A Location Based Duplex Scheme for Cross Time Slot Interference Reduction in (IEEE 802.22) Cognitive Radio Based Wireless Regional Area Networks (WRAN)

Abstract

Method of utilizing the scarce spectrum in an efficient manner is an (IEEE 802.22) is a standard for Wireless Regional Area Network (WRAN) based on cognitive radio that operates over underutilized portions of TV bands (54 to 862 MHz). Time Division Duplex (TDD) based WRAN cell has advantages such as dynamic traffic allocation, traffic asymmetry to users and ease of spectrum allocation. However, it suffers from severe cross time slot (CTS) interference when the frames of the cells are not synchronized with adjacent (WRAN) cells. In this paper, we propose a Hybrid Division Duplex (HDD) to mitigate the (CTS) interference. The proposed (HDD) system is much more flexible and efficient in providing asymmetric data service and eliminating (CTS) interference by exploiting the advantages of both (TDD) and frequency division duplex (FDD) schemes. Simulation results show that the proposed HDD scheme system can achieve 9 dB improvements in signal to interference ratio compared to conventional (TDD) based (WRAN).