Here are some of the more popular LoRa boards that are used to increase the functionality of different single-board computers.
LoRa (Long Range) is fast becoming the communication protocol of choice for IoT projects, as it provides the flexibility of low power and great range — perfect for applications such as wildlife tracking and environmental monitoring. According to the LoRa Alliance, there are more than 100 IoT LoRa-based networks operating around the globe, and the number continues to rise.
Those numbers are due in part by the maker communities and the affordability of project platforms, such as single-board computers and LoRa add-on boards. The LoRa boards allow makers to deploy their creations in genuinely remote areas without the need for constant servicing or battery replacement/recharging. As you can imagine, there are an equal amount of different LoRa add-on boards as there are SBCs — each with the same functionality in the communication protocol, but with various features. In this roundup, we will take a look at the more popular LoRa boards that are used to increase the functionality of different single-board computers.
Dragino LoRa GPS HAT
Why not get your Dragino LoRa GPS HAT (Source: Dragino)
Dragino’s LoRa GPS HAT for the Raspberry Pi is based on Semtech’s SX1276/SX1278 transceiver, which can handle 868 MHz/433 MHz/915 MHz frequencies with a 168 db maximum link budget. The list of features for this board is extensive, and includes +20 dBm -100 mW constant RF output vs. +14 dBm high-efficiency PA, has a programmable bit rate of up to 300 kbps, and has a low RX current of 10.3 mA (200 nA) register retention.
On the GPS side, the board offers a power acquisition of 25 mA, power tracking of 20 mA, a programmable bit rate up to 300 kbps, and an update rate of up to 10 MHz. It also features a timing accuracy of 1 PPS (out 10 ns), a velocity accuracy without aid @<0.1 m/s, an acceleration accuracy without aid @ 0.1 m/s², and a sensitivity acquisition of -148 dBm, among a host of others.
Dragino LoRa Shield
Dragion LoRa Shield (Source: Dragino)
Dragino also manufactures a LoRa Shield for the Arduino with similar specs as the Raspberry Pi version, only without the added GPS functionality. The feature set for the LoRa Shield includes a frequency band of 915 MHz/868 MHz/433 MHz, a programmable bit rate of up to 300 kbps, and a fully integrated synthesizer with a resolution of 61 Hz. The board also boasts FSK, GFSK, MSK, GMSK, LoRa and OOK modulation, automatic RF Sense and CAD with ultra-fast AFC, as well as a built-in temperature sensor and low battery indicator, among a myriad of other features.
Pi Supply micro:bit LoRa Node
Pi Supply micro:bit LoRa Node (Source: Pi Supply)
Pi Supply’s micro:bit LoRa Node is a great add-on board for the popular BBC development platform, and allows you to connect your projects to the Things Network. The LoRa Node comes packed with a RAKWireless RAK811 LoRa node module, which is designed around Semtech’s SX1276, and takes advantage of the full LoRaWAN stack. The Node also supports LoRaP2P modes, features a u.FL connector for external antennas, and can be configured to use either 868 MHz or 915 MHz, depending on where you live.
Adafruit LoRa Radio Bonnet
Adafruit LoRa Radio Bonnet (Source: Adafruit)
Adafruit’s LoRa Radio Bonnet for the Raspberry Pi is a great add-on board that packs a 128 X 32 OLED display that allows you to read status messages or may be used with integrated buttons to create custom user interfaces. Users can opt for either the 868 MHz or 915 MHz ISM bands utilizing SX1276 LoRa module with a 2 Km range. The Bonnet features +5 to +20 dBm with up to 100 mW power output capability and has a 100 mA peak during +20 dBm transmit, and 30 mA during active radio listening.
Seeed Grove LoRa Radio
Seeed Grove LoRa Radio (Source: Seeed)
Seeed’s Grove LoRa Radio can connect to any board with a modular, standardized connector, providing long-range wireless connectivity. The board packs an 868 MHz RFM95 ultra-long range transceiver which is based on the SX1276 and packs an ATMega168 for low-power applications. The Grove LoRa Radio offers 28 mA (@+20 dBm continuous transmit), 8.4 mA (@standby mode), and 20 mA (@receive mode, bandwidth 500kHz), and can use a simple wire antenna or high-gain antenna via a MHF connector, depending on the application.
SparkFun 1-Channel LoRa Gateway
While Sparkfun’s 1-Channel LoRa Gateway module is a stand-alone platform that uses an ESP32 WROOM microcontroller, it can also be used with an Arduino for extended capabilities. The module is designed around an RFM95W using the 868 MHZ or 915 MHz bands for long-range communication, while the ESP32 supplies Bluetooth and Wi-Fi capabilities. The module rolls at 170 mA when formatting SPIFFS in Gateway mode, 150 mA when searching for Wi-Fi networks in Gateway mode, 80 to 100 mA in steady operation of the Gateway, and just 70 mA when using LoRa.
Pi Supply IoT LoRa Gateway HAT
Pi supply IoT LoRa Gateway HAT (Source: Pi Supply)
Pi Supply is set to release their IoT LoRa Gateway HAT for the Raspberry Pi at some point this month, which features a RAKWireless, RAK833 mPCIe LoRa Gateway module based on Samtech’s SX1301. The HAT provides a fully LoRaWAN gateway capable of listening on 8-channels at the same time and can use either the 868 MHz or 915 MHz frequencies. The board is compatible with nearly every Raspberry Pi board (A+/B+/2B/3B/3B+/Zero/Zero W), as well as the Odroid C2 and ASUS Tinkerboard.
Udoit LoRa Shield
Udoit LoRa Shield (Source: Udoit}
Udoit’s LoRa Shield (AKA WIZIOT Board), is an excellent Arduino Uno add-on that packs an Aurel XTR 8LR100 half-duplex transceiver. It can use either the 868 MHz or 870 MHz bands, has a sensitivity of -138 dbm, and a range of up to 15 kilometers. What makes this board interesting, is it’s outfitted with 5X Grove connectors (2X digital, 2X analog, 1X I2 C), which allows you to attach a variety of Seeed modules, including relays, OLED displays, and a host of different sensor packages.
ElectronicTricks P10W LoRa Shield
ElectronicTricks PI0W LoRa Shield (Source: ElectronicTricks via Tindie)
ElectronicsTricks’ Raspberry PI0W LoRa Shield is another board that’s compatible with the TTN network (LoRaWAN), and can easily be implemented as a LoRa node or a 1-channel gateway, depending on the application. The Shield is outfitted with an RFM95 chip, can take advantage of 868 MHz/430 MHz/905 MHz frequencies, and is compatible with the Raspberry Pi Zero/W, 2, and 3. It also features an OLED display, 4X status LEDs, and an SMA connector for external antenna.
Cytron Technologies LoRa-RFM Shield
Cytron Technologies LoRa-RFM Shield (Source: Cytron Technologies via Tindie)
Cytron Technologies’ LoRa-RFM Shield for Arduino offers an RFM95W LoRa chip operating at 915 MHz, has a receiver sensitivity down to -146 dBm, and has an adjustable TX power strength of up to +14 dBm with high-efficiency PA. The Shield features a single SMA connector, u.FL connector, 3X Grove connectors for add-on modules, connection option for OLED displays, and stackable side headers for adding additional Shields.
Although the LoRa protocol, and subsequently the LoRaWAN network, has been around for over a decade, it’s still a fledgling technology. The cancellation of 2G and GPRS cellular networks in 2016/2017 created a void in the cellular spectrum which began to fill with low-powered IoT and mobile devices that could take advantage of long-range bi-direction communication, which led to broader deployment of the LoRaWAN network. As a result, LoRa-based add-on boards and modules have begun slowly entering the market, which is expected to grow larger as the technology becomes more affordable and widely available.