Diversity-Multiplexing Tradeoff of Symmetric MIMO Interference Channels with Partial CSIT
ABSTRACT In this paper, we propose a transmission scheme for the two-user symmetric multiple antenna interference channel (IFC) and show that the proposed transmission scheme can achieve the optimal diversity-multiplexing tradeoff (DMT) of the channel. The proposed transmission scheme requires only limited channel state information at the transmitter (CSIT) and is suitable for practical implementation. The limited CSIT is obtained by letting the destinations quantize the required information and feed back to the sources. Rules for implementing the quantization are proposed and the number of bits needed to represent the quantization is calculated. It is shown that for the proposed transmission scheme to be DMT optimal, the number of feedback bits should increase in log scale with respect to signal-to-noise ratio.
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ABSTRACT: In this paper, diversity-multiplexing tradeoff (DMT) of the delay-limited symmetric two-user single-antenna fading interference channel (IFC) with source cooperation is evaluated under both full-duplex and half-duplex cooperation constraints. The interference signal and the desired signal received by each destination node are assumed to be of comparable strength. Under each cooperation constraint, DMT upper and lower bounds are derived and shown to be tight, i.e., the lower bound meets the upper bound. A full characterization of the DMT of the channel is thus established. The upper bounds are evaluated using the capacity upper bounds and the lower bounds are obtained based on our proposed transmission schemes. The proposed transmission schemes only require partial channel state information at transmitter side (CSIT), making them suitable for practical applications. Specifically, for the transmission scheme designed under the full-duplex constraint, the partial CSIT is obtained by letting each destination represent the fading magnitude of each of its incoming links using 1 bit of information and feed back this information to the sources. In the half-duplex case, the proposed transmission scheme requires no more than 3 bits of feedback information to represent the fading magnitude of each link. Our DMT results show that source cooperation can notably improve the system diversity performance over the whole multiplexing gain region even under the half-duplex constraint.IEEE Transactions on Information Theory 01/2011; 57:2781-2804. · 2.62 Impact Factor
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ABSTRACT: The diversity-multiplexing tradeoff (DMT) for interference networks, such as the interference channel, the X channel, the Z interference channel and the Z channel, is analyzed. In particular, we investigate the impact of rate-splitting and channel knowledge at the transmitters. We also use the DMT of the Z channel and the Z interference channel to distill insights into the "loud neighbor" problem for femto-cell networks. Comment: 5 pages05/2009;
Conference Proceeding: The diversity-multiplexing tradeoff of the symmetric MIMO 2-user interference channel[show abstract] [hide abstract]
ABSTRACT: The fundamental diversity-multiplexing tradeoff (DMT) of the quasi-static fading, symmetric 2-user MIMO interference channel (IC) with channel state information at the transmitters (CSIT) and a short term average power constraint is obtained. The general case is considered where the interference-to-noise ratio (INR) at each receiver scales differently from the signal-to-noise ratio (SNR) at the receivers. The achievability of the DMT is proved by showing that a simple Han-Kobayashi coding scheme can achieve a rate region which is within a constant (independent of SNR) number of bits from a set of upper bounds to the capacity region of the IC. In general, only part of the DMT curve with CSIT can be achieved by coding schemes which do not use any CSIT (No-CSIT). A result in this paper establishes a threshold for the INR beyond which the DMT with CSIT coincides with that with No-CSIT. Our result also settles one of the conjectures made in. Furthermore, the fundamental DMT of a class of non-symmetric ICs with No-CSIT is also obtained wherein the two receivers have different numbers of antennas.Information Theory Proceedings (ISIT), 2010 IEEE International Symposium on; 07/2010