GNSS Data Processing for High-Accuracy
MAD-PI Software

Dinesh ManandharCenter for Spatial Information Science
The University of Tokyo
Contact Information: dinesh@csis.u-tokyo.ac.jp

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Objectives• Learn how to process GNSS data for MADOCA-PPP using• MAD-PI : MADOCA PPP for RaspberryPi Device

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Position Accuracy and Errors

GNSS Position Accuracy:
 Red: Single Point Position
 Blue: DGPS, Code-Phase Observation
 Green: RTK, Carrier Phase Observation

GNSS Errors: Satellite Orbit Error
 Satellite Clock Error Ionospheric Delay Tropospheric Delay Receiver Clock Error
 Thermal Noise Multipath
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Data Observation Methods for High-Accuracy

Data Observation Method for DGPS / RTK / PPKData Observation Method for MADOCA PPP

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MAD-PI Setup

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MAD-PI Setup: Receiver and RaspberryPi Device

LANAntenna Cable

MADOCACompatible
GNSS Receiver

RasPi4 withTouch Screen

Micro-USB toUSB CableUSB
SD Card Connect Antenna to the GNSS/MADOCA receiver using theprovided antenna cable.
 Connect the receiver to a RaspberryPi 4 device using a“micro-USB to USB” cable.
 Connect a USB Memory Drive to RasPi device.
 Either use a Power Bank or an AC Adapter for power supply.

USB65OR50

GNSS Antenna

UT RECEIVER

Micro-USB toUSB Cable

Micro-USB toUSB Cable

PowerAdapter forRaspI4

USB Memory

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RaspberryPi Device and Software Setup
Download link is provided by UT
The Image File also contains MAD-PI software andall other necessary drivers for touch screen.

(1) Download RaspberryPi image
file from UT server

Download Link:
https://sourceforge.net/projects/win32diskimager/files/latest/download(2) Download WinDisk32Imager
program from InternetInsert or connect a new SD card into Computer.
Use an SD Card of size 8GB or more.
When selecting drive for SD Card, make sure that the drive is correct one.
If your device already has a SD card, it is not necessary to perform theabove steps from 1 – 3.

(3) Write downloaded “RasPi
image file” into a SD Card using
Win32DiskImager

RaspberryPi 4 Device

Insert the SD card into RasPi
device and Connect Power torun the device
Nee to connect an external key-board to type password.
This step is necessary to be done only once for the same WiFi AP.
If new AP has to be used, it is necessary to setup new WiFi AP once again.
You may setup multiple APs if information are already available
WiFi or internet access is necessary only if ONLINE MADOCA Correction data
to be used.
With our receiver, it is not necessary to have internet connection.

https://www.raspberrypi.com/software/

Setup WiFi in the RasPi device.
Select the WiFi name and Enter
Password

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Writing RasPi OS Image File to a Micro SD Card

Download and install the Win32DiskImager (from internet).
Download MAD-PI Image File (zipped) from UT server
Unzip MAD-PI (Disk Imager File) into your working folder.
Insert the micro SD card into the slot of your computer.
Go to This PC icon on your desktop. Check that the micro SD card is shown
under the Devices and Drives, such as Drive D.
 Do not format the card in Windows even if a message such as “..Is not
Formatted. Do you want to format?”Double click to open the Win32DiskImager. Allow to make changes to yourcomputer by clicking Yes.
Select the MAD-PI image file under Image File by clicking on the browser ( ) as
shown in the figure.
Select D: drive (micro SD card) from the drop-down box in Device.
 Make sure that this is the SD Card drive. It will erase all existing data inthe drive.
 Do not select a drive of your PC by mistake.
 Drive may be D or E or something else in your PC.
Click on Write.
 This makes the SD card ready to boot in RasPi device with all necessary
OS and MAD-PI software.
The Progress bar shows the progress of writing the disk image file into themicro SD card. Wait for the Progress bar to show 100%.
After a message is displayed that the write is successful, you can remove themicro SD card from computer.

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MAD-PI GUI• MAD-PI GUI are the same as MAD-WIN• Please check MAD-WIN document

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