node-sbs1

This is a node.js module that parses ASCII messages containing Mode S ADS-B aircraft data that is in "SBS-1 BaseStation port 30003" format. This format has become a semi-standard way of sending ADS-B data.

SBS-1 messages are in a simple comma-delimited format. Here are some examples of the messages this module parses:

SEL,,496,2286,4CA4E5,27215,2010/02/19,18:06:07.710,2010/02/19,18:06:07.710,RYR1427
ID,,496,7162,405637,27928,2010/02/19,18:06:07.115,2010/02/19,18:06:07.115,EZY691A
AIR,,496,5906,400F01,27931,2010/02/19,18:06:07.128,2010/02/19,18:06:07.128
STA,,5,179,400AE7,10103,2008/11/28,14:58:51.153,2008/11/28,14:58:51.153,RM
CLK,,496,-1,,-1,2010/02/19,18:18:19.036,2010/02/19,18:18:19.036
MSG,1,145,256,7404F2,11267,2008/11/28,23:48:18.611,2008/11/28,23:53:19.161,RJA1118,,,,,,,,,,,
MSG,2,496,603,400CB6,13168,2008/10/13,12:24:32.414,2008/10/13,12:28:52.074,,,0,76.4,258.3,54.05735,-4.38826,,,,,,0
MSG,3,496,211,4CA2D6,10057,2008/11/28,14:53:50.594,2008/11/28,14:58:51.153,,37000,,,51.45735,-1.02826,,,0,0,0,0
MSG,4,496,469,4CA767,27854,2010/02/19,17:58:13.039,2010/02/19,17:58:13.368,,,288.6,103.2,,,-832,,,,,
MSG,5,496,329,394A65,27868,2010/02/19,17:58:12.644,2010/02/19,17:58:13.368,,10000,,,,,,,0,,0,0
MSG,6,496,237,4CA215,27864,2010/02/19,17:58:12.846,2010/02/19,17:58:13.368,,33325,,,,,,0271,0,0,0,0
MSG,7,496,742,51106E,27929,2011/03/06,07:57:36.523,2011/03/06,07:57:37.054,,3775,,,,,,,,,,0
MSG,8,496,194,405F4E,27884,2010/02/19,17:58:13.244,2010/02/19,17:58:13.368,,,,,,,,,,,,0

There's some documentation of the message format at http://woodair.net/SBS/Article/Barebones42_Socket_Data.htm

Here are some examples of using the module:

// Parse a string containing an SBS1 message.
var sbs1 = require('sbs1');
var s = 'MSG,3,496,211,4CA2D6,10057,2008/11/28,14:53:50.594,2008/11/28,14:58:51.153,,37000,,,51.45735,-1.02826,,,0,0,0,0';
var msg = sbs1.parseSbs1Message(s);
if (msg.message_type === sbs1.MessageType.TRANSMISSION &&
    msg.transmission_type === sbs1.TransmissionType.ES_AIRBORNE_POS) {
  console.log('coords: ' + msg.lat + ', ' + msg.lon);
}

// Connect to a server at localhost:30003 that is sending messages in SBS1
// format.  You can pass an options object containing host and port to
// createClient to connect to a different server/port.
var sbs1 = require('sbs1');
var client = sbs1.createClient();
client.on('message', function(msg) {
  if (msg.message_type === sbs1.MessageType.TRANSMISSION &&
      msg.transmission_type === sbs1.TransmissionType.ES_AIRBORNE_POS) {
    console.log('coords: ' + msg.lat + ', ' + msg.lon);
  }
});

Parsed messages

Parsed messages have the following fields:

Field	Description
message_type	See MessageType.
transmission_type	See TransmissionType.
session_id	`String`. Database session record number.
aircraft_id	`String`. Database aircraft record number.
hex_ident	`String`. 24-bit ICACO ID, in hex.
flight_id	`String`. Database flight record number.
generated_date	`String`. Date the message was generated.
generated_time	`String`. Time the message was generated.
logged_date	`String`. Date the message was logged.
logged_time	`String`. Time the message was logged.
callsign	`String`. Eight character flight ID or callsign.
altitude	`Integer`. [Mode C] 1 Altitude relative to 1013 mb (29.92" Hg).
ground_speed	`Integer`. Speed over ground.
track	`Integer`. Ground track angle.
lat	`Float`. Latitude.
lon	`Float`. Longitude
vertical_rate	`Integer`. Climb rate.
squawk	`String`. Assigned [Mode A] 1 squawk code.
alert	`Boolean`. Flag to indicate that squawk has changed.
emergency	`Boolean`. Flag to indicate emergency code has been set.
spi	`Boolean`. Flag to indicate Special Position Indicator has been set.
is_on_ground	`Boolean`. Flag to indicate ground squat switch is active.

Not all message/transmission types will have values for all fields. Missing values will be represented by null or undefined (an empty comma-delimited value is null).

Parsed messages have generated_timestamp() and logged_timestamp() methods that parse the corresponding date and time fields and return Date objects.

MessageType

There are 6 types of SBS-1 messages represented by the MessageType enum:

Enum	Value
`SELECTION_CHANGE`	`"SEL"`
`NEW_ID`	`"ID"`
`NEW_AIRCRAFT`	`"AIR"`
`STATUS_AIRCRAFT`	`"STA"`
`CLICK`	`"CLK"`
`TRANSMISSION`	`"MSG"`

SELECTION_CHANGE, NEW_ID, NEW_AIRCRAFT, STATUS_CHANGE, and CLK indicate changes in the state of the SBS-1 software and aren't typically used by other systems.

TRANSMISSION messages contain information sent by aircraft.

TransmissionType

There are 8 subtypes of transmission messages, specified by the TransmissionType enum:

Enum	Value	Description	Spec
`ES_IDENT_AND_CATEGORY`	`1`	ES identification and category	DF17 BDS 0,8
`ES_SURFACE_POS`	`2`	ES surface position message	DF17 BDS 0,6
`ES_AIRBORNE_POS`	`3`	ES airborne position message	DF17 BDS 0,5
`ES_AIRBORNE_VEL`	`4`	ES airborne velocity message	DF17 BDS 0,9
`SURVEILLANCE_ALT`	`5`	Surveillance alt message	DF4, DF20
`SURVEILLANCE_ID`	`6`	Surveillance ID message	DF5, DF21
`AIR_TO_AIR`	`7`	Air-to-air message	DF16
`ALL_CALL_REPLY`	`8`	All call reply	DF11

Only ES_SURFACE_POS and ES_AIRBORNE_POS transmissions will have position (latitude and longitude) information.

wiseman/node-sbs1

node-sbs1

Parsed messages

MessageType

TransmissionType