【正文】 Medical Device Interface (MDI). This MDI will allow the device to receive and transmit data within the wireless sensor work. This inexpensive hardware will be generic to fit a wide range of medical devices. Similarly the firmware can be kept generic and any specific device munication protocols can be implemented on a server on the work backend. The work described in this paper is part of a larger project, the goal of which is to provide a plete patient monitoring system. Other features of the overall system will be to provide ECG (Electrocardiogram) and PulseOximetry data in a novel way over a wireless sensor work using expertise gained on prior projects [2]. RELATED WORK The concept of using wireless sensor works for Medical Care and wireless patient monitoring has been explored by others but integrating data from other devices is generally not discussed. There is ongoing related work in patient monitoring using wireless sensors such as the “CodeBlue” project at Harvard [3]. Others have also proven successful with wireless sensor works designs for medical sensors [4] and in the management of sensor data [5]. It has been identified that it is desirable to wirelessly enable existing medical devices that provide vital signs data using technologies such as Zigbee [6], [7]. The research described in this paper aspires to meet these requirements. The use of wireless sensor works within the hospital has been extensively examined. Moreover, other wireless technologies within the same frequency band, such as IEEE [8], have existed within the hospital for some time [9]. III. REQUIREMENTS ANALYSIS Wireless Technologies Established standards for wireless applications, such as Bluetooth [10] and IEEE , allow high transmission rates, but at the expense of power consumption, application plexity, and cost. Zigbee offers low cost, low power devices that can municate with each other and the outside world. ZigBee39。s selfforming and selfhealing meshwork architecture lets data and control messages pass from one node to another by multiple paths. This is particularly useful in a hospital environment where interference from walls, people and general obstacles is a major issue. Zigbee is based upon the IEEE standard [11] for radio hardware and software specification. Mobility Zigbee enabled devices support a sleep mode. An offline node can connect to a work in about 30 ms .Waking up a sleeping node takes about 15 ms, as does accessing a channel andtransmitting data. If the requirement is to collect data once a minute the device can be placed in a power saving mode saving significant amounts of energy and increasing the battery life. In sleep mode a Zigbee chip can assume as little as [12]. This is particularly important in a medical setting where patients are often on the move while still attached to medical devices. Coexistence Both Zigbee and operate in the licensefree industrial scientific medical (ISM) frequency is already in widespread use within hospitals which would encourage the adoption of Zigbee solutions in the same environment. However care has to be taken to avoid interference between these 2 neighbouring technologies as described in the paper entitled “Coexistance of with other systems in the ” [13]. By selecting an appropriate channel, after performing a simple site survey, these problems can be easily avoided. Device Parameters Typical readings available on a ventilator are Inspiratory Tidal Volume, Expiratory Tidal Volume, O2 concentration, Respiratory Rate, Peak Pressure, Expired Minute Volume and Mean Airway Pressure. The settings on the ventilator are also of interest to medical staff. The most typical settings we’ve chosen are Inspiratory Tidal Volume, Minute Volume, O2 Concentration, I:E Ratio, Breath Duration and Inspiratory Flow. Similarly we have chosen some mon parameters for Vital Signs Monitors. These are Respiratory Rate, Non Invasive Blood Pressure, SPO2 and Temperature. The third device we selected parameters for is the Unfusion Pump. The mon parameters we are most interested in here are Volume, Time, Ramp and Occlusion Pressure. Further parameters can be easily added to t