Paper Info
Title
Cooperative Wideband Spectrum Detection Based on Maximum Likelihood Ratio for CR Enhanced VANET.
Abstract
Cognitive radio (CR) enhanced vehicular ad hoc network (CR-VANET) is a special VANET that each vehicle could explore local spectrum gap and reduce data congestion by mitigating interference by dynamically accessing spectrum holes. One of the most important challenges for CR-VANET is to identify the presence of primary users (PU) over wideband spectrum at a particular time and specific geographic location. In this paper, maximum likelihood ratio (MLR) detection is proposed as an effective scheme for wideband spectrum detection in orthogonal frequency division multiplexing (OFDM) based overlay CR-VANET. OR fusion rule with square-law selection (SLS) is implemented at roadside to make global detection decision by means of the combination of each vehicle's local sensing results. Hence, cooperative wideband spectrum detection is implemented in dynamic topology CR-VANET to enhance the reliability of spectrum detection. Specifically, robust cooperative sensing technique is investigated with the consideration of sensing channel SNR, reporting channel fading, as well as inter-user error rate, with the purpose of exploiting diversity in multi-vehicle cooperative sensing scenario. Limitations of cooperative wideband spectrum sensing are presented with MLR detection in space-time block code (STBC) and time division multiple access (TDMA) protocols for practical consideration. Simulation results are presented to confirm our theoretical derivations. It is revealed that, compared with conventional energy detection (ED), cooperative wideband spectrum detection with MLR has adaptive detection thresholds. Moreover, robust cooperative sensing by roadside SLS OR rule and its limitations are also performed with receiver operation characteristics (ROC). It is proven that, MLR detection is available in robust cooperative sensing with dynamic threshold variations for CR-VANET practical applications. © 2013 Engineering and Technology Publishing.
Year
DOI
Venue
2013
10.12720/jcm.8.12.814-821
JCM
Keywords
DocType
Volume
square-law selection (sls),inter-user error rate,cr enhanced vanet (cr-vanet),likelihood ratio (mlr),cooperative wideband spectrum detection,receiver operation characteristics (roc)
Journal
8
Issue
ISSN
Citations 
12
null
1
PageRank 
References 
Authors
0.35
14
4
Name
Order
Citations
PageRank
Xiaorong Xu110.35
Jianong Bao210.35
Yi Luo320.71
Huaxia Wang4173.62