Low power programmable prototype sensor for remotely pressure monitoring

In this paper, a miniaturized, low power, bidirectional wireless communication system has been developed to be used for in vivo pressure monitoring. The system prototype consists of miniature FSK transceiver integrated with Microcontroller unit (MCU) in one small package, chip antenna, and capacitive interface circuitry based on Delta-sigma (SigmaDelta) modulator. At the base station side, the same transceiver chip is communicating with a PC through a graphical user interface (GUI) to either sends/receives commands/data. Industrial, Scientific and Medical (ISM) band RF (433 MHz) was used to achieve half duplex communication between the two sides. A digital filtering has been used in the capacitive interface to reduce noise effects forming capacitance to digital converter (CDC). All the modules of the mixed signal system are integrated in a printed circuit board (PCB) of size 22.46 x 20.168 mm.