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Channel estimation is one of key problems in IEEE 802.16e Orthogonal Frequency Division Multiplexing Access (OFDMA) downlink system. Minimum Mean Square Error (MMSE) channel estimation has been known as a superior performance channel estimation. However, this algorithm has high computational complexity. In this paper, we present low complexity(More)
⎯ This paper describes the performance evaluation of fixed step closed loop power control algorithm in a novel wireless channel that is called High Altitude Platforms (HAPs). This new wireless delivery method is proposed as a complementary system in providing the next generation services in which the technology basically employs CDMA. In HAPs communication,(More)
—The implementation of complex signal processing algorithms are required to achieve robust transmission, whereas mobile wireless application require low power dissipation. This paper describes an algorithm and a corresponding hardware architecture for the implementation of OFDMA 802.16e channel estimation. The advantage of the proposed architecture are low(More)
— High mobility communication systems need suitable channel estimation to cope high frequency selectivity and time variation channel. In recent study on Dowwnlink OFDMA Mobile WiMAX, channel estimation was done by exploiting pilot from preamble[3] instead of pilot from data symbol due to ununiformly pilot spacing in this standard. In this paper we propose(More)
In this paper an improved prediction-based power control is proposed for code division multiple access (CDMA) systems in Rayleigh fading channel environments. One of the most serious problems which degrades the performance of power control algorithm is the effect of feedback delay. To overcome the effect of feedback delay, power control needs to employ(More)
In the future, wireless broadband communication systems will not only be used for private access, but also public access with high data rate. The problems in transmitting high data rate at high speed mobility are how to provide wide bandwidth in rapidly changing channel condition, to mitigate selective fading problems, to estimate response of the channel,(More)