Questions tagged [lora]
LoRa (Long Range) is a wireless networking topology that focuses on low power and long range. It is frequently associated with M2M (machine-to-machine) and IoT (internet of things) networking technologies.
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About LoRa Remote Environmental Monitoring
I'm currently working on designing a wireless communication system for remote environmental monitoring, aiming to gather data from an open area approximately 1 kilometer away. The system needs to ...
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STM32WL55JC1 (lora module) is not sending or receiving
I am using 3 STM32WL55JC1. One for base station and the other two's for sensor node. Everything was fine but then I started UART communication between base station and ESP32. I started coding ESP32 so ...
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What's the best RF scheme and chip for my project?
I'm making a little scanning beacon gizmo. When a laser shines on it from ~40m away, it is supposed to transmit its ID and HIGH (1) to the laser controller ~40m away. Otherwise, transmit 0 or nothing. ...
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Circuitry around SMA for a LoRa module PCB (RX1276)
I am designing a PCB following the RX1276 reference design.
There are 6 reference designs presented on their website:
https://www.semtech.com/products/wireless-rf/lora-connect/sx1276
Pick any of the 6 ...
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How to measure 915 MHz LoRa RF power?
I'm having trouble measuring the RF power output of a nominally 20 dBm max (100 mW) LoRa board.
First I tried feeding the output into a cheap handheld spectrum analyzer through various attenuators. ...
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How to connect LoRa antenna and RP-SMA to U.FL to RFM69HCW?
I want to use this radio module and this antenna and this extender for my diy RC. Is this possible, and how would I connect the extender to my radio module? Can I cut the U.FL side and solder them ...
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How to add sequencer on STM32WL?
I am working with 3 STM32WL55JC modules. 1 used as receiver and the other 2 as transmitters.
The code:
...
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LoRa - Frequency Shift Chirp Modulation - chips in a symbol
I am trying to create a form of FSCM (frequency shift chirp modulation) based on LoRa principle just to learn from it and to obtain a deeper understanding.
What I do not get:
why is (or must be?) the ...
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Why the increase of the Spreading Factor (SF) by one, in the LoRa modulation, results in doubling of the transmission time of a symbol (T_symbol)?
Recently, I have been reading about the LoRa modulation and I am curious, why the symbol transmission time (T_symbol) doubles, if the Spreading Factor (SF) is increased by one.
The SF is equal to the ...
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STM32 LoRaWAN app only sends empty payload to the gateway
I'm developing a LoRaWAN app using STM32 Nucleo-WL55JC1 and Teseo-LIV3FL GNSS module. The example program of the SendTxData function works perfectly, but the ...
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RF design_output impedance of the SX1280 LoRa transceiver
I searched the datasheet of the Semtech SX1280, but I can't find the output impedance of the SX1280 (RFIO's pin). Where can I find it?
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Lack of understanding of LoRaWAN Fragmented Data Block Transport Decoding
I try to understand the Fragmented Data Block Transport decoding from this document (page 27).
Point 1 is clear. I need the same function as from the encoding process (see MatLab example code)
I don´...
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Antenna network design, 868 MHz Rainsun antenna
I want to add LoRa support to a PCB design of mine, and because I'm fabricating at JLCPCB, I am considering the following components (since they are well stocked):
DL-RFM95-868M LoRa module
AN1603-...
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Why does this RF PCB have small holes in the ground polygon?
I usually pay attention to RF PCBs.
This shape is like a hole, but it is not, the ground surface is used in the form.
What is the purpose of making these holes?
How can I make them easily with the ...
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How to capture enough energy from a 433 MHz RF signal to activate a transistor?
I have some battery-powered devices in a LoRa network with a custom gateway (my own PCBs) and was wondering if it's possible for the gateway to wake the other devices using a modulated 433 MHz signal (...
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How to use Lora Module (E32-868T30D) between 865-867MHZ
In India the allowed Lora frequency is between 865-867 MHZ and the module E32-868T30D is advertised for 868 MHZ. I am not sure if we can use the board within the specified range as mandated by Indian ...
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RN2483 very high TX current consumption
I am using a Microchip RN2483 LoRa module and I observed a very high TX current consumption, >400mA, sometimes 500mA. It doesn't happen systematically but when it does, it seems to affect every ...
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stm32 Lora UART communication
I have 2 lora module. I want to use one of them as receiver and the other one as transmitter. I can do this with 2 Arduino uno but I want to use one STM32 board as transmitter and Arduino uno board ...
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Differences between RF transceiver modules
I want to add a wireless M-BUS to the PCB I designed, but they are very expensive (about $30). While researching wireless M-BUS modules, a question came to my mind.
When I look at the datasheet of the ...
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I need help on identifying the value of a schematic symbol
I came across the schematic of RAK3272-Sip development board, but I couldn't identify the value of this inductor.
Here's a link that contains the full schematic.
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Is there any difference between antennas applications?
I'm thinking of adding LoRa module to the PCB I designed, and I chose an antenna.
NN02-201
The reason I chose this antenna is because I can easily find it in the country I live in.
However, LoRa is ...
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Sharing multiband antenna between ICs
I am working on a ultra low power project where portability and low weight is important. The circuit would have multiple ICs, that need to communicate over multiple frequencies:
Esp32 - WiFi/Bt 2.4 ...
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LoRa power level contradictions
I've got some LoRa boards that claim 20 dBm transmit power. They do indeed show ~100 mW output power on an old-school moving-coil RF wattmeter.
However, on a spectrum analyser with 20dB + 30dB ...
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Can SPI be used without implementing a modern MCU?
Is it possible to implement an SPI module such as a LoRa module, eg. RFM95, without the use of a [modern] microcontroller?
Edit: I have a hobby project that’s using a Z80 CPU.
The most available/...
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Matching network problem in CMX902 power amplifier with SX1261 [closed]
I'm trying to design a schematic of 3 Watt device using an SX1261 radio transceiver. For the power amplifier, I've chosen CMX902. I'm a little bit confused about the schematic I'm drawing, is it ...
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Is RFM9x LoRa Radio Module considered as LoRaWAN end-node?
I made the RFM96 LoRa Radio Module by adafruit communicate to each other. The next step I want to do is connect to it to a gateway, which is either the RAK7371 Developer Base or RAK2287 Concentrator ...
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Ebyte E32 RF module configuration problem
I designed a PCB with an STM32G474RET6. I used an Ebyte E32-433T30S module. I searched on web and read the datasheet. So, I got some info:
This Ebyte module needs to be configured before transmitting/...
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SX1262 Matching impedance
I want to build a LoRa node from SX1261 which works on the frequencies of 868Mhz and I found at the manufacturer the following assembly ms I did not find more details on the different passive ...
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How to send a large amount of data via LoRa
I'm trying to implement a LoRa communication between two devices (master and slave). I studied two modules that seem to be interesting RFM96WE and SX1276. From the ...
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Why have a filter before the LNA in LoRa boards?
I've looked through some Semtech reference board schematics and found one strange thing: they put SAW filters both before and after the LNA. For example here is part from a Semtech reference board ...
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How can LoRa transmit without interference even though SigFox also transmits on the same frequency?
LoRa and Sigfox both transmit over 868MHz ISM band. What solution does LoRa offer so that the contact continues to function without interference (Although Sigfox also transmits on the same frequency)? ...
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Understanding LORA XL1276-P01 Module
i'm trying to understand Lora Modem base on XL1276-P01 module. and this is the circuit I got from doing tracing on the module. what is the function of the block I circled?
I would love to understand ...
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Are SX1276 DIOx pins necessary?
This is about a SX1276 Semtech chip dev custom board:
For this project, is there anything missed when not connecting any of the DIOx pins to my microcontroller? I meant, in my project I have no pins ...
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Impedence matching required for very short PCB trace?
I have a custom PCB using 50 ohm impedance antennas for GPS (1.575 GHz), GSM (2.4 GHz), and LoRa (868 MHz). Currently using an impedance matched board with matching track widths of 6 mil. One track ...
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Ground plane placement in relation with LORA spring antenna
I am making a simple lora transciever and absolutely want to fit it on a single side dual layer 0.8mm thick pcb. Which makes impedance matching a bit tricky with 53mil traces...
Here the form factor ...
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Problems with track for LoRa RF
Following up on this question, I am using an RN2903 module with a U.FL connector (with an additional option for a through-hole wire antenna). My PCB looks like this:
I used this coplanar waveguide ...
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Arducam ESP32S Uno Pinout
I am trying to attempt to hook up an Adafruit Lora RFM9X to an Arducam ESP32-S Uno board. However, I am receiving the following error:
Failed to put device in Lora Mode RH_RF95_REG_01_OP_MODE: 0
I ...
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2.4GHz BLE and 900MHz LoRa coexistence
I am working on a new design for a simple BLE to LoRa bridge. I have a chip antenna for LoRa that covers 868-915MHz and I was following the Nordic reference design for the 2.4GHz BLE antenna. What ...
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ESP32 based device schematic review
I am building an IoT device with ESP32 WROOM as a host MCU.
I have already made two test PCB with it, and show somewhat unstable behavior.
The issues are;
It seems like USB-UART is unstable. ...
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Need Help Using A Radio Module (Gain Value)
I'm using the RFM98PW-443S2 RF module for a project. Microcontrollers I will be using this module with separately are: STM32F446RET6 and ATmega2560.
Datasheet link: https://www.hoperf.com/data/upload/...
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Trace impedance calculation in Altium for RF
I am routing the RF trace for a Microchip RN2903 LoRa module. The datasheet states the following:
I wanted to use Altium to calculate the width of the trace automatically, so that it had a 50 Ohm ...
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which antennas is better for 433 Mhz 30dbi LoRa module [closed]
I am searching a antenna for LoRa module. my first priority is distance. which is more long range, it is better for me. There are 3, 433Mhz 3dBi antennas. Can you help me which is best and why? if you ...
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CE marking of devices using pre-certified radio modules without antenna, just a 50 ohm RF port
I'm right now working on a project involving 2 radio modules, a SIM800F and a LoRa1276-C1-868.
The modules are already certified under the radio equipment directive. In the case of the LoRa module it ...
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How can I read the data of all nodes at the simultaneously with LoRa
assume that we have 4 e32 433T30d nodes we are measuring temp and sending to a center point. as a image atteached. I am using arduino.
I am using this library with arduino https://github.com/xreef/...
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What keeps frying my RF switches?
Short version: What might be breaking the first sensitive component connected to an ungrounded 14cm UHF dipole antenna mounted 30' above the ground? Could it be related to static electricity?
I have ...
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How to separate PCB antenna and SMA connector?
I am designing a prototype PCB for a Lora node.
It will have an SMA connector (J2) and a PCB antenna.
Switching RF connectors are not available in my area, so as an amateur enthusiast what is a good ...
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Is it possible that a 12V transformer is creating EM interference that's coupling onto a long antenna cable?
I have an Arduino Mega, Adafruit RFM96W 433MHz LoRa Transceiver Breakout and 2 Channel OptoCoupler Relay Module.
https://www.adafruit.com/product/3073
https://www.amazon.co.uk/SUNFOUNDER-2-Channel-...
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Data from my IoT node isn't displayed
I have a LoRa module called Adafruit Feather M0. I tried programming with Arduino in order to eventually display data. The data doesn't show up.
What I've done is that I've registered my LoRa device ...
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Lora sx1278 implementation by Arduino Uno
I'm implementing a Lora network, with two SX1278 modules and Arduino Uno. Lora is based on three classes. A , B and C, The question is : for change For example A to B, what should exactly change in ...
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Transmiting analog signal with lora
I want to transmit an analog signal over Frequency Modulation with a Lora RA 02 module. First thing I need to do is convert the analog signal from the audio source to digital, right?. But I had so ...
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