On Ergodic Sum Capacity of Fading Cognitive Multiple-Access and Broadcast Channels

By Rui Zhang, Shuguang Cui, Ying-Chang Liang. 2008

247 citations recorded by the source corpus.

This paper studies the information-theoretic limits of a secondary or cognitive radio (CR) network under spectrum sharing with an existing primary radio network. In particular, the fading cognitive multiple-access channel (C-MAC) is first studied, where multiple secondary users transmit to the secondary base station (BS) under both individual transmit-power constraints and a set of interference-power constraints each applied at one of the primary receivers. This paper considers the long-term (LT) or the short-term (ST) transmit-power constraint over the fading states at each secondary transmitter, combined with the LT or ST interference-power constraint at each primary receiver. In each case, the optimal power allocation scheme is derived for the secondary users to achieve the ergodic sum capacity of the fading C-MAC, as well as the conditions for the optimality of the dynamic time-division multiple-access (D-TDMA) scheme in the secondary network. The fading cognitive broadcast channel (C-BC) that models the downlink transmission in the secondary network is then studied under the LT/ST transmit-power constraint at the secondary BS jointly with the LT/ST interference-power constraint at each of the primary receivers. It is shown that D-TDMA is indeed optimal for achieving the ergodic sum capacity of the fading C-BC for all combinations of transmit-power and interference-power constraints.

Subfields: Computer Networks and Communications, Electrical and Electronic Engineering

How researchers see this paper

The researchers whose trusted networks rank it highest, strongest advocate first. Every researcher gets a different order.

In Computer Networks and Communications

  1. Rui Zhang
  2. Ying-Chang Liang
  3. Geoffrey Y. Li
  4. Kwang-Cheng Chen
  5. Tony Q. S. Quek
  6. Sang Hyun Lee
  7. Hoon Lee
  8. Xin Kang

In Electrical and Electronic Engineering

  1. Rui Zhang
  2. Ying-Chang Liang
  3. Tony Q. S. Quek
  4. Geoffrey Y. Li
  5. Sang Hyun Lee
  6. Hoon Lee
  7. Hyungsik Ju
  8. Kwang-Cheng Chen

Citations in the corpus