Now showing items 1-12 of 12

  • Constellations for Imperfect Channel State Information at the Receiver 

    Borran, Mohammad Jaber; Sabharwal, Ashutosh; Aazhang, Behnaam (2002-10-20)
    We consider the problem of digital communication in a Rayleigh flat fading environment using a multiple antenna system. We assume that the transmitter doesn't know the channel coefficients, and that the receiver has only ...
  • Design of Space Time Codes With Optimal Coding Gain 

    Mukkavilli, Krishna Kiran; Aazhang, Behnaam; Ionescu, Michael D. (2000-09-20)
    Space time codes have been proposed in the literature as an efficient means for improving the data rates over fading channels with multiple transmit antennas. In particular, the rank and the determinant of code difference ...
  • Design of space-time codes with optimal coding gain 

    Mukkavilli, Krishna Kiran; Ionescu, Michael D.; Aazhang, Behnaam (2000-10-20)
    Space time codes have been proposed in the literature as an efficient means for improving the data rates over fading channels with multiple transmit antennas. In particular, the rank and the determinant of code difference ...
  • Impact of Multiple Access on Uplink scheduling 

    Rajan, Dinesh; Sabharwal, Ashutosh; Aazhang, Behnaam (2001-09-20)
    In this paper, we consider uplink scheduling for bursty traffic. We characterize the achievable rate region for Gaussian multiple access in terms of minimum required powers, with a constraint on average transmission delay ...
  • On Channel State Information in Multiple Antenna Block Fading Channels 

    Sabharwal, Ashutosh; Erkip, Elza; Aazhang, Behnaam (2000-11-20)
    Motivated by large capacity gains in multiple antenna systems when perfect channel state information is available at both receiver and transmitter, we examine the achievable rates of channel measurement based techniques. ...
  • On Design Criteria and Construction of Non-coherent Space-Time Constellations 

    Borran, Mohammad Jaber; Sabharwal, Ashutosh; Aazhang, Behnaam (2003-10-20)
    We consider the problem of digital communication in a Rayleigh flat fading environment using a multiple-antenna system, when the channel state information is available neither at the transmitter nor at the receiver. It ...
  • On Design Criteria and Construction of Non-coherent Space-Time Constellations 

    Borran, Mohammad Jaber; Sabharwal, Ashutosh; Aazhang, Behnaam; Johnson, Don (2002-07-20)
    We consider the problem of digital communication in a Rayleigh flat fading environment using a multiple antenna system, when both the transmitter and the receiver are unaware of the channel coefficients. Using Stein's lemma ...
  • Partially Coherent Multiple Antenna Systems: Design Criterion and Construction Methods for Constellations and Coded Modulation 

    Borran, Mohammad Jaber; Sabharwal, Ashutosh; Aazhang, Behnaam (2004-01-15)
    We consider multiple-antenna communication systems in Rayleigh fading channel, where the transmitter does not know the channel coefficients and the receiver has only an estimate of them. We further assume that the transmitter ...
  • Power efficient transmission policies for multimedia traffic over wireless channels 

    Rajan, Dinesh (2002-04-20)
    The current and future wireless systems need to support a multitude of services with a wide range of data rates and reliability requirements. The limited battery resource at a mobile terminal coupled with the hostile ...
  • Power-Efficient Non-coherent Space-Time Constellations 

    Borran, Mohammad Jaber; Sabharwal, Ashutosh; Aazhang, Behnaam (2003-07-20)
    We consider the problem of digital communication in a Rayleigh flat-fading environment using a multiple-antenna system, when the channel state information is available neither at the transmitter nor at the receiver. It ...
  • A Recursive Construction for Low-Complexity Non-coherent Constellations 

    Borran, Mohammad Jaber; Sabharwal, Ashutosh; Aazhang, Behnaam (2004-04-01)
    It is known that at high signal to noise ratio (SNR), or for large coherence interval (T), a constellations of unitary matrices can achieve the capacity of the non-coherent multiple-antenna system in block Rayleigh flat-fading ...
  • Throughput Measures for Delay-constrained Communications in Fading Channels 

    Ahmed, Nadeem; Baraniuk, Richard G. (2003-10-01)
    Fading channels, often seen in wireless systems, provide an unfavorable environment for reliable communications. Current methods for evaluating the performance of fading channels include ergodic capacity and <i>epsilon</ ...