Ai-Thinker Ra-02 LoRa Module, SX1278, 433MHz, SPI

The Ra-02 from Ai-Thinker is a compact LoRa module built around the Semtech SX1278 chip, widely used across hobby and IoT projects for its combination of genuinely long range and low power draw at the relatively modest data rates LoRa modulation operates at. Communication with a host microcontroller happens over SPI, giving faster, more flexible control than a simple UART-only module, at the cost of needing a few more wired connections.

Frequency range spans 410 to 525MHz, covering the common sub-GHz ISM bands used for LoRa in various regions, with a programmable bit rate up to 300kbps depending on the spreading factor and bandwidth settings chosen. Receive sensitivity reaches down to an impressive -148dBm, meaning the module can pick out extremely weak signals from background noise, a key factor behind LoRa's long-range reputation, and the manufacturer's claimed range for this module reaches up to 10km under favorable line-of-sight conditions.

Power requirements are notably low, running on just 2.5 to 3.7V input, making it a natural fit for battery-powered remote sensor nodes where every milliamp of standby draw matters. The module connects via an IPEX antenna connector rather than a fixed onboard antenna, letting builders choose an antenna suited to their specific range and form-factor needs. Physical size is compact at 17 x 16 x 3.3mm in an SMD-16 package, easy to integrate onto a custom carrier PCB.

Operating temperature is rated from -10 to 85C, giving reasonable headroom for outdoor-deployed sensor nodes. Builders working on remote environmental monitoring, agricultural sensor networks, asset tracking, or any project needing to transmit small amounts of data over genuinely long distances on minimal power will find the Ra-02 a proven, well-documented LoRa module from an established manufacturer.