tetra-sds

Tetra Advanced Radio Digital Information System

T.A.R.D.I.S (I wanted it to spell TARDIS OK.)

Decodes Tetra Terrestrial Trunked Radio Time and Location Data in Time and Space...

Based on the ETSI Standard: https://www.etsi.org/deliver/etsi_ts/100300_100399/1003921801/01.03.01_60/ts_1003921801v010301p.pdf

Overview

Tetra is a digital two-way radio standard, used not only for voice but for Short Data Services (SDS) as well. This project is a python implementation for decoding said data.

Usage

Input the SDS data as a hex string or raw binary, outputs a dictionary with location, velocity, direction and time information. Data can be from a database binary blob, a text file, csv or directly from a Tetra Air Interface API.

import tetra-sds.decode as decode

data = decode.sds(hex_string)
print(data)

Then get the values from the returned dictionary, print it to get the layout.

latitude = data['location']['latitude']['decimal_degrees']
longitude = data['location']['longitude']['decimal_degrees']
speed = data['velocity']['kmh']

# ...etc.

It also may be of benifit to sort by epoc (ascending)

locations = sorted(locations, reverse=False, key=lambda k: k['time']['epoc']) 

Do what you wish with this data, such as create a list of lat,lon tuples or convert it into a geojson.

path = [ (pos['location']['latitude']['decimal_degrees'], pos['location']['longitude']['decimal_degrees']) for pos in locations ]

Design

The various data types are matched in the "lookup.py" file.

Processed data is stored in dictionaries. Those dictionaries are then combined into the "master" dictionary.