Now showing items 1-19 of 19

  • 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 ...
  • Computationally Efficient Iterative Multiuser Detection and Decoding 

    Das, Suman; Erkip, Elza; Aazhang, Behnaam (1998-11-20)
    We describe an iterative detection and decoding scheme for the uplink in a convolutionally coded direct sequence code division multiple access (DS-CDMA) system. We consider maximum-a-posteriori (MAP) decoding and reduce ...
  • Computationally Efficient Multiuser Detectors 

    Das, Suman; Cavallaro, Joseph R.; Aazhang, Behnaam (1997-09-20)
    CDMA is becoming an increasingly popular multiplexing scheme in wireless communications and this has necessitated the development of efficient detection techniques. The exponential complexity of the optimal detector on ...
  • Design of Computationally Efficient Multiuser Detectors for CDMA Systems 

    Das, Suman (1997-05-20)
    Linear multiuser detectors have been developed for CDMA systems to maintain a balance between the performance and computational complexity of the detectors. However for a system with a large number of users and huge data ...
  • Design of computationally efficient multiuser detectors for CDMA systems 

    Das, Suman (1997)
    Linear multiuser detectors have been developed for CDMA systems to maintain a balance between the performance and computational complexity of the detectors. However for a system with a large number of users and huge data ...
  • Distorted Channel Capacity: A Geometrical Approach 

    Das, Suman; Cavallaro, Joseph R.; Erkip, Elza; Aazhang, Behnaam (2000-06-20)
    Shannon's capacity result has often been used as a benchmark to compare the performance of practical codes. Shannon's theorem helps us to calculate the maximum rate at which data can be transferred without making any errors. ...
  • Efficient Multiuser Receivers for CDMA Systems 

    Sengupta, Chaitali; Das, Suman; Cavallaro, Joseph R.; Aazhang, Behnaam (1999-09-20)
    We focus on the design of multiuser receiver structures for Code Division Multiple Access (CDMA) communication systems, in the presence of multipath elects and multiple sensors at the base station receiver. We present a ...
  • Fast Multi-user Detector for a Time-varying CDMA System 

    Das, Suman; Cavallaro, Joseph R.; Aazhang, Behnaam (1997-07-01)
    This paper investigates methods to reduce the amount of computation needed to detect information bits using a linear detector for a CDMA system. We show windowing technique coupled with pipelining can reduce the amount of ...
  • Fixed Point Error Analysis Of Multiuser Detection and Synchronization Algorithms For CDMA Communication Systems 

    Sengupta, Chaitali; Das, Suman; Cavallaro, Joseph R.; Aazhang, Behnaam (1998-04-20)
    Conventional correlation based single-user techniques for Direct Sequence Code Division Multiple Access (DS-CDMA) wireless communication systems are susceptible to performance degradation due to interference from other ...
  • Hardware design issues for a mobile unit for next generation CDMA systems 

    Das, Suman; Sengupta, Chaitali; Cavallaro, Joseph R. (1998-07-20)
    This paper addresses hardware design issues of a mobile receiver for future generation direct sequence CDMA wireless communication systems. In the design of a mobile unit, fixed-point hardware is an attractive alternative ...
  • Iterative Multiuser Detection and Decoding 

    Das, Suman; Erkip, Elza; Cavallaro, Joseph R.; Aazhang, Behnaam (1998-11-20)
    An iterative detection and decoding algorithm is explored for a convolutionally coded DS-CDMA system. The optimum decoding strategy is to consider the trellises of all the users simultaneously, but this has exponential ...
  • Joint Multiuser Channel Estimation and Detection for CDMA Systems 

    Sengupta, Chaitali; Das, Suman; Cavallaro, Joseph R.; Aazhang, Behnaam (1999-02-20)
    We focus on the design of multiuser receiver structures for Code Division Multiple Access (CDMA) communication systems, in the presence of multipath effects and multiple sensors at the base station receiver. The joint ...
  • Low Complexity Iterative Multiuser Detection and Decoding for Real-Time Applications 

    Das, Suman; Erkip, Elza; Cavallaro, Joseph R.; Aazhang, Behnaam (2005-07-01)
    This paper presents a low-complexity multiuser decoding technique that can be implemented in real time for a convolutionally coded direct sequence code division multiple access (DS-CDMA) system. The main contribution, ...
  • Maximum Weight Basis Decoding of Convolutional Codes 

    Das, Suman; Erkip, Elza; Cavallaro, Joseph R.; Aazhang, Behnaam (2002-11-01)
    In this paper we describe a new suboptimal decoding technique for linear codes based on the calculation of maximum weight basis of the code. The idea is based on estimating the maximum number locations in a codeword which ...
  • Maximum Weight Basis Decoding of Convolutional Codes 

    Das, Suman; Erkip, Elza; Cavallaro, Joseph R.; Aazhang, Behnaam (2000-06-20)
    The effectiveness of the convolutional code increases with the constraint length of the code. Unfortunately the decoding complexity of Viterbi algorithm grows exponentially with the constraint length. In this paper we ...
  • Multiuser Information Processing in Wireless Communication 

    Das, Suman (2000-09-20)
    Wireless channel is not very conducive towards error-free raw data transmission. On the other hand the tremendous growth in wireless services has made the channel bandwidth a scarce resource and effective utilization of ...
  • Multiuser information processing in wireless communication 

    Das, Suman (2000)
    The available wireless bandwidth cannot keep pace with the amazing growth rate of wireless subscribers. Moreover, the higher data rate and superior quality of service demand of the increasingly popular multimedia services ...
  • Partially Blind Multiuser Detection 

    Das, Suman; Bhashyam, Srikrishna; Cavallaro, Joseph R.; Aazhang, Behnaam (1999-03-20)
    Multiple access interference (MAI) is a significant limiting factor in the performance of direct sequence code division multiple access (DS-CDMA) systems. Various multiuser detection techniques have been developed to combat ...
  • Partially Blind Multiuser Receivers for CDMA Systems 

    Das, Suman; Bhashyam, Srikrishna; Cavallaro, Joseph R.; Aazhang, Behnaam (1999-12-20)
    Multiple access interference (MAI) significantly limits the performance of code-division multiple access (CDMA) systems. Existing multiuser receivers combat MAI using the knowledge of either all (conventional) or none ...