Myopic sensing for opportunistic spectrum access using channel correlation

ABSTRACT

We consider secondary user performing opportunistic spectrum access (OSA) over multiple correlated channels occupied by primary users. The channel occupancy states can be modeled as a discrete-time Markov process. Due to hardware and energy limitations, secondary user can choose only one channel to sense in each slot. Based on the sensing outcome, it decides its access action. Hence, channel selection scheme (i.e. sensing policy) at the MAC layer is of vital importance for secondary user's throughput and sensing policy design can be formulated as a partially observable Markov decision process (POMDP). Unlike other research, in which case the channel occupancy states (induced by primary users) evolving independently among multiple channels, our work emphasizes on the case that multiple channels are not independent any more, then they evolve dependently. By adopting myopic sensing, which is an approach with low complexity to implement POMDP, we propose a myopic sensing policy exploiting the channel correlation in this paper. Numerical results illustrate that the proposed sensing policy improves the throughput of the secondary user either with or without the presence of spectrum sensing error.

REFERENCES

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INDEX TERMS

Primary Classification:
  D. Software
  D.2 SOFTWARE ENGINEERING
      D.2.1 Requirements/Specifications

General Terms:
Algorithms, Performance

Keywords:
POMDP, channel correlation, myopic sensing, opportunistic spectrum access