Description
Reviews
| Brand | - |
| Category | Robotics / STEM Teaching Tools / Sensors |
| Origin | - |
| Operating Frequency | 79 GHz |
| Detection Principle | Millimeter Wave Radar (FMCW) |
| Sensing Type | Non-Contact |
| Interface Protocol | UART / TTL |
| Supply Voltage | 5.0V DC ±5% |
| Operating Current | < 60 mA |
| Detection Range | 0 - 15 meters (adjustable) |
| Beam Angle | Horizontal 10°, Vertical 10° |
| Operating Temperature | -40°C to +85°C |
| Dimensions | 25mm x 25mm x 3mm |
Anonymous
Mar 31, 2026
Rating: 5/5
Reliable for harsh environments
Deployed three of these units in an outdoor agricultural setup. They have survived rain, dust, and temperature swings without issue. The non-contact nature means zero maintenance so far. Highly recommended for anyone building robust level sensing solutions.
Anonymous
Mar 23, 2026
Rating: 5/5
Solved our chemical tank monitoring issue
We needed a sensor that wouldn't react with mild acidic solutions. Since this radar module doesn't touch the liquid, it was the perfect solution. Installation was easy, and the readout is consistent. Will be ordering more for our other production lines.
Anonymous
Mar 20, 2026
Rating: 5/5
Compact and powerful
Impressed by the small form factor considering the performance. I am using this for a flood detection project near a riverbank. The ability to detect level changes without touching the water prevents biofouling. Documentation could be slightly more detailed, but the sample code helped get it running quickly.
Anonymous
Mar 18, 2026
Rating: 5/5
Excellent precision for industrial tanks
We integrated this LD7901B module into our prototype water storage monitoring system. The non-contact feature is a game changer as it eliminates corrosion issues common with probe sensors. Setup via UART was straightforward, and the data stability is impressive even with surface agitation.
Anonymous
Mar 17, 2026
Rating: 4/5
Good value for research projects
Purchased this for a university thesis on fluid dynamics monitoring. The accuracy is sufficient for our needs, and the price point is reasonable compared to industrial-grade alternatives. Just ensure your microcontroller can handle the UART baud rate correctly.
Anonymous
Mar 11, 2026
Rating: 4/5
Great module, needs careful calibration
The sensor works very well for detecting water levels in large containers. It took some time to tune the filtering parameters to ignore false positives from splashing, but once configured, it has been rock solid. The 79GHz frequency provides much better resolution than older 24GHz modules I've tested.
Q: What is the maximum update rate for the distance data?
A: The standard output refresh rate is configurable via the UART command set, typically ranging from 10Hz to 50Hz depending on the selected detection range and filtering settings. Please refer to the AT command manual for specific configuration instructions.
Q: Can this sensor detect water through a plastic tank wall?
A: Yes, the 79GHz millimeter wave radar can penetrate non-metallic materials like plastic or glass. However, the wall thickness and material density may affect signal strength, so we recommend testing with your specific tank material to ensure optimal range.
Q: Does foam on the water surface affect the reading accuracy?
A: Heavy foam can attenuate the radar signal slightly, potentially causing minor fluctuations in the reading. However, the LD7901B includes digital filtering algorithms that help stabilize the output. For thick foam layers, you may need to adjust the sensitivity thresholds.
Q: Is there a library available for Arduino or ESP32?
A: We provide a basic C-language demo code and communication protocol documentation on our GitHub repository. While there is no official pre-compiled Arduino library yet, many users have successfully created their own drivers based on our provided examples.
Q: What is the power consumption in sleep mode?
A: The module supports a low-power sleep mode which reduces current consumption to approximately 10µA. It can be woken up via a specific UART command or a hardware trigger pin, making it suitable for battery-operated applications.
Adjustable Over-Toilet Storage Rack for Bathroom Floor Standing Space Saving Organizer
$147.20
Flake Soy Wax & White Bees Wax Pellets – DIY Cup Candle Making Kit with Strawberry Scented Mold and Raw Materials
$5.34
Manufacturer Supply FF High-Speed Dispersing Kettle - Stainless Steel Reactor for Paint, Ink, and Chemical Mixing Equipment
$9,104.80
Mia Bouncy Sketch Blending Cotton Sponge Ball Paper Stump Water-Absorbent Sponge New Art Tool Washable Magic Cotton for Students
$4.80
Yucheng 1606 Fast-Drying Acrylic Adhesive - Odorless, Non-Whitening Glue for Acrylic Bonding
$21.20
Magnetic Storage Shelf Cute Building Block Magnetic Organizer Box Refrigerator Decorative Sticker Cling Film Holder Wall-Mounted Fridge Magnet
$3.80
Commercial Countertop Fried Chicken Warmer Cabinet Hamburger Egg Tart Heating Constant Temperature Box Multi-Function Insulated Display Case for Fried Foods
$620.00
Rectangular Silicone Mold for DIY Handmade Soap
$16.80
Leqin 495 Super Glue - 20g Transparent Fast-Drying Adhesive for Hard Plastics, Metal, Wood, PVC, and Rubber
$25.84
New Chinese Style Zen Calligraphy Felt Mat, Non-Slip Desk Pad for Traditional Writing Tools
$16.50
LB-8001 Inline Water Sampler - Mixed Water Sample Retention Instrument
$10,312.16
Mont Marte Children's Paint Brush Set - Toddler Tempera and Watercolor Brushes, Beginner Fan Brushes, Graffiti Tools
$7.00
Alumina Hollow Sphere Bricks, Castables, High-Temperature Mullite Bricks, High-Alumina Lightweight Insulating Bricks
$124.53
Natural Crystal Lemon Yellow Azeztulite Round Beads for DIY Jewelry Making, Bracelets, and Necklaces
$0.74
Fast Stair-Climbing Folding Hand Truck, Portable Shopping Cart for Groceries and Luggage
$304.08
Yonghe Hair Transplant: Shaved Method for Large-Area Top Density Enhancement - Unlimited Grafts by Director Team
$19,800.00
Long Rectangular Self-Watering White Planter for Narrow Window Sills and Balconies
$12.90
![[In Stock] Maihe BOXFUN Rilakkuma Watch Blind Box - Gulu Gulu Moment Series Wristwatch, Gift for Girls](https://www.gosteppe.com/cache/small/product/269930/legacy-main-81bb51a69f43ed5a98182a06.png)
[In Stock] Maihe BOXFUN Rilakkuma Watch Blind Box - Gulu Gulu Moment Series Wristwatch, Gift for Girls
$29.00
6-Cavity Tulip Flower Handmade Soap Mold - DIY Silicone Mold for Soap and Baking
$11.87
TILTA Video Transmission Heat Sink Cooling Fan Compatible with DJI Transmission
$298.75
CNC External Thread Tool Holder SER2020K16/2525M16, 22 Positive/Negative External Turning Lathe Bar
$15.92
Drive Board JINT-E1C for ABB ACS850 Inverter
$4,100.00
Retainer Storage Case - Portable Magnetic Box for Invisalign, Dentures, and Children's Braces
$17.80
High-Quality Natural Wood Pencils - Non-Toxic HB and 2B for Grades 1-2 Writing, Exams, Drawing, and Sketching
$4.02
Wen Zhengming Small Regular Script 'Caotang Shizhi, Xue Fu, Yue Fu' Close-Up Tracing Cards Calligraphy Copybook
$10.00
Inverter Power Board SINT4610C
$3,072.00
Freestanding Bathroom Toilet Storage Rack, Multi-Tier Organizer for Above-Toilet Space
$92.80
VP39-2/J30-18 Transmission Bearing Size 30X62X20 Original Japan Import
$402.00
Marie's Art Exam Sketch Blending Stump Set - Dual-Head Gray Surface Blending Pen, Full Kit with Soft-Tip Paper Stumps (2-Pack) for Professional Art Students
$5.80
G80 Manganese Steel Lifting Chain Rigging - Hooks, Links, and Rings for Crane Hoisting and Mold Handling
$96.00
![[Trial Pack] Xianlang Complete Cat Treat Sticks Meal Packs Main Course Cans Freeze-Dried Cat Food Sample Snacks Gift Set](https://www.gosteppe.com/cache/medium/product/208273/legacy-main-9ec245ebf781f65a434ba854.webp)
