LoRa-Tracker-Communicator

LoRa-Tracker is a device designed to provide an autonomous, encrypted radio data transmission channel between android devices (phones, tablets) or between PCs, within a radius of up to 6 km. This, in conditions of complete absence of mobile GSM communication and the Internet, will provide the possibility of receiving on phones  information about the location of other LoRa-Trackers, the ability to send text chat messages between phones, and also enables remote activation (within a radius of up to 6 km) of turning on/off devices and receiving information from remote sensors. LoRa-Tracker connects to a phone via Bluetooth or to a PC via RS-232.

1 LoRa-Tracker-Communicator provides solutions to the following tasks:

1.1 Information transfer via LoRa, RS-232 and Bluetooth interfaces;

1.2 Radio channel function:

When connected to an android phone via bluetooth, LoRa-Tracker provides an autonomous, encrypted radio transmission channel with other phones as well connected to other LoRa-Trackers

1.3 Tracker function:

Each LoRa-Tracker can determine its location using an internal GPS module, and forward this data to other LoRa-Trackers, by joining a LoRa-Tracker with a phone, you can track the location of other LoRa-Trackers on the map.

1.4 Communicator function:
After joining a LoRa-Tracker on your phone, you can send text messages to other LoRa-Trackers and read received messages on other phones, and you can also transfer small files between phones.

1.5 Radio modem function:

LoRa-Tracker in radio modem mode can be connected via RS-232 to a computer or other device and organize a radio transmission channel with another remote computer or device.

1.6 Encryption function:

By enabling the encryption function, the transmitted data will be encrypted and transmitted to be read this data on another device, you need to enter the key.

1.7 Remote device control function

The LoRa-Tracker can be connected to devices and sensors that can be controlled from other remote LoRa-Trackers.

2. Technical characteristics:

2.1 Operating radius - up to 6 km;

2.2 Frequency of data transmission by default - 446.125 MHz (channel selection from 410.125 MHz to 493.125 MHz)

2.3 Data transmission power at a frequency of 446.125 MHz by default - 0.5 W (the power can be selected - 0.125 W,      0.25 W, in emergency cases - 1 W);

2.4 Data encryption parameters:

2.4.1 Encryption in LoRa - 2 bytes=16 bits (216=65536 options);

2.4.2 Encryption in the controller STM32U545 (LoRa-Tracker option with installed controller STM32U545RET6QTR) 128 bits (2128 =1038 options) ;
2.5 Input power USB TypeC (5V);

2.6 Maximum consumed  peak power - 4 W;
2.7 Interfaces - LoRa (antenna pin on the case or external cable), RS-232 and Bluetooth; 2.8.1 Light and sound indication;

2.8 Power of the device that can be turned on/off remotely - up to 25 W (Umax=25 B );

2.9 Controls and indicators - Lora-Tracker has buttons with light indication, and sound indicator;

2.10 Working temperature from minus 25 to +70 degrees;

2.11 Budget Lora-Tracker with controller  STM32L431 and more expensive with an STM32U545 controller (a controller with a built-in AES hardware encryption unit).

How does addressing work, who receives a message from the network and who does not, there are two broadcast modes for this:

option 2 (radio broadcast) is the transmission of a message to all  who is tuned to a certain channel, which is indicated in the message, to which address the receivers are tuned, it doesn't matter

Current project status:

1. Developed circuit and controller board and power and switching board.
2. Completed installation of two prototypes of controller boards.
3. Developed TOR for the first stage of software development with a simplified list of main functions.

      Calculation of the approximate cost of one product (without taking into account the cost of software development) when using the package from Aliexpress ( UAH):

200 (body) + 300 (circuit boards - 2 pcs.) + 100 (bluetooth module) + 800 ( gps module) + 600 (LoRa module) + 100 (controller) + 800 (other products) + 1500 (labor payment) + 200 (batteries 18650 - 2 pcs) = UAH 4,600.

A remotely similar project is being developed in Ukraine under the name “Himera”