Communication sheet and communication system

A first sheet-like conductor (10) of this communication sheet (100) has a plurality of openings formed by a plurality of intersecting linear conductors (11). A second sheet-like conductor is a flat plate facing the first sheet-like conductor (10) with a gap therebetween. A wireless substrate (20) has a linear antenna that runs parallel to one linear conductor (11a) among the plurality of intersecting linear conductors (11). 通信片材（100）的第片材状导体（10）具有多个由多个交叉的线状导体（11）形成的开孔。第二片材状导体为与第片材状导体（10）空开间隙相对的平板。无线基板（20）具有与多个交叉的线状导体（11）之中的个线状导体（11a）平行的线状天线。