I get an error while executing Matlab Radar Tutorial

Hello,

I'm working on my bachelor thesis on automotive radar. I try to analyze the

Radar signal simulation and processing for automated driving tutorial:

https://www.mathworks.com/help/radar/ug/radar-signal-simulation-and-processing-for-automated-driving.html

The basic version works well, but when I change the scenario to include maltipath propagation (section Model a multipath channel at the end of the tutorial), it breaks.

I'm only changing these lines in the program:

% Create driving scenario
[scenario,egoCar,radarParams] = ...
    helperAutoDrivingRadarSigProc('Setup Scenario',c,fc)
% Initialize display for driving scenario example
helperAutoDrivingRadarSigProc('Initialize Display',egoCar,radarParams,...
    rxArray,fc,vMax,rangeMax);

into these:
% % Reset the driving scenario
[scenario,egoCar,radarParams,pointTgts] = ...
    helperAutoDrivingRadarSigProc('Setup Scenario',c,fc);
% 
% Run the simulation again, now using the two-ray channel model
metrics2Ray = helperAutoDrivingRadarSigProc('Two Ray Simulation',...
    c,fc,rangeMax,vMax,Nsweep,...           % Waveform parameters
    rngdopresp,beamformer,cfar,idxCFAR,clusterer,...           % Signal processing
    rngestimator,dopestimator,doaest,beamscan,tracker,...   % Estimation
    radar,sig);                      % Hardware models

And get the error:

Unrecognized field name "AngleOfDeparture".

Error in radarTransceiver/stepImpl (line 1442)

angd = [paths.AngleOfDeparture];

Error in test_radar_scenario (line 207)

rxsig = radar(tgtStruct,time+(m-1)*sweepTime);

I would be very glad, if somebody could help me with this problem :).

[Mann Baidi]

Hi Jakub,

The link which you shared is Temporarily Unavailable right now.Can you share an alternative link

[Jakub Dobosz]

The link should be OK now. You have copied the link with a period at the end and that's why it does not work.

Answer 1

[Pratik]

Hi Jakub,

In my understanding, you encounter an "unrecognized field name" error when you modify the lines in the program as indicated in the question. This assumption is made under the condition that no other sections of the code have been changed or commented out.

In the following section, the 'while' loop executes a simulation for the "Free Space Propagation Channel". The function "helperAutoDrivingRadarSigProc" runs a simulation loop when it gets the "Two Ray Simulation" argument. This function also resets all the parameters before the simulation. In the file “helperAutoDrivingRadarSigProc.m” on lines 418-434 many parameters have been reset, release and initialised.

“reset(obj)” resets the internal states and input properties of the System object to their initial values. “release(obj)” releases system resources such as memory, file handles, or hardware connections, and allows to change properties and input characteristics.

Thus, when this function is used for simulation, it runs fine. But when the next simulation starts the parameters have changed which is not compatible for the “Free space Propagation channel” simulation and it can cause error.

If you just need the simulation for “multipath propagation” the simulation loop can be commented or removed. However, if you need results for both scenarios simulate “multipath propagation” after “Free space propagation channel”.

Please refer to the following “reset” documentation for more information about resetting the internal states of system object:

https://www.mathworks.com/help/matlab/ref/resetsystemobject.html

Please refer to the following “release” documentation for more information about releasing system resources:

https://www.mathworks.com/help/matlab/ref/matlab.system.releasesystemobject.html

Hope this helps!