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Doppler bandwidth due to cross-range platform motion



    dbwch = sarpointdopbw(v,azres) returns the Doppler bandwidth of a single scatterer (chirped) due to cross-range platform motion as the sensor illuminates the scatterer.

    dbwch = sarpointdopbw(v,azres,Name,Value) specifies additional options using name-value arguments. Options include the azimuth impulse broadening factor and the Doppler cone angle.


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    A side-looking airborne synthetic aperture radar (SAR) operates in broadside at a wavelength of 0.03 m with a sensor velocity of 100 m/s. The sensor illuminates a scatterer over a small cone angle interval having a cross-range resolution of 1 m and Doppler cone angle of 90 degrees. Compute the Doppler bandwidth of the received chirped signal.

    azres = 1;
    v = 100;

    Compute the Doppler bandwidth.

    bwchirp = sarpointdopbw(v,azres)
    bwchirp = 100

    Input Arguments

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    Sensor velocity in meters per second, specified as a positive real scalar or vector.

    Data Types: double

    Image azimuth or cross-range resolution in meters, specified as a positive real scalar or a vector.

    Data Types: double

    Name-Value Arguments

    Specify optional comma-separated pairs of Name,Value arguments. Name is the argument name and Value is the corresponding value. Name must appear inside quotes. You can specify several name and value pair arguments in any order as Name1,Value1,...,NameN,ValueN.

    Example: 'AzimuthBroadening',1.3,'ConeAngle',120

    Azimuth impulse broadening factor due to data weighting or windowing for sidelobe control, specified as a positive real scalar. This argument expresses the actual –3 dB mainlobe width with respect to the nominal width. Typical window functions like hamming and hann exhibit values in the range from 1 to 1.5.

    Data Types: double

    Doppler cone angle in degrees, specified as a scalar in the range [0, 180]. This argument identifies the direction toward the scene relative to the direction of motion of the array.

    Data Types: double

    Output Arguments

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    Doppler bandwidth of single scatterer (chirped) in hertz, returned as a matrix. The rows of dbwch correspond to the velocity values in v. The columns of dbwch correspond to the azimuth resolution values in azres.

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