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Andrea Goldsmith - One of the best experts on this subject based on the ideXlab platform.

  • power and bandwidth allocation in cooperative Dirty Paper Coding
    International Conference on Communications, 2008
    Co-Authors: Nihar Jindal, Andrea Goldsmith, Urbashi Mitra
    Abstract:

    The cooperative Dirty Paper Coding (DPC) rate region is investigated in a two-transmitter two-receiver network with full channel state information available at all terminals. The transmitters cooperate by first exchanging messages over an orthogonal cooperation channel, then they mimic a broadcast channel (BC) and jointly perform DPC to send to the two independent receivers. The allocation of network power and bandwidth between the data and the cooperation channel is studied to characterize the cooperative DPC rate region. First, the optimal sum power allocation for a multiple access channel (MAC) is presented. Then through an application of the MAC-BC capacity duality, the cooperative DPC rate region is evaluated under different bandwidth allocation assumptions. Cooperative DPC outperforms non-cooperative time-division (TD) only when the cooperation channel is strong, since the joint-enCoding capacity gain is negated by the overhead of message exchanges in a weak cooperation channel. Moreover, the cooperative capacity advantage over TD is more pronounced at the maximum sum rate point than when the rate vector is skewed toward one of the users.

  • ICC - Power and Bandwidth Allocation in Cooperative Dirty Paper Coding
    2008 IEEE International Conference on Communications, 2008
    Co-Authors: Nihar Jindal, Andrea Goldsmith, Urbashi Mitra
    Abstract:

    The cooperative Dirty Paper Coding (DPC) rate region is investigated in a two-transmitter two-receiver network with full channel state information available at all terminals. The transmitters cooperate by first exchanging messages over an orthogonal cooperation channel, then they mimic a broadcast channel (BC) and jointly perform DPC to send to the two independent receivers. The allocation of network power and bandwidth between the data and the cooperation channel is studied to characterize the cooperative DPC rate region. First, the optimal sum power allocation for a multiple access channel (MAC) is presented. Then through an application of the MAC-BC capacity duality, the cooperative DPC rate region is evaluated under different bandwidth allocation assumptions. Cooperative DPC outperforms non-cooperative time-division (TD) only when the cooperation channel is strong, since the joint-enCoding capacity gain is negated by the overhead of message exchanges in a weak cooperation channel. Moreover, the cooperative capacity advantage over TD is more pronounced at the maximum sum rate point than when the rate vector is skewed toward one of the users.

  • Dirty-Paper Coding versus TDMA for MIMO Broadcast channels
    IEEE Transactions on Information Theory, 2005
    Co-Authors: Nihar Jindal, Andrea Goldsmith
    Abstract:

    We compare the capacity of Dirty-Paper Coding (DPC) to that of time-division multiple access (TDMA) for a multiple-antenna (multiple-input multiple-output (MIMO)) Gaussian broadcast channel (BC). We find that the sum-rate capacity (achievable using DPC) of the multiple-antenna BC is at most min(M,K) times the largest single-user capacity (i.e., the TDMA sum-rate) in the system, where M is the number of transmit antennas and K is the number of receivers. This result is independent of the number of receive antennas and the channel gain matrix, and is valid at all signal-to-noise ratios (SNRs). We investigate the tightness of this bound in a time-varying channel (assuming perfect channel knowledge at receivers and transmitters) where the channel experiences uncorrelated Rayleigh fading and in some situations we find that the Dirty Paper gain is upper-bounded by the ratio of transmit-to-receive antennas. We also show that min(M,K) upper-bounds the sum-rate gain of successive deCoding over TDMA for the uplink channel, where M is the number of receive antennas at the base station and K is the number of transmitters.

  • transmitter cooperation in ad hoc wireless networks does Dirty Paper Coding beat relaying
    Information Theory Workshop, 2004
    Co-Authors: Andrea Goldsmith
    Abstract:

    We investigate capacity and achievable rates for transmitter cooperation schemes in ad-hoc wireless networks. In addition to cooperative Dirty Paper Coding, we propose two new cooperative transmission techniques: time-division successive broadcasting and time-division relaying. We show that transmitter cooperation can significantly increase capacity, even if one of the cooperating nodes is halfway between the transmit and receive node clusters. However, the best form of cooperation depends on the relative geometry of the transmit and receive clusters. When the transmitters are close together, cooperative Dirty Paper Coding achieves the highest rates. However, if one of the transmitters is relatively close to the receive cluster, cooperative broadcasting or relaying achieves higher rates than Dirty Paper Coding. That is because, at large separations, the exchange of messages between the transmitters required for Dirty Paper Coding consumes a substantial amount of power. We show that in most cases transmitter cooperation provides a substantial capacity improvement over noncooperative techniques, especially under an equal rate constraint.

  • capacity and Dirty Paper Coding for gaussian broadcast channels with common information
    International Symposium on Information Theory, 2004
    Co-Authors: Nihar Jindal, Andrea Goldsmith
    Abstract:

    We consider a set of parallel, two-user scalar Gaussian broadcast channels, where the transmitter wishes to send independent information to each of the receivers and common information to both receivers. The capacity region of this channel is implicitly characterized in [A. El Gamal, (1980)]. Here, we provide an explicit characterization of the power and rate allocation schemes that achieve the boundary of the three-dimensional rate region. We also propose a Dirty-Paper Coding achievable region for MIMO broadcast channels with common information.

Mehmet Kemal Karakayali - One of the best experts on this subject based on the ideXlab platform.

  • Practical Dirty Paper Coding With Sum Codes
    IEEE Transactions on Communications, 2016
    Co-Authors: Kiran M Rege, Krishna Balachandran, Joseph H Kang, Mehmet Kemal Karakayali
    Abstract:

    In this Paper, we present a practical method to construct Dirty Paper Coding (DPC) schemes using sum codes. Unlike the commonly used approach to DPC where the Coding scheme involves concatenation of a channel code and a quantization code, the proposed method embodies a unified approach that emulates the binning method used in the proof of the DPC result. Auxiliary bits are used to create the desired number of code vectors in each bin. Sum codes are obtained when information sequences augmented with auxiliary bits are encoded using linear block codes. Sum-code-based DPC schemes can be implemented using any linear block code, and entail a relatively small increase in decoder complexity when compared to standard communication schemes. They can also lead to significant reduction in transmit power in comparison to standard schemes.

  • a practical Dirty Paper Coding scheme based on ldpc codes
    Wireless Communications and Networking Conference, 2014
    Co-Authors: Kiran M Rege, Krishna Balachandran, Joseph H Kang, Mehmet Kemal Karakayali
    Abstract:

    In this Paper, we present a practical Dirty Paper Coding (DPC) scheme using sum codes based on LDPC codes. While a typical sum-code-based DPC scheme uses a constrained decoder as part of the enCoding operation, such an approach fails in the case of LDPC codes since the constrained decoder based on a standard LDPC decoder tends to get stuck at highly suboptimal points in typical scenarios. We get around this difficulty via a simple code construction method based on bit- mapping or permutation. Examples included in this Paper show that compared to standard communication schemes the proposed DPC scheme yields substantial savings in terms of the

  • WCNC - A Practical Dirty Paper Coding Scheme Based on LDPC Codes
    2014 IEEE Wireless Communications and Networking Conference (WCNC), 2014
    Co-Authors: Kiran M Rege, Krishna Balachandran, Joseph H Kang, Mehmet Kemal Karakayali
    Abstract:

    In this Paper, we present a practical Dirty Paper Coding (DPC) scheme using sum codes based on LDPC codes. While a typical sum-code-based DPC scheme uses a constrained decoder as part of the enCoding operation, such an approach fails in the case of LDPC codes since the constrained decoder based on a standard LDPC decoder tends to get stuck at highly suboptimal points in typical scenarios. We get around this difficulty via a simple code construction method based on bit- mapping or permutation. Examples included in this Paper show that compared to standard communication schemes the proposed DPC scheme yields substantial savings in terms of the

  • Dirty Paper Coding using trellis coded modulation
    Personal Indoor and Mobile Radio Communications, 2013
    Co-Authors: Kiran M Rege, Krishna Balachandran, Joseph H Kang, Mehmet Kemal Karakayali
    Abstract:

    Although the information theoretic result referred to as “Dirty Paper Coding” [1] has been known for quite a while, it has not led to schemes that look attractive enough for real-life communication systems. In a companion Paper [2], we presented the concept of sum codes and showed how they provide a convenient platform for interference suppression via Dirty Paper Coding. In this Paper, we present a Dirty Paper Coding scheme based on trellis-coded modulation, which could be looked upon as an alternative to the sum-codes-based approach. Since trellis-coded modulation is designed for multi-level signal constellations, it is expected to work well as a platform for the proposed Dirty Paper Coding scheme in which multi-level signal constellations play a critical role.

  • Dirty Paper Coding using sum codes
    Personal Indoor and Mobile Radio Communications, 2013
    Co-Authors: Kiran M Rege, Krishna Balachandran, Joseph H Kang, Mehmet Kemal Karakayali
    Abstract:

    While the information theoretic result commonly referred to as “Dirty Paper Coding” [1] has been known for long, it has not led to practical schemes that can be implemented easily in real-life communication systems. In this Paper, we present the concept of sum codes and show how they provide a convenient platform for Dirty Paper Coding. Comb-combined sum codes, which provide a convenient method of sum-code construction, are particularly useful in this respect. One can build comb-combined sum codes based on any linear block code to achieve reduction in the transmit energy required to attain a desired performance. Using an example based on tail-biting convolutional codes, we show how practical Dirty Paper Coding may be implemented using any convenient linear block code.

Nihar Jindal - One of the best experts on this subject based on the ideXlab platform.

  • power and bandwidth allocation in cooperative Dirty Paper Coding
    International Conference on Communications, 2008
    Co-Authors: Nihar Jindal, Andrea Goldsmith, Urbashi Mitra
    Abstract:

    The cooperative Dirty Paper Coding (DPC) rate region is investigated in a two-transmitter two-receiver network with full channel state information available at all terminals. The transmitters cooperate by first exchanging messages over an orthogonal cooperation channel, then they mimic a broadcast channel (BC) and jointly perform DPC to send to the two independent receivers. The allocation of network power and bandwidth between the data and the cooperation channel is studied to characterize the cooperative DPC rate region. First, the optimal sum power allocation for a multiple access channel (MAC) is presented. Then through an application of the MAC-BC capacity duality, the cooperative DPC rate region is evaluated under different bandwidth allocation assumptions. Cooperative DPC outperforms non-cooperative time-division (TD) only when the cooperation channel is strong, since the joint-enCoding capacity gain is negated by the overhead of message exchanges in a weak cooperation channel. Moreover, the cooperative capacity advantage over TD is more pronounced at the maximum sum rate point than when the rate vector is skewed toward one of the users.

  • ICC - Power and Bandwidth Allocation in Cooperative Dirty Paper Coding
    2008 IEEE International Conference on Communications, 2008
    Co-Authors: Nihar Jindal, Andrea Goldsmith, Urbashi Mitra
    Abstract:

    The cooperative Dirty Paper Coding (DPC) rate region is investigated in a two-transmitter two-receiver network with full channel state information available at all terminals. The transmitters cooperate by first exchanging messages over an orthogonal cooperation channel, then they mimic a broadcast channel (BC) and jointly perform DPC to send to the two independent receivers. The allocation of network power and bandwidth between the data and the cooperation channel is studied to characterize the cooperative DPC rate region. First, the optimal sum power allocation for a multiple access channel (MAC) is presented. Then through an application of the MAC-BC capacity duality, the cooperative DPC rate region is evaluated under different bandwidth allocation assumptions. Cooperative DPC outperforms non-cooperative time-division (TD) only when the cooperation channel is strong, since the joint-enCoding capacity gain is negated by the overhead of message exchanges in a weak cooperation channel. Moreover, the cooperative capacity advantage over TD is more pronounced at the maximum sum rate point than when the rate vector is skewed toward one of the users.

  • high snr analysis for mimo broadcast channels Dirty Paper Coding versus linear preCoding
    IEEE Transactions on Information Theory, 2007
    Co-Authors: Juyul Lee, Nihar Jindal
    Abstract:

    In this correspondence, we compare the achievable throughput for the optimal strategy of Dirty Paper Coding (DPC) to that achieved with suboptimal and lower complexity linear preCoding techniques (zero-forcing and block diagonalization). Both strategies utilize all available spatial dimensions and therefore have the same multiplexing gain, but an absolute difference in terms of throughput does exist. The sum rate difference between the two strategies is analytically computed at asymptotically high SNR. Furthermore, the difference is not affected by asymmetric channel behavior when each user has a different average SNR. Weighted sum rate maximization is also considered. In the process, it is shown that allocating user powers in direct proportion to user weights asymptotically maximizes weighted sum rate.

  • Dirty Paper Coding vs. Linear PreCoding for MIMO Broadcast Channels
    2006 Fortieth Asilomar Conference on Signals Systems and Computers, 2006
    Co-Authors: Juyul Lee, Nihar Jindal
    Abstract:

    We study the MIMO broadcast channel and compare the achievable throughput for the optimal strategy of Dirty Paper Coding to that achieved with sub-optimal and lower complexity linear preCoding (e.g., zero-forcing and block diagonalization) transmission. Both strategies utilize all available spatial dimensions and therefore have the same multiplexing gain, but an absolute difference in terms of throughput does exist. The sum rate difference between the two strategies is analytically computed at asymptotically high SNR, and it is seen that this asymptotic statistic provides an accurate characterization at even moderate SNR levels. Weighted sum rate maximization is also considered, and a similar quantification of the throughput difference between the two strategies is computed. In the process, it is shown that allocating user powers in direct proportion to user weights asymptotically maximizes weighted sum rate.

  • Dirty-Paper Coding versus TDMA for MIMO Broadcast channels
    IEEE Transactions on Information Theory, 2005
    Co-Authors: Nihar Jindal, Andrea Goldsmith
    Abstract:

    We compare the capacity of Dirty-Paper Coding (DPC) to that of time-division multiple access (TDMA) for a multiple-antenna (multiple-input multiple-output (MIMO)) Gaussian broadcast channel (BC). We find that the sum-rate capacity (achievable using DPC) of the multiple-antenna BC is at most min(M,K) times the largest single-user capacity (i.e., the TDMA sum-rate) in the system, where M is the number of transmit antennas and K is the number of receivers. This result is independent of the number of receive antennas and the channel gain matrix, and is valid at all signal-to-noise ratios (SNRs). We investigate the tightness of this bound in a time-varying channel (assuming perfect channel knowledge at receivers and transmitters) where the channel experiences uncorrelated Rayleigh fading and in some situations we find that the Dirty Paper gain is upper-bounded by the ratio of transmit-to-receive antennas. We also show that min(M,K) upper-bounds the sum-rate gain of successive deCoding over TDMA for the uplink channel, where M is the number of receive antennas at the base station and K is the number of transmitters.

Kiran M Rege - One of the best experts on this subject based on the ideXlab platform.

  • Interference mitigation in heterogeneous networks with simple Dirty Paper Coding
    Wireless Networks, 2020
    Co-Authors: Kiran M Rege, Krishna Balachandran, Joseph H Kang, Kemal Karakayali
    Abstract:

    In heterogeneous networks where macro cells and metro cells use the same frequency band to communicate with their respective users, the major problem limiting performance is the interference caused by macro cells to metro cells. The information theoretic result known as Dirty Paper Coding provides a way to address this problem and significantly improve the performance of heterogeneous networks with co-channel deployment. In this Paper, we show how a simple Dirty Paper Coding scheme employing Tomlinson-Harashima pre-Coding with partial interference pre-subtraction can be employed by metro cells to mitigate the interference caused by macro cells. A performance study included in this Paper shows that the proposed Dirty Paper Coding scheme can lead to significant improvement in user rate statistics.

  • Practical Dirty Paper Coding With Sum Codes
    IEEE Transactions on Communications, 2016
    Co-Authors: Kiran M Rege, Krishna Balachandran, Joseph H Kang, Mehmet Kemal Karakayali
    Abstract:

    In this Paper, we present a practical method to construct Dirty Paper Coding (DPC) schemes using sum codes. Unlike the commonly used approach to DPC where the Coding scheme involves concatenation of a channel code and a quantization code, the proposed method embodies a unified approach that emulates the binning method used in the proof of the DPC result. Auxiliary bits are used to create the desired number of code vectors in each bin. Sum codes are obtained when information sequences augmented with auxiliary bits are encoded using linear block codes. Sum-code-based DPC schemes can be implemented using any linear block code, and entail a relatively small increase in decoder complexity when compared to standard communication schemes. They can also lead to significant reduction in transmit power in comparison to standard schemes.

  • a practical Dirty Paper Coding scheme based on ldpc codes
    Wireless Communications and Networking Conference, 2014
    Co-Authors: Kiran M Rege, Krishna Balachandran, Joseph H Kang, Mehmet Kemal Karakayali
    Abstract:

    In this Paper, we present a practical Dirty Paper Coding (DPC) scheme using sum codes based on LDPC codes. While a typical sum-code-based DPC scheme uses a constrained decoder as part of the enCoding operation, such an approach fails in the case of LDPC codes since the constrained decoder based on a standard LDPC decoder tends to get stuck at highly suboptimal points in typical scenarios. We get around this difficulty via a simple code construction method based on bit- mapping or permutation. Examples included in this Paper show that compared to standard communication schemes the proposed DPC scheme yields substantial savings in terms of the

  • WCNC - A Practical Dirty Paper Coding Scheme Based on LDPC Codes
    2014 IEEE Wireless Communications and Networking Conference (WCNC), 2014
    Co-Authors: Kiran M Rege, Krishna Balachandran, Joseph H Kang, Mehmet Kemal Karakayali
    Abstract:

    In this Paper, we present a practical Dirty Paper Coding (DPC) scheme using sum codes based on LDPC codes. While a typical sum-code-based DPC scheme uses a constrained decoder as part of the enCoding operation, such an approach fails in the case of LDPC codes since the constrained decoder based on a standard LDPC decoder tends to get stuck at highly suboptimal points in typical scenarios. We get around this difficulty via a simple code construction method based on bit- mapping or permutation. Examples included in this Paper show that compared to standard communication schemes the proposed DPC scheme yields substantial savings in terms of the

  • Dirty Paper Coding using trellis coded modulation
    Personal Indoor and Mobile Radio Communications, 2013
    Co-Authors: Kiran M Rege, Krishna Balachandran, Joseph H Kang, Mehmet Kemal Karakayali
    Abstract:

    Although the information theoretic result referred to as “Dirty Paper Coding” [1] has been known for quite a while, it has not led to schemes that look attractive enough for real-life communication systems. In a companion Paper [2], we presented the concept of sum codes and showed how they provide a convenient platform for interference suppression via Dirty Paper Coding. In this Paper, we present a Dirty Paper Coding scheme based on trellis-coded modulation, which could be looked upon as an alternative to the sum-codes-based approach. Since trellis-coded modulation is designed for multi-level signal constellations, it is expected to work well as a platform for the proposed Dirty Paper Coding scheme in which multi-level signal constellations play a critical role.

Zixiang Xiong - One of the best experts on this subject based on the ideXlab platform.

  • joint slepian wolf Dirty Paper Coding
    International Conference on Communications, 2013
    Co-Authors: Momin Uppal, Khalid A Qaraqe, Zixiang Xiong
    Abstract:

    We consider a joint Slepian-Wolf/Dirty-Paper Coding (SW-DPC) setup where a binary source needs to be transmitted over an additive white-Gaussian channel in the presence of interference known only at the encoder, as well as correlated side-information available only at the decoder. We propose a practical joint SW-DPC framework that uses a single low-density parity-check code coupled with trellis coded quantization to simultaneously provide error protection (in the face of noise and interference) and compression (in the face of correlated side-information available at the decoder). Simulation results indicate that the proposed joint SW-DPC scheme with finite-length codes outperforms a scheme with separate SW and DPC by 0.3 dB. In addition, we show that our joint SW-DPC code designed for one set of channel conditions is capable of achieving negligible bit-error rates for many other channel conditions as well. More specifically, it achieves successful deCoding for a wide variety of channel conditions for which a separation-based scheme fails.

  • ICC - Joint Slepian-Wolf/Dirty-Paper Coding
    2013 IEEE International Conference on Communications (ICC), 2013
    Co-Authors: Momin Uppal, Khalid A Qaraqe, Zixiang Xiong
    Abstract:

    We consider a joint Slepian-Wolf/Dirty-Paper Coding (SW-DPC) setup where a binary source needs to be transmitted over an additive white-Gaussian channel in the presence of interference known only at the encoder, as well as correlated side-information available only at the decoder. We propose a practical joint SW-DPC framework that uses a single low-density parity-check code coupled with trellis coded quantization to simultaneously provide error protection (in the face of noise and interference) and compression (in the face of correlated side-information available at the decoder). Simulation results indicate that the proposed joint SW-DPC scheme with finite-length codes outperforms a scheme with separate SW and DPC by 0.3 dB. In addition, we show that our joint SW-DPC code designed for one set of channel conditions is capable of achieving negligible bit-error rates for many other channel conditions as well. More specifically, it achieves successful deCoding for a wide variety of channel conditions for which a separation-based scheme fails.

  • A Robust Multi-Level Design for Dirty-Paper Coding
    IEEE Transactions on Communications, 2013
    Co-Authors: Momin Uppal, Guosen Yue, Yan Xin, Xiaodong Wang, Zixiang Xiong
    Abstract:

    We propose a robust close-to-capacity Dirty-Paper Coding (DPC) design framework in which multi-level low density parity check (LDPC) codes and trellis coded quantization (TCQ) are employed as the channel and source Coding components, respectively. The proposed design framework is robust in the sense that it yields close to capacity solutions in the high-, medium-, and low-rate regimes. This is in contrast to existing practical DPC schemes that perform well only in one or two of these regimes, but not all three. We design codes for transmission rates of 0.5, 1.0, 1.5, and 2.0 bits/sample (b/s) using one, two, three, and four LDPC levels; at a block length of 2×105, the codes perform 0.95, 0.58, 0.55, and 0.54 dB from the corresponding information theoretic limits, respectively. We also propose a low-complexity deCoding scheme that does not involve iterative message passing between the source and channel decoders; the low-complexity scheme performs only 1.08, 0.85, and 0.79 dB away from the theoretical limits at transmission rates of 1.0, 1.5, and 2.0 b/s, respectively.

  • a multi level design for Dirty Paper Coding with applications to the cognitive radio channel
    Global Communications Conference, 2011
    Co-Authors: Momin Uppal, Guosen Yue, Yan Xin, Xiaodong Wang, Zixiang Xiong
    Abstract:

    We propose a close-to-capacity Dirty-Paper Coding framework which employs multi-level low density parity-check (LDPC) and trellis coded quantization. The proposed Coding framework is robust in the sense that it performs close to capacity in the high as well as the low rate regimes. This is in contrast to existing practical DPC schemes which perform well at one of these regimes, but never both. In order to evaluate the performance of our scheme, we consider its application to a cognitive radio channel. At a block length of $2\times 10^5$, the designed Dirty-Paper Coding scheme operates within 0.95, 0.58 and 0.6 dB of the theoretical limit at transmission rates of 0.5, 1.0 and 1.5 bits/sample, respectively. As far as the authors are aware, this is the best performance reported in the literature so far.

  • GLOBECOM - A Multi-Level Design for Dirty-Paper Coding with Applications to the Cognitive Radio Channel
    2011 IEEE Global Telecommunications Conference - GLOBECOM 2011, 2011
    Co-Authors: Momin Uppal, Guosen Yue, Yan Xin, Xiaodong Wang, Zixiang Xiong
    Abstract:

    We propose a close-to-capacity Dirty-Paper Coding framework which employs multi-level low density parity-check (LDPC) and trellis coded quantization. The proposed Coding framework is robust in the sense that it performs close to capacity in the high as well as the low rate regimes. This is in contrast to existing practical DPC schemes which perform well at one of these regimes, but never both. In order to evaluate the performance of our scheme, we consider its application to a cognitive radio channel. At a block length of $2\times 10^5$, the designed Dirty-Paper Coding scheme operates within 0.95, 0.58 and 0.6 dB of the theoretical limit at transmission rates of 0.5, 1.0 and 1.5 bits/sample, respectively. As far as the authors are aware, this is the best performance reported in the literature so far.