Capacity Characterization for State-Dependent Gaussian Channel With a Helper

This paper studies a two-user state-dependent Gaussian multiple-access channel (MAC) with state noncausally known at one encoder. Two scenarios are considered: i) each user wishes to communicate an independent message to the common receiver, and ii) the two encoders send a common message to the receiver and the non-cognitive encoder (i.e., the encoder that does not know the state) sends an independent individual message (this model is also known as the MAC with degraded message sets).For both scenarios, new outer bounds on the capacity region are derived, which improve uniformly over the best known outer bounds. In the first scenario, the two corner points of the capacity region as well as the sum rate capacity are established, and it is shown that a single-letter solution is adequate to achieve both the corner points and the sum rate capacity. Furthermore, the full capacity region is characterized in situations in which the sum rate capacity is equal to the capacity of the helper problem. The proof exploits the optimal-transportation idea of Polyanskiy and Wu (which was used previously to establish an outer bound on the capacity region of the interference channel) and the worst-case Gaussian noise result for the case in which the input and the noise are dependent.

show abstract

“…1]. As observed in [11], the upper bound (91) is tight (i.e., C helper = C sum ) if P 1 ≤ 2.5, and the bound (92) is tight (i.e.,…”

Section: The Helper Problemmentioning

confidence: 64%

State-Dependent Gaussian Multiple Access Channels: New Outer Bounds and Capacity Results

Yang

Liang

Shamai

et al. 2018

IEEE Trans. Inform. Theory

Self Cite

View full text Add to dashboard Cite

show abstract

“…and R 2 = 1 2 log (|K 2 + I|) are achievable. For the point-to-point helper channel [28], it was shown that if the helper power is above some threshold, the state is completely canceled, whereas in our model we have two parallel channels. If the helper power is high enough, it can split its signal, similarly as for the Gaussian BC, such that one part of it is intended for Receiver 2, where by using dirty paper coding it eliminates completely the interference caused by the state and the part of the signal intended for Receiver 1.…”

Section: Theorem 3 the Channel Parametersmentioning

confidence: 83%

“…The best outer bound for the Gaussian MAC setting was recently reported in [26]. The point-to-point helper channel studied in [27,28] can be considered as a special case of [25], where the cognitive transmitter does not send any message. Further in [28], the state-dependent MAC with an additional helper was studied, and the partial/full capacity region was characterized under various channel parameters.…”

Section: P Smentioning

confidence: 99%

“…The point-to-point helper channel studied in [27,28] can be considered as a special case of [25], where the cognitive transmitter does not send any message. Further in [28], the state-dependent MAC with an additional helper was studied, and the partial/full capacity region was characterized under various channel parameters. Moreover, some state-dependent relay channel models can also be viewed as an extension of the state-dependent channel with a helper, where the relay serves the role of the helper by knowing the state information.…”

Section: P Smentioning

confidence: 99%

“…It was first introduced in [27], where the capacity in the infinite power regime was characterized and was shown to be achievable by lattice coding. The capacity under arbitrary state power was established for some special cases in [28]. Based on a single-bin GP binning scheme the following lower bound was derived for the discrete memoryless case…”

Section: P Smentioning

confidence: 99%

See 2 more Smart Citations

MIMO Gaussian State-Dependent Channels with a State-Cognitive Helper

Dikshtein

Duan

Liang

et al. 2019

Entropy

Self Cite

View full text Add to dashboard Cite

We consider the problem of channel coding over multiterminal state-dependent channels in which neither transmitters nor receivers but only a helper node has a non-causal knowledge of the state. Such channel models arise in many emerging communication schemes. We start by investigating the parallel state-dependent channel with the same but differently scaled state corrupting the receivers. A cognitive helper knows the state in a non-causal manner and wishes to mitigate the interference that impacts the transmission between two transmit–receive pairs. Outer and inner bounds are derived. In our analysis, the channel parameters are partitioned into various cases, and segments on the capacity region boundary are characterized for each case. Furthermore, we show that for a particular set of channel parameters, the capacity region is entirely characterized. In the second part of this work, we address a similar scenario, but now each channel is corrupted by an independent state. We derive an inner bound using a coding scheme that integrates single-bin Gel’fand–Pinsker coding and Marton’s coding for the broadcast channel. We also derive an outer bound and further partition the channel parameters into several cases for which parts of the capacity region boundary are characterized.

show abstract

Parallel Gaussian Channels Corrupted by Independent States With a State-Cognitive Helper

Dikshtein

Duan

Liang

et al. 2018

2018 IEEE International Conference on the Science of Electrical Engineering in Israel (ICSEE)

Self Cite

View full text Add to dashboard Cite

We consider a state-dependent parallel Gaussian channel with independent states and a common cognitive helper, in which two transmitters wish to send independent information to their corresponding receivers over two parallel subchannels. Each channel is corrupted by independent additive Gaussian state. The states are not known to the transmitters nor to the receivers, but known to a helper in a noncausal manner. The helper's goal is to assist a reliable communication by mitigating the state. Outer and inner bounds are derived and segments of the capacity region is characterized for various channel parameters. Index TermsDirty paper coding, Gel'fand-Pinsker scheme, noncausal channel state information, parallel channel.

show abstract

Capacity Characterization for State-Dependent Gaussian Channel With a Helper

Cited by 6 publications

References 21 publications

State-Dependent Gaussian Multiple Access Channels: New Outer Bounds and Capacity Results

State-Dependent Gaussian Multiple Access Channels: New Outer Bounds and Capacity Results

MIMO Gaussian State-Dependent Channels with a State-Cognitive Helper

Parallel Gaussian Channels Corrupted by Independent States With a State-Cognitive Helper

Contact Info

Product

Resources

About