Showing papers on "Dirty paper coding published in 2016"
TL;DR: It is figured out that the proposed NOMA scheme can approach nearly the same performance as optimal dirty paper coding, as verified by computer simulations.
Abstract: In this letter, based on the non-orthogonal multiple access (NOMA) concept, a quality-of-service optimization problem for two-user multiple-input-single-output broadcast systems is considered, given a pair of target interference levels. The minimal power and the optimal precoding vectors are obtained by considering its Lagrange dual problem and via Newton’s iterative algorithm, respectively. Moreover, the closed-form expressions of the minimal transmission power for some special cases are also derived. One of these cases is termed quasi-degraded, which is the key point and will be discussed in detail in this letter. Our analysis further figures out that the proposed NOMA scheme can approach nearly the same performance as optimal dirty paper coding, as verified by computer simulations.
106 citations
TL;DR: The locally optimal scheduling of the transmission modes over time is derived and the achievable average rate is investigated, when the relays are affected by inter-relay interference.
Abstract: A simple diamond half-duplex relay network composed of a source, two decode-and-forward half-duplex relays, and a destination is considered, where a direct link between the source and the destination does not exist. For this network, we study the case of buffer-aided relays, where the relays are equipped with buffers. Each relay can receive data from the source, store it in the buffer, and forward it to the destination, when the channel conditions are advantageous. Thereby, buffering enables adaptive scheduling of the transmissions and receptions over time, which allows the network to exploit the diversity offered by the fading channels. For the considered half-duplex network, four transmission modes are defined based on whether the relay nodes receive or transmit. In this paper, we derive the locally optimal scheduling of the transmission modes over time and investigate the achievable average rate, when the relays are affected by inter-relay interference. Since the proposed buffer-aided transmission policies introduce unbounded delay, we provide a sub-optimal buffer-aided transmission policy with limited delay. Moreover, for inter-relay interference cancellation, we consider two coding schemes with different complexities. In the first scheme, we employ dirty paper coding, which entails a high complexity, whereas in the second scheme, we adopt a low-complexity technique based on successive interference cancellation at the receiving relay nodes and optimal power allocation at the transmitting nodes. Our numerical results show that the proposed protocols, with and without delay constraints, outperform existing protocols for the considered network from the literature.
35 citations
TL;DR: A novel user grouping precoder is proposed which improves the sum rate performance of the zero-forcing (ZF) precoder specially when the channel is ill-conditioned and allows for tradeoff between performance and complexity.
Abstract: We consider the multiple input single output (MISO) Gaussian broadcast channel with $N_t$ antennas at the base station (BS) and $N_u$ single-antenna users in the downlink. We propose a novel user grouping precoder which improves the sum rate performance of the zero-forcing (ZF) precoder specially when the channel is ill-conditioned. The proposed precoder partitions all the users into small groups of equal size. Downlink beamforming is then done in such a way that, at each user’s receiver, the interference from the signal intended for users not in its group is nulled out. Intragroup interference still remains, and is cancelled through successive interference presubtraction at the BS using dirty paper coding (DPC). The proposed user grouping method is different from user selection, since it is a method for precoding of information to the selected (scheduled) users, and not for selecting which users are to be scheduled. The proposed precoder is a generalization of two special cases, one where each group has only one user (ZF precoder) and another where all users are in a single group (ZF-DP precoder). A larger group size helps improve the sum rate performance but at the cost of greater complexity. The proposed generalization, therefore, allows for tradeoff between performance and complexity.
23 citations
TL;DR: Comparison between the state-dependent regular IC and the Z-IC suggests that even with one interference-free link, theZ-IC does not necessarily perform better, because dirty paper coded interference in the regular IC facilitates to cancel the state through the cooperative dirty paper coding between the transmitters.
Abstract: The state-dependent Gaussian interference channel (IC) and Z-IC are investigated, in which two receivers are corrupted by the same but differently scaled states. The state sequence is noncausally known at both transmitters, but not known at either receiver. Three interference regimes are studied, i.e., the very strong, strong, and weak regimes. In the very strong regime, the capacity region is characterized under certain channel parameters by designing a cooperative dirty paper coding between the two transmitters to fully cancel the state. In the strong regime, points on the capacity region boundary are characterized under certain channel parameters by designing an achievable scheme based on rate splitting, layered dirty paper coding, and successive state cancellation. In the weak regime, the sum capacity is obtained by independent dirty paper coding at two transmitters. For all the above regimes, the capacity achieves that of the IC/Z-IC without state. Comparison between the state-dependent regular IC and the Z-IC suggests that even with one interference-free link, the Z-IC does not necessarily perform better, because dirty paper coded interference in the regular IC facilitates to cancel the state through the cooperative dirty paper coding between the transmitters.
9 citations
TL;DR: The general case with arbitrary state power is explored, in which a transmitter communicates with a receiver via a state-corrupted channel and a lower bound on the capacity is derived based on an achievable scheme that integrates direct state subtraction and single-bin dirty paper coding.
Abstract: The state-dependent point-to-point Gaussian channel with a helper is first studied, in which a transmitter communicates with a receiver via a state-corrupted channel. The state is not known to the transmitter nor to the receiver, but known to a helper noncausally, which then wishes to assist the receiver to cancel the state. Differently from the previous work that characterized the capacity only in the infinite state power regime, this paper explores the general case with arbitrary state power. A lower bound on the capacity is derived based on an achievable scheme that integrates direct state subtraction and single-bin dirty paper coding. By analyzing this lower bound and further comparing it with the existing upper bounds, the capacity of the channel is characterized for a wide range of channel parameters. Such an idea of characterizing the capacity is further extended to study the two-user state-dependent multiple access channel with a helper. By comparing the derived inner and outer bounds, the channel parameters are partitioned into appropriate cases, and for each case, either segments on the capacity region boundary or the full capacity region are characterized.
8 citations
19 May 2016
TL;DR: These compares the method of transmission for broadcast channel (BC) and propose the best one method that outperforms existing technique with percentage improvement from the worst performance.
Abstract: Multiple Input Multiple Output (MIMO) system has been brought a great improvement in spectral efficiency and the system capacity by serving multiple users simultaneously. The mathematical model of downlink Multi-user MIMO system and its capacity has been presented as well as different precoded transmission schemes. It is to implementing the downlink MU-MIMO system, such as channel inversion (CI), block diagonalization (BD), dirty paper coding (DPC) and tomlinsonharashimaprecoding (THP). It is because, in wireless and mobile communication system has been requires a reliable transmission of high data rates under various channel type different scenarios and reduce MU interference in the system. These compares the method of transmission for broadcast channel (BC) and propose the best one method that outperforms existing technique with percentage improvement from the worst performance.
5 citations
01 Jan 2016
TL;DR: This chapter presents a functional view of a watermarking scheme (the embedding function, the decoding/detection function and then its geometrical interpretation), and presents the most popular class of watermarked schemes: spread-spectrum water marking and watermarker techniques based on the idea of dirty paper codes.
Abstract: In order to understand and analyse the main components of watermarking security presented in the next chapters, we introduce in this chapter the different elements needed to embed a watermark or a message inside a host content. We first present a functional view of a watermarking scheme (the embedding function, the decoding/detection function) and then its geometrical interpretation. Then we present the most popular class of watermarking schemes: spread-spectrum watermarking and watermarking techniques based on the idea of dirty paper codes.
5 citations
TL;DR: It is demonstrated that BD is possible in frequency-selective MIMO broadcast channels to eliminate inter-user interference and derive the conditions on the number of transmit antennas and the transmission block length for the existence of BD precoders, and any transmit-processing-only method yields zero diversity and multiplexing gains (high SNR regime).
Abstract: The most important linear precoding method for frequency-flat MIMO broadcast channels is block diagonalization (BD) which, under certain conditions, attains the same nonlinear dirty paper coding channel capacity. However, BD is not easily translated to frequency-selective channels, since space-time information must be included in the transceiver design. In this paper, we demonstrate that BD is possible in frequency-selective MIMO broadcast channels to eliminate inter-user interference and derive the conditions on the number of transmit antennas and the transmission block length (as functions of the number of users and channel delay spread) for the existence of BD precoders. We also propose three different approaches to mitigate/eliminate inter-symbol interference in block transmissions: time-reversal-based BD (TRBD), equalized BD (EBD), and joint processing BD (JPBD). We show that any transmit-processing-only method (including TRBD and EBD) yields zero diversity and multiplexing gains (high SNR regime). We also demonstrate that JPBD, which uses linear processing at the transmitter and the receiver, approximates full multiplexing gain for a sufficiently large transmit block length, and show its diversity-multiplexing tradeoff. Extensive numerical simulations show that the achievable rate and probability of error performance of all the proposed techniques remarkably improve that of conventional time-reversal beamforming. Moreover, JPBD provides the highest achievable rate region for frequency-selective MIMO broadcast channels.
4 citations
TL;DR: The proposed algorithm based on non-linear precoding achieves about 20 percent performance gains over the conventional linear precoding method for weighted sum energy efficiency for a multi-cell multi-user channel.
Abstract: In this paper, we focus on maximizing weighted sum energy efficiency (EE) for a multi-cell multi-user channel. In order to solve this non-convex problem, we first decompose the original problem into a sequence of parallel subproblems which can optimized separately. For each subproblem, a base station employs dirty paper coding to maximize the EE for users within a cell while regulating interference induced to other cells. Since each sub-problem can be transformed to a convex multiple-access channel problem, the proposed method provides a closed-form solution for power allocation. Then, based on the derived optimal covariance matrix for each subproblem, a local optimal solution is obtained to maximize the sum EE. Finally, simulation results show that our algorithm based on non-linear precoding achieves about 20 percent performance gains over the conventional linear precoding method.
4 citations
Posted Content•
TL;DR: In this article, the authors demonstrate that block diagonalization (BD) is feasible in frequency-selective MIMO broadcast channels to eliminate inter-user interference (IUI) if the transmit block length is sufficiently large, and if the number of transmit antennas is greater than the total number of users.
Abstract: The most relevant linear precoding method for frequency-flat MIMO broadcast channels is block diagonalization (BD) which, under certain conditions, attains the same nonlinear dirty paper coding channel capacity. However, BD is not easily translated to frequency-selective channels, since space-time information is required for transceiver design. In this paper, we demonstrate that BD is feasible in frequency-selective MIMO broadcast channels to eliminate inter-user interference (IUI) if the transmit block length is sufficiently large, and if the number of transmit antennas is greater than the number of users. We also propose three different approaches to mitigate/eliminate inter-symbol interference (ISI) in block transmissions: i) time-reversal-based BD (TRBD) which maximizes spatial focusing around the receivers using transmitter processing only, ii) equalized BD (EBD) which minimizes the ISI using transmitter processing only, and iii) joint processing BD (JPBD), which uses linear processing at the transmitter and the receiver to suppress ISI. We analyze the theoretical diversity and multiplexing gains of these techniques, and we demonstrate that JPBD approximates full multiplexing gain for a sufficiently large transmit block length. Extensive numerical simulations show that the achievable rate and probability of error performance of all the proposed methods improve those of conventional time-reversal beamforming. Moreover, JPBD provides the highest achievable rate region for frequency-selective MIMO broadcast channels.
4 citations
30 Mar 2016
TL;DR: In MU-MIMO WLAN settings, analytical and numerical studies show that, with an increasing number of antennas at the clients, both the quantization error bound and the average rate reduction increase for ZFQ, in comparison to the ZFB with the perfect CSI.
Abstract: In Multi-User Multiple Input Multiple Output (MU-MIMO) Wireless Local Area Networks (WLANs), the optimal-solution such as Dirty Paper Coding (DPC) or the sub-optimal solution Zeroforcing Beamforming (ZFB) with perfect Channel State Information (CSI), is practically limited due to the complexity and the non-availability of perfect CSI at the Access Points (APs)/transmitters. In such a context, ZFB based on channel quantization available at the APs (ZFQ) is the obvious choice for the Multi-User transmission strategy. However, since the quantized CSI is used instead of the perfect CSI at the APs, the quantization error and its impact on the average rate for ZFQ have to be quantified in MU-MIMO WLAN settings. In this paper, we derive a closed-form expression for the upper bound of the channel quantization error and the average rate reduction due to the quantization error with respect to the perfect CSI at the APs. In MU-MIMO WLAN settings, our analytical and numerical studies show that, with an increasing number of antennas at the clients, both the quantization error bound and the average rate reduction increase for ZFQ, in comparison to the ZFB with the perfect CSI.
17 Mar 2016
TL;DR: A modified dirty paper coding technique to mitigate the effect of inter-cell interference is introduced and results shows that sum rate of Modifieddirty paper coding is 23% more than Zero-Forcing technique.
Abstract: The major challenge in Long Term Evolution Advanced (LTE-A) based 5G network is to improve the cell capacity and cell coverage of indoor users. To fulfill these demands, low power Femto Base stations are deployed at homes and company premises. Such heterogeneous network introduces interference due to both Femtocell and microcell users, especially for cell edge users as the frequencies are reused intrusively. In this Paper, we are introduce a modified dirty paper coding technique to mitigate the effect of inter-cell interference. To reduce the effect of interference, each user feedback quantize CSI to base station and then appropriate precoding is done on transmitted signal. Here, we are compare the sum rate of the Modified Dirty Paper Coding and Zero-Forcing technique. Simulation results shows that sum rate of Modified dirty paper coding is 23% more than Zero-Forcing technique.
01 Dec 2016
TL;DR: This paper demonstrates that block diagonalization is feasible in frequency- selective channels when the transmitted block length is sufficiently large and the number of transmit antennas is greater than or equal to thenumber of users and presents three novel techniques based on BD for frequency-selective MU- MIMO systems.
Abstract: The capacity of frequency-flat multiuser MIMO downlinks is achieved with nonlinear dirty paper coding (DPC). Linear processing techniques, such as block diagonalization (BD), offer relatively low computational cost with respect to DPC and can also achieve capacity in certain cases. However, BD is not easily translated to frequency-selective channels since the channel matrix has a space-time structure (unlike the space-only information in frequency-flat channels), which induces an additional inter-symbol interference (ISI) component in the received signal. In this paper, we demonstrate that BD is feasible in frequency- selective channels when the transmitted block length is sufficiently large and the number of transmit antennas is greater than or equal to the number of users. We also present three novel techniques based on BD for frequency-selective MU- MIMO systems: time-reversal-based BD (TRBD), equalized BD (EBD), and joint processing BD (JPBD). These techniques use perfect channel state information at the transmitter (and also at the receiver, in the case of JPBD) to mitigate or eliminate both ISI and inter-user interference. We demonstrate that TRBD and EBD yield zero multiplexing gain (high SNR regime) but perform well under low SNR, while JPBD has a multiplexing gain approximately equal to the number of users for a sufficiently large transmit block length. Extensive numerical simulations show that the achievable rate performance of the proposed techniques improves that of time-reversal beamforming, a common technique for frequency- selective MU-MIMO downlinks.
01 Sep 2016
TL;DR: Results indicate that the proposed cross-layered cooperative scheme is proposed in an interference channel with cooperation between transmitters leading to significant improvements in the cell-edge throughput.
Abstract: In this paper, a cross-layered cooperative scheme is proposed in an interference channel with cooperation between transmitters leading to significant improvements in the cell-edge throughput. Considering the problem of resource allocation in a cooperative scenario, the two-step scheme was proposed: In PHY layer, a dirty paper coding based transmit scheme with private information sharing is proposed in order to enlarge the achievable rate region. In MAC layer, a novel cooperative transmitter scheduling scheme is proposed in which the set of cooperative is adapted according to the variation in channel conditions. The heuristic algorithm is proposed to overcome the two-step-problem efficiently. Simulation to demonstrate the performance of the proposed algorithm has been carried out and the results indicate that the proposed scheme enhance the throughput significantly.
20 Mar 2016
TL;DR: This paper proposes a hybrid secure transmission scheme which combines zero-forcing DPC and artificial noise (AN) and finds that in addition to supporting the normal transmission, the proposed scheme has the potential to achieve a secrecy rate close to that of the traditional AN-based beamforming.
Abstract: This paper studies the dirty-paper coding (DPC) based secure transmission in a multiuser broadcast channel. Since the encoding order of DPC determines which information-bearing signals must be treated as noise by potential eavesdroppers, adopting DPC enables the accurate characterization of the intrinsic secrecy as well as secrecy outage of multiuser broadcasting. Furthermore, the information-bearing signals can be designed to provide secrecy in addition to supporting normal (unclassified) transmission. To show this, we consider the scenario where one user requests secure transmission and the other users request normal transmission, and propose a hybrid secure transmission scheme which combines zero-forcing DPC and artificial noise (AN). By solving the secrecy rate maximization problem under constraints on the secrecy outage probability and the normal communication rates, we find that in addition to supporting the normal transmission, the proposed scheme has the potential to achieve a secrecy rate close to that of the traditional AN-based beamforming.
01 Oct 2016
TL;DR: It is shown that having as many active beams as the number of transmit antennas is not always optimal for sparse network, thus scheduling strategies for ORBF with beam selection is investigated and several user-beam selection algorithms feature different complexity levels and their performance in terms of secrecy sum-rate is assessed.
Abstract: This paper studies the downlink of a wireless system with an M-antenna base station, K single-antenna legitimate users and a single-antenna eavesdropper. A limited feedback-based scheduling and precoding scenario is considered that employs the orthogonal random beamforming (ORBF). The sum-rate of ORBF exhibits an identical growth rate as that of dirty paper coding for a large number of users. Unfortunately, for more realistic (low to moderate) K values, ORBF yields degraded performance. It is shown that having as many active beams as the number of transmit antennas is not always optimal for sparse network, thus scheduling strategies for ORBF with beam selection is investigated. Several user-beam selection algorithms featuring different complexity levels are proposed and their performance in terms of secrecy sum-rate is assessed. Numerical results are provided to illustrate the impact of the number of active beams on the secrecy performance.
01 Nov 2016
TL;DR: A simplified expression is obtained for the exact difference in sum rate between DPC and ZFBF at all SNRs, and a significant improvement in rate in wideband OFDM transmission by using DPC for only a small fraction of subcarriers is shown.
Abstract: Consider a two-user MIMO Gaussian Broadcast Channel with two antennas at the transmitter and two single-antenna receivers. While Dirty Paper Coding (DPC) achieves capacity, its practical adoption needs a precise comparison with the popular method of Zero Forcing Beam Forming (ZFBF). In this work, we obtain a simplified expression for the exact difference in sum rate between DPC and ZFBF at all SNRs. Using this expression, we obtain the distribution of the difference under block fading, and show a significant improvement in rate in wideband OFDM transmission by using DPC for only a small fraction of subcarriers.
Posted Content•
TL;DR: This report analyzes the proposed method, named Dirty Paper-based Channel Estimation (DPCE), when the considered codebooks are high-dimensional lattices, and derivations on a channel estimation method based on the use of Dirty Paper Coding are included.
Abstract: In this report we include some derivations on a channel estimation method based on the use of Dirty Paper Coding. Specifically, we analyze the proposed method, named Dirty Paper-based Channel Estimation (DPCE), when the considered codebooks are high-dimensional lattices.
TL;DR: This paper finds the most suitable outer convolutional code (CC) for VP precoded transmission under bit-interleaved coded modulation with iterative decoding (BICM-ID) by applying a semi-analytic technique based on extrinsic information transfer charts.
Abstract: This paper proposes a channel code for vector perturbation (VP) precoded transmission in multiuser downlink and examines its achievable sum-rate performance. In particular, we first find the most suitable outer convolutional code (CC) for VP precoded transmission under bit-interleaved coded modulation with iterative decoding (BICM-ID) by applying a semi-analytic technique based on extrinsic information transfer charts. We then study the achievable sum rate of the proposed BICM-ID-based VP precoded system, and we compare it with the sum capacity of the dirty paper coding (DPC) scheme. Our investigation shows that under perfect channel state information (CSI), the sum rate of the proposed system grows linearly over the number of users, which is the same growth of the DPC. Under quantized CSI and finite-rate feedback, a linear increase in feedback overhead per user is necessary to maintain such a linear sum-rate growth.
01 Sep 2016
TL;DR: This paper discusses the coding schemes when one SU and two SUs are in the CRN, and formulates the corresponding system optimization problem, which maximizes the secondary rate while satisfying the primary rate requirement.
Abstract: Compressive sensing (CS) is an emerging theory in that it is possible to reconstruct sparse signals from far fewer measurements than traditional methods use. Existing studies utilizing CS in the field of cognitive radio network (CRN) mainly focus on spectrum sensing in interweave mode. However, few works concern about the application of CS in overlay CRNs. In this paper, we study the overlay CRN, which applies CS technology as a joint source-channel code. The secondary user (SU) not only sends its own message, but also employs decode-and-forward relaying strategy to help with primary transmission, where the primary message is obtained in a causal manner. Dirty paper coding is used to pre-cancel the interference of the primary message at the secondary receiver. We discuss the coding schemes when one SU and two SUs are in the CRN. To either case, we formulate the corresponding system optimization problem, which maximizes the secondary rate while satisfying the primary rate requirement. The performance of the proposed scheme is evaluated by numerical simulations and compared with the nonoptimal causal scheme and the non-causal scheme.
TL;DR: A symbol-by-symbol precoding scheme is developed for M-PAM SS embedding to alleviate the impact of the interference which is explicitly known to embedder.
Abstract: We consider M-level pulse amplitude modulation (M-PAM) spread-spectrum (SS) data embedding in transform domain host data. The process of data embedding can be viewed as delivering information through the channel including additive interference from host that is known to the embedder. We first utilize the knowledge of second-order statistics of host to design optimal carrier that maximizes the signal-to-interference-plus-noise ratio at the decoder end. Then, inspired by Tomlinson---Harashima precoding used in communication systems, a symbol-by-symbol precoding scheme is developed for M-PAM SS embedding to alleviate the impact of the interference which is explicitly known to embedder. For any given embedding carrier and host data, we aim at designing precoding algorithm to minimize the receiver bit error rate (BER) with any given host distortion budget, and conversely minimize the distortion at any target BER. Experimental studies demonstrate that the proposed precoded SS embedding approach can significantly improve BER performance over conventional SS embedding schemes.
01 Mar 2016
TL;DR: It is proved that Costa's dirty paper coding is optimal like lattice strategies and therefore, the Gaussian doubly dirty TWC is an instance of multi‐user channels in which lattice strategy and Costa's strategy have the same performance from the capacity region perspective.
Abstract: In this paper, we characterize capacity region of the Gaussian doubly dirty two-way channel TWC with partial side information at users, where there are two additive interference signals that, although similar to the channel noise sequences, corrupt the transmitted signals but are non-causally and partially known to the users. First, by employing adaptation considering the previously received signals in encoding process, we derive an adaptive outer bound on the capacity region of the channel. Then, we utilize lattice strategies and obtain a non-adaptive inner bound that coincides with the adaptive outer bound and hence gives the capacity region. This also shows that for the doubly dirty TWC with partial side information, adaptation is useless and cannot increase the capacity region. Finally, we prove that Costa's dirty paper coding is optimal like lattice strategies and therefore, the Gaussian doubly dirty TWC is an instance of multi-user channels in which lattice strategy and Costa's strategy have the same performance from the capacity region perspective. It is worth noting that our results subsume the previous related works as special cases. Copyright © 2014 John Wiley & Sons, Ltd.
TL;DR: MSE: minimum mean-squared error (MMSE) 기반한 프리코딩(precoding) 하향링크 채널에서 최소평균제곱오차(MMSE).
Abstract: 본 논문에서는 다른 셀로부터 발생하는 간섭을 고려하여 다중사용자 다중안테나 하향링크 채널에서 최소평균제곱오차(MMSE: minimum mean-squared error)에 기반한 비선형 연속 프리코딩(precoding) 기법을 제안한다. 기존의 zero forcing(ZF) 기반의 방법과 달리 제안하는 방식은 다른 셀로부터의 간섭을 고려하여 셀 내의 다중사용자 간섭을 억제하는 방식을 취하여 수신단에서의 신호 대 간섭 잡음비를 향상시킬 수 있다. 모의 실험 결과를 통해 제안하는 최소평균제곱오차에 기반한 비선형 전처리 기법이 다양한 셀 간섭 환경에서 기존 방법보다 좋은 성능을 가지는 것을 확인할 수 있다.