Compared to a standard 1/4 wave with radials antenna, whats the relative effeciency of the PCB antenna ?
BIG product placement allowed topic
Compared to a dipole, it will be around 90-95%.
A ceramic chip antenna will have an efficiency of around 50% compared to a dipole (half dummy load!!).
An attenuation of 0.3 dB (6.7 %) will be barely noticeable while 3 dB (50% chip antenna) will be good noticeable.
More important though is the correct matching of the antenna to the transceiver chip. Nearby materials or wrong placement can easily detune an antenna resulting in a loss of 10 dB.
Our first real life tests of the antenna yielded satisfying results: 14 kilometers at 14 dBM / SF12 while the module was placed indoor on a desk with far from ideal circumstances.
Thanks for the figures, but the 90-95%, is that the actual measured value ?
This value is verified in a non-ideal situation (pre-compliance test).
The devices will be tested in nearby future in an anechoic chamber to get more accurate results.
The development kit is yet available at Onethinx.
The board contains:
- the Onethinx LoRaWAN Core module
- a 3.3V LDO regulator
- two LED’s (one blue, one red)
- a light sensor
- possibility to solder Arduino shield headers
- a push button
- a battery holder for a CR2450
- the connection to the programmer, eg. a J-Link or CY8CKIT-147
can you buy a dev kit without VAT number ?
Sure, you don’t have to fill in the VAT number.
The dev kit will be €69,- including shipping.
This is how it all began in November 2017! Hooking up the Semtech SX1272 to an early adopters PSoC6 board with Engineering Sample 2 (ES2)
First boards received.
And tested on the incredible GenComm GC747A
Getting better after some 0402 finetuning!
Measuring output power, not yet there…
And measured our the Onethinx Core main oscillator (without touching the board and influencing the capacitance) using a self constructed magnetic loop antenna and the GenComm oscillator locked to the super accurate GPS.
It’s only 1/32th of one PPM off. Incredible!!
And finally the FIRST test result out there in real world.
It’s joining on a gateway which is over 13KM away!! While having the board on my desk in far from ideal situation!
Great stuff Rolf so we have the same setup!
Glad you’re here in the forum
Yes, I saw at the workbench topic you’ve got a GenComm Analyzer as well. I’ve been searching for a VNA for a long time and have used a PocketVNA as well.
The GC747A is an incredible piece of multi-tool which is perfect for small companies or die-hard hobbyists with lots of features. I was really surprised by the dynamic range and stability of the VNA, compared to the PocketVNA. I guess the fact that it’s called LTE analyzer, this tool doesn’t come to people’s mind.
Great work you do as well!
Can you summarize the security features of the module? Thanks.
the user application runs on a physically isolated core as which the stack runs on: stack functionality and security cannot be compromised by (errors in or a malfunctioning) user application
the secure element is embedded in the same silicon (electrical interface is not exposed)
true random generator (DevNonce is not derived by reading radio noise)
the secure implementation is based on ARM PSA, which defines the secure guidelines for IoT
The user just gets a smal set of API calls to set up and do the LoRaWAN communication, without having to bother about security and or it’s implementation.
Just to show how LoRaWAN is set up.
LoRaWAN settings are done in coreConfig.
LoRaWAN _ Init(…)
LoRaWAN _Join(…) and
LoRaWAN_Send(…) are the API calls of interest.
Each function returns the complete status of the stack: parameters, radio, mac and system.
Major Discount for TTN forum members!
During Embedded World 2019 there will be a major discount for TTN forum members on our Onethinx Core DevKit.
The link to the ordering page will be posted here.
EUR 39,- excl. VAT. is a good deal ! (normal 69,-)