Variant Matrix

The Quectel LC29H is a family of dual-band (L1+L5) GNSS modules sold under five variant designations, each targeting a different positioning use case.

Capability Matrix

Feature	AA	BA	CA	DA	BS
Dual-band L1+L5	Yes	Yes	Yes	Yes	Yes
Multi-GNSS (GPS/GLO/GAL/BDS/QZSS)	Yes	Yes	Yes	Yes	Yes
SBAS (WAAS, EGNOS, MSAS, GAGAN)	Yes	—	—	—	—
EASY (self-predicted ephemeris)	Yes	—	—	—	—
AGNSS online (EPO injection)	Yes	—	—	—	—
AGNSS offline (EASY prediction)	Yes	—	—	—	—
RTK rover	—	Yes	—	Yes	—
Dead reckoning (INS)	—	Yes	Yes	—	—
CAN bus interface	—	Yes	—	—	—
Wheel tick input	—	Yes	Yes	—	—
NTRIP client (via host)	—	Yes	Yes	—	—
RTCM3 output	—	—	—	Yes	Yes
Survey-in mode	—	—	—	—	Yes
Base station operation	—	—	—	—	Yes
Raw observation output	—	—	—	—	Yes
PAIR restart commands	Yes	—	—	Yes	—
PQTMGNSSRESTART	—	Yes	Yes	—	Yes
TTFF measurement	Yes	—	—	Yes	—

ModelInfo.json Reference

Extracted from QGNSS V1.8 ModelInfo.json. All LC29H variants default to 9600 baud and use the NMEA command protocol.

LC29HAA

{
  "name": "LC29HAA",
  "isNMEA_CMD": true,
  "Full": "$PAIR007*3D\r\n",
  "Warm": "$PAIR005*3F\r\n",
  "Hot": "$PAIR004*3E\r\n",
  "Cold": "$PAIR006*3C\r\n",
  "AGNSS": true, "AGNSS_OL": true,
  "NTRIP": true, "TTFF": true,
  "baudRate": "9600"
}

LC29HBA

{
  "name": "LC29HBA",
  "isNMEA_CMD": true,
  "Full": "", "Warm": "", "Hot": "", "Cold": "",
  "AGNSS": false, "AGNSS_OL": false,
  "NTRIP": true, "TTFF": false,
  "baudRate": "9600"
}

Note

Empty restart command strings indicate that PAIR003-007 are not available. Use PQTMGNSSRESTART instead with restart type 1 (hot), 2 (warm), 3 (cold), or 4 (full cold).

LC29HCA

{
  "name": "LC29HCA",
  "isNMEA_CMD": true,
  "Full": "", "Warm": "", "Hot": "", "Cold": "",
  "AGNSS": false, "AGNSS_OL": false,
  "NTRIP": true, "TTFF": false,
  "baudRate": "9600"
}

LC29HDA

{
  "name": "LC29HDA",
  "isNMEA_CMD": true,
  "Full": "$PAIR007*3D\r\n",
  "Warm": "$PAIR005*3F\r\n",
  "Hot": "$PAIR004*3E\r\n",
  "Cold": "$PAIR006*3C\r\n",
  "AGNSS": false, "AGNSS_OL": false,
  "NTRIP": true, "TTFF": true,
  "baudRate": "9600"
}

LC29HEA

{
  "name": "LC29HEA",
  "isNMEA_CMD": true,
  "Full": "", "Warm": "", "Hot": "", "Cold": "",
  "AGNSS": false, "AGNSS_OL": false,
  "NTRIP": true, "TTFF": false,
  "baudRate": "9600"
}

Present in ModelInfo.json but not listed in the Waveshare product line. Appears to be a basic NTRIP-capable variant with no PAIR restarts.

Restart Command Availability

The LC29H variants split into two groups for restart commands:

PAIR restart group (AA, AL, DA)

Command	Action	Framed
PAIR003	Cold start — clear all data	$PAIR003*3B\r\n
PAIR004	Hot start — retain all data	$PAIR004*3E\r\n
PAIR005	Warm start — clear ephemeris	$PAIR005*3F\r\n
PAIR006	Cold start — keep user config	$PAIR006*3C\r\n
PAIR007	Factory reset — clear everything	$PAIR007*3D\r\n

PQTM restart group (BA, CA, EA, BS)

Use $PQTMGNSSRESTART,<type>*CS where type is:

Type	Action
1	Hot restart
2	Warm restart
3	Cold restart
4	Full cold restart

Default Baud Rates

All LC29H variants ship from the factory at 9600 baud. The Waveshare sample code immediately reconfigures to 115200 baud on first connection.

Supported baud rates: 4800, 9600, 19200, 38400, 57600, 115200, 230400, 460800, 921600, 1500000, 3000000.

Set via $PAIR051,<rate>*CS or $PQTMCFGPORT,W,UART1,<rate>,NMEA|RTCM3,NMEA*CS.

Use Case Guide

AA Consumer Navigation and Asset Tracking

Best for general-purpose positioning where SBAS augmentation services are available (WAAS in North America, EGNOS in Europe, MSAS in Japan, GAGAN in India). EASY technology caches satellite ephemeris and predicts orbits for up to 3 days, reducing time-to-first-fix when the module powers on after a gap. AGNSS (EPO injection from MediaTek servers) further accelerates cold starts to approximately 5 seconds.

Typical applications: consumer GPS devices, fleet tracking, personal navigation, geocaching.

BA Vehicle Dead Reckoning with RTK

Combines inertial dead reckoning with RTK corrections for continuous centimeter-level positioning through GNSS-denied environments (tunnels, parking garages, dense urban canyons). Accepts vehicle sensor data via CAN bus or wheel tick pulse input.

Typical applications: autonomous vehicle prototyping, advanced driver assistance, precision agriculture with tunnel/bridge traversal, surveying vehicles.

CA Vehicle Dead Reckoning without RTK

Provides inertial dead reckoning using the same DR engine as the BA variant but without RTK correction capability. Maintains position continuity through GNSS outages using IMU and optional wheel tick input.

Typical applications: vehicle navigation through tunnels, dashcam with continuous position logging, fleet management in mixed urban/rural environments.

DA High-Precision RTK Rover

RTK-only variant optimized for fast convergence to centimeter-level accuracy. No dead reckoning. Fastest time to RTK fixed solution among the LC29H variants.

Typical applications: drone landing pads, precision agriculture (open field), surveying equipment, geofencing with centimeter accuracy.

BS RTK Base Station

Designed for fixed installation as a reference station. Outputs raw GNSS observations and RTCM3 correction messages. Supports survey-in mode to autonomously determine its position.

Typical applications: local RTK base station, feeding corrections to rtk2go or a private caster, CORS network contribution, precision agriculture reference point.

Variant Identification

The module can be identified at runtime by querying firmware version:

$PAIR021*38\r\n

Response includes model string (e.g., LC29HDANR). Alternatively:

$PQTMVERNO*58\r\n

Response includes firmware, hardware ID, and SDK version. The model string suffix indicates the variant: ...AA..., ...BA..., ...CA..., ...DA....