ntia-emitter.sigmf-ext.md

The ntia-emitter SigMF Extension Namespace v2.0.0

This document defines the ntia-emitter extension namespace for the Signal Metadata Format (SigMF) specification. This extension namespace provides emitter defintion and properties.

0 Datatypes

The ntia-emitter extension defines the following datatype:

name	long-form name	description
Emitter	signal emitter	JSON Emitter object containing information describing a signal emitter, including its physical properties, emitted waveform, and environment

0.1 The Emitter Object

An Emitter object describes the physical and environmental characteristics of a signal emitter, and has the following properties:

name	required	type	unit	description
id	true	string	N/A	Unique ID of the emitter
description	false	string	N/A	Description of the emitter
power	false	double	dBm	Power referenced to antenna input
antenna	false	Antenna	N/A	Metadata that describes the antenna
transmitter	false	HardwareSpec	N/A	Metadata that describes the transmitter
center_frequency	false	double	Hz	Center frequency
waveform	false	Waveform	N/A	Metadata that describes transmitted waveform
geolocation	false	GeoJSON point Object	N/A	The location of the emitter
environment	false	Environment	N/A	Specifies the environment surrounding the emitter

1 Global

The ntia-emitter extension adds the following field to the global SigMF object:

name	required	type	unit	description
emitters	false	Emitter[]	N/A	Metadata that describe signal emitters

2 Captures

The ntia-emitter extension does not extend the captures SigMF object.

3 Annotations

The ntia-emitter extension does not extend the annotations SigMF object.

4 Collection

The ntia-emitter extension does not extend the collection SigMF object.

5 Example

{
  "global" : {
    "core:datatype" : "rf32_le",
    "core:sample_rate" : 2.8E7,
    "core:version" : "1.0.0",
    "core:num_channels" : 1,
    "core:extensions" : [ {
      "name" : "ntia-core",
      "version" : "v2.0.0",
      "optional" : false
    }, {
      "name" : "ntia-emitter",
      "version" : "v2.0.0",
      "optional" : false
    } ],
    "ntia-core:classification": "UNCLASSIFIED",
    "ntia-emitter:emitters" : [ {
      "id" : "N5182B-1",
      "description" : "Example emitter",
      "power" : 19.0,
      "antenna" : {
        "antenna_spec" : {
          "id" : "emitter-antenna",
          "model" : "Cobham_OA2-0.3-10.0V/1505",
          "description" : "Ultra Wide Band Omni Antenna",
          "supplemental_information" : "https://www.european-antennas.co.uk/media/1638/ds1505-060510.pdf"
        },
        "type" : "omni-directional",
        "frequency_low" : 3.0E8,
        "frequency_high" : 1.0E10,
        "gain" : 2.0,
        "polarization" : "horizontal",
        "cross_polar_discrimination" : 20.0,
        "horizontal_beamwidth" : 360.0,
        "vertical_beamwidth" : 65.0,
        "voltage_standing_wave_ratio" : 2.5,
        "cable_loss" : 0.15,
        "steerable" : false,
        "azimuth_angle" : 0.0,
        "elevation_angle" : 90.0
      },
      "transmitter" : {
        "id" : "tx_1",
        "model" : "N5182B",
        "version" : "v1.0.0",
        "description" : "Keysight MxG X-series RF Vector Signal Generator",
        "supplemental_information" : "https://www.keysight.com/us/en/assets/7018-03380/data-sheets/5991-0038.pdf"
      },
      "center_frequency" : 4.35E8,
      "waveform" : {
        "model" : "Waveform",
        "description" : "continuous wave"
      },
      "geolocation" : {
        "type" : "Point",
        "coordinates" : [ -79.980916, 40.304983 ]
      },
      "environment" : {
        "category" : "Underground, coal mine"
      }
    } ]
  },
  ...
  "captures" : [ ... ],
  "annotations" : [ ... ]
}