seed studio MR24BSD1 24GHz mmWave Module User Manual

: June 4, 2024
: seed studio

Table of Contents

seed studio MR24BSD1 24GHz mmWave Module
Overview
Functional disturbances
Functions in detail
Description of the agreement
Communication commands and parameter definitions
Description.
Read User Manual Online (PDF format)
Download This Manual (PDF format)

seed studio MR24BSD1 24GHz mmWave Module

seed studio-MR24BSD1-24GHz-mmWave-Module-

Overview

This document focuses on the use of the radar, the issues that need to be addressed at each stage to minimize design costs and increase product stability and improve the efficiency of project completion. From hardware circuit reference design, radar antenna and housing layout requirements, how to differentiate between interference and multi-functional standard UART protocol outputs.
The radar is a self-contained space sensing sensor, consisting of RF antenna, radar chip and high speed main frequency MCU together with a module that relies on a stable and flexible superior algorithm architecture core to solve the user’s various scenario detection needs, which can be equipped with a host computer or host computer to flexibly output detection status and data, meeting several groups of GPIOs for custom development.

Principle of operation

The radar transmits a millimetre wave signal in the 24G band, the measured target reflects the electromagnetic wave signal and demodulates the transmitted signal, which is then amplified, filtered and processed by ADC to obtain the echo demodulated signal data. The amplitude, frequency and phase of the echo signal are decoded in the MCU unit, which ultimately enables the measurement of target parameters (breathing, movement, micro-motion, etc.) and scene evaluation.

Hardware Design Considerations
The radar needs to have a rated supply voltage of 4.9 – 6V and a rated current requirement of 200mA or more input under normal operating conditions. The power supply must be designed for a supply ripple of ≤ 100mv.

The power supply can be designed with the following circuit in mind seed
studio-MR24BSD1-24GHz-mmWave-Module-fig-2

using the wiring diagram

Fig. 3 Schematic diagram of the radar module and peripheral connections

Antenna and housing layout requirements
PCBA: the radar needs to be kept ≥ 1mm higher than the other components Housing construction: need to maintain a distance of 2 – 5mm between the radar antenna face and the housing face
Housing detection surface: non-metallic housing, needs to be flat and straight to avoid curved surfaces which can affect the performance of the entire swept surface area. seed studio-MR24BSD1-24GHz-mmWave-Module-
fig-4

Fig. 4 Schematic diagram of the radar module and peripheral connections

Static Protection
Radar products have electrostatic sensitive circuitry and are susceptible to electrostatic hazards, therefore they need to be adequately protected from static electricity during transport, storage, work and handling. When handling radar sensors, please wear anti-static gloves if possible.

Functional disturbances

Unoccupied state, abnormal output occupied
In normal conditions, the radar will accurately determine the presence of a sitting or sleeping body and output information on falls, breathing, vital signs etc.

Radar scanning area is large, doorway, boarded wall next door movement is detected
Adjustment method: reduce radar sensitivity, radar provides scene setting B. Radar underneath is facing a running air conditioner or fan Adjustment: adjust the radar position so that it is not directly in front of the air conditioner or fan
Shifting objects caused by air conditioning winds
Adjustment method: cotton, non-metallic objects will not cause false alarms, metal objects need to be fixed
The radar is not fixed, vibration causes false alarms
Avoid supporting shaking and vibration
Occasional moving objects such as pets, birds, etc.
As the radar measures micro-movements, the sensitivity is very high and this interference cannot be excluded
Power supply interference, resulting in occasional false alarms
Try to keep the power supply current stable and reduce ripple

Manned status, abnormal output unoccupied
Radar determines the presence of a human body by sending and receiving electromagnetic waves. The closer you are to the radar, the more accurate it is.

Human body out of radar range
Radar scanning range with adjustment of mounting angle. Radar measurement range, in different environments with different electromagnetic wave reflection areas, the scanning area will vary slightly.
False output due to metal occlusion
Excessively thick desks and chairs, metal seats. It will block the electromagnetic wave penetration and cause misinterpretation. C. Differences in scanning angles
The radar does not scan the torso area. This can lead to false positives. D. Radar sensitivity is too low
The radar offers parameter adjustment to increase sensitivity for improvement.

Functions in detail

Function point descriptions

Functions	Status change time/function explanation

DP1: occupied/unoccupied

| No one to occupied, report within 0.5s Manned to unoccupied, no status output in 1-

2 minutes or so

DP2: Some people are stationary / Some people are active| Static dynamic switching, reporting within 0.5 seconds
DP3: Someone close to the device / someone moving away from the device /

someone moving without direction

|

Status output once every 2 seconds

Functions	Status change time/function explanation

DP4: Body movement amplitude parameter 0 – 100

| Data output once every 5 seconds Reference (description of output of body

motion amplitude parameters)

DP5: Sensitivity setting 1 – 10 steps

| Default scene mode, adapted to 10 positions of adjustment
DP6: Scene modes (bed, bathroom, hotel, bedroom, office, default mode)| Adapted to different scenarios according to the size of the area
DP7: No false alarm confirmation prompt|

DP8: Sleep parameter switch

| Off by default, sleep function only works when on
DP9: Bed entry/exit| Output status in 3S clock

DP10: Number of bed entries/exits

| Count the number of times you enter/leave bed in a day

DP11: Stationary dwell alarms

DP16: Breathing rate detection signal

| If there are factors such as distance, range and other effects, output breath-holding abnormalities, good signals, abnormal movements, abnormal states of shortness of

breath

DP17: Sleep scoring (optional, users can rate according to their own way)|

Combined day’s sleep rating

Description of the output of the body motion amplitude parameter

Body movement amplitude parameters

Description of the agreement

This protocol is used to communicate between a 24G millimeter wave sleep detection radar and a host computer.
This protocol outlines the radar workflow, provides a brief introduction to the interface protocol component architecture and gives the control commands and data required for the operation of the relevant radar, with the serial communication defined as follows.

Interface level: TTL
Baud rate: 9600bps
Stop bits: 1
Data bits: 8
Parity: None

Communication commands and parameter definitions

Definition and description of the frame structure

Frame structure definition
Description of the frame structure
- Start code: 1 Byte, fixed to 0X55.
- Data length: 2 Byte, low byte before, high byte after.
  Length = Data Length + Function Code + Address Code 1 + Address Code 2 + Data

Checksum.
```
* Function code: 1 Byte
* Read command: 0X01 Write command: 0X02  
```
Passive report command: 0X03
Active report command: 0X04
- Address code: Address code 1
  indicates the function classification, address code 2 indicates the specific function.
  See the description of address assignment and data information.
- Data: n Byte
- Checksum: 2 Byte, low byte before, high byte after.
  CRC16 checksum is used, see Appendix 1 for reference code.

Description of address assignment and data information

24G Bio-aware radar interface content

|

Function Code

| Address code 1|

Address code 2

|

Data

|

Notes

5

enquiries

| Sleep detection

parameter switch 0X0D

| Current sleep

detection

| | 0X05| | switch status

24G Bio-aware radar interface content

1

|

copy order 0x02

|

System parameters 0x04

|

Threshold gear 0x0C

|

Enumeration range1~10

| Corresponding to1 2 3 4 5 6

7 8 9 10 gears

(default 7) The higher the gear, the more

sensitive it is

2|

Scene setting 0x10

| Default mode 0x00|

3

| Area detection (top loading) 0x01|

4

| Bathroom (top mounted) 0x02|
5| Bedroom (top loading) 0x03|

6

Forced into unoccupied gear 0X12

24G Bio-aware radar interface content

9

| | Other functions

0X05

|

Reboot 0X04

| |

10

Start OTA upgrade 0X08

| 4byte Integer data (firmware package size)+ nbyte (software version

number)

|
| Upgrade package transfer

0X09

|

Packet Offset (4byte) + Packet (1024byte)

|
| End of upgrade information

0X0A

|

Fixed characters 0X0F

|
24G Bio-aware radar interface content|
---|---
1| Passive| | Device ID 0x01| 12 Byte data| |
reporting of

orders

|

Reporting module identification 0X01

24G Bio-aware radar interface content

1|

Passive reporting of orders 0x03

|

Upload Radar Info 0x03

|

Environment status 0x05

| Nobody 00 FF FF|
2| Static 01 00 FF
3| Movement 01 01 01

4

|

Signs parameters 0x06

| 4 Byte Float data (see Appendix 2)|

5

|

Reporting system parameters 0X04

|

Threshold gear 0X0C

| Current gear value (0X01~0X0a)|
6|

Scene setting 0x10

| Default mode 0x00|

7

| Area detection (top loading) 0x01|

8

| Bathroom (top mounted) 0x02|
9| Bedroom (top loading) 0x03|

10

Forced into unoccupied gear 0X12

13

| |

Other functions 0X05

| Sleep function switch 0x0D| Off 0x00|
---|---|---|---|---|---
On 0x01
14|

Start OTA upgrade 0X08

| Failed 0X00|
15| Success 0X01

16

| Upgrade package transfer 0X09|

Fixed characters 0X0F

|

24G Bio-aware radar interface content

1|

Proactive reporting of commands 0X04

|

Report radar information 0x03

|

Environment status 0x05

| Unoccupied 00 FF FF|

2

| Someone is stationary 01 00 FF

3

| U Some people exercise 01 01 01

4

| Motor signs parameters 0X06|

4Byte Float data

|

5

|

Approaching away state 0x07

|

Fixed characters 0x01

0x01

| None 0x01|
Approach 0x02
Far away 0x03
6|

Report other information 0X05

|

Heartbeat Pack 0X01

| Unoccupied 00 FF FF|

7

| Someone is stationary 01 00 FF|

8

| Some people exercise 01 01 01|

24G Bio-aware radar interface content

9

| | | Abnormal reset 0X02|

0X0F

| When the radar is restarted or re- powered, an abnormal reset command is reported before the initialisation process begins and a successful initialisation command is

reported.

Initialisation successful 0X0A

|

0X0F

| | | This means that the radar has been initialized

successfully.

| | | Start of normal operations.

24G Bio-aware radar interface content

1

|

Sleeping

Detection signal 0x04

| abnormality

0x01

No 0X02|
| | | Normal 0x00|

24G Bio-aware radar interface content

| | | |

Movement abnormalities 0X04

| When large movements of the person occur, abnormal movements are indicated, informing the user that large movements may affect the radar’s detection of

breathing

| | Shortness of breath abnormal 0X05|
2|

Scenario assessment 0x03

|

In/out of bed 0x07

None 0x02

| Sleep switch off shows none
4|

Sleep state assessment

7

|

None 0x03

| Sleep switch off shows none

8

|

Duration parameter 0x04

| Duration of wakefulness

0x01

|

4Byte integer data

|

Unit min

Length of light sleep 0x02| 4Byte integer data
Length of deep sleep

0x03

|

4Byte integer data

24G Bio-aware radar interface content

9

| | Sleep quality parameter

0x05

|

Sleep quality score 0x01

|

1Byte integer data

|
| | Heart rate parameter

0x06

|

Heart rate value 0x01

|

1Byte integer data

|

Unit times/min

Description.

The read/write command is for the upper computer to send commands to the radar.
The report command is for the radar to send information to the upper computer.
Fall sensitivity is 1~10, default is 4, the higher the level, the more sensitive it is
Human body sensitivity is 1~10 steps, default 7 steps, the higher the step, the more sensitive it is

Appendix 1: CRC check digit reference parsing codes

seed studio-MR24BSD1-24GHz-mmWave-Module-fig-8

seed studio-MR24BSD1-24GHz-mmWave-Module-fig-5

seed studio-MR24BSD1-24GHz-mmWave-Module-fig-6

seed studio-MR24BSD1-24GHz-mmWave-Module-fig-7

Appendix 2: Analysis codes for motor sign parameters

Historical version update notes

Revision

| Release Data|

Summary

---|---|---
V1.0_0212| 2020/02/12| First draft
V1.1_0319| 2021/03/19| Readjustment

V1.2_0628

|

2021/6/28

| Add Human sensitivity explained and fall sensitivity explained
V1.3_0906| 2021/9/06| Human sensitivity revised from 0-9 to 1-10
V1.5_0210| 2022/2/10| Add initialization success command protocol
V1.6_0221| 2-22/2/21| Adding a forced entry unmanned gear protocol

V1.7_0224

|

2022/2/24

| Addition of a “none” protocol in the entry and

exit states and a protocol for reporting heart rate data