The only (legal) purpose I can see for a gain antenna in a TTN setup is in overcoming connector and cable losses, but then its just easier and cheaper to increase the gateway TX power level to compensate.
Can I use a more powerfull antenna of 3 or 5 dbi?
Sure, but remember to reduce the transmit power in the Gateway setup to ensure you stay legal.
You soon realsie that adding a gain antenna and reducing the output power(to stay legal) puts you back to square one and you dont have extra distance.
Hello
Thank for your reply.
What is the limit of the legal for Europe (France and Switzerland) There is knew recommandation.
I looked again on Digikey the Antenna. I found antenna with -2dbi and 2dbi. For wath are user the -2dbi antenna?
(As I am not realy sure about the gain reglementation, I will stay with 2dbi and not increase it)
Its assumed, in the UK at least, that the 14dBm power limit applies when using a +2.1dBi antenna.
Not sure if the limits apply to each and every possible European country, and neither do I have an intimate knowledge of the French and Swiss regulations âŠ
put a link to one, but likely they are very small antennas to be soldered on the board of a node. Not always you need extreme gain and distance, size sometimes matter more.
Mmm⊠forget my comment, those are not SMD mounted antennas. And honestly it seems strange to me that they declare lower gain. Wait for a real expert in this matter
I would suggest, before you increase antenna gain do the following.
Reduce losses on both the nodes and the gateway antenna connections.
Add a matching network on the nodes if you can.
If those donât work, then get better antennas. Often many antennas to not perform to their rating. However I have been able to achieve 5.9KM with this design from Texas Instruments. http://www.ti.com/lit/an/swra227e/swra227e.pdf
I can share gerber files of the antenna and matching network, then you can order PCB from your preferred vendor. All you need is solder on connectors and 1 SMD capacitor + 1 SMD Inductor and you are good to go.
Hello, Thank a lot for your reply. Yes I am interrested about your gerber file. I am curious to see it and a such antenna will be very usefull for my next project.
I am not na expert abour antenna, but what do you mean by reducing losse.
The Texas Intrument antenna has apparently a db of 3-4dbi, thatâs correct.
There is a loss at each connection point. Could be 0.5dB or more depending on the quality of the connectors. Reducing connectors, removing pigtails or reducing their lengths will help reduce these losses. Given the low power levels LoRa operates, such seemingly minor losses could be significant.
I have used a thin plastic box as well as cross section of a waste pipe. With the waste pipe, I had the node, antenna and battery encased. I have also used self amalgamating tape on one occasion.
We are setting up several Lora stations on farms, to go with our agricultural sensors. What would you say is the best option for fixing to the side of a bar?
For the moment we ordered 12 dBi Taoglas Braccuda, and hope to range-test it next week.
Also Iâve done some casual testing (without ttn mapper) in city and got about 900 meter range
HI @ClumsyPilot, the following is the mechanical drawing of the Taoglas OMB.868.B12F21 antenna.
I use a lot of the 5dBi equivalent of the 12dBi antenna that you have ordered. Per the mechanical drawings, I always fix them to standard 2inch/50mm telecom masts using the u-bolts that are delivered with the antenna.
You ask about attaching to the side of a âbarâ. Do you mean âbarnâ? If so then donât attach the antenna direct to the side of the barn, you need the entire antenna to stick up clear of the apex of the roof.
Are you aware that the 12dBi antenna is 2.4m long? You will need to use a substantial mast - like a scaffolding pole. The scaffolding pole is normally attached to the side of the building using standard heavy-duty telecom âT & Kâ brackets.
Following is a picture of LoRaWAN base-station using a Taoglas 5dBi (1m long) antenna mounted on a barn using T&K brackets, unistrut and a scaffolding pole. Your antenna is 2x the length of this antenna.
Depending on your ant height & assuming you GW location is near Icentrum north of Aston Uni you are doing well to get signal west to where shown on the map beyond the Childrenâs hospital. Can I suggest you do a slow driving test n/ne along the A38 Aston Expressway towards/beyond the M6 intersection. You should be getting good coverage 300-400m all around you but then extending much further in the N/E quadrant. You should hold signal to the motorway, possibly loosing some from around Aston Park and across the River Tame valley picking up again as you close on the motorway intersection. Beyond the M6 if you continue and do some war driving around Gravely Hill area you should see coverage around there you may also see signal along Victoria road between A38 & A34 and again west A34 towards Lozells on the B4144 or B4145. If you can demonstrate that then you know donât have a setup range problem but rather a topography & building clutter problem No need for exotic ant in that area as this should be achievable with a typical As Supplied GW ant e.g. A 2dbi ârubber duckâ. Should be ok for anything SF9-SF12. Only need greater sensitivity if trying to use lower SFâs for shorter on air time. Suggest you try same âdrivesâ (walks!?) with nodes @ different SFâs or repeat runs to compare and assess and with low duty cycle to avoid breaching regsâŠhence slow to get good geographic coverage without Tx gaps
No need for exotic ant in that area as this should be achievable with a typical As Supplied GW ant e.g. A 2dbi ârubber duckâ. Should be ok for anything SF9-SF12. Only need greater sensitivity if trying to use lower SFâs for shorter on air time. Suggest you try same âdrivesâ (walks!?) with nodes @ different SFâs or repeat runs to compare and assess and with low duty cycle to avoid breaching regsâŠhence slow to get good geographic coverage without Tx gaps 
