丨 Product Introduction
1. Support full constellation multi frequency chip level RTK positioning.
2. Supports BDS, GPS, GLONASS, Galileo, QZSS, and SBAS.
3. The terminal supports Ntrip communication protocol and supports network base station services such as Chihiro location, CORS stations, and self built stations.
4. Can be used as a mobile station.
5. Adopt on-board standard 9-36V wide voltage input.
6. Adopt industrial grade 4G network communication module.
丨 Specification parameters
|
Specification parameters
|
|
GNSS module
|
1
|
working frequency
|
BDS: B1I B2I B3I B1C B2a B2b
GPS: L1 C/A L1C L2P (Y) L2C L5
GLONASS: L1 L2
Galileo: E1 E5a E5b E6
QZSS: L1 L2 L5 L6
|
|
2
|
Receiving channel
|
1408 channel
|
|
3
|
Single point positioning
(RMS)
|
Plane: 1.5m
|
|
Elevation: 2.5m
|
|
4
|
DGPS(RMS)
|
Plane: 0.4m+1ppm
|
|
Elevation: 0.8m+1ppm
|
|
5
|
RTK(RMS)
|
Flat: 0.008m+1ppm
|
|
Elevation: 0.015m+1ppm
|
|
6
|
Observation accuracy (RMS)
|
BDS
|
GPS
|
GLONASS
|
Galileo
|
|
7
|
B1I/B1C/L1C/L1 C/A/E1/G1 pseudorange
|
10cm
|
10cm
|
10cm
|
10cm
|
|
8
|
B1I/B1C/L1C/L1 C/A/E1/G1 carrier phase
|
1mm
|
1mm
|
1mm
|
1mm
|
|
9
|
B3I/L2P (Y)/L2C/G2 pseudorange
|
10cm
|
10cm
|
10cm
|
10cm
|
|
10
|
B3I/L2P(Y)/L2C/G2
|
1mm
|
1mm
|
1mm
|
1mm
|
|
11
|
carrier phase
|
10cm
|
10cm
|
10cm
|
10cm
|
|
12
|
B2I/B2a/B2b/L5/E5a/E5b pseudorange
|
1mm
|
1mm
|
1mm
|
1mm
|
|
13
|
Time accuracy (RMS)
|
10ns
|
|
14
|
Speed accuracy (RMS)
|
0.03 m/s
|
|
15
|
cold boot
|
＜10s
|
|
16
|
Initialization time
|
<5s (typical value)
|
|
17
|
Initialize reliability
|
＞ 99.9%
|
|
4G module
(network frequency band)
|
1
|
LTE FDD
|
B1/3/7/8/20/28
|
|
2
|
LTE TDD
|
B38/40/42/43
|
|
3
|
GSM/GPRS/EDGE
|
NA
|
|
4G module (propagation speed)
|
1
|
LTE FDD (Mbps)
|
10.3(DL)/5.1(UL)
|
|
2
|
LTE TDD (Mbps)
|
9.1(DL)/3.1(UL)
|
|
Bluetooth
module
|
1
|
Bluetooth version
|
2.0
|
|
2
|
Working frequency band
|
2.4G
|
|
3
|
Air speed
|
2Mbps
|
|
4
|
Reference distance
|
10m
|
|
Data format
|
1
|
Differential data
|
RTCM3.X
|
|
2
|
output format
|
NMEA-0183, RTCM3.X
|
|
3
|
Data update rate
|
1Hz-20Hz(default 1Hz)
|
|
Power supply
|
1
|
Voltage
|
DC +9V~36V
|
|
2
|
power waste
|
＜3W
|
|
3
|
Working current
|
≤145mA/12V
|
|
4
|
indicator light
|
1NET，1RTK，1BT
|
|
Physical
parameters
|
1
|
size
|
100mm*61.8mm*18.75mm
|
|
2
|
weight
|
180g
|
|
3
|
Shell material
|
aluminium
|
|
4
|
interface
|
SMA*2/8-core LEMO ports
|
|
Environmental
Specifications
|
1
|
working temperature
|
-30℃～＋70℃
|
|
2
|
Storage temperature
|
-40℃～＋85℃
|
|
3
|
humidity
|
95% condensation
|
|
4
|
Protection grade
|
IP65
|
|
5
|
Seismic resistance
|
Resist the impact of a 1-meter free fall
|
Table 1 M8 Interface Definition
|
Serial Number
|
Interface Name
|
Function Introduction
|
|
1
|
USB-D-
|
Parameter configuration USB interface D-
|
|
2
|
VCC
|
power input DC9-36V
|
|
3
|
NC
|
empty
|
|
4
|
NC
|
empty
|
|
5
|
RS232-TXD
|
RTK positioning output RS232-TXD
|
|
6
|
RS232-RXD
|
RTK positioning output RS232-RXD
|
|
7
|
USB-D+
|
Parameter configuration USB interface D+
|
|
8
|
GND
|
Grounding
|
|
Antenna interface
|
|
1
|
GNSS
|
Active positioning antenna, 3.3V, SMA interface
|
|
2
|
NET
|
4G antenna interface, SMA
|
Schematic diagram of connecting wires：
Display of the complete set of solutions：
Table 2 Complete Component Description
|
Number
|
Name
|
Quantity
|
Remarks
|
|
1
|
AK987EU terminal
|
1
|
|
|
2
|
Connecting line
|
1
|
M8 aviation head to type C; DC-DC power supply; DB9 female head
|
|
3
|
GNSS antenna
|
1
|
Full system full frequency antenna
|
|
4
|
Coaxial line
|
1
|
5mTNC to SMA, 50-3 wires
|
|
5
|
4G antenna
|
1
|
|
antenna parameters：
  |
|
Electrical
Characteristics
|
1
|
Frequency Range
|
GPS: L1, L2, L5
BDS: B1I, B2I, B3I, B2a, B2b
GLONASS: L1, L2, L3
Galileo: E1, E5b, E5a, E6
QZSS: L1, L2, L5, L6
IRNSS: L5
L-BAND
|
|
2
|
Output Standing Wave
|
≤2.0
|
|
3
|
Antenna Axial Ratio
|
≤3dB
|
|
4
|
Maximum Gain
|
5.5dBi
|
|
5
|
Phase Center
|
±2mm
|
|
6
|
Impedance
|
50Ω
|
|
7
|
Polarization Mode
|
RHCP
|
|
LNA
Specifications
|
1
|
LNA
|
L1:38±2dB
L2:38±2dB
|
|
2
|
VSWR
|
≤2.0
|
|
3
|
Noise Figure
|
≤1.8dB
|
|
4
|
In-band Flatness
|
1dB
|
|
5
|
Operating Voltage
|
3.3～12V
|
|
6
|
Operating Current
|
≤45 mA
|
|
7
|
Differential Transmission Delay
|
≤5ns
|
|
Structural Characteristics
|
1
|
Antenna Size
|
Φ159*61mm
|
|
2
|
Weight
|
≤380g
|
|
3
|
Connector Type
|
TNC
|
|
4
|
Thread Specification
|
Unified National Coarse (UNC) 5/8''×11 (Imperial)
|
|
5
|
Mounting Method
|
centering rod mounting
|
|
Environmental Conditions
|
1
|
Operating Temperature
|
-40℃～+85℃
|
|
2
|
Storage Temperature
|
-55℃～+85℃
|
|
3
|
Humidity
|
95% non-condensing
|
  |
|
Antenna
Characteristics
|
1
|
Operating Frequency
|
GPS: L1C/A, L1C, L2P, L2C, L5
BDS-2: B1I, B21, B31
BDS-3: B1I, B31, B1C, B2a, B2b
GLONASS: G1, G2, G3
Galileo: E1, E5b, E5a, E5AltBoC, E6c
QZSS: L1C/A, L2C, L5, L1C
SBAS: L1C/A
IRNSS: L5
|
|
2
|
Antenna Specifications
|
GPS, Bei Dou，GLONASS,GALILEO
|
|
3
|
Frequency Range
|
1165-1278/1559-1612MHz
|
|
4
|
V.S.W. R
|
≤2.0
|
|
5
|
Axial Ratio
|
Elevation angle 90 degrees: ≤3
Elevation angle 15 degrees: ≤5
|
|
6
|
Gain
|
Elevation angle 90 degrees: ≥6
Elevation angle 20 degrees: ≥0 (plane)
|
|
7
|
Front to back power
|
±60 degrees: ≥15dB
|
|
8
|
Phase Center (mm)
|
<2
|
|
9
|
Impendence
|
50Ω
|
|
10
|
Polarization
|
RHCP
|
|
LNA
|
1
|
LNA GAIN
|
38±2dB
|
|
2
|
V.S.W. R
|
＜2
|
|
3
|
Noise Figure
|
＜1.5
|
|
4
|
DC Voltage
|
3.3~18V
|
|
5
|
Current
|
＜35 mA
|
|
Mechanical
Structure
|
1
|
Component Name
|
SPEC
|
|
2
|
Antenna Connector
|
TNC / SMA
|
|
3
|
Antenna Dimensions
|
Φ120*38mm
|
|
4
|
weight
|
313.8g
|
|
5
|
PCB board
|
FR4
|
|
Environmental Characteristics
|
1
|
Operating Temperature
|
-40℃~+85℃, 10%~95% RH
|
|
2
|
Storage Temperature
|
-55℃~+100℃, 10%~95% RH
|
|
3
|
Vibration
|
Sine sweep @1.5mmAM
10~55Hz each Axis
|
|
picture
|
1
|
picture
|
|
|
|
Electrical
Characteristics
|
1
|
Operating Frequency
|
GPS: L1, L2, L5
BDS: B1I, B2I, B3I, B2a, B2b
GLONASS: L1, L2, L3
Galileo: E1, E5b, E5a, E6
QZSS: L1, L2, L5, L6
IRNSS: L5
|
GPS: L1, L2, L5
BDS: B1I, B2I, B3I, B2a, B2b
GLONASS: L1, L2, L3
Galileo: E1, E5b, E5a, E6
QZSS: L1, L2, L5, L6
IRNSS: L5
|
|
2
|
Frequency Range
|
1170-1278/1559-1612MHz
|
1170-1278/1559-1612MHz
|
|
3
|
V.S.W. R
|
≤2.0
|
≤2.0
|
|
4
|
Axial Ratio
|
Elevation at 90 degrees: ≤ 3,
Elevation at 15 degrees: ≤ 5
|
At elevation angle 90 degrees:
≤3, at elevation angle 15 degrees: ≤5
|
|
5
|
Gain
|
Elevation at 90 degrees: ≥ 6 dB,
Elevation at 20 degrees: ≥ 0 dB
|
At an elevation angle of 90 degrees:
≥6, at an elevation angle of 20 degrees: ≥0 plane
|
|
6
|
Phase Center
|
<2mm
|
<2
|
|
7
|
Impendence
|
50Ω
|
50Ω
|
|
8
|
Polarization
|
RHCP
|
RHCP
|
|
9
|
Out-of-Band Suppression
|
1268+100MHZ≥50db,
1170-100MHZ≥50db，
1602+100MHZ≥50db,
1561-100MHZ ≥50db.
|
1268+100MHZ≥50db,
1170-100MHZ≥50db，
1602+100MHZ≥50db,
1561-100MHZ ≥50db.
|
|
LNA
|
1
|
LNA GAIN
|
38±2dB
|
38±2dB
|
|
2
|
V.S.W. R
|
＜2
|
＜2
|
|
3
|
Noise Figure
|
＜2.0
|
＜2.0
|
|
4
|
DC Voltage
|
3.3~16V
|
3.3~16V
|
|
5
|
Current
|
＜35 mA
|
＜35 mA
|
|
Mechanical
Structure
|
1
|
Part Name
|
SPEC
|
SPEC
|
|
2
|
Antenna
|
FPC
|
FPC
|
|
3
|
Antenna Dimensions
|
Φ45.6*40mm
|
Φ62.1*25mm
|
|
4
|
Product Weight
|
25.8g
|
25.4g
|
|
5
|
Coaxial line
|
RG316 / RG1.13(customizable)
|
RG316 / RG1.13(customizable)
|
|
6
|
Line length
|
L=150mm / L=250mm(customizable)
|
L=150mm / L=250mm(customizable)
|
|
7
|
RF Output Interface
|
SMA-J / IPEX / MCX / MMCX(customizable)
|
SMA-J / IPEX / MCX / MMCX(customizable)
|
|
8
|
Antenna Housing
|
ABS+PC
|
ABS+PC
|
|
9
|
PCB Board
|
FR4
|
FR4
|
|
Environmental
Characteristics
|
1
|
Operating Temperature
|
-40℃~+85℃, 10%~95% RH
|
-40℃~+85℃, 10%~95% RH
|
|
2
|
Storage Temperature
|
-40℃~+85℃, 10%~95% RH
|
-40℃~+85℃, 10%~95% RH
|
|
3
|
Humidity
|
Sine sweep
@1.5mmAM 10~55Hz each Axis
|
Sine sweep
@1.5mmAM 10~55Hz each Axis
|
|
4
|
Vibration Resistance
|
95％ No-condensing
|
95％ No-condensing
|
AK181：
AK161：
Packaging and Delivery：
DALANG AK987EU 4G RTK High-Precision Positioning Terminal
The DALANG AK987EU is a high-precision GNSS receiver terminal that integrates 4G communication and full-constellation multi-frequency RTK positioning technology. Supporting BDS, GPS, GLONASS, Galileo, QZSS, and SBAS multi-system multi-frequency positioning, this terminal achieves centimeter-level precise positioning by receiving RTK differential base station data through 4G networks, making it an ideal solution for drone navigation, smart agriculture, and automotive high-precision positioning applications.
Full-Constellation Multi-Frequency RTK Positioning Engine
Equipped with a 1408-channel GNSS chip supporting multi-band signal reception including L1/L2/L5, it delivers RTK positioning accuracy of 0.8cm+1ppm horizontally and 1.5cm+1ppm vertically. By receiving differential data from services like Qianxun Position and CORS stations in real-time through 4G networks, it ensures stable and reliable centimeter-level positioning across various terrains.
Industrial-Grade 4G Communication and Power Design
Utilizing industrial-grade 4G communication modules supporting LTE FDD/TDD multi-band operation, it features 9-36V wide voltage input capability with power consumption below 3W. The built-in Bluetooth 2.0 module supports multiple data interfaces including RS232 and USB, ensuring long-term stable operation in demanding industrial environments.
Rugged Structure and Easy Integration
With an aluminum alloy housing measuring 100×61.8×18.75mm and weighing only 180g, it boasts IP65 protection rating. Equipped with SMA antenna interfaces and 8-pin LEMO ports, it operates in -30℃ to +70℃ wide temperature range, adapting to harsh outdoor environments.
Product Advantages
-
Full-System Multi-Frequency RTK Positioning
Supports all frequency points of six major satellite systems for global centimeter-level precision positioning
-
4G Network Differential Transmission
Industrial-grade 4G modules ensure stable differential data transmission, supporting Ntrip protocol
-
Wide Voltage Industrial Design
9-36V wide voltage input and low power consumption meet automotive and outdoor application requirements
-
Rugged Protective Structure
IP65 protection and wide-temperature design ensure reliable operation in harsh environments
Need a high-precision positioning terminal for your drone or agricultural system? DALANG AK987EU meets your precise positioning needs with full-constellation RTK technology!
About Us
DALANG is a dedicated manufacturer of high-performance GNSS modules and RTK positioning solutions, serving industries such as UAV navigation, precision agriculture, and geospatial mapping. With a clear focus on accuracy, reliability, and integration flexibility, we support both standard and custom applications across global markets. Our product lines are engineered to meet the evolving demands of real-time positioning with support for multiple GNSS constellations, including GPS, GLONASS, BDS, and Galileo.
Our production facility spans 2,500㎡ and includes advanced SMT lines, in-house R&D labs, and full functional testing for every unit shipped. With a team of 30+ GNSS engineers, we design and manufacture over 200,000 GNSS receivers and modules annually. Certified to ISO9001:2015, and compliant with CE and RoHS standards, we follow a strict quality assurance process from prototyping through mass production. We also provide firmware updates, system integration support, and full lifecycle product documentation.
Trusted by partners in over 30 countries, DALANG delivers fast, scalable manufacturing with personalized technical support. Our streamlined collaboration model—covering inquiry, consultation, prototyping, and delivery—ensures efficiency from first contact to deployment. Whether you're sourcing off-the-shelf GNSS hardware or launching a customized solution, DALANG is your dependable partner for accurate, cost-effective positioning systems.
FAQ
1. Who are we?
We are DALANG, a specialized manufacturer of GNSS modules and RTK positioning systems based in China, with a focus on high-precision solutions for UAVs, surveying, and smart agriculture.
2. How can we guarantee quality?
All products undergo strict multi-stage quality control, including SMT production, functional testing, and 100% final inspection. We are ISO9001:2015 certified and follow international compliance standards such as CE and RoHS.
3. What can you buy from us?
You can purchase GNSS receivers, RTK modules, base stations, antennas, flight control positioning systems, and other GNSS-related components and accessories.
4. Why should you buy from us not from other suppliers?
We combine strong in-house R&D, flexible OEM/ODM support, industrial-grade quality assurance, and fast global delivery. Our expertise in GNSS RTK ensures stable, accurate, and scalable solutions tailored to your specific use case.
5. What services can we provide?
We offer OEM/ODM customization, technical consulting, firmware support, prototyping, and global after-sales service. Our team works closely with international clients to ensure efficient communication and long-term support.
