LoRaWAN range experiments

With my indoor gateway, a basic Dragino LPS8, i was able to receive packets from over 500 meters distance, with the standard indoor antenna and the gateway positioned near a window about 10m above ground. I read on the TTN forum that it is possible to increase the coverage by using an external antenna, and i bought the Dragino BLG-AN-040 kit (915MHz version, good for 902-928Mhz) that has 40cm fiberglass antenna with a 3dB gain. The antenna cable is only 60cm so i had to put the antenna very close to my roof door, under the solarPV panels.

Fortunately the WiFi signal is strong enough with the router 2 floors down. But the gateway, configured as TTN Basic Station is still rather unstable, as other people have also reported on the TTN forum. It seem the Dragino firmware for Basic Station has some problems that makes the gateway lose its WiFi connection, and also from time to time completely freezes the gateway requiring a manual power cycle. To monitor this, i added a cron job on the gateway to post its uptime to my Thingsboard server.

In order to test the range improvements of the external antenna, i assembled a LoRaWAN tracker node based on the simple PCB i designed for my river level application. The tracker consists of:

• an ESP32-WROOM microcontroller
• an Ra-01H LoRa module with spiral antenna
• an MCP1826S 3.3V LDO
• a voltage divider to measure the battery voltage
• a 18650 Lithium cell with TP4056 charger module

I used the same sketch as in my previous post (forcing SF7, no ADR) and after linking this device to the TTN Mapper mobile app, I went for a hike around the Mui Wo valley. The results were quite impressive, with successful transmissions up to 2.5km away, especially on the mountain ridge (700m altitude) with a clear Line of Sight.

This shows up on the TTN Mapper homepage as below, but you can check the details using the Advanced Maps tab with Gateway ID “cassiopeia-lps8” as above.