Rice Wireless

Permanent URI for this collection

https://hdl.handle.net/1911/21945
Formerly the Center for Multimedia Communications, Rice Wireless is part of the university's Electrical and Computer Engineering Department. More information about the group can be found at http://wireless.rice.edu/.

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Browsing Rice Wireless by Subject "algorithm"

Now showing 1 - 3 of 3
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    On-line Arithmetic for Detection in Digital Communication Receivers
    (2001-06-20) Rajagopal, Sridhar; Cavallaro, Joseph R.; Center for Multimedia Communications (http://cmc.rice.edu/)
    This paper demonstrates the advantages of using on-line arithmetic for traditional and advanced detection algorithms for communication systems. Detection is one of the core computationally-intensive physical layer operations in a communication receiver and determines the communication data rates. Detection algorithms typically involve hard decisions} (sign based testing) to find the sign of the transmitted information bit. This results in extraneous computations in a conventional number system as the sign is obtained only at the end due to the Least Significant Digit First (LSDF) nature of computations. On-line arithmetic, based on a signed digit number representation, provides Most Significant Digit First (MSDF) computation. Hence, the computations can stop after the first non-zero MSD (sign) is computed and additional computations for the successive digits can be avoided. Back-conversion to a conventional number system is not required as the sign of the digit represents the detected bit. A comparison of a radix-4 serial digit on-line multiuser detector with an 8-bit parallel conventional arithmetic multiuser detector shows a decrease in latency by 1.95X, a 3X increase in throughput, and possible savings in area.
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    Reduced Rank Algorithms for Wireless Space-Time Channels
    (2000-05-20) Ndili, Obianuju; Center for Multimedia Communications (http://cmc.rice.edu/)
    The estimation of channel coefficients constitutes a major function of the receiver. It is also an important step in the signal detection process at the receiver, in a wireless communication system. To describe the space-time channel from multiple transmitters to a single receiver, many parameters are required. This means that in order to perform channel estimation and signal detection, the order P say, of the required filter will be very large. Since the channel is time varying thus the filter adaptive, a large P implies a slow response to changing channel conditions. This is one motivation for reduced-rank adaptive filtering. In this project, several aspects of space-time channel parameter estimation, and signal detection, are examined. Three methods have been studied. A maximum likelihood channel estimation method and two different subspace-based, reduced-rank methods - the "cross-spectral" method and the "residual correlations" method.
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    W-CDMA real-time algorithm implementation and evaluation
    (2000-05-20) Jones, Bryan Allen; Center for Multimedia Communications (http://cmc.rice.edu/)
    This paper describes a platform to enable and explore the design and implementation of next-generation CDMA wireless base stations. A DSP and FPGA-based multiprocessor board is integrated into a Simulink-based wireless testbed environment, providing the ability to simulate the behavior and performance of new algorithms. Performance measurements are taken and analyzed, demonstrating key areas for algorithm improvement.