Time filter

Source Type

Dai X.,Sun Yat Sen University | Li Y.,Sun Yat Sen University | Li Y.,CMU Shunde International Joint Research Institute | Yu B.,Sun Yat Sen University | Su D.,Sun Yat Sen University
Shuju Caiji Yu Chuli/Journal of Data Acquisition and Processing | Year: 2015

Traditional compression algorithms of OFDM signals with low compression ratio and signal to quantization-error ratio (SQR) come along with a high error rate, which fail to meet the requirements of OFDM systems. To achieve the high compression ratio and the low error rate, a new algorithm is proposed based on a combination of clipping with tail plug (CTP), geometric series companding (GSC) and partial sample calibration (PSC). The new algorithm can achieve the nearly loss-less compression and the compression ratio can be as high as 1.86:1 with a error rate less than 10-7, while SQR corresponding to the quantization error is 70 dB in 4096-QAM OFDM signal modulation schemes meeting the requirements of the FTTdp+GDSL systems well. ©, 2015, Journal of Data Acquisition and Processing. All right reserved.

Xue Z.,Sun Yat Sen University | Xue Z.,CMU Shunde International Joint Research Institute | Wu D.,Sun Yat Sen University | Wu D.,CMU Shunde International Joint Research Institute | And 4 more authors.
IEEE Transactions on Circuits and Systems for Video Technology | Year: 2015

Cloud gaming has emerged as a promising approach to more affordable and accessible games. By rendering high-end video games in the cloud and streaming encoded game scenes to players via the broadband networks, users are relieved from downloading or installing game software. With cloud gaming, users can easily play high-end 3-D video games on any devices anytime and anywhere. In this paper, we conducted a comprehensive measurement study of a leading cloud gaming system in China, namely, CloudUnion. Unlike the previous work, our measurement study was based on an in-depth understanding of the internal mechanisms of CloudUnion, and thus we were able to reveal problems that cannot be observed in a black-box approach. We built a dedicated measurement platform, which enables us to study CloudUnion from different views, including the global view, local view, and user view. We also conducted a comparison study with another cloud gaming system, namely, GamingAnywhere. Our measurement results unveil the pros and cons of the current cloud gaming system design, and bring forth important insights about the cloud infrastructure, user behaviors, traffic patterns, user-perceived quality, and so on. Our work will be valuable for the design of future cloud gaming systems. © 2015 IEEE.

Zheng S.Y.,Sun Yat Sen University | Zheng S.Y.,CMU Shunde International Joint Research Institute | Wu Y.,Beijing University of Posts and Telecommunications | Li Y.,Sun Yat Sen University | And 4 more authors.
IEEE Transactions on Components, Packaging and Manufacturing Technology | Year: 2014

For the first time, a patch hybrid coupler that can provide arbitrary power division ratios over two arbitrary frequency bands, is presented in this paper. Complementary split ring resonators (CSRRs) are loaded onto each quadrant of a patch hybrid coupler to enable dual-band operation. The unique property of CSRR was found to give different power division ratios over the two frequency bands, which is difficult to implement using conventional approaches. An equivalent circuit has been extracted and used to describe the operating principles, along with the presentation of parametric analysis. To demonstrate the flexibility in realizing arbitrary power division ratios in two different frequency bands, five dual-band patch hybrid couplers are designed, fabricated, and measured. Good agreement between the simulated and measured results consolidates the work proposed. © 2014 IEEE.

Discover hidden collaborations