Because of the high Peak to Average Power Ratio(PAPR) in Orthogonal Frequency Division Multiplexing(OFDM) system, a union algorithm for PAPR reduction, combined with modified Active Constellation Extension Smart Gradient-Project(ACE-SGP) algorithm and adaptive clipping algorithm, is proposed in this paper. First of all, an adaptive strategy is used to control the size of clipping level A. Secondly, a novel step factor m is adopted to complete iterative computations in order to increase the convergence speed greatly. Simulation results show that the modified algorithm has reduced the PAPR and improved the convergence speed significantly without side information and any processing at the receiver end.
This paper is concerned with the problem of robust H∞ control of nonlinear stochastic systems with timevarying...
Jun Yang,Qiuye Sun and Dongsheng Yang are with the College of Information Science and Engineering,Northeastern University,Shenyang,Liaoning,110819,China.Yizhong Wang is with Shandong University of Science and Technology,Taian,Shandong,271019,China.
Multiple stability for two-dimensional delayed recurrent neural networks with piecewise linear activation flmctions of 2r (r 〉 1) corner points is studied. Sufficient conditions are established for checking the existence of (2r + 1)2 equilibria in delayed recurrent neural networks. Under these conditions, (r + 1)2 equilibria are locally exponentially stable, and (2r+ 1)2 -(r + 1)2 -r2 equilibria are unstable. Attractive basins of stable equilibria are estimated, which are larger than invariant sets derived by decomposing state space. One example is provided to illustrate the effectiveness of our results.