helperTargetRCS.jl

squeeze(A) = reshape(A, filter(!=(1), size(A))...)

function plotting_sig(sig,mod_ang;title = "Отраженный сигнал от конуса")

    plot(mag2db(abs.(sig)),lab="Отраженный сигнал",lw=2)
    xlabel!("Отсчеты")
    ylabel!("Отраженный сигнал, дБ")
    title!(title)
    plot!(twinx(),mod_ang,lab=["азимутальный угол" "угол места"],
        color=["red" "green"],ticks=nothing,guidefontcolor="white",ls= :dash,
        legend_position = :outertopright,formatter=(_...) -> "")
end

function calc_model_turn(;lin_ang=[0,40],amp_rng=[20,45],num_turn=4)
    # модель вращения тела
    return (LinRange(lin_ang[1],lin_ang[2],N))' .+ ((LinRange(amp_rng[1],amp_rng[2],N)) .*sin.(LinRange(0,num_turn*2π,N)))' 
end

function rcscylinder(r1,r2,H,c,fc,az = -180:180,el = -90:90)

    r1 > 0 || throw(ArgumentError("R1 must be positive scalar"))
    r2 > 0 || throw(ArgumentError("R2 must be positive scalar"))
    H > 0 || throw(ArgumentError("H must be positive scalar"))
    c > 0 || throw(ArgumentError("c must be positive scalar"))
    fc > 0 || throw(ArgumentError("fc must be positive scalar"))

    all(map( x-> x >= -180 && x <=180,az)) || throw(ArgumentError("Az value to be in range [-180,180]"))
    all(map( x-> x >= -90 && x <=90,el)) || throw(ArgumentError("El value to be in range [-90,90]"))

    elg,azg,fcg = ndgrid(el[:],az[:],[fc])
    lambda = c ./fcg
    rcs = Mahafza(azg[:,:],elg[:,:],r1,r2,H,lambda)

    az = collect(az')
    el = collect(el')
    return squeeze(rcs),az,el
end

function rcstruncone(r1,r2,H,c,fc,az = -180:180,el = -90:90)

    r1 >= 0 || throw(ArgumentError("R1 must be nonnegative scalar"))
    r2 > 0 || throw(ArgumentError("R2 must be positive scalar"))
    H > 0 || throw(ArgumentError("H must be positive scalar"))
    c > 0 || throw(ArgumentError("c must be positive scalar"))
    fc > 0 || throw(ArgumentError("fc must be positive scalar"))
    r2>r1 || throw(ArgumentError("R2 value must be > $(r1)"))

    all(map( x-> x >= -180 && x <=180,az)) || throw(ArgumentError("Az value to be in range [-180,180]"))
    all(map( x-> x >= -90 && x <=90,el)) || throw(ArgumentError("El value to be in range [-90,90]"))

    elg,azg,fcg = ndgrid(el[:],az[:],[fc])
    lambda = c ./ fcg[:,:]
    azg = deg2rad.(azg[:,:])
    elg = deg2rad.(elg[:,:])

    tanalpha = (r2-r1)/H
    z1 = r1/tanalpha
    z2 = z1+H

    # non-normal incidence
    alpha = atan(tanalpha);
    rcs = @. lambda.*tanalpha./(8*pi*sin(elg+pi/2)) .* tan(elg+pi/2+alpha) .^ 2; # [1] eq 13.47
    smallendind = elg .< -alpha
    rcs[smallendind] .*= z1
    bigendind = elg .> -alpha              
    rcs[bigendind] .*= z2

    # normal incidence
    ind0 = abs.(elg .- (-alpha)) .< eps()
    rcs[ind0] = @. 8*pi*(z2^(3/2)-z1^(3/2)).^2 ./ (9*lambda[ind0].*sin(elg[ind0]+pi/2)).*tanalpha .*