摘要(英) |
Orthogonal frequency-division multiplexing (OFDM) systems use the pilot signals to estimate the channel, and restore the received signals to the original signals. But the pilot signals will occupy the bandwidth, limit the transmitting data rate, and make the bandwidth low efficiency.
We apply the method of linear programming to solving this signal estimation problem in a fading channel, and then convert the problem into one that finds the sequence x that minimizes least-square (LS) channel estimation function and then get the regression formula. We apply the branch-and-bound (B&B) algorithm to finding the optimum solution. The advantage is that the pilot signals can be illiminated for estimating the channel and the transmitted information can be recovered..
In this thesis, by using the linked-list method, the B&B algorithm is implemented. It can discard the branches of the useless decoding tree earlier, and that is not necessary to expand all the branches to find the optimal solution, and the solution should be the best solution. |
參考文獻 |
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