25,805 research outputs found
Delay-Optimal Buffer-Aware Probabilistic Scheduling with Adaptive Transmission
Cross-layer scheduling is a promising way to improve Quality of Service (QoS)
given a power constraint. In this paper, we investigate the system with random
data arrival and adaptive transmission. Probabilistic scheduling strategies
aware of the buffer state are applied to generalize conventional deterministic
scheduling. Based on this, the average delay and power consumption are analysed
by Markov reward process. The optimal delay-power tradeoff curve is the Pareto
frontier of the feasible delay-power region. It is proved that the optimal
delay-power tradeoff is piecewise-linear, whose vertices are obtained by
deterministic strategies. Moreover, the corresponding strategies of the optimal
tradeoff curve are threshold-based, hence can be obtained by a proposed
effective algorithm. On the other hand, we formulate a linear programming to
minimize the average delay given a fixed power constraint. By varying the power
constraint, the optimal delay-power tradeoff curve can also be obtained. It is
demonstrated that the algorithm result and the optimization result match each
other, and are further validated by Monte-Carlo simulation.Comment: 6 pages, 4 figures, accepted by IEEE ICCC 201
A new class of parallel data convolutional codes
We propose a new class of parallel data convolutional
codes (PDCCs) in this paper. The PDCC encoders inputs
are composed of an original block of data and its interleaved version.
A novel single self-iterative soft-in/soft-out a posteriori probability
(APP) decoder structure is proposed for the decoding of
the PDCCs. Simulation results are presented to compare the performance
of PDCCs
On the capacity and normalisation of ISI channels
[Abstract]: We investigate the capacity of various ISI channels with additive white Gaussian noise. Previous papers showed
a minimum Eb/N0 of −4.6 dB, 3 dB below the capacity of
a flat channel, is obtained using the water-pouring capacity
formulas for the 1 + D channel. However, these papers did
not take into account that the channel power gain can be
greater than unity when water-pouring is used. We present a
generic power normalization method of the channel frequency
response, namely peak bandwidth normalisation, to facilitate the fair capacity comparison of various ISI channels. Three types of ISI channel, i.e., adder channels, RC channels and magnetic recording channels, are examined. By using our channel power gain normalization, the capacity curves of these ISI channels are shown
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