Engee documentation
Notebook

System model of a single-target single-position radar system

This model demonstrates the operation of a simple single target single radar system.

The special feature of the model is that the radar transmitter and receiver do not contain an antenna array. Thus, the antenna is equivalent to a simple isotropic element.

A sequence of rectangular pulses is used as a probing signal, which are amplified in the transmitter.

The signal is then propagated from the transmitter output to the target through free space. The reflected signal is received by the receiver.

The receiver amplifies the signal and also adds its own noise.

A matched filter is used as the processing unit, and propagation losses are compensated by adjusting the gain.

The final processing step is incoherent accumulation. The schematic of the model operation is shown in the figure below.

shem_1.jpg

Digital processing consists of the following elements:

shem_2.jpg

Next, let's connect libraries and files with functions that we will need in the process of processing the data written from the model and in the process of initialising the model parameters.

In [ ]: 
cd( @__DIR__ )
# Подгрузка функции инициализации модели
include( "initParamRadar.jl" );

Initialisation of model parameters.

In [ ]: 
paramRadar = calcParamRadar();

Based on the structural diagram, we developed the radar model shown in the figure below.

image_2.png

Let's run the model through a custom function.

In [ ]: 
modelName = "MonostaticRadar";
model = modelName in [m.name for m in engee.get_all_models()] ? engee.open( modelName ) : engee.load( "$(@__DIR__)/$(modelName).engee");
results =  engee.run( modelName,verbose=true );

Building...
Progress 2%
Progress 8%
Progress 17%
Progress 24%
Progress 30%
Progress 36%
Progress 42%
Progress 48%
Progress 54%
Progress 60%
Progress 65%
Progress 71%
Progress 77%
Progress 82%
Progress 88%
Progress 94%
Progress 100%
Progress 100%

Note: the signal on the receiver has temperature noise.

image.png

Let's open the results and plot the peak.

In [ ]: 
file_Rectangular_out = reduce(hcat, results["Y"].value)
R = paramRadar.metersPerSample .* (0:size(file_Rectangular_out, 1) - 1) .+ paramRadar.rangeOffset

plot( R,file_Rectangular_out[:,2]*1e6,label="",title="Корреляционный отклик на выходе модели",
    color=:red,lw=2,xlabel="Дальность,м",ylabel="Мощность,мкВт")
Out[0]:

Conclusion

We have examined the performance of a simple single position radar system. The final graph of the integrator output shows that the system found the peak, that is, it was able to detect an object at a distance of 2000 metres. This means that this radar method works correctly.

Blocks used in example