Hello,
We are using Raspberry Pi and SX1303 based gateway for our Lorawan Network, We are using a IN865 5.8dBi Fiberglass Antenna (Indian manufacturer), We are getting Very bad SNR values(all below -15).
Devices are within 1KM range
Is there any effect of SMA Connector and Antenna to SNR?
Is there anything we can do about this?
Thank You
Was the equipment tested before deployment?
You wrote that the antenna is for IN865, but are the devices (the node and gateway) meant for IN865 too?
What is the deployment environment like? LoRa has poor penetration power and its great range only exists with line of sight. Deployment in a city can be considered complicated.
This topic has been covered on this forum before. See here. Don’t assume your antenna is good, just because it was made for IN865 - test it OR purchase from a reputable manufacturer.
Real-life example: when I needed flexible antennas for US915, I took my sensor vendor’s advise and purchased 2J-antennas model (qty 40 of part # 2J5115P-915 was ~$200 + $90 S&H via DHL; comes to ~$7.25 each) instead of much cheaper antennas (~$1/each + ~$8 S&H; cost of $1.25/each) from ebay, but of questionable performance and worries.
I briefly considered purchasing a N1201SA , but decided that 1-man project had enough complexity already: I borrowed one briefly and while it was easy to use, it required ~1 hour for each antenna to connect, measure, modify/adjust, and then patch up external appearance to not look too crappy; realized that $7.25 each was actually a GREAT BARGAIN 
You state that all devices are within 1km. I have found LoRaWAN is viable alternative to costly runs of conduit (which cost kills many data-collection projects) and my facility is large, with many metal-sheeting partition walls, reinforced concrete, etc. Even so, all my sensors uplinks are received by all gateways, just with different SNR/RSSI; so much so that I disabled some of the installed gateways (red dots)
Example of one sensor’s uplink:
gatewayID:"*************7bc6"
* rssi:-105
* loRaSNR:-1.5
gatewayID:"**********474b"
* rssi:-106
* loRaSNR:-2.8
gatewayID:"***********3935"
* rssi:-72
* loRaSNR:12.2
gatewayID:"***********3da3"
* rssi:-75
* loRaSNR:12.8
Given particular sensor shown is in the “top” part of facility, you can deduce which gateways are which
