Optimization of Sensing Receiver for Cognitive Radio Applications

Abstract

We propose an optimized dedicated broadband sensing receiver architecture for use in cognitive radios supporting delay sensitive applications. Specifically, we first reason the need for a dedicated sensing receiver that employs a combination of coarse and fine scanning to reduce sensing time over a large bandwidth. We derive an expression for mean acquisition/detection time as a function of a number of parameters including the number of coarse and fine frequency bins employed. We then determine the optimal number of coarse and fine bins that minimize the overall detection time required to identify idle channels under various system conditions. Using analytical and simulation results, we quantify the dependence of optimal coarse and fine bin selection on system parameters such as (1) size of FFT used in scanning; (2) probability of detection and false alarm of the underlying sensing algorithm; (3) signal-to-noise ratio of the received signal, and (4) expected number of available channels. The primary contribution of this work lies in a practical realization of an optimal broadband sensing receiver.

Discovering and exploiting spectrum power correlations in cognitive radio networks: an experimentally driven approach

“…In a similar manner, a relevant technique [28] is proposed in the context of LTE protocol -which realizes practically cognitive radio concepts -for enhancing the white space detection procedure, introducing novel sensing techniques for both coarse and fine stages. Finally, works like [29] aim at determining the optimal frequency block size for both coarse and fine sensing stages while requiring prior knowledge on the parameters of the utilized equipment, the used sensing algorithm, and the expected signals to be sensed. However, the imposed requirements are considered quite restrictive, thus rendering their application difficult in practice.…”

Implementation Dedicated Sensing Receiver (DSR) in 3G - WiFi Offload

“…The broader the scanned spectrum, the higher the probability of finding an available channel suitable for CR operation. In [7], CRNs will provide high bandwidth to mobile users via heterogeneous wireless architectures and dynamic spectrum access techniques, some challenges may still be imposed by CRNs due to the dynamic spectrum environment and the diverse QoS requirements of various applications. The heterogeneity of the CRNs, especially that exhibited in a multi-user environment with the coexistence of CR users and primary users, introduces new challenges to the spectrum management and sharing.…”

“…According to the [7] research, the DSR is defined as an algorithm which has the ability to perform sensing based on the presence of Primary Users transmitter, to subsequently make a per-band scheduling for the wide bandwidth to make an estimation of the operational pattern to be followed on the heterogeneous network. More specifically, in [8] a research was conducted in order to improve the performance and efficiency of the mobile station to perform the handover with an optimal quality of service, while still in the area covered by several existing wireless networks with taking into consideration the unused bandwidth of the target networks.…”