Adaptive filtering for selective subband transmission based on interference detection

ABSTRACT

In a shared radio spectrum environment, multiple systems may interfere with each other. In this paper we propose an adaptive filtering method to suppress interference and select the most suitable subbands according to predetermined interference thresholds. Two methods to determine these interference thresholds in Gaussian and multipath fading channels are introduced. The adaptive filtering method enables a system to dynamically use frequency subbands without employing frequency hopping techniques. The flexible received signal bandwidth with different number of subbands provides great potential for systems to coexist with each other, resulting in higher spectrum utilization efficiency. To verify the ectiveness of the proposed adaptive filtering method, the system bit error rates (BERs) under different interference conditions are simulated and compared.

REFERENCES

• 1: Yongjing Zhang , Haitao Wu , Qian Zhang , Ping Zhang, Interference mitigation for coexistence of heterogeneous ultra-wideband systems, EURASIP Journal on Wireless Communications and Networking, v.2006 n.2, p.66-66, April 2006 [doi>10.1155/WCN/2006/40380]
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INDEX TERMS

Primary Classification:
  H. Information Systems
  H.1 MODELS AND PRINCIPLES
      H.1.1 Systems and Information Theory
          Subjects: General systems theory

Additional Classification:
  G. Mathematics of Computing
  G.3 PROBABILITY AND STATISTICS
      Subjects: Statistical computing

General Terms:
Algorithms, Performance

Keywords:
adaptive filtering, interference threshold, subband transmission