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sarlen

Synthetic aperture length

    Description

    len = sarlen(v,t) returns the synthetic aperture length for a synthetic aperture radar given the sensor velocity and the synthetic aperture time.

    len = sarlen(r) returns the synthetic aperture length for the spotlight mode.

    len = sarlen(r,Name,Value) specifies additional options using the ConeAngle and CoherentIntegrationAngle name-value arguments.

    example

    len = sarlen(r,lambda,daz) returns the synthetic aperture length for the strip-map mode.

    example

    len = sarlen(r,lambda,daz,Name,Value) specifies additional options using the ConeAngle and AzimuthBroadening name-value arguments.

    Examples

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    Estimate the synthetic aperture length of a side-looking airborne strip-map synthetic aperture radar (SAR) operating in broadside at a wavelength of 0.05 m for a target range of 10 km. The radar antenna has an aperture length of 3 m in the azimuth dimension and an azimuth impulse broadening factor of 1.3.

    lambda = 0.05;
    Daz = 3;
    R = 10e3;
    azb = 1.3;

    Compute the synthetic aperture length.

    synlen = sarlen(R,lambda,Daz,'AzimuthBroadening',azb)
    synlen = 216.6667
    

    Input Arguments

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

    Data Types: double

    Synthetic aperture time in seconds, specified as a positive real scalar or a vector.

    Data Types: double

    Range from target to antenna in meters, specified as a positive real scalar or a vector.

    Data Types: double

    Radar wavelength in meters, specified as a positive real scalar or a vector.

    Data Types: double

    Antenna width in the azimuth direction 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

    Coherent integration angle in degrees, specified as a scalar in the range [0, 180]. This argument specifies the angle through which the target is viewed during the coherent processing aperture.

    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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    Synthetic aperture length, returned as a matrix.

    • If you specify v and t as input arguments, then len is a matrix with rows corresponding to the velocity values in v and columns corresponding to the aperture time values in t.

    • If you specify r as input for the spotlight mode, then len has the same dimensions as r.

    • If you specify r, lambda, and daz as input for the strip-map mode, then len is a matrix with rows corresponding to the radar range values in r and columns corresponding to the antenna azimuth dimension in daz.

    Extended Capabilities

    C/C++ Code Generation
    Generate C and C++ code using MATLAB® Coder™.

    Introduced in R2021a