Lora RFM95 Shield- 915MHZ
The Elecrow Lora Shield is a long range transceiver on a Arduino shield form factor and based on Open source library.The Lora Shield allows the user to send data and reach extremely long ranges at low data-rates.It provides ultra-long range spread spectrum communication and high interference immunity whilst minimising current consumption.
Using Hope RF's patented LoRa™ modulation technique the Lora Shield can achieve a sensitivity of over -148dBm using a low cost crystal and bill of materials. The high sensitivity combined with the integrated +20 dBm power amplifier yields industry leading link budget making it optimal for any application requiring range or robustness. LoRa™ also provides significant advantages in both blocking and selectivity over conventional modulation techniques, solving the traditional design compromise between range, interference immunity and energy consumption.
The RFM95 Shield is an inexpensive and versatile radio module. You can use it to send text or binary data between two or hundreds of modules. It’s perfect for building inexpensive long-range wireless networks for home automation, citizen science, and more.
- 168 dB maximum link budget.
- +20 dBm - 100 mW constant RF output vs.
- +14 dBm high efficiency PA.
- Programmable bit rate up to 300 kbps.
- High sensitivity: down to -148 dBm.
- Bullet-proof front end: IIP3 = -12.5 dBm.
- Excellent blocking immunity.
- Fully integrated synthesizer with a resolution of 61 Hz.
- FSK, GFSK, MSK, GMSK, LoRaTM and OOK modulation.
- Built-in bit synchronizer for clock recovery.
- Preamble detection.
- 127 dB Dynamic Range RSSI.
- Automatic RF Sense and CAD with ultra-fast AFC.
The RFM95 Shield is very easy to use.You need at least two of the shield and two Crowduino board. This program is used two this shield.
1.Download the RadioHead Library. Unzip and put it in the libraries file of Arduino IDE by the path: ..File/arduino IDE/Arduino/library/RadioHead.
Load and Modify the Code
We use two Lora Shields to transmit and receive signal,there are some project in the RadioHead Library,the operation is as follows:
Connect two Lora Shields with Arduino board and connect them to computer via the USB cable;
We used the Lora Shield+Arduino Mega328 as the server to transmit signal and the other Lora Shield+Aduino Mega328 as the client to receive signal here.
Connect the Lora Shield and Arduino,and connect them to computer.
Running the Sketches
In each serial monitor window, you’ll need to set the baud rate to 9600 and you can see them communicating well.