Description The Unit GPS SMA is a compact GNSS global positioning and navigation unit using the ATGM336H navigation module and AT6668 chipset. With an active external SMA antenna, the Unit GPS SMA provides reliable satellite positioning for embedded devices that need accurate location data. Compared with earlier GPS units, the Unit GPS SMA supports multi-frequency and multi-system GNSS reception. It can receive GPS/QZSS, BD2, BD3, GLONASS, GALILEO, and QZSS signals, supporting either multi-system joint positioning or single-system positioning with stronger anti-interference performance in weak-signal areas. Features Unit GPS SMA design with ATGM336H navigation module and AT6668 chipset. Supports GPS/QZSS, BD2, BD3, GALILEO, and GLONASS satellite systems. Multi-frequency and multi-system reception with 50 channels. External active SMA antenna for more stable signal reception. Positioning accuracy under 1.5m (CEP50) and update rate up to 10Hz. UART communication at default 115200bps@8N1 with NMEA0183 4.1 protocol. Two LEGO-compatible holes and Grove PORT.C connection for M5Stack projects. Development support for Arduino, UIFlow, ESP-IDF, and related embedded workflows. Specifications Type GNSS global positioning and navigation unit with active external antenna GNSS chipset AT6668 Navigation module ATGM336H Supported satellite systems GPS/QZSS/BD2/BD3/GAL/GLO Frequency bands BDS B1I+B1C; GPS/QZSS/SBAS L1; GALILEO E1; GLONASS R1 Channels 50 channels Communication UART communication, default 115200bps@8N1 Positioning accuracy