Printed circuit board including electromagnetic bandgap structure

Abstract

Embodiments of the present invention provide a printed circuit board, which includes an electromagnetic bandgap structure disposed around an antenna, so as to prevent noise from being transmitted to the antenna. The printed circuit board includes an antenna, a circuit chip, a plurality of metal layers and a plurality of dielectric layers, a pair of transmission lines for transmitting a signal to the antenna, and an electromagnetic bandgap structure disposed between the antenna and the circuit chip and for preventing an electromagnetic wave from being transmitted from the circuit chip to the antenna.

What is claimed is: 
     
         1 . A printed circuit board, comprising:
 an antenna;   a circuit chip;   a plurality of metal layers and a plurality of dielectric layers;   a pair of transmission lines configured to transmit a signal to the antenna; and   an electromagnetic bandgap structure disposed between the antenna and the circuit chip in the printed circuit board and configured to prevent an electromagnetic wave from being transmitted from the circuit chip to the antenna,   wherein the electromagnetic bandgap structure comprises a dielectric layer; a plurality of conductive plates; and a stitching via configured to electrically connect the conductive plates to each other, and   wherein the stitching via passes through the dielectric layer, and a part of the stitching via is placed in a planar surface that is different from a planar surface in which the conductive plates are placed.   
     
     
         2 . The printed circuit board as set forth in  claim 1 , wherein the stitching via comprises:
 a first via passing through the dielectric layer and having an end part being connected to any one of two adjacent conductive plates, and a second via passing through the dielectric layer and having an end part being connected to the other of two adjacent conductive plates; and   a connection pattern having one end part being connected to the other end part of the first via and the other end part being connected to the other end part of the second via.   
     
     
         2 . The printed circuit board as set forth in  claim 2 , further comprising:
 a conductive layer, wherein the dielectric layer is placed between the conductive plates and the conductive layer.   
     
     
         4 . The printed circuit board as set forth in claim  3 , wherein the conductive layer comprises a-clearance hole, and the connection pattern is accommodated in the clearance hole. 
     
     
         5 . The printed circuit board as set forth in  claim 1 , wherein the conductive plates have a polygonal, circular or elliptical shape. 
     
     
         6 . The printed circuit board as set forth in  claim 1 , wherein the conductive plates have the same size 
     
     
         7 . The printed circuit board as set forth in  claim 1 , wherein the conductive plates are distinguished into a plurality of groups having different conductive plate sizes. 
     
     
         8 . The printed circuit board as set forth in  claim 1 , wherein the conductive plates are placed on the same planar surface.