  This paper addresses the design and implementation of a real-time monitoring
system consisting of wireless thermometers for continuous recording of neonate
body temperature in an intensive care unit (ICU). Each wireless thermometer
incorporates an accurate semiconductor temperature sensor, a transceiver
operating on ISM frequency band (i.e., 915 MHz) as well as a microcontroller
which is used to control the thermometers functionalities including wireless
medium access (e.g., free space or body channel), transmission and reception. A
voltage regulator and a low-pass filter were also used for removing spurious
signals and environmental noise from the thermometer feed line. In order to
distinguish the reading of each thermometer from measurements performed by
other thermometers, the I-wire protocol was used. This protocol can securely
tag the temperature value by incorporating a unique ID (provided by the
manufacturer) into the packet sent wirelessly. An array of two thermometers was
implemented and successfully tested in different scenarios, namely free-space,
water (immersed thermometers) and on a volunteers wrist. Moreover, an in-house
developed computer software was used in order to visualize the readings in
addition to alerting rapid increase and high body temperature. The software
also compares the measurement results with actual values. The agreement between
the experimental data and real temperature values is reasonably acceptable and
that of the on-body testing is significant. Keywords : Temperature measurement,
Wireless thermometer, Temperature sensors, Wireless sensor networks, Wireless
communication, Monitoring, Protocols, Time measurement
