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61.
This column presents information of interest to Division 26 members. Included are a candidate's statement from Division member Ludy T. Benjamin, Jr., who is running for President of the American Psychological Association. Also included are a report on the February 1998 Meeting of the APA Council of Representatives; information about the Wallace Russell Fund, nominations for division offices, fellows nominations, and division membership; meeting announcements; and information about access restrictions to the Stanley Milgram papers. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
62.
Orthogonal frequency division multiplexing (OFDM) technique, when used in wireless environments, is known to be robust against
frequency selective fading. However, when the channel shows time selective fading, rapid variations destroy the subcarrier
orthogonality and introduce inter-carrier interference (ICI). The use of ICI mitigation schemes requires the availability
of channel state information (CSI) at the receiver, which is a non-trivial task in fast fading systems. In our work, we have
addressed the problem of estimation of rapidly varying channels for OFDM systems. The channel is modeled using complex exponentials
as basis functions and the estimation process makes use of the cyclic prefix (CP) part available in OFDM symbols as training.
The system is viewed as a state space model and Kalman filter is employed to estimate the channel. Following this, a time
domain ICI mitigation filter that maximizes the received SINR (signal to interference plus noise ratio) is employed for equalization.
This method performs considerably well in terms of MSE as well as BER at very high Doppler spreads.
相似文献
Prerana GuptaEmail: |
63.
64.
The potentiodynamic behaviour of carbon steel in 1.0 M, 2.5 M and 5.0 M NaOH at 20 ± 2°C is reported. The peak potentials and currents were found to vary linearly with the square root of the potential sweep-rate. It is shown that the “pore resistance” model cannot account quantitatively for the cyclic voltammetric behaviour of iron in sodium hydroxide solution. However, the sweep-rate dependencies of ip and Ep suggest that the growth of the film on the surface occurs via an essentially resistive mechanism, which possibly involves the low field migration of ions through an oxide/hydroxide lattice. 相似文献
65.
Yang Xin You Xiaohu 《电子科学学刊(英文版)》2006,23(1):29-34
In this paper, the closed loop transmit diversity technology for the Wideband Code Division Multiple Access(WCDMA) systems is investigated in a multipath Rayleigh fading channel. The RAKE receiver model and the weighing vector algorithm are presented. The performance is theoretically analyzed in terms of the average maximal Signal-to-Noise Ratio(SNR) gain available over the Space-Time block coding based Transmit Diversity(STTD) technology. Theoretic analysis and simulation results show that the closed loop transmit diversity can provide a 3dB performance gain over the open loop scheme in a single path fading channel, while the performance gain decreases dramatically with the increasing inherent multipath diversity of the wireless channel. 相似文献
66.
Yu Guanding Zhang Zhaoyang Qiu Peiliang 《电子科学学刊(英文版)》2006,23(4):485-489
This paper presents an efficient Radio Resource Management (RRM) strategy for adaptive Orthogonal Frequency Division Multiplexing (OFDM) cellular systems. In the proposed strategy, only those users who have the same distance from their base stations can reuse a same subcarrier. This can guarantee the received Carrier-to-Interference ratio (C/I) of each subcarrier to be acceptable as required by system planning. Then by employing different modulation scheme on each subcarrier according to its received C/I, system spectral efficiency can be gracefully increased. Analytical and simulation results show that the spectral efficiency is improved by 40% without sacrificing the Bit Error Rate (BER) performance and call blocking probability and system capacity of the proposed strategy is better than conventional systems. 相似文献
67.
Peng Mugen Wang Wenbo 《电子科学学刊(英文版)》2006,23(4):495-500
In this paper, a theoretical analysis of Time Division Duplex-Code Division Multiple Access (TDD-CDMA) uplink capacity constraint is presented when employing the smart antenna techniques. The evaluation formulations of capacity and load for multi-services are proposed. In order to maximize the throughput, the objective of optimization is proposed, and an advanced uplink resource management algorithm is developed. The proposed algorithm based on the least interference admission control scheme focuses on the maximum throughput for the circuit switched multi-services. The simulation results show that the proposed strategy has a significant improvement in throughput when the optimum admission control threshold is set. 相似文献
68.
Yu Xiangbin Zhang Xiaodong Xu Dazhuan Bi Guangguo 《电子科学学刊(英文版)》2006,23(6):837-841
In this paper, a Complex Wavelet Packet (CWP-MC-CDMA) system uplink model is proposed, based Multi-Carrier Code Division Multiple Access based on the analysis of the principle of MC-CDMA and the use of the optimized complex wavelet packet. Considering that the base station can adopt multiple re- ceiver antennas in the uplink, we employ the Space Diversity Combining (SDC) technique to improve the sys- tem pertbrmance via multiple antennas. The uplink performance of proposed CWP-MC-CDMA system with SDC technique is investigated over Rayleigh lading channel, and corresponding bit error rate analysis is given in detail. The system can avoid the decrease of spectrum efficiency of conventional MC-CDMA due to inserting cyclic prefix. Theoretical analysis and simulation result show that the application of SDC technique can improve the CWP-MC-CDMA system ability to combat spatial lading and various interferences effectively. Moreover, the proposed system based on SDC technique has superior Bit Error Rate (BER) performance over the Discrete Fourier Transform (DFT) and SDC based MC-CDMA system and the real wavelet packet and SDC based MC-CDMA system. 相似文献
69.
70.
This section of News & Notes provides information on current news from Division 26. Included in this section are Minutes of the 2005 Business Meeting of the Society for the History of Psychology (APA Division 26), New Business, History of Psychology Around the World: The British Psychological Society’s History of Psychology Centre, Psychology on Film: The Prelinger Archives of Ephemeral Films and The Archives of the History of American Psychology. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献