polypoint

PolyPoint
=========

<img src="https://raw.githubusercontent.com/lab11/polypoint/master/media/polypoint_logo_a.png" alt="PolyPoint" width="20%" align="left">

PolyPoint is a system for using ultra-wideband RF time-of-flight ranging to perform indoor localization.
It incorporates the DecaWave DW1000 for UWB packet transmission and timestamping
into a solder-on module that provides node-to-node ranges over an I2C interface.



Name
----

The name PolyPoint comes from the use of many polygons and shapes in the prototype design and the
desire to pinpoint where users are with the system.


Git Clone
---------

When cloning this repository, be absolutely sure to do

    git clone --recursive https://github.com/lab11/polypoint.git
    
so that you get the submodules as well. All of the supporting
libraries and build tools are in submodules for the various
hardware platforms used in this project.


Hardware
--------

The PolyPoint system is composed of several hardware pieces. At the core is the
TriPoint module which is a 1.25" on a side triangle that encompasses all of the
core ranging hardware and software. TriPoint has castellated edges and can be
soldered on to a carrier board, effectively as a ranging IC. TriTag is one such
carrier board designed to be the tag in the ranging system. It includes the
UWB antennas and a Bluetooth Low Energy radio plus a battery charging circuit.
TriTag is able to provide ranges to a mobile phone application.

### TriPoint

TriPoint includes the following components:

- DecaWave DW1000 UWB radio
- STM32F031G6U6 MCU
- RF switch

The MCU contains all the necessary code to run the DW1000 and the ranging
protocol.

### TriTag


  <img src="https://raw.githubusercontent.com/lab11/polypoint/master/media/tritag_blue_1000x889.jpg" alt="TriTag" width="20%;" align="right">


TriTag includes:

- The TriPoint module
- 3 UWB antennas
- nRF51822 BLE radio
- 3.3 V LDO
- Li-ion battery charger

TriTag is designed to be the tag to be localized in the system and connected
to a smartphone.


### TriDev

TriDev is a breakout and testing board for the TriPoint module.
It contains the same BLE hardware as TriTag, but also adds an FTDI
chip for issuing I2C commands over USB.


Software
--------

PolyPoint contains many software layers that run at various levels of
the system.

#### TriPoint

The core firmware that makes the drop-in TriPoint module work
includes all of the logic to implement two way ToF ranging
on top of the DecaWave DW1000 UWB radio. The firmware architecture
supports multiple "applications", or ranging algorithms, that can
be selected at runtime.

#### TriTag

The TriTag code implements a BLE application
that uses the TriPoint module as an I2C device and provides
a BLE service. It puts the TriTag hardware into TAG mode
and provides ranges over a BLE characteristic. 

#### Phone and BLE

The tools in the `/phone` directory interact with TriTag and read data
across the BLE interface.