Institute for Telecommunication Sciences
the research laboratory of the National Telecommunications and Information Administration

Institute for Telecommunication Sciences / Programs / Spectrum Monitoring / Common Metadata

Common Metadata

SigMF is a simple, extensible standard for storing recorded signal datasets. The introduction to the core specification document explains why such a standard is useful:

Sharing sets of recorded signal data is an important part of science and engineering. It enables multiple parties to collaborate, is often a necessary part of reproducing scientific results (a requirement of scientific rigor), and enables sharing data with those who do not have direct access to the equipment required to capture it.

Unfortunately, these datasets have historically not been very portable, and there is not an agreed upon method of sharing metadata descriptions of the recorded data itself. This is the problem that SigMF solves.

By providing a standard way to describe data recordings, SigMF facilitates the sharing of data, prevents the "bitrot" of datasets wherein details of the capture are lost over time, and makes it possible for different tools to operate on the same dataset, thus enabling data portability between tools and workflows.

At NTIA, we have traditionally used several proprietary or internally-designed metadata formats for storing recorded signal datasets. In an effort to reduce duplication of effort and improve our ability to store and share our datasets in accordance with open data initiatives, we have developed a set of extensions to the core SigMF specification in sigmf-ns-ntia. The extensions include:

  • ntia-algorithm describes the measurement performed (detectors, algorithms, etc)
  • ntia-core adds generally useful metadata fields
  • ntia-emitter gives information about the emitter being measured
  • ntia-environment gives information about the environment around a sensor or emitter
  • ntia-location gives information about the types of coordinate systems used in the metadata.
  • ntia-scos provides metadata for the NTIA Spectrum Characterization and Occupancy Sensing (SCOS) implementation
  • ntia-sensor defines hardware components and settings
  • ntia-waveform provides metadata to describe measured or transmitted waveforms