1W 6 dBi gateway

Gateways
1

Hello,

I’d like to know if anyone already have built a gateway at max allowed power. My plan is to install a 1W gateway with a 6 dbi antenna, thus matching the maximum allowed EiRP in Canada.

Just a little more details, I live in a rural area, my goal is to get the maximum coverage distance (omnidirectionnal) in compliance with ISDM’s regulations. I already have a 116’ ham radio tower, so height of the station will be near that.

As of now, I am only able tout find 22 dbm gateways, leading to an already high 8 dbm under maximum. Anyone knows if I could use a 8 db low-noise amplifier? If so, what is the hardware that you would recommand?

Overall, what hardware would you use to complete this project?

Thanks,
Acrilex

2

Which TTN software are you using ?

Does it support the use of an antenna sequencer or complete isolation of transmit and receive channels ?

3

I have made no software choices, the only final goal is to have an idea of a gateway design, the rest is not important for now.

I am actually just at the step of designing the gateway. My goal, for it to be clear, is:

  • Highest possible power and EiRP in Canada
  • Relatively low cost (I am more than open to DIY, the only thing to know is that solutions at 500$ for gateway alone aren’t realistic to my budget)
  • Able to connect to TTN
  • Ideally, multiple channels, i.e LoraWan compliant or nearly compliant

As for any other concerns, such as electricity, consider no limits.

Thanks

1 Like
4

I use ESP-8266 based single channel gateway with E19-868M1W RF module.

For Canada you probably would need 915 MHz version:

E19-915M30S

5

I asked because you seemed to be contemplating adding a low noise amplifier, and unless you add additional RF switching circuitry (not trivial) the LNA wouild need to be on a receive only channel.

Remember that LoRa already operates at well below noise level so low noise amplifiers do not operate in the same beneficial way as thay do in FSK above noise level systems.

6

If Lorawan is your goal, this is what you have to do

  • Use multiple “standard power” gateways geographically positioned for signal coverage (up on mountains and in dips).
  • Stick within the power limit and put the antenna of each gateway up high
  • Ensure that each gateway has access to an Internet connection (by line or GPRS)

No other way round it - there just too many reasons why this is what it is.

7

:thinking:I guess the problem comes when the internet backhaul point (GW location or reasonable proximity if using say Wi-fi or cellular GW link) is simply too far from where the sensor needs to be (and any deployed ‘standard’ GFW’s) given lack of viable LoRa(WAN!) repeaters then ‘maximizing’ LoRa range only real option…and if Canada indeed allows 1W EIRP Tx then that may be option…wrt achieving that range/sensitivity putting PA in play for TX path poss option as as stated earlier LNA in RX path less effective given LoRa sub-noise performance already, but should still help. I recall one of the recent GW/Concentrator boards for use with RPi et al had separate TX & RX paths allowing easier addition to implementation before we nudged in direction of converged path and use of RF switch. Also given potential for true bi-di comms with LoRa any options improving at GW need to be echoed at Node if link isnt to then become asymmetric unless system is purely bubble up, pre-joined before deployment, with no downlink/ack/confirm at extreme range required…

8

If uplink only then suggest concentrate on boosting node (if supply can sustain) vs looking at 1W GW…with higher gain ant used to improve local GW sensitivity…flattening of antenna effectiveness/focus not an issue if looking at extreme range vs local to GW as looking at/close to horizon?

9

A good general principle is to limit the power to the power that you actully need to use.

Using standard power levels of 25dBm for your gateway and with the 6dBi antenna on top of a 116’ mast, what range do you get for the nodes ?