Tanim M. Taher

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This paper summarizes some of the results of measurements and related analysis efforts at the Illinois Institute of Technology (IIT) Spectrum Observatory in Chicago over the past three years. The results are unique in the sense that the spectral occupancy estimates are based on multiple years of observations, whereas previous studies produced occupancy(More)
– Radios for public safety communication have some of the most stringent requirements for access, reliability and robustness. While wireless technology has seen tremendous strides in the past decade, large parts of the public safety infrastructure have unfortunately lagged behind. Today a large number of the Land Mobile Radios (LMR) used by police and fire(More)
Some devices not used for data communications radiate in the 2.4 GHz Wireless-Fidelity (Wi-Fi) band, thus causing unintentional interference that degrades the performance of IEEE 802.11 wireless systems. An analytical model for radio emissions from one of the most common unintentional interferers, the residential microwave oven, is developed from laboratory(More)
The microwave oven (MWO) is a commonly available appliance that does not transmit data but still radiates signals in the unlicensed 2.4 GHz Industrial, Scientific and Medical (ISM) band. The MWO thus acts as an unintentional interferer for IEEE 802.11 Wireless Fidelity (Wi-Fi) communication signals. An analytic model of the MWO signal is developed and(More)
This paper describes the current efforts underway to set up matched long-term continuously running spectrum observatories in the US (in Chicago and Blacksburg) and in Turku, Finland. The measurement equipment setup is described, along with the architecture for the networked database used to aggregate, archive and share the spectrum measurement data(More)
An RF measurement system with high time resolution is implemented to determine the statistical characteristics of various channels in the Land Mobile Radio bands. The applicability of simple statistical models to the observed data is investigated, as well as their validity over short and long periods of time. The results show that the statistics of the idle(More)
In 2007, the Wireless Network and Communications (WiNCom) Research Center at the Illinois Institute of Technology initiated a continuous RF spectrum measurement program in the frequency range 30 MHz to 6 GHz. The data measurement collection, now multiple Terabytes, was historically stored in a flat file format on multiple hard drives which was efficient and(More)
We present the results of a preliminary assessment of the potential for applying Dynamic Spectrum Access (DSA) methods to improve radio frequency spectrum utilization in the land mobile radio (LMR) bands in the U.S. This band includes both public safety and commercial user frequency assignments. First, using RF spectrum measurements made in Chicago,(More)
The MicroWave Oven (MWO) is a commonly available appliance that does not transmit data, but still radiates signals in the unlicensed 2.4 GHz Industrial, Scientific and Medical (ISM) band. The MWO thus acts as an unintentional interferer for IEEE 802.11 Wireless Fidelity (Wi-Fi) communication signals. An analytic model of the MWO signal is developed and(More)