JOURNAL OF COMMUNICATIONS (JCM)
ISSN : 1796-2021
Volume : 1    Issue : 1    Date : April 2006

A Harmful Interference Model for Unlicensed Device Operation in Licensed service Bands
Timothy X Brown
Page(s): 13-25
Full Text:
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Abstract
Recent FCC proceedings have considered the notion of unlicensed device operation in licensed
bands. Licensed users are concerned about harmful interference while unlicensed device
manufacturers are concerned that harmful interference is an imprecise design concept. This paper
addresses two elements to these concerns. First, it develops an explicit model of harmful
interference to be included in unlicensed device rules. Such a model provides explicit bounded
protection to the licensed user while providing assurances and performance goals to the
unlicenseddevice manufacturers. Second, it presents an analytic model for assessing harmful
interference that not only provides quantitative analysis, but, also provides insight into how factors
such as directional antennas, power control, and licensed channel avoidance strategies affect the
aggregate interference. Further, it suggests that complex factors such as unlicensed device
modulation schemes can be captured in a simple measurement. These ideas are applied to the
notice of proposed rulemaking on Unlicensed Operation in the TV Broadcast Bands.

Index Terms
harmful interference, unlicensed devices, broadcast service, digital television