documentclass[tikz,border=3mm]{standalone}

usetikzlibrary{calc}
usepackage{pgfplots}
pgfplotsset{compat=1.15}
usepgfplotslibrary{polar}

usepackage{filecontents}
begin{filecontents*}{radar.csv}
    angle,radius,class,name
    130,    4,  1,  a
    348,    3,  1,  b
    212,    5,  2,  c
    56,     2,  2,  d
end{filecontents*}

begin{document}
begin{tikzpicture}
    begin{polaraxis}[
        width=8cm, height=8cm,
        visualization depends on={value thisrow{name} as labelname}
        ]
        addplot[
            scatter, only marks,
            point meta=explicit symbolic,
            mark options={
                text mark=labelname,
                text mark as node=true,
                text mark style={circle,inner sep=1pt,draw}
            },
            scatter/classes={
                1={
                    mark = text,
                    mark options={
                        text mark style={square,inner sep=2pt,draw}
                        },
                    blue
                    },
                2={
                    mark = text,
                    mark options={
                        text mark style={*triangle}
                        },
                    red
                    }
                }
            ]
            table[ x=angle, y=radius, meta=class, col sep=comma
            ] {radar.csv};
    end{polaraxis}
end{tikzpicture}
end{document}