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This paper reports on an integrated system of wirelessly linked radiation detectors that are sensitive to alpha, beta,
gamma, and neutron radiation. The detectors use glass and quartz doped with 10B nanoparticles to detect impinging
radiation producing varying optical pulses which exit the material. The varying optical pulses are differentiated by onchip
pulse height spectroscopy. Signal discrimination is done with on-chip CMOS circuitry using a 0.35 μm process
and a photodiode or photo-multiplier (PM) tube. On-chip CMOS interfacing is key to the production of small integrated
radiation detection packages that are cheaper, more reliable, and easier to produce than assembled devices that use
commercial off-the-shelf parts. CMOS packages are designed for low power consumption with maximum battery life;
this lends itself to creating small, hard to detect radiation sensor packages that are easy to integrate with wireless sensor
nodes. The network would use a mesh configuration and transmit real time radiation information from each node to a
local hub. As a radiation source enters the coverage area, the data from sensors in the immediate area is transmitted and
compared to find the location of the source. Pinpointing the source is achieved by comparing data received from each
node. Radiation testing was done using 241Am, 90Sr, and 60Co sources for alpha, beta, and gamma particles. Initial results show that quartz and glass scintillators doped with boron are able to detect each form of radiation. The quartz scintillator is also able to detect neutron radiation particles, which being neutral, are undetected with traditional solid
state radiation detectors.
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