The capacity of the Gaussian interference channel under strong interference (Corresp.)
TL;DR: The capacity region of a Gaussian interference channel with two separate messages is obtained for the case of moderately strong interference and it is shown that the region coincides with the one where both messages are required in both receiving terminals.
Abstract: The capacity region of a Gaussian interference channel with two separate messages is obtained for the case of moderately strong interference. It is shown that the region coincides with the one where both messages are required in both receiving terminals.
Citations
More filters
TL;DR: For the fully connected K user wireless interference channel where the channel coefficients are time-varying and are drawn from a continuous distribution, the sum capacity is characterized as C(SNR)=K/2log (SNR)+o(log( SNR), which almost surely has K/2 degrees of freedom.
Abstract: For the fully connected K user wireless interference channel where the channel coefficients are time-varying and are drawn from a continuous distribution, the sum capacity is characterized as C(SNR)=K/2log(SNR)+o(log(SNR)) . Thus, the K user time-varying interference channel almost surely has K/2 degrees of freedom. Achievability is based on the idea of interference alignment. Examples are also provided of fully connected K user interference channels with constant (not time-varying) coefficients where the capacity is exactly achieved by interference alignment at all SNR values.
3,385 citations
Cites background from "The capacity of the Gaussian interf..."
...926344 While less common in practice due to the complexity of multi-user detection, this approach is supported by the capacity results on the “very strong interference” [1], and “strong interference” [3], [4] scenarios in the context...
[...]
TL;DR: This paper describes the statistical models of fading channels which are frequently used in the analysis and design of communication systems, and focuses on the information theory of fading channel, by emphasizing capacity as the most important performance measure.
Abstract: In this paper we review the most peculiar and interesting information-theoretic and communications features of fading channels. We first describe the statistical models of fading channels which are frequently used in the analysis and design of communication systems. Next, we focus on the information theory of fading channels, by emphasizing capacity as the most important performance measure. Both single-user and multiuser transmission are examined. Further, we describe how the structure of fading channels impacts code design, and finally overview equalization of fading multipath channels.
2,017 citations
TL;DR: The capacity of the two-user Gaussian interference channel has been open for 30 years and the best known achievable region is due to Han and Kobayashi as mentioned in this paper, but its characterization is very complicated.
Abstract: The capacity of the two-user Gaussian interference channel has been open for 30 years. The understanding on this problem has been limited. The best known achievable region is due to Han and Kobayashi but its characterization is very complicated. It is also not known how tight the existing outer bounds are. In this work, we show that the existing outer bounds can in fact be arbitrarily loose in some parameter ranges, and by deriving new outer bounds, we show that a very simple and explicit Han-Kobayashi type scheme can achieve to within a single bit per second per hertz (bit/s/Hz) of the capacity for all values of the channel parameters. We also show that the scheme is asymptotically optimal at certain high signal-to-noise ratio (SNR) regimes. Using our results, we provide a natural generalization of the point-to-point classical notion of degrees of freedom to interference-limited scenarios.
1,473 citations
Posted Content•
TL;DR: This work shows that the existing outer bounds can in fact be arbitrarily loose in some parameter ranges, and by deriving new outer bounds, it is shown that a very simple and explicit Han-Kobayashi type scheme can achieve to within a single bit per second per hertz of the capacity for all values of the channel parameters.
Abstract: The capacity of the two-user Gaussian interference channel has been open for thirty years. The understanding on this problem has been limited. The best known achievable region is due to Han-Kobayashi but its characterization is very complicated. It is also not known how tight the existing outer bounds are. In this work, we show that the existing outer bounds can in fact be arbitrarily loose in some parameter ranges, and by deriving new outer bounds, we show that a simplified Han-Kobayashi type scheme can achieve to within a single bit the capacity for all values of the channel parameters. We also show that the scheme is asymptotically optimal at certain high SNR regimes. Using our results, we provide a natural generalization of the point-to-point classical notion of degrees of freedom to interference-limited scenarios.
1,210 citations
Cites background from "The capacity of the Gaussian interf..."
...interference channel In this case, the parameters of the Gaussian interference channel satisfy INR 1 ≥ SNR 2 and INR 2 ≥ SNR 1. The capacity region of the strong interference channel is already known [7]. In the following, we will show that we can get to within one bit of the capacity region of the Gaussian interference channel for both the weak interference channel and the mixed interference channel...
[...]
TL;DR: An achievable region which combines Gel'fand-Pinkser coding with an achievable region construction for the interference channel is developed, which resembles dirty-paper coding, a technique used in the computation of the capacity of the Gaussian multiple-input multiple-output (MIMO) broadcast channel.
Abstract: Cognitive radio promises a low-cost, highly flexible alternative to the classic single-frequency band, single-protocol wireless device. By sensing and adapting to its environment, such a device is able to fill voids in the wireless spectrum and can dramatically increase spectral efficiency. In this paper, the cognitive radio channel is defined as a two-sender, two-receiver interference channel in which sender 2 obtains the encoded message sender 1 plans to transmit. We consider two cases: in the genie-aided cognitive radio channel, sender 2 is noncausally presented the data to be transmitted by sender 1 while in the causal cognitive radio channel, the data is obtained causally. The cognitive radio at sender 2 may then choose to transmit simultaneously over the same channel, as opposed to waiting for an idle channel as is traditional for a cognitive radio. Our main result is the development of an achievable region which combines Gel'fand-Pinkser coding with an achievable region construction for the interference channel. In the additive Gaussian noise case, this resembles dirty-paper coding, a technique used in the computation of the capacity of the Gaussian multiple-input multiple-output (MIMO) broadcast channel. Numerical evaluation of the region in the Gaussian noise case is performed, and compared to an inner bound, the interference channel, and an outer bound, a modified Gaussian MIMO broadcast channel. Results are also extended to the case in which the message is causally obtained.
1,157 citations
Cites background from "The capacity of the Gaussian interf..."
...interference, as defined in [10], [23], and very-strong inte rference, as defined in [1], the capacity is known....
[...]
References
More filters
TL;DR: General bounds on the capacity region are obtained for discrete memoryless interference channels and for linear-superposition interference channels with additive white Gaussian noise.
Abstract: An interference channel is a communication medium shared by M sender-receiver pairs. Transmission of information from each sender to its corresponding receiver interferes with the communications between the other senders and their receivers. This corresponds to a frequent situation in communications, and defines an M -dimensional capacity region. In this paper, we obtain general bounds on the capacity region for discrete memoryless interference channels and for linear-superposition interference channels with additive white Gaussian noise. The capacity region is determined in special cases.
804 citations
TL;DR: In this paper, it was shown that under certain conditions, two strongly interfering communication links with additive white Gaussian noise can achieve rates as high as would be achievable without this interference.
Abstract: It is shown that, under certain conditions, two strongly interfering communication links with additive white Gaussian noise can achieve rates as high as would be achievable without this interference.
669 citations
TL;DR: In this paper, a characterization of the capacity region of a two-way channel is given for the communication situation, in which both senders send independent messages simultaneously to both receivers and all senders and receivers are at different terminals.
Abstract: A characterization of the capacity region of a two-way channel is given for the communication situation, in which both senders send independent messages simultaneously to both receivers and all senders and receivers are at different terminals.
394 citations
TL;DR: Degraded two-user channels are introduced and studied in detail; in particular, an achievable region is obtained by combining two regions that correspond to the two different modes of transmission.
Abstract: A discrete memoryless channel with two inputs and two outputs, called a two-user channel, is studied under the communication situation where only separate messages are allowed to be sent between two source-user pairs. An outer bound to the capacity region is obtained by a method similar to that used by the author for the broadcast channel. Two extreme cases of two-user channels are discussed: separate channels and incompatible channels. Degraded two-user channels are introduced and studied in detail; in particular, an achievable region is obtained by combining two regions that correspond to the two different modes of transmission. This idea is extended to the general two-user channel where an achievable region for the general channel is obtained by random coding arguments.
240 citations