Integrated design of antenna and PCB layers for back-radiation free RFID-enabled mobile devices

A new bi-dimensional antenna array, based on the Yagi-Uda concept, consisting of two driven elements and two passive elements is designed, for UHF-RFID applications, to fit into the case of a portable device (PDA). The multi-layer printed circuit board (PCB), including metal planes, is arranged in a meander-type configuration to cooperate with the array operation in minimizing back radiation with minimal space reduction for components placement. We demonstrate that this approach provides highly efficient radiation performance in the broadside direction with low power loss in the opposite, unwanted direction. This design choice can provide great advantage for long distance RFID-enabled communications.