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Full-Text Articles in Computer Engineering
Performance Comparison Of The Stbc-Ofdm Decoders In A Fast Fading Channel, Chi-Min Li, Guo-Wei Li, Han-Yi Liu
Performance Comparison Of The Stbc-Ofdm Decoders In A Fast Fading Channel, Chi-Min Li, Guo-Wei Li, Han-Yi Liu
Journal of Marine Science and Technology
In a fast fading channel, the orthogonality of the two consecutive STBC-OFDM symbols will be destroyed and the received signals can not be perfectly separated. As a result, the bit error rate (BER) performance will be degraded seriously. In this paper, we analyze several co-channel interference (CCI) cancellation decoders for the STBC-OFDM in a fast fading channel including the Alamouti method, SIC method, ML method, DMLD method, and a proposed DZFD method. The proposed DZFD method has the advantage of reducing the computational complexity for the DMLD method. We also conduct the outdoor channel measurements to verify the CCI cancellation …
A Partition Dummy Sequence Insertion Papr Reduction Method Of The Ofdm System, Chi-Min Li, Jia-Chyi Wu, Chao-Chin Tseng
A Partition Dummy Sequence Insertion Papr Reduction Method Of The Ofdm System, Chi-Min Li, Jia-Chyi Wu, Chao-Chin Tseng
Journal of Marine Science and Technology
OFDM (Orthogonal Frequency Division Multiplexing) technique has been widely adopted in many wireless communication systems due to its high data-rate transmission ability and robustness to the multipath fading channel. One major drawback of the OFDM signal is the high peak-toaverage power ratio (PAPR) problem. The high PAPR results in the in-band distortion and out-of-band radiation when the OFDM signal is fed into a nonlinear power amplifier (PA). In this paper, we propose a partition dummy sequence insertion (PDSI) method to reduce the PAPR problem. Simulation results of the PAPR reduction and bit error rate (BER) performance for the proposed method …
A Color Image Authentication And Recovery Method Using Block Truncation Code Embedding, Shu-Chien Huang, Ching-Fen Jiang
A Color Image Authentication And Recovery Method Using Block Truncation Code Embedding, Shu-Chien Huang, Ching-Fen Jiang
Journal of Marine Science and Technology
A new method for color image authentication and recovery is proposed in this paper. To achieve this goal, the least significant bit (LSB) and the second LSB of the spatial domain were selected to embed the watermark. The watermark consists of two parts: authentication data and recovery data made by block truncation code and bitmap. According to the experimental results, the image embedded within the authentication data and recovery data can still preserve high image quality. The results also reveal that the tampered images can be successfully recovered with acceptable visual quality.