Adaptive MIMO-OFDM combining space-time block codes and spatial multiplexing

Halmi, Mohd Hairi; Chieng, D.H.T.

doi:10.1109/isssta.2004.1371739

Cited by 8 publications

(6 citation statements)

References 8 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The proposed hybrid STBC/SM schemes are compared with other conventional systems such as the open-loop scheme in [2] and the closed-loop AA scheme in [5] which takes two feedback bits from the receiver to assign four streams at the transmitter. Also, the performance of open-loop ML detection schemes is plotted for comparison.…”

Section: Simulation Resultsmentioning

confidence: 99%

“…We can see that the curves of the proposed scheme approach that of the optimum case (TYPE 4) as the number of feedback phase values increases from TYPE 1 to TYPE 4. The plots show that TYPE 4 guarantees almost 2.5 dB higher received SNR than the closed-loop antenna assignment (AA) scheme presented in [5]. Also, TYPE 1a achieves an additional gain over TYPE 1 by selecting the best precoding matrix.…”

Section: Practical Precoding With Reduced Feedback Informationmentioning

confidence: 97%

“…In [5], a simple hybrid STBC/SM scheme with CSI known at the transmitter was introduced. In this paper, we propose a new hybrid STBC/SM scheme for a closed-loop MIMO system, which allows a simple maximum-likelihood (ML) receiver with small feedback amount.…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

A New Hybrid Space-Time Block Codes and Spatial Multiplexing Scheme with Precoding

Kim

Lee²,

Lee³

2007

2007 IEEE International Conference on Communications

View full text Add to dashboard Cite

We present a new hybrid scheme which combines space-time block codes (STBC) and spatial multiplexing (SM) to achieve both diversity and spatial multiplexing gain. We design a new precoding scheme based on the Givens rotation by utilizing the phase feedback information from the receiver. Exploiting the STBC structure embedded in the hybrid scheme, the proposed scheme enables a simple maximum likelihood (ML) detection such that the receiver complexity is reduced by a factor of 1/16 for the case of 4bps/Hz. Practical precoder designs are also provided to minimize the feedback information, while maintaining near optimal performance. Also, unlike conventional schemes which require at least two receive antennas, the proposed hybrid scheme works well with a single receive antenna. Simulation results show that the proposed hybrid scheme achieves a performance gain of 7dB at a bit error rate (BER) of 10 −4 in 2 bps/Hz spectral efficiency over other closedloop hybrid schemes.

show abstract

Section: Simulation Resultsmentioning

confidence: 99%

Section: Practical Precoding With Reduced Feedback Informationmentioning

confidence: 97%

See 1 more Smart Citation

A New Hybrid Space-Time Block Codes and Spatial Multiplexing Scheme with Precoding

Kim

Lee²,

Lee³

2007

2007 IEEE International Conference on Communications

View full text Add to dashboard Cite

show abstract

“…In [11], modulation, error correction coding and MIMO encoding are coarsely adapted according to CSI estimators to maximize the effective throughput. More recently, fine grain adaptation schemes, tuning carrierper-carrier the modulation and MIMO encoding, have been proposed [12,13]. The main challenge with such schemes is to provide the required CSI to the transmitter with minimal overhead [14].…”

Section: Department Of Electrical Engineeringmentioning

confidence: 99%

SmartMIMO: Energy-Aware Adaptive MIMO-OFDM Radio Link Control for Wireless Local Area Networks

Bougard

Lenoir

Dejonghe

et al. 2006

2006 IEEE Workshop on Signal Processing Systems Design and Implementation

View full text Add to dashboard Cite

Multiple-antenna techniques (MIMO) have beenproposed to improve wireless links spectrum efficiency and/or robustness. There exists a fundamental tradeoff between potential spectrum efficiency and robustness increase.But these multiple-antenna techniques come with an overhead in power consumption due to the duplication of part of the transmitter and receiver front-ends. From a system perspective, one has to focus on performance versus power consumption tradeoff. In this paper, we derive SmartMIMO: an adaptive energy-aware link adaptation approach which, next to the modulation and code rate, decides on using either space-division multiplexing (increasing spectrum efficiency) or space-time coding (increasing robustness) to transmit a given packet on a given MIMO channel. Energy-efficiency is shown to be improved by up to 30% when compared to nonadaptive techniques while the average rate is improved by up to 50% when compared to single-antenna transmission.I INTRODUCTION The performance of wireless communication systems can drastically be improved when using multiple-antenna transmission techniques. Such techniques can be used to increase antenna gain and directionality (beamforming, [1]), to improve link robustness (space-time coding [2,3]) or to improve spectrum efficiency (space division multiplexing [4]). Techniques where multiple antennas are considered both at transmit and receive sides can combine those assets and are referred to as MIMO (Multiple-input, Multiple-output). On the other hand, because of its robustness in harsh frequency-selective channel combined with a low implementation cost, orthogonal frequency division multiplexing (OFDM) is currently pervasive in broadband wireless communication. Therefore, MIMO-OFDM schemes turn out to be excellent candidates for next generation broadband wireless standards [5]). Traditionally, the benefit of MIMO schemes is characterized in terms of multiplexing gain (i.e., the increase in spectrum efficiency) and diversity gain (namely, the increase in immunity to the channel variation, quantified as the order of the decay of the bit error rate as a function of the signal-to-noise ratio). In [6], it is shown that, given a MIMO channel and assuming a high signal-to-noise ratio, there exists a fundamental tradeoff between how much of these gains a given coding scheme can extract. Since then, the merits of MIMO schemes are evaluated with regard to that tradeoff. However, from the link perspective, the tradeoff that has to be assessed is between average user data rate and energy efficiency. Characterizing how a diversity gain, a multiplexing gain and/or a coding gain influence the user-relevant tradeoff is not trivial. Transceiver' power consumption is generally made of two terms. The first corresponds to the power amplifier(s) consumption and is function of the transmit power, inferred from the link budget. The second corresponds to the electronics power consumption and is independent of the link budget. We refer respectively to dynamic and static power consumption. The im...

show abstract

“…Second, we propose smartMIMO, a coarsely adaptive MIMO-OFDM scheme that, on a packet-per-packet basis, switches between STBC, SDM, and SISO depending on the channel conditions to simultaneously secure the throughput and/or robustness improvement provided by the multiantenna transmission and guarantees an energy-efficiency improved compared with the current standards. Contrarily in other adaptive scheme [12][13][14][15][16], using SISO still reveal effective in many channel condition because of the saving in static power consumption.…”

Section: Introductionmentioning

confidence: 99%

SmartMIMO: An Energy-Aware Adaptive MIMO-OFDM Radio Link Control for Next-Generation Wireless Local Area Networks

Bougard

Lenoir

Dejonghe

et al. 2007

J Wireless Com Network

View full text Add to dashboard Cite

Multiantenna systems and more particularly those operating on multiple input and multiple output (MIMO) channels are currently a must to improve wireless links spectrum efficiency and/or robustness. There exists a fundamental tradeoff between potential spectrum efficiency and robustness increase. However, multiantenna techniques also come with an overhead in silicon implementation area and power consumption due, at least, to the duplication of part of the transmitter and receiver radio frontends. Although the area overhead may be acceptable in view of the performance improvement, low power consumption must be preserved for integration in nomadic devices. In this case, it is the tradeoff between performance (e.g., the net throughput on top of the medium access control layer) and average power consumption that really matters. It has been shown that adaptive schemes were mandatory to avoid that multiantenna techniques hamper this system tradeoff. In this paper, we derive smartMIMO: an adaptive multiantenna approach which, next to simply adapting the modulation and code rate as traditionally considered, decides packet-per-packet, depending on the MIMO channel state, to use either space-division multiplexing (increasing spectrum efficiency), space-time coding (increasing robustness), or to stick to single-antenna transmission. Contrarily to many of such adaptive schemes, the focus is set on using multiantenna transmission to improve the link energy efficiency in real operation conditions. Based on a model calibrated on an existing reconfigurable multiantenna transceiver setup, the link energy efficiency with the proposed scheme is shown to be improved by up to 30% when compared to nonadaptive schemes. The average throughput is, on the other hand, improved by up to 50% when compared to single-antenna transmission.

show abstract

Adaptive MIMO-OFDM combining space-time block codes and spatial multiplexing

Cited by 8 publications

References 8 publications

A New Hybrid Space-Time Block Codes and Spatial Multiplexing Scheme with Precoding

A New Hybrid Space-Time Block Codes and Spatial Multiplexing Scheme with Precoding

SmartMIMO: Energy-Aware Adaptive MIMO-OFDM Radio Link Control for Wireless Local Area Networks

SmartMIMO: An Energy-Aware Adaptive MIMO-OFDM Radio Link Control for Next-Generation Wireless Local Area Networks

Contact Info

Product

Resources

About