Multichannel handheld hard-tissue bio-impedance meter with bluetooth link

Abstract

A commercial multichannel handheld device for hard tissue bio-impedance measurement is presented. It consists of a battery powered 100% autonomous device including Bluetooth capability. It complies with IEC60601-1 electrical safety and electromagnetic compatibility requirements. It includes an analog multiplexer for channel selection, as well as several buttons, led's and a LCD for menu navigation and user interface. The device is able to measure impedances from 10KΩ to 10MΩ within 200Hz to 20KHz frequency range, with a maximum error of 3% in module and 3° in phase. It can carry out a 20 point frequency sweep within the specified range in less than 1 second. Low power design techniques have been implemented, giving the device 8h of minimum autonomy when continuous measurements are taken. It includes a Bluetooth module for bidirectional data transmission, allowing it to work autonomously or linked to a PC or PDA, which can be used for data monitoring or to fully control the device. Bench test results using dummy cells consisting of parallel connected resistors and capacitors, from 10KΩ to 10MΩ and from 20pF to 100pF, will be discussed. © Springer-Verlag 2007.