@cloolalang said in LoRa/RFM95 - Testing long range PHY settings - Findings:
w the SF 12 long payload messages pass!
I tested various SF and BW and coding rates, I decided on the following for the "long-range mode". Typical use will be point-point mode, or gateway to 2 or 3 nodes max, no repeaters. Horizontal polarised yagi antennas.
MY_RFM95_FREQUENCY 433237500ul (its 1MHz away from my co-located standard mode gateway frequency and other local ISM users).
RFM95_MODEM_CONFIGRUATION RFM95_BW62_5CR45SF4096 (Typical time-on-air is around 4000ms.
MY_RFM95_ATC_MODE_DISABLED (to reduce traffic).
How is testing going on this?
I'm interested to know what sort of distance you can cover, I'm planning on some long range sensors to be deployed on my farm. I'm not quite gettting the range I would like.
Here is the radio config in my current setup, but I will definitly look at some of the additional config that you have.
#define MY_RFM95_FREQUENCY (RFM95_868MHZ)
#define MY_RFM95_MAX_POWER_LEVEL_DBM (100)
#define MY_TRANSPORT_STATE_TIMEOUT_MS (3*1000ul)
#define RFM95_RETRY_TIMEOUT_MS (3000ul)
#define MY_RFM95_MODEM_CONFIGRUATION RFM95_BW125CR48SF4096
As a matter of interest has anyone used repeater nodes with these sort of long range setups. I'm talking about distances over a KM with no clear line of sight. I've managed to get simple comunications working over the required distance using simple transmitter and receiver sketches (provided by heltec, to demonstrate their Lora Node) sending "hello" packets
@mfalkvidd of course.
We have a MY_RFM69_FREQUENCY and a MY_RFM95_FREQUENCY. I think it would be easyer for the end user if we just got a MY_FREQUENCY.
Also, for future implementation of other LoRa modules (CubeCell, SX126x...) i think it would be good if we have a lora.h where we define structs like these, to define lora_header_t, lora_ack_t, lora_packet_t, lora_sequence_number ... as well as defines like LORA_MAX_PACKET_LEN, LORA_HEADER_LEN and so on.
It would ensure compatibility between lora modules and make maintaining easyer. (I know what I am talking about, I was looking for my error in the CubeCell driver for a half a day only finding that i defined the cubecell sequence number as a uint_8, not being compatible to the rfm95 uint16_t )
@cloolalang Actually, I'm tempted to try the SX1280. It's a lot more different: https://forum.mysensors.org/topic/11265/second-setup-choosing-a-radio/34?_=1595815545926
It looks as though a "good enough" test drive library may possibly already exist: https://github.com/StuartsProjects/SX12XX-LoRa
The same person range tested it and also did a thoughtful review: https://github.com/StuartsProjects/SX1280_Testing Paraphrasing, he says it lends itself to a more simplified programming style than the highly register centric approach of the SX127x's.
Spoiler: he proves a range of 40 kilometers transmitting at just 4dB. He estimates a range of 200 kilometers should be possible. Impressive for such a modest little module: