Flexible wireless pressure sensor module

A flexible wireless pressure sensor module for implantable blood pressure sensing has been developed using chip embedded flexible packaging (CEFP) technology. The CEFP can provide wireless communication platform, which is composed of thinned silicon chips (RFIC) and antenna. The mechanical characteristics of the thinned silicon chips for flexible communication platform are analyzed using a bending test and computer simulation. The realized sensor is mechanically flexible and can be easily attached to the outside of the blood vessel. The pressure sensor consists of a flexible capacitance type sensor system including LC resonator, which is wrapped onto the blood vessel and can remotely monitor the blood pressure. As blood pressure changes, the blood vessel either expands or shrinks. The sensor system recognizes blood pressure variation due to changing the distance between the electrodes and hence, capacitance. While the applied pressure changes from 0 to 213.3 kPa the resonator frequency changes correspondingly. The sensitivity of the implantable blood pressure is 11.25 kHz/kPa. The proposed flexible wireless sensor module can be used as a basic platform in a ubiquitous sensor network system. (C) 2005 Elsevier B.V. All rights reserved.