sensor position argument and no reference point argument, and one item that would require a projection is declined rather than resolved against an assumed one.

Egress re-emits from the parsed integers, so objects that came from Category 062 produce a byte exact block.