# Honglei Chen

### MathWorks

I am a developer on Phased Array System Toolbox at MathWorks

DISCLAIMER: Any advice or opinions posted here are my own, and in no way reflect that of MathWorks.

Professional Interests: Signal Processing, Array Processing, Radar, and Communication

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**Content Feed**

Trouble in codegen customized antenna pattern

I don't know how x is formed, but here is an example you can take a look, that generates the code. The main idea is to push patt...

3 months ago | 0

Adding Tapering and Time Delay

Unfortuantely at this point there is no straightforward way to combine the element taper with time steering. At this point, I th...

1 year ago | 0

| accepted

Antenna Pattern plot Phase

Looks like you are using Phased Array System Toolbox and it currently doesn't support 'phase' as a type. We will try to address ...

1 year ago | 0

| accepted

Wideband LOS channel block - propagate to multiple destinations

Could you share how you invoked the block? My guess is your signal is a single column vector while the block is expecting a matr...

1 year ago | 1

| accepted

What is the maths behind findpeaks function on matlab?

There is no specific name for the algorithm. Essentially it looks for points that is larger than the two adjacent points. Is the...

1 year ago | 0

Phased Array Toolbox Directivity Calculation

It would be helpful if you could share which textbook theory you are referring too. Directivity is often used interchangeablly w...

1 year ago | 0

Internal error in phased array toolbox applications.

This bug has been fixed in R2019b Update 2. If you get any update later than that, it should work properly. For more details, yo...

1 year ago | 0

| accepted

epsilon-neighborhood for polar coordinates

I'll explain how clusterDBSCAN works in this situation. In your case, range and angle will be two features so you can specify e...

1 year ago | 0

Backscatter Bycicle/Pedestrian Sampling Frequency

It seems that you are tring to simulate the radar echo. In that case, I don't think you can lift that constraint. In real applic...

1 year ago | 0

FMCW 24 GHz automotive Radar mmWaves simulation (Target Range&Speed Detection)

You can just randomly generate some range and speeds based on a trajectory. For example, phased.Platform can help generate some ...

1 year ago | 0

Angle Doppler response using FFT

I notice that you are using 128th range gate for plotting. Are you sure you have the correct target there? You can try to verif...

1 year ago | 0

| accepted

Electronic steering of clutter using phased.constantgamma clutter model

This is a good enhancement request, unfortunatly at this point the electronic scanning is not supported. We'll see if we can add...

1 year ago | 0

| accepted

Can I use phased.BackscatterPedestrian and phased.FMCWWaveform to simulate wideband echo, like fc=77GHz, BW=4GHz?

There is nothing prevents you to set the bandwidth to 4GHz. The only thing you need to be cautious is that with such a bandwidth...

1 year ago | 0

Phased Array System Toolbox: DOA with MVDREstimator using output data after Range-Doppler FFTs

To perform DOA estimation, the data input has to be across number of channels, i.e., number of elements in the array. On the oth...

1 year ago | 0

Simulation of range ambiguous clutter in phased array toolbox

phased.ConstantGammaClutter simulates clutter up to the horizon range. So it already builds the range ambuity in. HTH

1 year ago | 0

| accepted

Undefined function 'helperPolarizationView' for input arguments of type 'double'.

This is a helper function for the example, so you need to open that example from MATLAB. This will copy the supporting files int...

1 year ago | 0

Can phased.GSCBeamformer system Object run Frame by frame?

Those beamformers do main states but currently there isn't a way to export those states. Essentially, when you first run it usin...

1 year ago | 0

| accepted

What's the algorithm of the phased.rangeangle response

It depends on the system. In summary, if you use an FMCW waveform, you want to use FFT to do range processing. If you use a puls...

1 year ago | 0

Is ifft(fft(x).*fft(h)) faster or conv(x,h) ?

Time is not the best way to compare the two approaches. Rather, the best approach to describe is the computation complexity, i.e...

1 year ago | 0

The value returned from getNumInputsImpl method must be a constant value. But the Value is immutable

You said numInputs is nontunable, did you try to use Nontunable in the property defintion? Like properties (Nontunable) nu...

1 year ago | 0

Simulating Freespace power in Matlab

You can start with these reference pages https://www.mathworks.com/help/phased/signal-propagation.html? Go to Functions -> Sig...

1 year ago | 0

MUSIC algorithm ghost target in Matlab Radar Simulation Demo

The range angle image you mentioned in question is not a mirrored target, rather it's just an aliasing to the opposite side due ...

1 year ago | 0

About real time data processing in FMCW RADAR.

You may want to take a look at this example to get some idea on how to process real time data. https://www.mathworks.com/help/p...

1 year ago | 0

Matlab range and angle

I didn't quite understand what you mean by position = d.*t but rangeangle() support vectorization so you should be able to pa...

1 year ago | 0

MUSIC algorithm for direction of arrival

Generally speaking MUSIC belongs to subspace method. It doesn't really compare amplitude or phase, instead it takes advantage of...

1 year ago | 0

| accepted

Radar Doppler Signals for Car dataset!!

What is your requirement? Do you have any specific motion you want to cover? For a generic model, you can consider using many po...

1 year ago | 0

Collector for array formed of replicated subararrays

They do consider the gain at different angles. As to the input, you may want to check with your setting in array. Did you turn ...

1 year ago | 0

| accepted

matlab which filtfilt function handles filter objects

The filtfilt that handles a filter object will be a method on the filter object. For example, you can find filtfilt() method in ...

1 year ago | 1

| accepted

Building Radar Data Cube

For FMCW, after phased.ReceiverPreamp, that's the raw signal. You will need to mix it with the transmitted signal and then do an...

1 year ago | 0

How to get received signal at the carrier when use Phased Array ToolBox

Phased Array System Toolbox models the signal as a complex baseband representation. Normally a signal occupies certain bandwidth...

1 year ago | 0