The flexible and configurable Sussex EIM MK4 using PCI eXtensions for Instrumentation (PXI)

Abstract

The Sussex Electrical Impedance Mammography (EIM device is a novel imaging system developed at the University of Sussex for the detection of breast lesions in-vivo using quadrature detection of impedance. The device uses a fully programmable planar array of electrodes. The control method employed is such that any two electrodes apply current to the breast whilst any other two, similarly non-invasive, electrodes detect the developed potential difference under the direction of proprietary software. The currents injected are provided by a signal source with available output frequencies that are continuous over a wide bandwidth. The system is a prototype device for research and clinical evaluation, therefore maximum flexibility is required for hardware and software settings. This paper describes how we have achieved a totally configurable system with a quick turn-around in development time using off-the-shelf hardware and a 3U PXI Chassis. The system is based around a National Instruments PXI (PCI eXtensions for Instrumentation) chassis which is a modular electronic instrumentation platform. The modules are register-based products, which use software drivers hosted on a PC to configure them as useful instruments, taking advantage of the increasing power of PCs to improve hardware access and simplify embedded software in the modules.