Now showing items 1-20 of 157

    • 802.11b Operating in a Mobile Channel: Performance and Challenges 

      Steger, Christopher; Radosavljevic, Predrag; Frantz, Patrick (2003-09-20)
      In the past, the worlds of wireless voice and data transmission have been largely disjoint. Voice traffic has been carried over circuit-switched cellular links, and data has been largely restricted to packet-switched ...
    • Adaptive Fault Detection and Tolerance for Robots 

      Visinsky, Monica L.; Cavallaro, Joseph R.; Walker, Ian D. (1994-08-01)
      In existing robot fault detection schemes, sensed values of the joint status (position, velocity, etc.) are typically compared against expected or desired values, and if a given threshold is exceeded, a fault is inferred. ...
    • Analysis of Robots for Hazardous Environments 

      Harpel, Barbara McLaughlin; Dugan, Joanne Bechta; Walker, Ian D.; Cavallaro, Joseph R. (1997-01-01)
      Reliability analysis of fault tolerant systems often ignores the small probability that a failure might not be detected or, if detected, may not be properly handled. The probability that the failure is detected and properly ...
    • Architecture and Algorithm for a Stochastic Soft-output MIMO Detector 

      Amiri, Kiarash; Radosavljevic, Predrag; Cavallaro, Joseph R. (2007-11-04)
      In this paper, we propose a novel architecture for a soft-output stochastic detector in multiple-input, multiple-output (MIMO) systems. The stochastic properties of this detector are studied and derived in this work, ...
    • Architecture and Algorithm for a Stochastic Soft-output MIMO Detector 

      Amiri, Kiarash; Radosavljevic, Predrag; Cavallaro, Joseph R. (2007-11-01)
      In this paper, we propose a novel architecture for a soft-output stochastic detector in multiple-input, multiple-output (MIMO) systems. The stochastic properties of this detector are studied and derived in this work, and ...
    • ARCHITECTURE DESIGN AND IMPLEMENTATION OF THE INCREASING RADIUS - LIST SPHERE DETECTOR ALGORITHM 

      Myllylä, Markus; Juntti, Markku; Cavallaro, Joseph R. (2009-04-01)
      A list sphere detector (LSD) is an enhancement of a sphere detector (SD) that can be used to approximate the optimal MAP detector. In this paper, we introduce a novel architecture for the increasing radius (IR)-LSD algorithm, ...
    • Architectures for Cognitive Radio Testbeds and Demonstrators – An Overview 

      Gustafsson, Oscar; Amiri, Kiarash; Andersson, Dennis; Blad, Anton; Bonner, Christian; Cavallaro, Joseph R.; Declerck, Jeroen; Dejonghe, Antoine; Eliardsson, Patrik; Glasse, Miguel; Hayar, Aawatif; Hollevoet, Lieven; Hunter, Chris; Joshi, Madhura; Kaltenberger, Florian; Knopp, Raymond; Le, Khanh; Miljanic, Zoran; Murphy, Patrick; Naessens, Frederik; Nikaein, Navid; Nussbaum, Dominique; Pacalet, Renaud; Raghavan, Praveen; Sabharwal, Ashutosh; Sarode, Onkar; Spasojevic, Predrag; Sun, Yang; Tullberg, Hugo M.; Vander Aa, Tom; Van der Perre, Liesbet; Wetterwald, Michelle; Wu, Michael (2010-06-01)
      Wireless communication standards are developed at an ever-increasing rate of pace, and significant amounts of effort is put into research for new communication methods and concepts. On the physical layer, such topics include ...
    • Arithmetic Acceleration Techniques for Wireless Communication Receivers 

      Das, Suman; Rajagopal, Sridhar; Sengupta, Chaitali; Cavallaro, Joseph R. (1999-10-20)
      We develop techniques to accelerate the implementation of the next generation wireless communication algorithms in hardware. We discuss an implementation of a key computationally intensive baseband algorithm for joint ...
    • ASIC Implementation Comparison of SIC and LSD Receivers for MIMO-OFDM 

      Ketonen, Johanna; Myllylä, Markus; Juntti, Markku; Cavallaro, Joseph R. (2008-10-01)
      MIMO-OFDM receivers with horizontal encoding are considered in this paper. The successive interference cancellation (SIC) algorithm is compared to the K-best list sphere detector (LSD). A modification to the K-best LSD ...
    • Automated Evaluation of Critical Features in VLSI Layouts Based on Photolithographic Simulations 

      Cavallaro, Joseph R.; Sengupta, Chaitali; Tittel, Frank K.; Wilson, William L. Jr. (1996-01-01)
      This paper describes a CAD tool (An Integrated CAD Framework) which links VLSI layout editors to lithographic simulators and provides information on the simulated resolution of a feature to the circuit designer. The designer ...
    • A bit-streaming pipelined multiuser detector for wireless communications 

      Rajagopal, Sridhar; Cavallaro, Joseph R. (2001-05-20)
      This paper presents a bit-streaming, pipelined and reduced complexity architecture to meet real-time requirements for asynchronous multiuser detection in wireless communication CDMA receivers. Typically, asynchronous ...
    • Compact Hardware Accelerator for Functional Verification and Rapid Prototyping of 4G Wireless Communication Systems 

      Guo, Yuanbin; McCain, Dennis (2004-11-01)
      In this paper, we propose an FPGA-based hardware accelerator platform with Xilinx Virtex-II V3000 in a compact PCMCIA form factor. By partitioning the complex algorithms in the 4G simulator to the hardware accelerator, ...
    • COMPARISON OF TWO NOVEL LIST SPHERE DETECTOR ALGORITHMS FOR MIMO-OFDM SYSTEMS 

      Myllylä, Markus; Silvola, Pirkka; Juntti, Markku; Cavallaro, Joseph R. (2006-09-01)
      In this paper, the complexity and performance of two novel list sphere detector (LSD) algorithms are studied and evaluated in multiple-input multiple-output orthogonal frequency division multiplexing (MIMO-OFDM) system. ...
    • Compiler Driven Architecture Design Space Exploration for DSP Workloads: A Study in Software Programmability Versus Hardware Acceleration 

      Brogioli, Michael C.; Cavallaro, Joseph R. (2009-11-01)
      Wireless communications and video kernels contain vast instruction and data level parallelism that can far outstrip programmable high performance DSPs. Hardware acceleration of these bottlenecks is commonly done at the ...
    • Complexity Analysis of MMSE Detector Architectures for MIMO OFDM Systems 

      Myllylä, Markus; Hintikka, Juha-Matti; Cavallaro, Joseph R.; Juntti, Markku; Limingoja, Matti; Byman, Aaron (2005-11-01)
      In this paper, a field programmable gate array (FPGA) implementation of a linear minimum mean square error (LMMSE) detector is considered for MIMO-OFDM systems. Two square root free algorithms based on QR decomposition ...
    • Configurable and Scalable High Throughput Turbo Decoder Architecture for Multiple 4GWireless Standards 

      Sun, Yang; Zhu, Yuming; Goel, Manish; Cavallaro, Joseph R. (2008-07-01)
      In this paper, we propose a novel multi-code turbo decoder architecture for 4G wireless systems. To support various 4G standards, a configurable multi-mode MAP (maximum a posteriori) decoder is designed for both binary and ...
    • CORDIC Arithmetic for an SVD Processor 

      Cavallaro, Joseph R.; Luk, Franklin T. (1987-05-01)
      Arithmetic issues in the calculation of the Singular Value Decomposition (SVD) are discussed. Traditional algorithms using hardware division and square root are replaced with the special purpose CORDIC algorithms for ...
    • Dataflow Modeling and Design for Cognitive Radio Networks 

      Wang, Lai-Huei; Bhattacharyya, Shuvra S.; Vosoughi, Aida; Cavallaro, Joseph R.; Juntti, Markku; Boutellier, Jani; Silven, Olli; Valkama, Mikko (2013-10-01)
      Cognitive radio networks present challenges at many levels of design including configuration, control, and crosslayer optimization. In this paper, we focus primarily on dataflow representations to enable flexibility and ...
    • Delay and Rate Constrained Transmission Policies over Wireless Channels 

      Rajan, Dinesh; Sabharwal, Ashutosh; Aazhang, Behnaam (2001-11-20)
      In this paper, we study delay and rate-constrained transmission of bursty traffic over wireless channels. We characterize the minimum power requirements via bounds for both single user and multiuser downlink problems, using ...
    • Delay-constrained Scheduling: Power Efficiency, Filter Design, and Bounds 

      Khojastepour, Mohammad; Sabharwal, Ashutosh (2004-03-01)
      In this paper, packet scheduling with maximum delay constraints is considered with the objective to minimize average transmit power over Gaussian channels. The main emphasis is on deriving robust schedulers which do ...