nuked field-tests section

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sigmahour 2022-11-03 22:46:16 -04:00
parent c9e932bb8a
commit a50c99ff7a
7 changed files with 35 additions and 44 deletions

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@ -11,7 +11,7 @@ Meshtastic® is a project that enables you to use inexpensive LoRa radios as a l
### Features
- Long range ([_166km record by Puzzled Pancake_](/docs/about/overview/field-tests/range/#current-record))
- Long range ([_166km record by Puzzled Pancake_](/docs/about/overview/range-test#current-record))
- No phone required for node to node communication
- Encrypted communication
- Excellent battery life (LoRa radios have a very low power draw)

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@ -1,7 +0,0 @@
position: 7 # float position is supported
label: 'Field Tests'
collapsible: true # make the category collapsible
link:
type: generated-index
title: Field Tests
slug: field-tests

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@ -1,36 +0,0 @@
---
title: Testing LoRa Antennas
sidebar_label: LoRa Antennas
sidebar_position: 1
---
If you have sufficient range with your existing aerial, skip this section. If you don't, consider either getting more nodes and / or replace the stock aerial with one tuned (to your region transmitter's frequency):
- A quarter wave _tuned_ stubby aerial (<10cm for fit-in-pocket) should have a real-world range of a couple of km without significant obstacles (buildings / hills).
- Aerial criteria: 50 Ohm, appropriate connector (usually SMA male or U.FL), low VSWR (<2) (at tuning frequency - see its datasheet), gain > 0 dBi .
- Caution, avoid suppliers who:
- don't state the aerial's tuned frequency and its specific purpose (LoRa network)
- claim huge gain figures on omni-directional aerials
- don't provide boringly professional datasheets
If you want more range, directionality, or specificity read on.
## General guidance
The Meshtastic system is designed to be simple and intuitive to use. However, its LoRa radios rely on point-to-point communications, unit-to-unit, aerial-to-aerial; quite different to the near ubiquitous radio coverage of today's cellphone & Wifi connections.
Some understanding of the factors affecting radio communications will help achieve substantially better service and faster transmission over a greater range with your devices. Here, we'll attempt to provide a top-level set of guidance for use and aerial selection, how to test the aerials, a set of resources for further research, and plenty of opportunity for going deeper.
The Meshtastic devices (of various flavors) lend themselves to experimentation, not only because you can replace their aerials, but also because of their mesh operation. All nodes will, without alteration, relay communications from any other members of the mesh around obstacles and over greater distances. The cost of aerial investment should be weighed against investment in additional low-cost nodes.
:::caution
While the LoRa devices we are using for Meshtastic are relatively low power radios, care should be taken _not_ to operate any radio transmission device without an aerial or with a poorly matched aerial. Un-transmitted radio signal reflected back to the transmitter can damage the device.
:::
The information collected here is by no means definitive, and necessarily abbreviated (it's a huge topic).
## Discussion
To comment on / join in antenna range [Meshtastic discourse](https://meshtastic.discourse.group/t/antenna-improved-range/227/35?u=sens8tion)
There, you will also find reference to Meshtastic range achievements and aerial recommendations. (Note we've stopped short of making specific supplier aerial recommendations in this wiki.)

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@ -7,6 +7,32 @@ sidebar_position: 1
Testing of antennas can be both simple and complex. At its simplest, testing involves sending messages from different locations and seeing which ones are received, and then comparing the results against other antennas. At the complex end, this can be using expensive test chambers and equipment to measure the signal strength, gain, and radiation patterns. However, it seems that a reasonable job can be done with cheaper methods.
If you have sufficient range with your existing aerial, skip this section. If you don't, consider either getting more nodes and / or replace the stock aerial with one tuned (to your region transmitter's frequency):
- A quarter wave _tuned_ stubby aerial (<10cm for fit-in-pocket) should have a real-world range of a couple of km without significant obstacles (buildings / hills).
- Aerial criteria: 50 Ohm, appropriate connector (usually SMA male or U.FL), low VSWR (<2) (at tuning frequency - see its datasheet), gain > 0 dBi .
- Caution, avoid suppliers who:
- don't state the aerial's tuned frequency and its specific purpose (LoRa network)
- claim huge gain figures on omni-directional aerials
- don't provide boringly professional datasheets
If you want more range, directionality, or specificity read on.
## General guidance
The Meshtastic system is designed to be simple and intuitive to use. However, its LoRa radios rely on point-to-point communications, unit-to-unit, aerial-to-aerial; quite different to the near ubiquitous radio coverage of today's cellphone & Wifi connections.
Some understanding of the factors affecting radio communications will help achieve substantially better service and faster transmission over a greater range with your devices. Here, we'll attempt to provide a top-level set of guidance for use and aerial selection, how to test the aerials, a set of resources for further research, and plenty of opportunity for going deeper.
The Meshtastic devices (of various flavors) lend themselves to experimentation, not only because you can replace their aerials, but also because of their mesh operation. All nodes will, without alteration, relay communications from any other members of the mesh around obstacles and over greater distances. The cost of aerial investment should be weighed against investment in additional low-cost nodes.
:::caution
While the LoRa devices we are using for Meshtastic are relatively low power radios, care should be taken _not_ to operate any radio transmission device without an aerial or with a poorly matched aerial. Un-transmitted radio signal reflected back to the transmitter can damage the device.
:::
The information collected here is by no means definitive, and necessarily abbreviated (it's a huge topic).
## Range Testing
As mentioned, while stating the obvious, the simplest way of performing a test is:
@ -61,3 +87,11 @@ For a bit of light reading on environmental research:
In summary - wavelengths in Europe fair well in plain sight, curve over not-so-tall obstacles (including trees), and they reflect off surfaces at low angles of incidence. They go through humans without much attenuation; but not brick, stone, or anything with more attenuation than glass / Kevlar. Oh, and dont sit under an LTE tower and expect it to be plain sailing. RF emissions at adjacent frequencies can interfere at a high enough power.
## Discussion
To comment on / join in antenna range [Meshtastic discourse](https://meshtastic.discourse.group/t/antenna-improved-range/227/35?u=sens8tion)
There, you will also find reference to Meshtastic range achievements and aerial recommendations. (Note we've stopped short of making specific supplier aerial recommendations in this wiki.)