This paper proposes a simple method to enlarge the estimation range of conventional carrier frequency offset (CFO) estimation methods based on correlations among the identical parts of the preamble. A novel preamble i...This paper proposes a simple method to enlarge the estimation range of conventional carrier frequency offset (CFO) estimation methods based on correlations among the identical parts of the preamble. A novel preamble is designed, which is composed of one regular OFDM training block with even numbers of identical parts and one irregular OFDM training block with odd numbers of identical parts. The initial estimates obtained over the two training blocks are next exploited to jointly estimate the CFO. By elaborately selecting the numbers of identical parts for the two training blocks, the proposed CFO estimator can estimate frequency offset over tens of the subcarrier spacing. Simulation results showed that the proposed CFO estimator satisfies the estimate range requirement for the practical OFDM systems, while achieving a very good estimate performance.展开更多
In this paper,we introduce the combining stated preference and revealed preference methods which is the state-ofthe-art method for the valuation of non-market goods.Revealed preference methods and stated preference (S...In this paper,we introduce the combining stated preference and revealed preference methods which is the state-ofthe-art method for the valuation of non-market goods.Revealed preference methods and stated preference (SP) methods have both been applied by economists in valuing non-market goods;however both methods have inherent weaknesses.In order to exploit the strengths of the various approaches while minimizing their weaknesses,combining the two methods has become an important methodological option.Up to now,a growing number of literatures of studying combing the two types of data have evolved,and researchers developed three types of models to estimate combining revealed preference and stated preference data in academic fields:discrete choice model,continuous choice model and mixed choice model.Combining stated and revealed preference methods have been developed fast especially in the transport study field in which ideas could also be leant for environmental economic studies.展开更多
基金Project supported by the Hi-Tech Research and Development Pro-gram (863) of China (No. 2003AA12331007) and the National NaturalScience Foundation of China (No. 60572157)
文摘This paper proposes a simple method to enlarge the estimation range of conventional carrier frequency offset (CFO) estimation methods based on correlations among the identical parts of the preamble. A novel preamble is designed, which is composed of one regular OFDM training block with even numbers of identical parts and one irregular OFDM training block with odd numbers of identical parts. The initial estimates obtained over the two training blocks are next exploited to jointly estimate the CFO. By elaborately selecting the numbers of identical parts for the two training blocks, the proposed CFO estimator can estimate frequency offset over tens of the subcarrier spacing. Simulation results showed that the proposed CFO estimator satisfies the estimate range requirement for the practical OFDM systems, while achieving a very good estimate performance.
文摘In this paper,we introduce the combining stated preference and revealed preference methods which is the state-ofthe-art method for the valuation of non-market goods.Revealed preference methods and stated preference (SP) methods have both been applied by economists in valuing non-market goods;however both methods have inherent weaknesses.In order to exploit the strengths of the various approaches while minimizing their weaknesses,combining the two methods has become an important methodological option.Up to now,a growing number of literatures of studying combing the two types of data have evolved,and researchers developed three types of models to estimate combining revealed preference and stated preference data in academic fields:discrete choice model,continuous choice model and mixed choice model.Combining stated and revealed preference methods have been developed fast especially in the transport study field in which ideas could also be leant for environmental economic studies.