LoRa/LoRaWAN tutorial 46: Collinear Antenna

If you like this video and want to support me, go this page for my donation Paypal or crypto addresses: https://www.youtube.com/c/mobilefish/about This is part 46 of the LoRa/LoRaWAN tutorial. In this tutorial I will explain what a collinear antenna is and how to build one. A collinear antenna is actually an array of dipole antennas stacked one above the other so that they are all in a straight line, i.e., "co linear." On internet you can find several designs how to build a collinear antenna: Collinear antenna 1 https://www.thethingsnetwork.org/forum/t/diy-external-antenna-for-gateway/3011 Collinear antenna 2 https://github.com/IRNAS/ttn-irnas-gw/ I have build both antennas and will demonstrate how these antennas performs in this tutorial. Please note: I have made some modifications to both designs. Collinear antenna 1 4NEC2 card deck: https://www.mobilefish.com/download/lora/collinear_868mhz_4nec2.nec.txt A more accurate procedure how your antenna actually performs in the real world: https://github.com/LoRaTracker/AntennaTesting More information about the end node, see: https://www.mobilefish.com/developer/lorawan/lorawan_quickguide_build_lora_node_rfm95_arduino_pro_mini.html The end node uses the MCCI LoRaWAN LMIC Library: https://github.com/mcci-catena/arduino-lmic The end node uses the following sketch: https://www.mobilefish.com/download/lora/ttn-otaa-pro-mini-sensors.ino.txt Google map with gateway locations: https://drive.google.com/open?id=18SKbHVEIFHU6YjzYpgZL98vuHcmV4OPQ&usp=sharing Collinear antenna 1 performance test A logged data: https://www.mobilefish.com/download/lora/collinear_test_results.txt Collinear antenna 1 performance test A tilted logged data: https://www.mobilefish.com/download/lora/collinear_test_results2.txt Collinear antenna 1 performance test B logged data: https://www.mobilefish.com/download/lora/collinear_antenna_gain.txt Collinear antenna 1 conclusion Based on the results of performance test A and B, I conclude that the collinear antenna 1 performance is quite similar to the ½λ dipole antenna. If I ONLY look at elevation angles (α) between -1° and 3°. This assumption is supported by comparing the 4NEC2 radiation pattern in the vertical plane between the ½λ dipole antenna and the collinear antenna 1 at elevation angles (α) between -1° and 3°. Collinear antenna 2 4NEC2 card deck: https://www.mobilefish.com/download/lora/collinear2_868mhz_4nec2.nec.txt Collinear antenna 2 performance test A logged data: https://www.mobilefish.com/download/lora/collinear2_test_results.txt Collinear antenna 2 performance test B logged data: https://www.mobilefish.com/download/lora/collinear2_antenna_gain.txt Collinear antenna 2 conclusion Based on the results of performance test A and B, I conclude that the collinear antenna 2 performance is much better compared to the ½λ dipole antenna. More gateways in my area were able to receive the transmitted sensor data. This is also collaborated looking at the 4NEC2 radiation pattern in the vertical plane and the fact that all my nearby gateways operates at an elevation angle (α) between -1° and 3°. Collinear antenna 2 has a better antenna performance compared to collinear antenna 1. More gateways were able to receive the transmitted sensor data using collinear antenna 2 compared to collinear antenna 1. Collinear antenna 2 has a higher gain at elevation angles between -1° and 3° compared to collinear antenna 1, according to the 4NEC2 radiation patterns in the vertical plane. The 4NEC2 program simulates how the antenna behaves but MY collinear antennas are not accurately modelled. Which means that the generated radiation patterns and other antenna parameters are just a rough indication of how the real collinear antennas behaves. If you want accurate radiation patterns and other antenna parameters, these antenna measurements should be performed in an anechoic chamber. If a collinear antenna is put inside a plastic / glass fiber tube, always measure the antenna parameters with an antenna analyser when the antenna is inside the tube. It is possible to put the collinear antenna inside a PVC tube, but use a thin tube wall. Gray PVC tubes may contain carbon. Carbon absorbs or reflect RF signals. To check if the PVC tube contains carbon, you can apply the "microwave" method. The microwave method is explained at: https://www.thethingsnetwork.org/forum/t/diy-external-antenna-for-gateway/3011/17 WARNING: IF YOU APPLY THE MICROWAVE METHOD, IT MAY DESTROY YOUR MICROWAVE. DO THIS AT YOUR OWN RISK! Check out all my other LoRa/LoRaWAN tutorial videos: https://www.youtube.com/playlist?list=PLmL13yqb6OxdeOi97EvI8QeO8o-PqeQ0g Subscribe to my YouTube channel: https://www.youtube.com/channel/UCG5_CT_KjexxjbgNE4lVGkg?sub_confirmation=1 The presentation used in this video tutorial can be found at: https://www.mobilefish.com/developer/lorawan/lorawan_quickguide_tutorial.html #mobilefish #lora #lorawan