Channel estimation for orthogonal frequency division multiplexing （OFDM） system has attracteo widespread attention. In this paper, a novel efficient two-dimensional （2-D） channel estimation algorithm based on fast...Channel estimation for orthogonal frequency division multiplexing （OFDM） system has attracteo widespread attention. In this paper, a novel efficient two-dimensional （2-D） channel estimation algorithm based on fast Fourier transform （FFT） is proposed for a time-variant, frequency-selective wideband wireless channel. Both theoretical analysis and simulation results are addressed in the paper. The simulation results prove that the proposed algorithm has simpler implementation, better performance and wider application than other traditional deeision-direeted algorithms.展开更多
Along with the more and more attention from people to the environmental problems, people constantly attach higher and higher importance to the environmental accounting. In this paper, the disadvantages of environmenta...Along with the more and more attention from people to the environmental problems, people constantly attach higher and higher importance to the environmental accounting. In this paper, the disadvantages of environmental accounting system are analyzed, and also corresponding measures for transforming the disadvantages are proposed.展开更多
基金the High Technology Research and Development Programme of China(No.2002AA123041)the National Natural Science Foundation of China(No.90104013)Beijing Municipal Science &.Technology Commission(No.KM200610005018)
文摘Channel estimation for orthogonal frequency division multiplexing （OFDM） system has attracteo widespread attention. In this paper, a novel efficient two-dimensional （2-D） channel estimation algorithm based on fast Fourier transform （FFT） is proposed for a time-variant, frequency-selective wideband wireless channel. Both theoretical analysis and simulation results are addressed in the paper. The simulation results prove that the proposed algorithm has simpler implementation, better performance and wider application than other traditional deeision-direeted algorithms.
文摘Along with the more and more attention from people to the environmental problems, people constantly attach higher and higher importance to the environmental accounting. In this paper, the disadvantages of environmental accounting system are analyzed, and also corresponding measures for transforming the disadvantages are proposed.
