Power-efficient wireless OFDMA using limited-rate feedback

Marqués, Antonio G.; Giannakis, Georgios B.; Digham, F.F.; Ramos, Francisco

doi:10.1109/twc.2008.060629

Cited by 31 publications

(58 citation statements)

References 19 publications

(31 reference statements)

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“…Additionally, opportunistic scheduling techniques can be combined with OFDM [276]. The problem of using feedback with OFDMA i) scheduling and/or ii) adaptive coding and modulation is also discussed in [10], [132], [175], [176], [206], [208], [309]. The effect of channel variation over time is considered for OFDMA scheduling using feedback in [131].…”

Section: A Single Antenna Scheduling and Spectrum Sharingmentioning

confidence: 99%

An overview of limited feedback in wireless communication systems

Love

Heath

Lau

et al. 2008

IEEE J. Select. Areas Commun.

1,328

918

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Abstract-It is now well known that employing channel adaptive signaling in wireless communication systems can yield large improvements in almost any performance metric. Unfortunately, many kinds of channel adaptive techniques have been deemed impractical in the past because of the problem of obtaining channel knowledge at the transmitter. The transmitter in many systems (such as those using frequency division duplexing) can not leverage techniques such as training to obtain channel state information. Over the last few years, research has repeatedly shown that allowing the receiver to send a small number of information bits about the channel conditions to the transmitter can allow near optimal channel adaptation. These practical systems, which are commonly referred to as limited or finite-rate feedback systems, supply benefits nearly identical to unrealizable perfect transmitter channel knowledge systems when they are judiciously designed. In this tutorial, we provide a broad look at the field of limited feedback wireless communications. We review work in systems using various combinations of single antenna, multiple antenna, narrowband, broadband, single-user, and multiuser technology. We also provide a synopsis of the role of limited feedback in the standardization of next generation wireless systems.

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Section: A Single Antenna Scheduling and Spectrum Sharingmentioning

confidence: 99%

An overview of limited feedback in wireless communication systems

Love

Heath

Lau

et al. 2008

IEEE J. Select. Areas Commun.

1,328

918

View full text Add to dashboard Cite

show abstract

“…Owing to the resource allocation problem in (8)-(8e) being difficult to solve, we will maximise the lower bound of the average throughput in (8) [20]. Therefore, at the stage of resource allocation, if h k m belongs to q k m, j , q k m, j+1 , we will replace h k m with q k m, j and the BER expression can be rewritten by the following equation…”

Section: Resource Allocation Scheme With Proportional Fairness Based mentioning

confidence: 99%

“…Assume the hybrid channel PDF for three mobile users are same and put (19) into (20). Hence we could obtain the following equation…”

Section: Subcarrier Allocation Criterionmentioning

confidence: 99%

Proportional fairness resource allocation scheme based on quantised feedback for multiuser orthogonal frequency division multiplexing system

Yang

et al. 2014

IET Communications

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This work addresses the resource allocation problem with the proportional fair constraint condition based on quantised feedback for multiuser orthogonal frequency division multiplexing access system. The resource allocation problem is converted as an optimisation problem with maximising the lower bound of the total average throughput and this formulation provides the low complexity of solving the above resource allocation problem. Tailored for the above optimisation problem, the authors design the codebook of equivalent channel quantisation threshold and the codebook of power and rate according to the equal probability quantiser and the Lagrange multiplier method, respectively. Further, they develop a suboptimal algorithm based on the stochastic approximate method. The proposed algorithm not only satisfies the constraint condition of the proportional fair very well, but also reduces the feedback overhead of the resource allocation result greatly. Moreover, the average throughput of the proposed algorithm is very close to that of the optimal resource allocation algorithm with full feedback when the equivalent channel gain in every subcarrier is quantised by 4 bit.

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“…In [31], the distribution was derived in a single-antenna system with known co-channel statistics, but the latter assumption is unreasonable in most multi-user scenarios. Observe that the post-user-selection cdf can be written as , for some transformation function .…”

Section: ) Post-user-selection Quantizationmentioning

confidence: 99%

“…If the sample space, , of is quantized into disjoint intervals ( ), where the th interval is with and , then the entropy-maximizing post-userselection quantization is given by (31) Proof: The theorem follows directly from Lemma 1. To illustrate the usefulness of the notation with a transformation function , we consider the following scheduler for which can be derived in closed form.…”

Section: Theorem 4 (Entropy-maximizing Post-user-selection Quantizatimentioning

confidence: 99%

Exploiting Quantized Channel Norm Feedback Through Conditional Statistics in Arbitrarily Correlated MIMO Systems

Björnson

Hammarwall

Ottersten

2009

IEEE Trans. Signal Process.

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Abstract-In the design of narrowband multi-antenna systems, a limiting factor is the amount of channel state information (CSI) available at the transmitter. This is especially evident in multi-user systems, where the spatial user separability determines the multiplexing gain, but it is also important for transmission-rate adaptation in single-user systems. To limit the feedback load, the unknown and multi-dimensional channel needs to be represented by a limited number of bits. When combined with long-term channel statistics, the norm of the channel matrix has been shown to provide substantial CSI that permits efficient user selection, linear precoder design, and rate adaptation. Herein, we consider quantized feedback of the squared Frobenius norm in a Rayleigh fading environment with arbitrary spatial correlation. The conditional channel statistics are characterized and their moments are derived for both identical, distinct, and sets of repeated eigenvalues. These results are applied for minimum mean square error (MMSE) estimation of signal and interference powers in single-and multi-user systems, for the purpose of reliable rate adaptation and resource allocation. The problem of efficient feedback quantization is discussed and an entropy-maximizing framework is developed where the post-user-selection distribution can be taken into account in the design of the quantization levels. The analytic results of this paper are directly applicable in many widely used communication techniques, such as space-time block codes, linear precoding, space division multiple access (SDMA), and scheduling.

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Power-efficient wireless OFDMA using limited-rate feedback

Cited by 31 publications

References 19 publications

An overview of limited feedback in wireless communication systems

An overview of limited feedback in wireless communication systems

Proportional fairness resource allocation scheme based on quantised feedback for multiuser orthogonal frequency division multiplexing system

Exploiting Quantized Channel Norm Feedback Through Conditional Statistics in Arbitrarily Correlated MIMO Systems

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