The JS-C8A is a compact, high-precision positioning module with multi-frequency, full-system support. It tracks BDS-2, BDS-3, GPS, GLONASS, Galileo, SBAS, and QZSS signals, and integrates onboard inertial navigation for enhanced accuracy. Featuring combined navigation algorithms, it is ideal for large-scale BeiDou applications and well-suited for intelligent driving, UAVs, robotics, and other advanced positioning fields.
Product Features
Small size and high precision
With inertial guidance
Multiple frequency points throughout the system, supporting Beijing III
With antenna detection
Multiple interfaces
Supports BDS, GPS, GLONASS, Galileo, SBAS and QZSS
Capable of suppressing potential narrowband and single-tone radio interference signals within the GNSS signal band
Mainstream package (22mm x17mm x 2.8mm±0.3mm), compact size, suitable forfor space sensitive applications
Supports NMEA 0183 protocol
Performance
| Category | Specification |
| Receive constellation frequency points | GPS: L1C/A, L2P, L2C BDS-2:B1I,B2I BDS-3:B1C,B2b GLONASS:G1,G2 Galileo:E1,E5b QZSS:L1C/A,L2C SBAS:L1C/A |
| Sensitivity | Tracking and Navigation : -155 dBm |
| Capture : -138 dBm | |
| First positioning time | Cold start : < 20 s |
| Warm start : <10 s (using RTC) | |
| RTK initialization : < 5 s (baseline length less than 10 km) | |
| Lost lock and recapture : < 1 s | |
| Accuracy | Single point positioning : H ≤ 1.5 m, V ≤ 3 m (1σ, PDOP ≤ 4) |
| RTK H ± (8 + 10-6 × D) mm | |
| V± (15 + 10-6 × D) mm | |
| D is the baseline length (unit: mm) | |
| Measurement accuracy | Pseudo range accuracy : ≤ 10 cm |
| Carrier phase accuracy : ≤ 1 mm | |
| Speed measurement accuracy | ≤ 0.02 m/s |
| Timing accuracy | 20 ns |
| Gyro | Measuring range : 250 °/s |
| Zero deviation in the whole process : 0.5 °/s | |
| Acceleration | Measuring range : 4 g |
| 20mg of zero deviation throughout the process | |
| Inertial navigation | The GNSS antenna signal loses lock for 3 seconds, and the accuracy remains cm level |
| The GNSS antenna signal loses lock for 10 seconds, and the accuracy remains m level | |
| Data rate | Measurement & positioning : 100Hz (optional) |
| RTK positioning : 20 Hz (optional) |
Pin Parameters
| Pin number | Pin name | I/O | describe |
| 1,3,12,14,32,37,41,48 | GND | G | land |
| 2 | RF_IN | I | GNSS signal input |
| 4 | ANT_DETECT | I | Antenna open circuit detection (default high level) |
| 5 | ANT_OFF | O | External low-noise amplifier enable (default high level) |
| 6 | ANT_SHORT_N | I | Antenna short circuit detection(Default high level) |
| 7 | VCC_RF | O | External low noise amplifier power supply |
| 8,9,10,11,13,15,16, 17,18,21,22,23,35, 38,39,40,46,47,50, 52,54 | RSV | - | reserved pin |
| 19 | GEOFENCE_STAT | O | Geofencing (user defined) |
| 20 | RTK_STAT | O | Flashing (high level is active when receiving RTCM data and performing RTK solution) |
| twenty four | COM3_RXD | I | UART 3 input |
| 25 | COM3_TXD | O | UART 3 output |
| 26 | COM2_RXD | I | UART 2 input |
| 27 | COM2_TXD | O | UART 2 output |
| 28 | SPI_CS | I/O | SPI_CS |
| 29 | SPI_CLK | I/O | SPI_CLK |
| 30 | SPI_MOSI | I | SPI_MOSI |
| 31 | SPI_MISO | O | SPI_MISO |
| 33,34 | VCC | P | Main power input |
| 36 | V_BCKP | P | Backup power input |
| 42 | COM1_TXD | O | UART 1 output |
| 43 | COM1_RXD | I | UART 1 input |
| 44 | I2C_SDA | I/O | I2C data |
| 45 | I2C_CLK | I/O | I2C clock |
| 49 | RST_N | I | reset |
| 51 | EVENT | I | External interrupt input |
| 53 | PPS | O | second pulse |
Product Application
Intelligent driving
Automotive applications
Maritime navigation, fleet management
Emergency Rescue
Drones
Personal protection
Car navigation and tracking
Protocols
| Protocol | Type |
| NMEA 0183 | GPGGA,GPGSV,GPGLL,GPGSA,GPGST,GPHDT,GPRMC,GPVTG,GPZDA |
| (CNB) binary format | custom binary |
| CMR(GPS) | CMROBS, SMRREF |
| RTCM2.X | RTCM1,RTCM3,RTCM9,RTCM1819,RTCM31,RTCM41,RTCM42 |
| RTCM3.X | 1004~1008,1012,1019,1020,1033,1042,1045/1046,1230,4078 MSM3~MSM7:1073~1077,1083~1087,1123~1127,1093~1097 |
