ADS-B has three more mature data links: UAT data link, Mode S1090MHz ES data link and VDL MODE4 data link, the domestic development of 1090MHz ES Data link, the link in the country has a relatively mature ground receiving equipment, In this paper, the design of a ADS-B target simulator based on 1090MHzES Data link is introduced in detail. The simulator can simulate multiple targets in three types of flight states. These three types of flight states include: horizontal and uniform linear flight, uniform acceleration of rising flight and uniform deceleration and descent flight. This design can simulate up to 200 ADS-B targets and can detect the reception performance of ADS-B devices well. The simulator is mainly composed of control system and launch System, in which the launch system is composed of RF front-end hair module and transmitting motherboard, the transmitting motherboard adopts ARM+FPGA hardware architecture, and the author is mainly responsible for the design of ARM module and the design of control system.

1.ADS-B SimulatorDevice overview

The signal simulation generator consists of transmitter and host computer software, and the reference DO-260B and D0-181E Protocol standard simulation produces four-channel ADS-B signal and A/C signal. Through the upper computer software configuration of each channel unit time to simulate the aircraft batch, transmission power, emission frequency, message information and other signal parameters, as well as the configuration of a specific batch of ADS-B between the channels, and finally through four RF channels synthesis, the formation of a specific degree of interweaving of the 5th channel Signal, Other channels can also be output separately.

2.ADS-B SimulatorDevice features

The signal analog generator has the following functions:

1) analog generation of four-channel signal, and signal power, signal frequency, emission rate adjustable;

2) Each channel has the ability to launch ADS-B message, Mode A/C message, and the transmission signal type can be adjusted;

3) can produce up to four-fold interwoven signal, and the degree of overlap can be adjusted;

4) The analog generated signal can be displayed on the map in real time.

3.ADS-B SimulatorMain technical indicators

Serial number Detecting content Technical Requirements

1 Emission frequency 1090±2MHz (customizable)

2 Frequency Minimum Step value 20KHz

3 Dynamic range of emission signals (50±2) dB

4 Transmit Maximum signal power (20±2) dBm

5 Minimum attenuation step value 0.5dB

6 Maximum attenuation value 50dB

7 Single channel maximum emission rate 2000 Bars/sec

8 Maximum interleaving Quantity 3/4 Heavy

9 Interlaced locations ADS-B 0-112us Adjustable

A/C 0-20.3μs Adjustable

10 Pulse width 0.4us-0.6us (customizable)

11 Pulse rising along, descending along Meet DO-260B and D0181E standards

12 GPS/BD location Source Support for internal and external positioning signals

13 Parameter configuration PC-Side software configuration