Geocell
The Google Maps Geolocation API actually lets you define multiple gsm
cell towers into its request. But it will just return the location and
accuracy based on the first cell(serving cell), doing nothing meaningful
about the neighbour cells, rssi and timing advance values.
So this is an attempt to do something a bit more meaningful...
Installation
Use pip:
::
pip install geocell
Or clone the repo and:
::
pip setup.py install
Setting your Google Maps API Key
The key will be used in:
- Google Maps Geolocation API for requesting cell locations
- Google Maps Javascript API for drawing maps
If you don't have a google maps api key. Go
here <https://developers.google.com/maps/documentation/javascript/get-api-key>
__
and follow the instructions to get your key.
Set your api key using either of the following methods:
- Set your key as the
GOOGLE_MAPS_API_KEY
environment variable import geocell
then geocell.api_key="<your api key>"
Usage
Simple location request
.. code:: python
>>> import geocell
>>> sample_cell = {"mnc":2,"mcc":286,"cid":51861,"lac":54110}
>>> geocell.locate(sample_cell)
{'location': {'lat': 40.7018889, 'lng': 29.8912834}, 'accuracy': 3250.0}
Location Estimation
~~~~~~~~~~~~~~~~~~~
We need the rssi values and multiple cell information to make an
estimation
.. code:: python
>>> sample_cells = [
... {"rssi":-82,"mnc":2,"mcc":286,"cid":51861,"lac":54110},
... {"rssi":-85,"mnc":2,"mcc":286,"cid":16116,"lac":54110},
... {"rssi":-93,"mnc":2,"mcc":286,"cid":0,"lac":54108},
... {"rssi":-94,"mnc":2,"mcc":286,"cid":38344,"lac":54110},
... {"rssi":-97,"mnc":2,"mcc":286,"cid":52555,"lac":54110},
... {"rssi":-98,"mnc":2,"mcc":286,"cid":51857,"lac":54108},
... {"rssi":-99,"mnc":2,"mcc":286,"cid":39684,"lac":54110}
... ]
>>> geocell.estimate(sample_cells)
{'location': {'lat': 40.70356939393244, 'lng': 29.88564243119295}, 'accuracy': 251.3839360809747}
.. NOTE::
You will notice that this function takes couple of seconds to
return, the reason is that the *Google Maps Geolocation API*
requests take some time. But the cell requests are cached internally
in the module so the next time you request the same cell, the value
will be returned instantly. If you like, you can also set
``geocell.is_multiprocess = True`` to do multiple requests, just
don't use multiprocessing inside a interpreter, it doesn't like it.
Let's see it in action now:
.. code:: python
>>> geocell.estimate(sample_cells, "map.html")
{'location': {'lat': 40.70356939393244, 'lng': 29.88564243119295}, 'accuracy': 251.38393
60809747}
Looking at the generated map:
- **Light yellow circle** is the serving cell
- **Red colored** are the neighbour cells
- **The blue lines** are the flight path showing estimation done at
each step. Starting point of the flight path is the center of the
serving cell
- **The marker** shows the end of the flight path and the last
estimated location
.. figure:: https://cloud.githubusercontent.com/assets/3398029/18313982/d0a5a9a0-7519-11e6-99e3-70743cffdf78.jpg
:alt: all
Let's take a closer look:
.. code:: python
>>> geocell.estimate(sample_cells, "map_estimate.html", cell_display="estimate")
{'location': {'lat': 40.70356939393244, 'lng': 29.88564243119295}, 'accuracy': 251.38393
60809747}
Now the map shows only the estimated location(marker) and estimated
accuracy(radius). The arrow points to the actual location.
.. figure:: https://cloud.githubusercontent.com/assets/3398029/18313986/d32f370e-7519-11e6-9250-6ae622daf013.jpg
:alt: estimate