One of main disadvantage of OFDM is high peak-to-average power ratio (PAPR). In this paper, two effective PAPR reduction schemes are proposed. These techniques combine DCT and SLM techniques. The scheme 1 is composed ...One of main disadvantage of OFDM is high peak-to-average power ratio (PAPR). In this paper, two effective PAPR reduction schemes are proposed. These techniques combine DCT and SLM techniques. The scheme 1 is composed of the DCT followed by SLM technique, and the DCT is used followed by conventional SLM in proposed scheme 2. Simulation results show that the proposed schemes can obtain significant PAPR reduction performance with that of ordinary SLM techniques.展开更多
In the H.263 video codec related systems, motion estimation and Discrete Cosine Transform (DCT) have the most computational requirements. In order to reduce complexity of the encoder to dedicate more resources to othe...In the H.263 video codec related systems, motion estimation and Discrete Cosine Transform (DCT) have the most computational requirements. In order to reduce complexity of the encoder to dedicate more resources to other functions, according to the study of existing methods, an Improved All Zero Block Finding (IAZBF) method based on the statistic characteristics of DCT coefficients is proposed. Compared with existing methods, IAZBF improves the detecting efficiency by about 50% without importing too much extra computation requirement. Being computed with additions and shifts instead of complicated multiplications, IAZBF is of low computation complexity, especially for low-end processors. In addition, IAZBF upholds picture fidelity and remains compatible with the H.263 bitstream standard.展开更多
文摘One of main disadvantage of OFDM is high peak-to-average power ratio (PAPR). In this paper, two effective PAPR reduction schemes are proposed. These techniques combine DCT and SLM techniques. The scheme 1 is composed of the DCT followed by SLM technique, and the DCT is used followed by conventional SLM in proposed scheme 2. Simulation results show that the proposed schemes can obtain significant PAPR reduction performance with that of ordinary SLM techniques.
基金Supported by the China Aviation Fund (No. 02153071)
文摘In the H.263 video codec related systems, motion estimation and Discrete Cosine Transform (DCT) have the most computational requirements. In order to reduce complexity of the encoder to dedicate more resources to other functions, according to the study of existing methods, an Improved All Zero Block Finding (IAZBF) method based on the statistic characteristics of DCT coefficients is proposed. Compared with existing methods, IAZBF improves the detecting efficiency by about 50% without importing too much extra computation requirement. Being computed with additions and shifts instead of complicated multiplications, IAZBF is of low computation complexity, especially for low-end processors. In addition, IAZBF upholds picture fidelity and remains compatible with the H.263 bitstream standard.
