Low-SNR capacity of noncoherent fading channels

Vignesh Sethuraman, Ligong Wang, Bruce Hajek, Amos Lapidoth

Research output: Contribution to journalArticlepeer-review


Discrete-time Rayleigh-fading single-input single-output (SISO) and multiple-input multiple-output (MIMO) channels are considered, with no channel state information at the transmitter or the receiver. The fading is assumed to be stationary and correlated in time, but independent from antenna to antenna. Peak-power and average-power constraints are imposed on the transmit antennas. For MIMO channels, these constraints are either imposed on the sum over antennas, or on each individual antenna. For SISO channels and MIMO channels with sum power constraints, the asymptotic capacity as the peak signal-to-noise ratio (SNR) goes to zero is identified; for MIMO channels with individual power constraints, this asymptotic capacity is obtained for a class of channels called transmit separable channels. The results for MIMO channels with individual power constraints are carried over to SISO channels with delay spread (i.e., frequency-selective fading).

Original languageEnglish (US)
Pages (from-to)1555-1574
Number of pages20
JournalIEEE Transactions on Information Theory
Issue number4
StatePublished - 2009


  • Channel capacity
  • Correlated fading
  • Frequencyselective fading
  • Low signal-to-noise ratio (SNR)
  • Multiple-input multiple-output (MIMO)

ASJC Scopus subject areas

  • Information Systems
  • Computer Science Applications
  • Library and Information Sciences

Fingerprint Dive into the research topics of 'Low-SNR capacity of noncoherent fading channels'. Together they form a unique fingerprint.

Cite this