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.
Large Size Thickened Felt Mat for Calligraphy, Wool Felt Pad for Brush Practice, Traditional Chinese Painting Desk Mat
$13.50
Creative Studio Sign Custom Door Plate Company Billboard LOGO Design Storefront Display
$119.00
Router Storage Box, Cable Organizer, WiFi Set-Top Box Stand, Gigabit Broadband Shelf with Wall Mount
$23.60
Baby Rattle with Teether for 0-6 Month Newborns, Sand Shaker and Hand Drum for Visual and Auditory Tracking
$10.50
Splicable Folding Food Warmer Partition Temperature Control Insulation Plate Hot Dish Plate Induction Cooker Plate Constant Temperature Heating Food Warmer Table Mat
$315.00
Marie's Kneaded Eraser Cotton for Sketching, Student-Use Blending Stump, Makeup Sponge for Art Students, Paper Blending Tool, Soft Absorbent Water-Drop Sponge Ball for Sketching
$8.33
Soft Cheese Processing Equipment, Lab-Type Cheese Stretching and Mixing Machine, Multi-Function Hot Water Stretching Unit
$210,210.00
Imported IKO Needle Roller Bearings TAF121912, 121915, 121916, 142212, 142216, 142220
$26.00
Portable Watercolor Sketchbook – 100% Cotton Mini Square Pocket Book for Travel, On-the-Go Sketching, Tear-Off Art Pages
$10.90
Dongguan Rotary Pad Printer Manufacturer - Fully Automatic 4-Station Pad Printer for Plastic, Metal, Text, Patterns, and Logos
$500.00
Custom Solid Wood Plaque, Antique-Style Wooden Sign with Engraving, Shop Signboard, Couplet, Carved Wood Plaque
$17.00
No-Drill Over-Toilet Storage Rack for Bathroom Wall Gap Behind Tank
$24.55
Upgraded Breakfast Food Warmer Display Cabinet - For Fried Chicken, Pies, Roasted Meat, with Crisp Preservation and Constant Temperature Control
$4,920.00
Butterfly Silicone Mold for Handmade Soap, Fondant, Chocolate, and Ice Cream
$14.00
Professional Music Services: Harmony Arrangement, Vocal Recording, Sheet Music, Mixing & Campus Orchestration
$20.00
Chunfei Grocery Store Yunan GR02 Gravel Bike Thru-Axle Disc Brake Light Load V Travel Many Rack Mounts
$6,445.00
![Pad Printing Silicone Head Mold with Blister Cover, Long Crystal Mold for Pad Printing Machines [Long Strip]](https://www.gosteppe.com/cache/small/product/270328/legacy-main-ca45adf23667d6b16fd9f3c4.webp)
Pad Printing Silicone Head Mold with Blister Cover, Long Crystal Mold for Pad Printing Machines [Long Strip]
$5.00
Remote-Controlled Automatic Fog Cannon for Xinjiang and Inner Mongolia Mines - Explosion-Proof, Anti-Freeze, Noise-Reducing Dust Suppression Sprayer for Coal Yards
$6,000.00
UV Glue for Bonding PET to Melamine Board, PC to Melamine Veneer, Invisible Adhesive for Glass Sliding Doors with UV Curing
$326.00
Mobile Welding Fume Purifier, Industrial Soldering Smoke Extractor, Welding Fume Collector and Exhaust Machine
$2,760.00
Upgraded Commercial Constant-Temperature Heated Display Cabinet for Fried Chicken, Meat Pies, and Breakfast Pastries
$5,510.00
2025 New Waterproof Swim Bag with Dry-Wet Separation - Lightweight Gym and Beach Tote for Men and Women
$14.80
4-Piece Canvas Stretching Tool Set with Wide-Jaw Pliers, Manual Staple Gun, and Starter Tool for Oil Painting Frames, Includes Tutorial
$10.20
Construction Anti-crack Steel Wire Mesh 4mm for Concrete Floors - Thickened Galvanized Iron Grid
$10.59
Japanese Dopamine Style Portable Retainer Case with Mirror - Storage Box for Invisible Aligners and Dentures
$16.00
Traditional Rattle Drum Toy for Infants - Old-Style Handheld Bell, Wave Shaker, and Sand Hammer for Newborns Aged 0-1 Year; Suitable for Boys and Girls
$6.90
Low-Temperature Plasma Oil Fume Purifier Electrostatic Ion Module Equipment Rubber Plastic Smoke Treatment Device
$1,600.00
Chunfei Grocery Store - Yun'an GR02 Gravel Bike, Thru-Axle, Disc Brake, Lightweight Touring with Multiple Rack Mounts
$7,977.00
Cashmir Blending Knife Replacement Head Set, Sketch Neony Blending Heads, Sponge Blending Heads, Breathing Cotton for Art Students
$4.34
Natural Amethyst, Rose Quartz, Clear Quartz, and Lemon Quartz Double-Pointed Tumbled Beads for DIY Bracelets, Necklaces, and Earrings
$1.70
![[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)
