@RogerWagner developed a microcontroller-based weather station in conjunction with collaboration on an educational project with NASA. This work could likely be adapted for integration into the Sangala initiative.
This weekend Roger ordered a LoRa (Long Range) wireless transceiver module (REYAX RYLR998) that spread spectrum technology for long-range communication with low power consumption. It uses a serial port to communicate the microcontroller. Roger had some success today in getting the weather station to communicate with a base station. He will provide further updates about the weather station and LoRa transmission technology in this strand.
LoRa (Long Range) is a spread spectrum modulation technique derived from chirp spread spectrum (CSS) technology originally developed in France. LoRa consists of multiple networking layers which includes LoRaWAN. LoRa covers the physical networking layer while LoRaWAN consists of the protocols covering the upper network layers. LoRaWAN is deployable in public or private networks providing end-to-end encryption using industry standard AES-128.
LoRa operates in the unlicensed industrial, scientific and medical (ISM) radio spectrum between 433 and 923 MHz radio frequency bands. The band in which it uses depends on the device operating conditions and country regulations. The broadcast range of LoRa is much further than Bluetooth LE reaching distances of up to 5 km (3 miles) in cities with maximum distances of up to 15km (10 miles) in rural areas. It can achieve data rates between 0.3 and 27 kilobits per second.
I have made some progress…
I have the MakerPort successfully communicating with the LoRa transceiver.
I have made a case for it to protect the antenna.
I have made enclosures for all of the components to create the development unit with the OLED display that is shown in the photo below.
I still need to get the BMP280 (temperature, humidity, pressure) sensor working with MicroBlocks, and to test the two-way communication between 2 stations.
I have made some progress…
Here is a link to a video of a MakerPort + transceiver in front of my house, receiving data from another MakerPort inside the house with the BMP280 + LoRa transceiver sending data, over a distance of about 75ft. plus the front door in between.
https://drive.google.com/file/d/1Vw7Kz0gy-WnCtgCLXrgFBmXSt19ZE56s/view?usp=sharing
In this follow up video, Roger was able to transmit and receive 120 feet in the orchard in his back yard.
Michael Littman suggested that we could also include data downloaded from weather satellites in the Sangala Weather Network. Michael has an assignment in his courses at Princeton in which students complete this as a project. This assignment makes use of a software-defined radio (SDR) and a PC. It requires about $50 in equipment.
Here is an article describing the process:
How to Download Weather Satellite Images from… | The Planetary Society
This could make a nice project for the Sangala scholars working under the supervision of the Sangala engineering teacher.
Roger ordered some externally attached antennas to see if he could achieve increased transmission range.
