Foxtech LD-24 24GHz Millimeter-Wave Radar User manual

Brand: Foxtech

Model: LD-24 24GHz Millimeter-Wave Radar

Category: Measuring, testing & control

Type: User manual

Foxtech LD-24 24GHz Millimeter-Wave Radar is a compact and lightweight device designed for accurate altitude measurement in the height range of 0.2~50m. It adopts a unique antenna design and high-efficiency signal processing algorithms to achieve precise ranging capabilities. The radar operates at a frequency of 24.0 ~ 24.25GHz and has a transmission power of 20dBm, providing a reliable and stable signal for distance measurement.

LD-24 24GHz Millimeter-Wave

Radar Manual

Table of Contents

1. Product Overview ..................................................................................................... 1

2. Product Technical Parameters .................................................................................. 1

2.1 System Features ...........................................................................................1

2.2 Ranging Feature ........................................................................................... 2

2.3 Antenna Characteristics ............................................................................... 2

2.4 Product Pin Definition ...................................................................................2

2.5 Data Interface Protocol ................................................................................ 3

3.Joint Test of Ground Station....................................................................................... 3

3.1 Overall Functional Description ..................................................................... 5

3.2 Operating Environment ............................................................................... 5

4. Cautions ....................................................................................................................7

4.1 Transport , Storage and Use Precautions.......................................................7

4.2 Shell Design Parameters and Installation Requirements .............................. 8

5. Application Scenario .................................................................................................8

Disclaimer:

Please read the contents of this manual carefully to ensure that you can

use this product correctly and safely. Once used, it is deemed to be an

acknowledgement and acceptance of the contents of this statement. Please

strictly follow the manual to install and use this product . If there is

any damage or damage caused by incorrect use, Foxtech will not be

responsible for the corresponding loss and compensation. In line with the

principle of continuous improvement and continuous development, the

company reserves the right to modify and improve any product details

described in the document without prior notice. The content in this manual

is provided as of the time of manufacture, and unless otherwise required

by applicable law , no warranty of any kind, express or implied, is made

as to the accuracy, reliability, and content of this document. TO THE

MAXIMUM EXTENT PERMITTED BY APPLICABLE LAW, IN NO EVENT WILL THE COMPANY

AND ITS SUPPLIERS BE LIABLE FOR ANY SPECIAL, INCIDENTAL, INCIDENTAL , OR

CONSEQUENTIAL DAMAGES, HOWEVER CAUSED. This product is copyrighted by

Foxtech. Reproduction in any form is not permitted without permission. This

manual contains important information, please keep it for future reference.

1. Product Overview

LD-24 is a compact 24GHz millimeter-wave radar altimeter specially

designed for NAGA series multirotor. The size of the PCBA is only 45*45mm

and the weight is 6.5g.

We adopts unique antenna design, through high efficient signal

processing algorithm and high sensitive real-time signal processing method

based on time domain, frequency domain and phase, which can greatly reduce

the physical size of radar module and facilitate the integration of radar

module into the UAV fuselage, thus satisfying height determination demands

required by UAV.

The millimeter-wave radar can achieve accurate altitude measurement in

the height range of 0.2~50m (long time hovering is not recommended below

0.5m), which provides great convenience for UAV hovering and

terrain-following flight.

2. Product Technical Parameters

2.1 System Characteristics

Transmission Frequency：24.0 ~24.25GHz

Transmit Power (EIRP)：20dBm

Modulation Mode：FMCW

Hardware interface: UART-TTL

Size: 45*45*6mm （PCBA ）

Weight: 6.5g

Working voltage: 4~5.5V；Typical value: 5V ( independent power supply )

2.2 Ranging Characteristics

Distance Range：0.2m ~50m（over the ground

Working Current: 200~275mA； Typical Value: 220mA@5V

Storage Temperature: -40~85 ℃

Working Temperature: -40~80 ℃

）

Refresh Rate：50Hz

2.3 Antenna characteristics

Transmitting antenna

Elevation beamwidth：20°

Azimuth beamwidth：31°

Sidelobe Level: -19dB

Receiving antenna

Elevation beamwidth：31°

Azimuth beamwidth：20°

Sidelobe Level: -19dB

2.4 Product Pin Definition

Figure 1Product Pin Diagram

Table 1Pin Definition

Pin Definition Describe

1 VCC The Pin of positive

pole 3.5~5.5V

2 RX Data Receiving Pin

3 TX Data Sending

4 NC NA

5 NC NA

6 GND Negative Pole

Figure 2Dimensions ( unit: mm )

2.5 Data Interface Protocol

The radar adopts UART-TTL interface, using the preset default

transmission rate of 115200 bit/s , the start of the frame is indicated by the

space character of ASCII value for each datagram ( hexadecimal 0X2 0 )，at

the same time, the end of the frame is indicated by a line feed and carriage

return in the ASCII code value. LD24 radar sensor data frame refresh rate is

50Hz .

The radar uses an inquiry communication method. When the controller sends

an inquiry command once, the radar returns the current distance information

once. The query command sent by the controller is shown in Table 1.

Table 1: Controller Command List

Comment

'd' or 'D' Query the distance

information of the

radar

A complete data frame of UART-TTL communication has 7-8 bytes

according to the current measured distance of the radar. If the measured

distance is greater than 10m , use 5bytes to represent the distance information,

if it is less than 10m , use 4bytes to represent the distance information .

The data of each byte is character type, and the data frame is shown in Table

2below.

Table 2: Data Frame Format

Bytes Comment

1Frame header (frame header space)

4or 5 Distance Data

2Frame Tail

The starting sequence Frame header is a fixed value：0X20< space > , and

the ending sequence Frame Tail is a fixed value：

OX0D<CR> OX0A<LF> . An example of data analysis is shown in Table 3 :

= 0X0D 0X0A---------- <CR><LF>Frame Tail：

= 0X31 0X32 0X2E 0X33 0X34--------- 12.34Distance Data

= 0X20---------- <Space>Frame header

Eg 1：0X20 0X31 0X32 0X2E 0X33 0X34 0X0D 0X0A

Target Info Data Frame：

0X20 0X31 0X32 0X2E 0X33 0X34 0X0D 0X0A or 0X20 0X31 0X2E 0X33 0X34 0X0D 0X0A

两种情况下的数据解析：

Table 3: Data Parsing Example

The analysis is as follows:

Indicates that the distance information returned by the current radar sensor is

12.34m

Example 2 :0X20 0X31 0X2E 0X33 0X34 0X0D 0X0A

Frame header = 0X20 ---------< space >

Distance Data = 0X31 0X2E 0X33 0X34 -------- 1.34

Frame Tail :

The analysis is

as follows:

= 0X0D 0X0A -------- <CR><LF>

Indicates that the distance information returned by the current radar sensor is 1.34m

3. Joint Test of Ground Station

3.1 Overall Functional Description

The altimeter radar can display data in conjunction with the ground

station, which helps customers to more accurately debug and test the radar .

3.2 Operating Environment

The operation of 1.3.74 Mission planner software requires the

following software and hardware environments as shown in Table 4 :

Table 4Software and Hardware Environment Requirements

Category Low-end Configuration

Hardware

Requirements

CPU : 1.8GHz ; Memory: 512M ; Hard Disk: 40G

USB -to-serial cable (Note: Please make sure that the length

of the cable does not exceed 2m when upgrading the firmware )

Operating

System

support Windows 7 8 10 32 bit/64 bit

Test method is as follow: download and install the latest ground station

software from Ardupilot Website ( eg 1.3.74 Mision planner ).

https://firmware.ardupilot.org/Tools/MissionP lanner/

The testing tools or software are as follow:

LD-24 Radar

Notebook/PC

Independent Power Supply ( 5V power supply)

Mission Planner Software

Open Source Flight Controller ( if the firmware is missing, you can

download it from the Ardupilot website)

USB Cable / Datalink

LD-24 radar is connected to the open source flight control and power

input(the radar module should not be powered directly by the flight

control power supply, please ensure that it is powered by an independent

power supply), open the ground station Mission planner software and

connect to flight controller ( USB cable / datalink ). The software

operation steps are as follows: " Configuration / Debug " - " All Parameter

List "- configure the following parameters:

EK2_ALT_SOURCE=1

RNGFND1_TYPE=8

RNGFND1_ORIENT=25

SER1_BAUD=115200 (other SER ports can also be selected)

SER1_PROTOCOL=9

After configuration,operate as follow:

Click "Flight Data "to return to the main interface

Double-click the red box in Figure 3 to pop up the "Display This" interface

shown in Figure 3, and cancel other options, only check "sonarrange" ,

“sonar range”will be displayed here , which is the actual height of

the radar.

Figure 3

Figure 4

4. Cautions

4.1 Shipping, Storage and Use Precautions

It is necessary to fully do a good job of electrostatic protection during

the process of radar transportation, storage, working. When dealing with

non-integrated independent modules, users must pay attention: when the module

is taken out of the sealed anti-electrostatic package, it is necessary to

start the electrostatic protection work; do not touch or grab the surface of

the radar antenna and the connector pins, only touch its corners. It is

recommended to wear anti-electrostatic gloves whenever possible when handling all

radar sensors.

Do not wrap antennas with foil or partial metal parts; do not use CFK

sheet (conductive ) wrapping the antenna;

Do not spray the antenna structure with any kind of paint or varnish;

Do not let the plastic material come into direct contact with the antenna

structure ( which has the effect of a higher dielectric constant on

the resonant frequency of the patch ).

When the radar is installed, it is necessary to ensure that the module

is vertically downward, so as to ensure the accuracy of the detection

data.

When the radar is installed, the radar should be kept away from

electromagnetic interference sources such as motors and suspended metal

shells.

4.2 Shell design parameters and installation requirements

The radar shell will have a great influence on the actual effect of

the radar, which mainly depends on the shell material, thickness and the

distance between the inner surface of the radar module. LD-24 radar is

equipped with a wear-resistant, firm and beautiful shell structure. If you

need to customize the shell, our company can provide relevant consultation.

5. Application scenarios

The fixed altitude mode is the most important mode in the UAV flight

control, and the high-precision altimeter radar is the basis for the stable

flight of the fixed altitude mode. As we all know, fine-tuning the throttle

to ensure the lift and weight balance of the drone consumes a lot of energy for

the pilot, and the fixed altitude mode of the drone realized by the altimeter

radar can greatly reduce the difficulty of the pilot's operation. After the drone

enters the fixed altitude mode, the pilot can only control the flight direction

of the drone , which can greatly liberate the pilot and reduce the risk of

bombing. In addition, with the help of altimeter radar to achieve fixed height

hovering, you can get better photo effects. Not only that, the altimeter radar

also helps to achieve stable terrain-follow flight, improving the

applicability of UAVs in specific application scenarios such as line patrol.

Foxtech LD-24 24GHz Millimeter-Wave Radar User manual

Brand: Foxtech

Model: LD-24 24GHz Millimeter-Wave Radar

Category: Measuring, testing & control

Type: User manual

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