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A modified constant modulus algorithm (MCMA) algorithm for adaptive channel equalization for QAM signals is proposed. The proposed algorithm minimizes a cost function that consists of amplitude-and phase-dependent terms. The phase term complements the amplitude-dependent term that is provided by the conventional constant modulus algorithm (CMA). This term should satisfy several properties that guarantee extremum values at the QAM signal levels and at maximum deviations from these levels. Further, the properties should allow symmetry and uniformity across all alphabets. It is shown that the even power co-sinusoidal functions are appropriate for phase term representations. The MCMA is compared with the CMA and the Stop-and-Go Algorithm (SGA) for blind equalization. The performance is evaluated for indoor wireless channels using both transient and steady-state behaviors of the mean square error (MSE). A channel model is developed based on spectral observations of the unlicensed U-NII frequency band, and shown to be time-varying and to exhibit frequency selective fading. While the CMA is successful in achieving good performance, it is shown that both MCMA and SGA are superior and more robust in low SNR environments. The paper also presents a performance comparison of symbol-spaced and sample-spaced equalizations for a single and two-antenna receiver. Simulation results demonstrate that using multi-antenna receiver can effectively improve adaptive channel equalizations by increasing convergence rate and decreasing steady-state mean square error.

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this paper presents a wireless video * Low-end mobile phones, e.g. Nokia 3595 streaming system over Ultra Wide Band (UWB) radio.Wireless video steaming is not a possibility so far due to its **High-endmobilephones e.g.Nokia7710 high bandwidth requirements and high power consumption. Table 1 gives bandwidth analysis of the most With Ultra Wide Band (UWB), a low power, high speed commonly used display devices (internal and external) in radio technology standard developed by the WiMedia the current market. From Table 1, it is easy to find out that Alliance; the dream ofwireless video streaming become true.the bandwidth requirements for many of the display devices By giving the fact of UWB, 480 Mbps with transmission running an average speed of 30 frames/second video mask of -41 dbm/MHz; the UWB supports uncompressed or applications with uncompressed data format have already lossless compressed video screen size up to SVGA exceeded the capacities of those existing wireless (800x600x24) with 30 frames/second rate. This is an technologies. UWB becomes an ultimate solution for the extraordinary achievement concerning wireless video wireless video streaming based on its high bandwidth application. This paper will introduce a demonstration capabilities. system that uses a Nokia 7710 phone as a UWB transmitter

A performance comparison of the Constant Modulus Algorithm ( C M ) and the Stop-and Go Algorithm (SGA) for blind adaptive equalization is presented. The performance evaluation is provided under indoor wireless channels using both transient and steady-state behaviors of the Mean Square Error (MSE). A channel model is developed based on spectral observations of the unlicensed U-NII frequency band. The channel is timevarying and exhibits frequency selective fading. A receiver is implemented as two feed-forward equalizers with one decision feedback equalizer. While the CMA is successful in achieving good performance, the SGA is much superior and more robust in low signal-to-noise ratio environments.t This work is supported by Samoff Corporation, grant No. 450002181 1. 0-7803-6703-0/0 I/$ IO. 00 02001 IEEE