A Demonstration of Adaptive Spectrum Sensing and Interference Suppressed Opportunistic Secondary Transmission
نویسندگان
چکیده
We consider spectrum sensing and Non-Contiguous OFDM (NC-OFDM) with interference avoidance to facilitate opportunistic secondary transmission. In this application protecting an incumbent primary user of the spectrum from secondary emissions is a key design requirement. We present an adaptive sense-and-carefully-transmit system which integrates a spectrum sensing module with an NC-OFDM transmitter having a powerful interference avoidance capability. The spectrum sensing module uses a rank-order filtering (ROF) algorithm to automatically set the detection threshold. The interference suppression capability of the NC-OFDM transmitter is enhanced using a technique called Interference Avoidance using Partitioned Frequency and Time domain processing (IA-PFT). We have implemented our Dynamic Spectrum Access (DSA) protocol using the GNU RadioUSRP2 platform. We demonstrate the DSA system performance by experiments performed in the ORBIT Testbed, WINLAB, Rutgers University.
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