Cooperative Sequential Sensing of Radio Transmissions in 5G with Improved Cost-Delay Tradeoff

Abstract

The fifth-generation (5G) wireless networks are generally anticipated to be heterogeneous, consisting of macro cells, wireless local area networks, device-to-device networks, ad hoc networks, and so forth. The spectrum occupancy varies on spatial and temporal basis. So sensing the variation of spectrum occupancy and informing the resource scheduler can optimize the utilization efficiency of spectrum. Especially for deployment of cognitive radio in 5G, spectrum sensing is regarded as a key technique. In this work, we study the cooperative sensing in 5G heterogeneous wireless networks with a centralized control module. By formulating this cooperative sensing problem as a sequential binary hypothesis test problem, the number of unnecessary data samples and the associated cost is substantially reduced, with guaranteed detection precision. We develop a cooperative sequential detection algorithm, in which multiple geographically diverse sensors are sequentially set up to measure and transmit measurement results on demand. Furthermore, we consider different sensor sampling schemes to address the cost-delay tradeoff problems and then propose a conditional mean activation and sampling algorithm, in which the number of required samples is predicted based on the quality of the collected samples. The performances of different sensor sampling schemes are demonstrated under different sensing environments.

Non-cooperative and Cooperative Spectrum Sensing in 5G Cognitive Networks

“…Within this context, one of the main challenges is the energy efficiency, to be achieved by minimizing SS efforts and control message exchange. For this reason, when considering centralized CSS, a sequential SS algorithm with hibernation state for the sensing devices has been proposed in [45], while external CSS architecture with dedicated network entities referred to as spectrum agents (SAs) has been recently discussed in [46]. Even in this case, mechanisms for energy efficiency are highlighted: the SAs are in fact supposed to be activated through an explicit sensing request either by the SBS/SUE needed to transmit or by a central unit that is also in charge of the final decision on the resource occupancy.…”

Cooperative composite sequential detection and its application in spectrum sensing

“…They investigated the transmission of the extracted statistics by the SUs to the fusion centre (FC). In [11], the SD is employed for sensing the radio transmissions in the fifth‐generation (5G) in which the channel gain and noise variance are known. An SD is designed in [12] to optimise the sensing time considering some constraint on the PU system where the signal‐to‐noise ratio (SNR) value of PU signal is known.…”