6.1.8) LoRa Experiments

1) Experiment Overview

Currently, this LoRa experiment operates in TESTBED mode and focuses on transmitting timestamped packets via the LoRaWAN network deployed at AERPAW's Centennial Campus and Lake Wheeler Field. The setup includes a single AERPAW SPN portable LoRa node equipped with a LoStik device.

The setup involves one AERPAW SPN LoRA portable node with a Lostik device connected.

Experiment Goals:  Collect key metrics such as RSSI, SNR, drone location, DataRate, Frequency, Spreading Factor, RX_Channel, and Gateways location.

Output Result files: The experiment will generate vehicle and LoRaWAN transmission logs. For detailed TX-RX package parameters with location data, contact the AERPAW LoRaWAN operators after finalizing the experiment.

2) Modifying the Experiment Configuration Parameters:

The LoRaWAN parameters can be configured opening with your favorite text editor in the config.txt file located at:

/root/Profiles/ProfileScripts/Radio/Samples/LoRaWAN/SendPackageLostik/config.txt

Most Common Configuration Parameters:

The Configuration parameters allowed to change are the following:

• JOIN_MODE (abp/otaa - Defines the network activation mode)

  1. APPEUI (Application identifier for OTAA activation)

  2. APPKEY (Application key for OTAA activation)

  3. DEVEUI (Device identifier for OTAA activation)

  4. RETRIES (Number of retry attempts for network joining or transmission)

• LORA_PORT (Serial port used to communicate with the LoRa module, e.g., /dev/ttyUSB0)

• # ABP Session Parameters

  1. DEVICE_EUI (Unique identifier for the device, hexadecimal string)

  2. APP_SESSION_KEY (Application session key for ABP activation, hexadecimal string)

  3. NET_SESSION_KEY (Network session key for ABP activation, hexadecimal string)

  4. DEVICE_ADDRESS (Device address for ABP activation, hexadecimal string)

• LORA_BAUD (Baud rate for serial communication with the LoRa module, e.g., 57600)

• ar (Enable/Disable Automatic Reply - on/off)

• MIN_DR (Minimum data rate for transmissions, range: 0-4)

• MAX_DR (Maximum data rate for transmissions, range: 0-4)

• MIN_CH (Minimum channel number used for transmissions, range: 1-100)

• MAX_CH (Maximum channel number used for transmissions, range: 1-100)

• ch_drrange (<channelID> <minRange> <maxRange> - Defines data rate ranges for specific channels; e.g., 13 4 2 means channel ID 13, min DR=4, max DR=2)

• pwridx (Output power index for transmissions on the US frequency band, range: 5-10)

• class (LoRaWAN device class; a for Class A, c for Class C)

• retx (Number of retransmissions for confirmed uplink packets, range: 0-255)

• adr (ON/OFF - Enable/Disable Adaptive Data Rate mechanism)

• portno (<portno>, range: 1-223 - Application port number used to distinguish payload types within LoRaWAN frames)

Reference on how to modify the parameters: Microchip Reference Guide RN2903

3) Performing the Experiment

The relevant scripts for this experiment are located in the /root/Profiles/ProfileScripts/Radio/Samples/LoRaWAN/ directory, These include:

• config.txt: Previously described, this file is used to configure LoRaWAN parameters.

• sendVehiclePackage.py: A Python script that enables real-time monitoring and transmission of package data over LoRaWAN, configures the LoStik device, and dynamically adjusts transmission settings.

• startSendVehiclePackage.sh: A shell script that automates the execution of the sendVehiclePackage.py Python script for LoRaWAN data transmission.

Portable Node SPN LoRa:

Login to the portable node E-VM and navigate to the folder containing all the radio scripts:

$ cd /root/Profiles/ProfileScripts/Radio/Samples/LoRaWAN/SendPackageLostik/

Edit the config.txt file parameters if needed:

$ nano config.txt

Copy the start experiment script from the current directory as startRadio.sh:

$ cd /root/Profiles/ProfileScripts/Radio

$ cp Samples/LoRaWAN/SendPackageLostik/startSendVehiclePackage.sh startRadio.sh

Use an editor to uncomment the line /Radio/startRadio.sh  and /Vehicle/startVehicle.sh in /root/startexperiment.sh 

Create a preplanned trajectory for the drone of your preference for the experiment, you can follow the instructions for creating a preplanned trajectory in the following link:

Preplanned Trajectory

and then run:

$ sh /root/startexperiment.sh

For stoping the experiment you can run the following command:

$ sh /root/stopexperiment.sh

If you want to Reset the experiment:

$ sh /root/reset.sh

Understanding the logic:

If you need to check or modify the experiment, you can review the support files located at /root/Profiles/ProfileScripts/Radio/Helpers/LoRaWAN/. In this directory, you will find the following files:

• config.py

• logger.py

• lora_connection.py

• read_last_line_uav_results_folder.py

These files allow you to add or adjust setup parameters as explained in the Microchip Reference Guide RN2903. Additionally, you can modify the configuration for the OTAA (Over-The-Air Activation) connection as needed.

Terminal Setup for LoStik Device

The terminal interface allows you to send commands directly to the LoStik device for testing and configuration, as shown in the shared image. You can input commands like mac get deveui or sys get ver to retrieve specific device information or settings. The terminal provides feedback in real-time, displaying the command status and the corresponding output.

1. Copy Start Script

cd /root/Profiles/ProfileScripts/Radio  

cp Samples/LoRaWAN/TerminalTestLostik/startTerminalLostik.sh startRadio.sh

2. Run the Experiment

Uncomment the line in /root/startexperiment.sh --> # /Radio/startRadio.sh  

sh /root/startexperiment.sh  

3. Access the Terminal:

After running the startexperiment.sh script in the /root  the experimenter can use the following command to open a screen and send commands to Lostik:

$ screen -r send_loRaWAN_vehicle_pkg

To exit the screen without stopping the process, press Ctrl+A followed by D.

Stop/Reset:

sh /root/stopexperiment.sh  # Terminate  

sh /root/reset.sh          # Reset configurations  

⚠️ Critical Note

Do not run the terminal experiment (terminal_lostik_loRaWAN) and the send package experiment (send_loRaWAN_vehicle_pkg) simultaneously.

Use screen -r [session_name] to monitor only one experiment at a time.