Broadcasting correlated Gaussians

2011 12th Canadian Workshop on Information Theory

2011

We study hybrid digital-analog (HDA) joint sourcechannel coding schemes in transmitting an analog Gaussian source over an AWGN channel in the presence of an interference, correlated with the source. We analyze these schemes to obtain achievable (mean-squared error) distortion-power tradeoffs. For comparison, we also obtain two outer bounds for the achievable distortion-power tradeoff; those are two necessary conditions under which (D, P ) is achievable. Using numerical examples, we demonstrate that, a two-layered coding scheme consisting of analog and Costa coding performs well compared to other provided HDA schemes.

“…Similarly in [27], [28], [29], by assuming the knowledge of one of the sources at the receiver of the strong user, outer bounds for broadcasting correlated Gaussian sources are developed.…”

Section: B Outer Bound IImentioning

confidence: 99%

On the transmission of a Gaussian source over an AWGN channel with correlated interference

Varasteh

2011 12th Canadian Workshop on Information Theory

2011

“…By comparing (8) and (11), we observe that the only difference is in the denominator. The lower bound of (8) is in the form D`= D …”

Section: A Lower Boundmentioning

confidence: 99%

“…The minimum achievable distortion under a sum-power constraint for the uncoded transmission scheme in the WSN with deterministic fading is presented in [6]. The optimality of uncoded transmission in some other multiuser communication systems was recently shown in [7] and [8].…”

Section: Introductionmentioning

confidence: 99%

On the Optimal Performance in Asymmetric Gaussian Wireless Sensor Networks With Fading

IEEE Trans. Signal Process.

Alajaji

Linder

2010

Abstract-We study the estimation of a Gaussian source by a Gaussian wireless sensor network (WSN) where distributed sensors transmit noisy observations of the source through a fading Gaussian multiple access channel to a fusion center. In a recent work Gastpar, ["Uncoded transmission is exactly optimal for a Simple Gaussian Sensor Network," IEEE Trans. Inf. Theory, vol. 54, no. 11, pp. 5247-5251, Nov. 2008] showed that for a symmetric Gaussian WSN with no fading, uncoded (analog) transmission achieves the optimal performance theoretically attainable (OPTA). In this correspondence, we consider an asymmetric fading WSN in which the sensors have differing noise and transmission powers. We first present lower and upper bounds on the system's OPTA under random fading. We next focus on asymmetric networks with deterministic fading. By comparing the obtained lower and upper OPTA bounds under deterministic fading, we provide a sufficient condition for the optimality of the uncoded transmission scheme for a given power tuple = ( . . . ).Then, allowing the sensor powers to vary under a weighted sum constraint (this includes the sum-power constraint as a special case), we obtain a sufficient condition for the optimality of uncoded transmission and provide the system's corresponding OPTA.Index Terms-Gaussian multiple access channel with fading, joint source-channel coding, power-distortion tradeoff, remote source coding, sensor networks, uncoded transmission.

“…Comparing (27) with (8) reveals that this VQ-based JSCC scheme is optimal in the sense of achieving OPTA. In other words, as the quantization dimension tends to infinity, this JSCC scheme is optimal if we choose the rate of the vector quantizer arbitrarily close to the capacity of the fading channel.…”

Section: A Vq-based Jscc With Dcsimentioning

confidence: 99%

“…For the point-to-point transmission of a single Gaussian source through an AWGN channel it is known (e.g., see [5], [4]) that if the channel bandwidth is equal to the source bandwidth, a simple uncoded transmission, which can be regarded as a special case of JSCC, achieves OPTA. The optimality of uncoded transmission in some multi-user communication systems was recently shown in [6], [7], [8]. Furthermore in [1], it is shown that uncoded transmission cannot achieve OPTA in the presence of fading.…”

Section: Introductionmentioning

confidence: 97%

On the transmission of a memoryless Gaussian source over a memoryless fading channel

2008 24th Biennial Symposium on Communications

Haghighat

Alajaji

et al. 2008

We consider the transmission of a discrete memoryless Gaussian source over a discrete memoryless fading channel with additive white Gaussian noise (AWGN) where the decoder has perfect channel state information (CSI). Our goal is to characterize the optimal tradeoff between the average transmission power constraint, P and the average estimation distortion, D. It is well known that for point-to-point transmission of a single Gaussian source over an AWGN channel, if the channel bandwidth is equal to the source bandwidth, linear (scalar) joint source-channel coding, i.e., uncoded transmission, achieves the optimal power-distortion tradeoff (Shannon's limit). But this result does not hold in the presence of fading [1]. In this work, we show that a relatively simple joint sourcechannel coding scheme, proposed by Lapidoth et al., which is based on the transmission of scaled versions of vector-quantized source sequences, can approach the optimal power-distortion tradeoff. This coding scheme is still optimal when the CSI is available at both the encoder and the decoder.