Journal ArticleDOI
Writing on dirty paper (Corresp.)
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It is shown that the optimal transmitter adapts its signal to the state S rather than attempting to cancel it, which is also the capacity of a standard Gaussian channel with signal-to-noise power ratio P/N.Abstract:
A channel with output Y = X + S + Z is examined, The state S \sim N(0, QI) and the noise Z \sim N(0, NI) are multivariate Gaussian random variables ( I is the identity matrix.). The input X \in R^{n} satisfies the power constraint (l/n) \sum_{i=1}^{n}X_{i}^{2} \leq P . If S is unknown to both transmitter and receiver then the capacity is \frac{1}{2} \ln (1 + P/( N + Q)) nats per channel use. However, if the state S is known to the encoder, the capacity is shown to be C^{\ast} =\frac{1}{2} \ln (1 + P/N) , independent of Q . This is also the capacity of a standard Gaussian channel with signal-to-noise power ratio P/N . Therefore, the state S does not affect the capacity of the channel, even though S is unknown to the receiver. It is shown that the optimal transmitter adapts its signal to the state S rather than attempting to cancel it.read more
Citations
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Journal ArticleDOI
Zero-forcing methods for downlink spatial multiplexing in multiuser MIMO channels
TL;DR: While the proposed algorithms are suboptimal, they lead to simpler transmitter and receiver structures and allow for a reasonable tradeoff between performance and complexity.
Journal ArticleDOI
Opportunistic beamforming using dumb antennas
TL;DR: This work shows that true beamforming gains can be achieved when there are sufficient users, even though very limited channel feedback is needed, and proposes the use of multiple transmit antennas to induce large and fast channel fluctuations so that multiuser diversity can still be exploited.
Book
Digital Watermarking
TL;DR: Digital Watermarking covers the crucial research findings in the field and explains the principles underlying digital watermarking technologies, describes the requirements that have given rise to them, and discusses the diverse ends to which these technologies are being applied.
Journal ArticleDOI
On the achievable throughput of a multiantenna Gaussian broadcast channel
Giuseppe Caire,Shlomo Shamai +1 more
TL;DR: Under certain mild conditions, this scheme is found to be throughput-wise asymptotically optimal for both high and low signal-to-noise ratio (SNR), and some numerical results are provided for the ergodic throughput of the simplified zero-forcing scheme in independent Rayleigh fading.
References
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Journal ArticleDOI
Achievable rates for multiple descriptions
Abbas El Gamal,Thomas M. Cover +1 more
TL;DR: These rates are shown to be optimal for deterministic distortion measures for random variables and Shannon mutual information.
Journal ArticleDOI
Multiple user information theory
A. El Gamal,Thomas M. Cover +1 more
TL;DR: A unified framework is given for multiple user information networks that consist of several users communicating to one another in the presence of arbitrary interference and noise and speculations about the form of a general theory of information flow in networks are offered.
Journal ArticleDOI
A proof of Marton's coding theorem for the discrete memoryless broadcast channel (Corresp.)
A. El Gamal,E.C. van der Meulen +1 more
TL;DR: A simple proof using random partitions and typicality is given for Marton's coding theorem for broadcast channels.