too many input arguments in my code!

% input parameters
c = 3e8;
f0 = 24.005e9;
lambda = c/f0;
bw = 240e6;
fs=2*bw;
Rmax = 100;
tm = 5.5*range2time(Rmax,c);
fb=4.3636e+07;

%radar setup
waveform = phased.FMCWWaveform('SweepTime',tm,'SweepBandwidth',bw,...
    'SampleRate',fs);

%target
tar_dist = 5;
tar_speed = 0;
tar_rcs = db2pow(min(10*log10(tar_dist)+5,20));
target = phased.RadarTarget('MeanRCS',tar_rcs,'PropagationSpeed',c,...
    'OperatingFrequency',f0);
tarmotion = phased.Platform('InitialPosition',[tar_dist;0;0],...
    'Velocity',[tar_speed;0;0]);    

%environment
channel = phased.FreeSpace('PropagationSpeed',c,...
    'OperatingFrequency',f0,'SampleRate',fs,'TwoWayPropagation',true);

antenna = patchMicrostrip('Length',75e-3, 'Width',37e-3,...
        'GroundPlaneLength',120e-3, 'GroundPlaneWidth',120e-3);
%show(antenna)


ant_aperture = 0.002775;                         % in square meter
ant_gain = aperture2gain(ant_aperture,lambda);  % in dB

tx_power = 0.85;                     % in watts
tx_gain = 9+ant_gain                         % in dB

rx_gain = 15+ant_gain;                         % in dB
rx_nf = 4.5;                                    % in dB

transmitter = phased.Transmitter('PeakPower',tx_power,'Gain',tx_gain);
receiver = phased.ReceiverPreamp('Gain',rx_gain,'NoiseFigure',rx_nf,...
    'SampleRate',fs);

radar_speed = 0;
radarmotion = phased.Platform('InitialPosition',[0;0;0],...
    'Velocity',[radar_speed;0;0]);
%simulation%
rng(2012);
Nsweep = 64;
xr = complex(zeros(fix(waveform.SampleRate*waveform.SweepTime,Nsweep)));

for m = 1:Nsweep
    % Update radar and target positions
    [radar_pos,radar_vel] = radarmotion(waveform.SweepTime);
    [tgt_pos,tgt_vel] = tarmotion(waveform.SweepTime);

    % Transmit FMCW waveform
    sig = waveform();
    txsig = transmitter(sig);

    % Propagate the signal and reflect off the target
    txsig = channel(txsig,radar_pos,tgt_pos,radar_vel,tgt_vel);
    txsig = target(txsig);

    % Dechirp the received radar return
    txsig = receiver(txsig);
    dechirpsig = dechirp(txsig,sig);

end

Dn = fix(fs/(2*fb));
for m = size(xr,2):-1:1
    xr_d(:,m) = decimate(xr(:,m),Dn,'FIR');
end

fs_d = fs/Dn;
fb_rng = rootmusic(pulsint(xr_d,'coherent'),1,fs_d);
rng_est = beat2range(fb_rng,sweep_slope,c)

i am getting these errors:

1. too many input arguments in : xr = complex(zeros(fix(waveform.SampleRate*waveform.SweepTime,Nsweep)));

2. Error using rootmusic,

Real signals require an even number p of complex sinusoids in: fb_rng = rootmusic(pulsint(xr_d,'coherent'),1,fs_d);

can anyone help?

Answer 1

[Steven Lord]

For your first question, let's split out the innermost function call on that line of code.

xr = complex(zeros(fix(waveform.SampleRate*waveform.SweepTime,Nsweep)));

innermost = fix(waveform.SampleRate*waveform.SweepTime,Nsweep);
xr = complex(zeros(innermost));

The fix function only accepts one input argument. You're trying to pass two into it. I believe you just have a misplaced parenthesis.

xr = complex(zeros(fix(waveform.SampleRate*waveform.SweepTime),Nsweep));

% or splitting into pieces
innermost = fix(waveform.SampleRate*waveform.SweepTime);
middle = zeros(innermost,Nsweep);
xr = complex(middle);

[M. Omer Farooq]

Thank you for you response.

can you explain the use of "fix" and how do we go without using it (as is in the original example: https://www.mathworks.com/help/phased/examples/automotive-adaptive-cruise-control-using-fmcw-technology.html)

and can you tell about rootmusic (error 2) too?

Thank you.