Table of Contents:

1. Introduction

1.1 What is MDS200-NB NB-IoT Microwave Radar distance Sensor

The Dragino MDS200-NB is a NB-IoT Microwave Radar distance Sensor for Internet of Things solution. It uses 24Ghz Microwave to detect the distance between sensor and diferent objects. Diferent from ultrosonic or Lidar measurement. Microwave Radar is more reliable for condensation / dusty environment. It can sense correct distance even there is water or think dust on top of the sensor.

The MDS200-NB can be applied to scenarios such as horizontal distance measurement, parking management system, object proximity and presence detection, intelligent trash can management system, robot obstacle avoidance, automatic control, sewer, etc.

MDS200-NB can measure two distances: the closest object and next object behind the closest one.

MDS200-NB supports Alarm Feature, user can set the MDS200-NB to uplink data in a short interval when the distance is out of confgured range.

MDS200-NB supports different uplink methods including MQTT, MQTTs, UDP & TCP for different application requirement, and support uplinks to various IoT Servers.

MDS200-NB supports BLE configure and OTA update which make user easy to use.

MDS200-NB is powered by 8500mAh Li-SOCI2 battery, it is designed for long-term use up to several years.

MDS200-NB has optional built-in SIM card and default IoT server connection version. Which makes it works with simple configuration.


1.2 ​Features

  • NB-IoT Bands: B1/B2/B3/B4/B5/B8/B12/B13/B17/B18/B19/B20/B25/B28/B66/B70/B85 @H-FDD
  • Ultra-low power consumption
  • 24Ghz Microwave Radar for distance detection
  • Measure Range: 0.5 ~ 20m
  • Accuracy: ±0.1m
  • Resolution: 0.01m
  • Measurement Angle: horizontal 78° and vertical 23°
  • Multiply Sampling and one uplink
  • Support Bluetooth v5.1 remote configure and update firmware
  • Uplink on periodically
  • Downlink to change configure
  • 8500mAh Battery for long term use
  • Nano SIM card slot for NB-IoT SIM

1.3 Specification

Common DC Characteristics:

  • Supply Voltage: 2.5v ~ 3.6v
  • Operating Temperature: -40 ~ 85°C

Radar probe Spec:

  • Measuring Method: FMCW
  • Frequency: 24.000~24.500 GHz
  • Measurement output power: 6dBm
  • Measure Range : 0.5 ~ 20m
  • Accuracy: ±0.1m
  • Resolution: 0.01m
  • Measurement Angle : 78 degrees horizontal and 23 degrees vertical

NB-IoT Spec:

NB-IoT Module: BC660K-GL

Support Bands:

  • B1 @H-FDD: 2100MHz
  • B2 @H-FDD: 1900MHz
  • B3 @H-FDD: 1800MHz
  • B4 @H-FDD: 2100MHz
  • B5 @H-FDD: 860MHz
  • B8 @H-FDD: 900MHz
  • B12 @H-FDD: 720MHz
  • B13 @H-FDD: 740MHz
  • B17 @H-FDD: 730MHz
  • B18 @H-FDD: 870MHz
  • B19 @H-FDD: 870MHz
  • B20 @H-FDD: 790MHz
  • B25 @H-FDD: 1900MHz
  • B28 @H-FDD: 750MHz
  • B66 @H-FDD: 2000MHz
  • B70 @H-FDD: 2000MHz
  • B85 @H-FDD: 700MHz


  • Li/SOCI2 un-chargeable battery
  • Capacity: 8500mAh
  • Self Discharge: <1% / Year @ 25°C
  • Max continuously current: 130mA
  • Max boost current: 2A, 1 second

Power Consumption:

  • STOP Mode: 10uA @ 3.3v
  • Max transmit power: 350mA@3.3v

1.4 Applications

  • Horizontal distance measurement
  • Liquid level measurement
  • Parking management system
  • Object proximity and presence detection
  • Intelligent trash can management system
  • Robot obstacle avoidance
  • Automatic control
  • Sewer
  • Bottom water level monitoring

1.5 Installation

Sensor measure direction and angle is as below. When install the sensor, please make sure the sensor direct to object.



1.6 Sleep mode and working mode

Deep Sleep Mode: Sensor doesn't have any NB-IoT activate. This mode is used for storage and shipping to save battery life.

Working Mode: In this mode, Sensor will work as NB-IoT Sensor to Join NB-IoT network and send out sensor data to server. Between each sampling/tx/rx periodically, sensor will be in IDLE mode), in IDLE mode, sensor has the same power consumption as Deep Sleep mode.

1.7 Button & LEDs


Behavior on ACTFunctionAction
Pressing ACT between 1s < time < 3sSend an uplink

If sensor has already attached to NB-IoT network, sensor will send an uplink packet, blue led will blink once.
Meanwhile, BLE module will be active and user can connect via BLE to configure device.

Pressing ACT for more than 3sActive Device

Green led will fast blink 5 times, device will enter OTA mode for 3 seconds. And then start to  attach NB-IoT network.
Green led will solidly turn on for 5 seconds after joined in network.
Once sensor is active, BLE module will be active and user can connect via BLE to configure device, no matter if device attach NB-IoT network or not.

Fast press ACT 5 times.Deactivate DeviceRed led will solid on for 5 seconds. Means device is in Deep Sleep Mode.

Note: When the device is executing a program, the buttons may become invalid. It is best to press the buttons after the device has completed the program execution.

1.8 BLE connection

MDS200-NB support BLE remote configure and firmware update.

BLE can be used to configure the parameter of sensor or see the console output from sensor. BLE will be only activate on below case:

  • Press button to send an uplink
  • Press button to active device.
  • Device Power on or reset.

If there is no activity connection on BLE in 60 seconds, sensor will shut down BLE module to enter low power mode.

1.9 Pin Definitions , Switch & SIM Direction


1.9.1 Jumper JP2

Power on Device when put this jumper.

1.9.2 BOOT MODE / SW1

1) ISP: upgrade mode, device won't have any signal in this mode. but ready for upgrade firmware. LED won't work. Firmware won't run.

2) Flash: work mode, device starts to work and send out console output for further debug

1.9.3 Reset Button

Press to reboot the device.


1.9.4 SIM Card Direction

See this link. How to insert SIM Card.

1.10 Mechanical




2. Use MDS200-NB to communicate with IoT Server

2.1 Send data to IoT server via NB-IoT network

The MDS200-NB is equipped with a NB-IoT module, the pre-loaded firmware in MDS200-NB will get environment data from sensors and send the value to local NB-IoT network via the NB-IoT module.  The NB-IoT network will forward this value to IoT server via the protocol defined by MDS200-NB.

Below shows the network structure:


There are two version: -GE and -1D version of MDS200-NB.

GE Version: This version doesn't include SIM card or point to any IoT server. User needs to use AT Commands to configure below two steps to set MDS200-NB send data to IoT server.

  • Install NB-IoT SIM card and configure APN. See instruction of Attach Network.

Below shows result of different server as a glance.

ServersDash BoardComments




General UDPRaw Payload. Need Developer to design Dash Board 
General MQTTRaw Payload. Need Developer to design Dash Board 





1D Version: This version has 1NCE SIM card pre-installed and configure to send value to DataCake. User Just need to select the sensor type in DataCake and Activate MDS200-NB and user will be able to see data in DataCake. See here for DataCake Config Instruction.

2.2 ​Payload Types

To meet different server requirement, MDS200-NB supports different payload type.


User can specify the payload type when choose the connection protocol. Example:

AT+PRO=2,0            // Use UDP Connection & hex Payload

AT+PRO=2,5            // Use UDP Connection & Json Payload

AT+PRO=3,5            // Use MQTT Connection & Json Payload

2.2.1 General Json Format(Type=5)

This is the General Json Format. As below:

{"IMEI":"866207058378443","Model":"MDS200-NB","distance1":77,"distance2":77,"battery":3.56,"signal":25,"1":{61441,61441,2023/10/18 06:10:23},"2":{61441,61441,2023/10/18 06:07:24},"3":{61441,61441,2023/10/18 06:04:24},"4":{61441,61441,2023/10/18 06:01:24},"5":{61441,61441,2023/10/18 05:58:24},"6":{61441,61441,2023/10/18 05:55:24},"7":{61441,61441,2023/10/18 05:52:24},"8":{61441,61441,2023/10/18 05:49:24}}


Notice, from above payload:

  • Distance1,Distance2,Battery & Signal are the value at uplink time.
  • Json entry 1 ~ 8 are the last 1 ~ 8 sampling data as specify by AT+NOUD=8  Command. Each entry includes (from left to right): Distance1,Distance2,Sampling time.

2.2.2 HEX format Payload(Type=0)

This is the HEX Format. As below:



If we use the MQTT client to subscribe to this MQTT topic, we can see the following information when the NB sensor uplink data.



These bytes include the hardware and software version.

Higher byte: Specify Sensor Model: 0x0e for MDS200-NB

Lower byte: Specify the software version: 0x64=100, means firmware version 1.0.0

BAT (Battery Info):

Ex1: 0x0DD2 = 3538mV

Signal Strength:

NB-IoT Network signal Strength.

Ex1: 0x15 = 21

0        -113dBm or less

1        -111dBm

2...30 -109dBm... -53dBm

31      -51dBm or greater

99      Not known or not detectable


Distance between sensor probe to the first object. (unit: mm)

For example, if the data you get from the register is 0x0D 0xC6, the distance between the sensor and the measured object is 0DC6(H) = 3526 (D) = 3526 mm.

Notice: The distance has a special value :

0x3FFF: Reading Invalid (exceed the valid range of the probe) or Probe not detected.



Unit TimeStamp Example: 650d02ff(H) = 1695351551(D)

Put the decimal value into this link( to get the time.

2.2.3 ThingsBoard Payload(Type=3)

Type3 payload special design for ThingsBoard, it will also configure other default server to ThingsBoard.

{"IMEI": "866207058378443","Model": "MDS200-NB","distance1": 79,"distance2": 146,"battery": 3.56,"signal": 24}


2.2.4 ThingSpeak Payload(Type=1)

This payload meets ThingSpeak platform requirement. It includes only four fields. Form 1~4 are:

Distance1, Distance2,Battery & Signal. This payload type only valid for ThingsSpeak Platform.

As below:

field1=Distance 1 value&field2=Distance 2 value&field3=Battery value &field4=Signal value


2.3 Test Uplink and Change Update Interval

By default, Sensor will send uplinks every 2 hours & AT+NOUD=8

User can use below commands to change the uplink interval.

AT+TDC=600        // Set Update Interval to 600s

User can also push the button for more than 1 seconds to activate an uplink.

To save battery life, MDS200-NB will sample temperature & humidity data every 15 minutes and send one uplink every 2 hours. So each uplink it will include 8 stored data + 1 real-time data. They are defined by:

  • AT+TR=900        // The unit is seconds, and the default is to record data once every 900 seconds (15 minutes, the minimum can be set to 180 seconds)
  • AT+NOUD=8     //  The device uploads 8 sets of recorded data by default. Up to 32 sets of record data can be uploaded.

The diagram below explains the relationship between TR, NOUD, and TDC more clearly:


2.5 Trggier an uplink by external interrupt

MDS200-NB has an external trigger interrupt function. Users can use the PB15 pin to trigger the upload of data packets.

AT command:

  • AT+INTMOD         // Set the trigger interrupt mode
  • AT+INTMOD=0    // Disable Interrupt
  • AT+INTMOD=1    // Trigger by rising and falling edge
  • AT+INTMOD=2    // Trigger by falling edge
  • AT+INTMOD=3    // Trigger by rising edge

2.6 Set Transmit Interval Time(0x01)

Feature: Change nb-IoT End Node Transmit Interval.

AT Command: AT+TDC

Command ExampleFunctionResponse
AT+TDC=?Show current transmit Interval

the interval is 30000ms = 30s

AT+TDC=60000Set Transmit Interval

Set transmit interval to 60000ms = 60 seconds

Downlink Command: 0x01

Format: Command Code (0x01) followed by 3 bytes time value.

If the downlink payload=0100003C, it means set the END Node's Transmit Interval to 0x00003C=60(S), while type code is 01.

  • Example 1: Downlink Payload: 0100001E      //  Set Transmit Interval (TDC) = 30 seconds
  • Example 2: Downlink Payload: 0100003C     //  Set Transmit Interval (TDC) = 60 seconds

2.7 Set Alarm Transmit Interval Time(0x0D)

Feature: Change NB-IoT End Node Alarm Transmit Interval. Default Value: 1 minute

AT Command: AT+ATDC

Command ExampleFunctionResponse
AT+ATDC=?Show current alarm transmit Interval

the interval is 1 minute

AT+ATDC=1Set Alarm Transmit Interval

Set alarm transmit interval to 1 minute

Downlink Command: 0x0D

Format: Command Code (0x0D) followed by 1 byte for time value.

If the downlink payload=0D02, it means set the END Node's Alarm Transmit Interval to 2 minutes, while type code is 0D.

2.8 Set Alarm Distance (0xA2)

MDS200-NB supports Alarm Feature, when MDS200-NB detect the distance exceed the alarm settings, MDS200-NB will Enter Alarm Mode and use the ATDC interval (default is 1 minute) to uplink Distance value. Alarm mode will last for 60 uplinks (default 1 hour) and can be close by downlink command 0xA300.

Note: Alarm mode only valid for the Distance 1(the Closest Object)

User can set Alarm Distance to enable/disable Alarm Mode.


  • AA: Dec value for Alarm low threshold, BB: Dec value for Alarm high threshold
  • When 0xAA=0, and 0xBB≠0, Alarm trigger when higher than max
  • When 0xAA≠0, and 0xBB =0xFFFF, Alarm trigger when lower than min
  • When 0xAA≠0 and 0xBB≠0, Alarm trigger when higher than max or lower than min


   AT+ALARMC=100,200   // Alarm when < 100 or higher than 200.(Min:50cm, Max:2000cm)

Downlink Payload:

0x(A2 00 64 00 C8)            // Same as AT+ALARMC=100,200

2.9 Enter/Exit Alarm Mode (0xA3)

Feature: Enter/Exit Alarm mode:

AT Command: AT+ALARM=0(Exit Alarm Mode or AT+ALARM=1 (Enter Alarm Mode)

Downlink Command:

0xA3 00        // Exit Alarm Mode.  

0xA3 01        // Enter Alarm Mode.  Enter Alarm mode will use ATDC interval in the next 59 uplinks.

2.10 Set Interrupt Mode(0x06)

Feature, Set Interrupt mode for GPIO_EXIT.


Command ExampleFunctionResponse
AT+INTMOD=?Show current interrupt mode

the mode is 0 = No interruption


Set Transmit Interval
0. (Disable Interrupt),
1. (Trigger by rising and falling edge)
2. (Trigger by falling edge)
3. (Trigger by rising edge)


Downlink Command: 0x06

Format: Command Code (0x06) followed by 3 bytes.

This means that the interrupt mode of the end node is set to 0x000003=3 (rising edge trigger), and the type code is 06.

  • Example 1: Downlink Payload: 06000000           // Turn off interrupt mode

  • Example 2: Downlink Payload: 06000003           // Set the interrupt mode to rising edge trigger


3. Configure MDS200-NB

3.1 Configure Methods

MDS200-NB supports below configure method:

3.2 AT Commands Set

AT+<CMD>?           : Help on <CMD>

AT+<CMD>                      : Run <CMD>

AT+<CMD>=<value>      : Set the value

AT+<CMD>=?          : Get the value

General Commands       

AT                    : Attention        

AT?                  : Short Help      

ATZ                 : MCU Reset     

AT+TDC          : Application Data Transmission Interval

AT+CFG          : Print all configurations

AT+CFGMOD           : Working mode selection

AT+DEUI                  : Get or set the Device ID

AT+INTMOD            : Set the trigger interrupt mode

AT+5VT           : Set extend the time of 5V power   

AT+PRO          : Choose agreement

AT+RXDL        : Extend the sending and receiving time

AT+DNSCFG   : Get or Set DNS Server

AT+GETSENSORVALUE   : Returns the current sensor measurement

AT+NOUD  : Get or Set the number of data to be uploaded

AT+CDP     : Read or Clear cached data

AT+SHTEMP:   Get or Set alarm of temp

AT+SHHUM:   Get or Set alarm of moisture

AT+SERVADDR :   Server Address

UDP Management

AT+CFM  :    Upload confirmation mode (only valid for UDP)

MQTT Management

AT+CLIENT               : Get or Set MQTT client

AT+UNAME              : Get or Set MQTT Username

AT+PWD                  : Get or Set MQTT password

AT+PUBTOPIC          : Get or Set MQTT publish topic

AT+SUBTOPIC          : Get or Set MQTT subscription topic


AT+FDR              : Factory Data Reset

AT+PWORD        : Serial Access Password

AT+LDATA           : Get the last upload data

AT+CDP               : Read or Clear cached data

4. Battery & Power Consumption

MDS200-NB use ER26500 + SPC1520 battery pack. See below link for detail information about the battery info and how to replace.

Battery Info & Power Consumption Analyze .

5. Firmware update

User can change device firmware to::

  • Update with new features.
  • Fix bugs. 

Firmware and changelog can be downloaded from : Firmware download link

Methods to Update Firmware:

  • (Recommended way) OTA firmware update via BLE: Instruction.

6. FAQ

6.1 How can I access t BC660K-GL AT Commands?

User can access to BC660K-GL directly and send AT Commands.

See BC660K-GL AT Command set

7. Order Info

Part Number: MDS200-NB-XX


  • GE: General version ( Exclude SIM card)
  • 1D: with 1NCE* 10 years 500MB SIM card and Pre-configure to DataCake server

1NCE SIM Card NB-IoT network coverage: Austria, Belgium, Bulgaria, Croatia, Czech Republic, Denmark, Finland, Germany, Great Britain, Greece, Hungary, Ireland, Italy, Latvia, Malta, Netherlands, Norway, Puerto Rico, Russia, Slovak , Republic, Slovenia, Spain, Sweden, Switzerland, Taiwan, USA, US Virgin Islands

8. ​Packing Info

Package Includes:

  • MDS200-NB NB-IoT Microwave Radar distance sensor x 1
  • External antenna x 1

Dimension and weight:

  • Device Size: 13.0 x 5 x 4.5 cm
  • Device Weight: 150g
  • Package Size / pcs : 14.0 x 8x 5 cm
  • Weight / pcs : 180g

9. Support

  • Support is provided Monday to Friday, from 09:00 to 18:00 GMT+8. Due to different timezones we cannot offer live support. However, your questions will be answered as soon as possible in the before-mentioned schedule.
  • Provide as much information as possible regarding your enquiry (product models, accurately describe your problem and steps to replicate it etc) and send a mail to


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