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A Construction for Binary Sequence Sets with Low PeaktoAverage Power Ratio
"... A recursive construction is provided for sequence sets which possess good Hamming Distance and low PeaktoAverage Power Ratio (PAR) under any Local Unitary Unimodular Transform (including all one and multidimensional Discrete Fourier Transforms). An important instance of the construction identifie ..."
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Cited by 14 (9 self)
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A recursive construction is provided for sequence sets which possess good Hamming Distance and low PeaktoAverage Power Ratio (PAR) under any Local Unitary Unimodular Transform (including all one and multidimensional Discrete Fourier Transforms). An important instance of the construction identifies an iteration and specialisation of the MaioranaMcFarland (MM) construction. I.
New Complete Complementary Codes for PeaktoMean Power Control in MultiCarrier CDMA
"... Owing to the zero nontrivial aperiodic correlation sum properties, complete complementary codes (CCC) have been applied to asynchronous multicarrier codedivision multipleaccess (MCCDMA) communications in order to provide zero interference performance. When each complementary code is arranged to ..."
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Cited by 4 (4 self)
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Owing to the zero nontrivial aperiodic correlation sum properties, complete complementary codes (CCC) have been applied to asynchronous multicarrier codedivision multipleaccess (MCCDMA) communications in order to provide zero interference performance. When each complementary code is arranged to be a matrix, the peaktomean envelope power ratio (PMEPR) of the CCCMCCDMA system is determined by the column sequences of the complementary matrices. The existing CCC have the column sequence PMEPR of M, where M denotes the number of subcarriers in a CCCMCCDMA system. In practice, M is generally large and a PMEPR approaching this value is unacceptable. To solve this problem, a new class of CCC using generalized Boolean functions and with a column sequence PMEPR of at most 2 is proposed in this paper.
SPATIAL PROCESSING, POWER CONTROL, AND CHANNEL ALLOCATION FOR OFDM WIRELESS COMMUNICATIONS
, 2003
"... OFDM is mainly designed to combat the effect of multipath reception, by dividing the wideband frequency selective fading channel into many narrowband flat subchannels. OFDM offers flexibility in adaptation to timevarying channel condition by adopting the parameters at each subcarrier accurately. ..."
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Cited by 1 (0 self)
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OFDM is mainly designed to combat the effect of multipath reception, by dividing the wideband frequency selective fading channel into many narrowband flat subchannels. OFDM offers flexibility in adaptation to timevarying channel condition by adopting the parameters at each subcarrier accurately. The purpose of this work is to use this flexibility and study the OFDM systems with power control, multiple transmit and receive antennas, the problem of Peak to Average Power Ratio (PAPR), and the effect of OFDM in providing QoS. An OFDM uplink multiuser wireless network, combined with power control and receive beamforming is proposed to achieve the desired SINR at each OFDM subchannel. Consequently, better overall BER with the same total power is achieved. To reduce the receivercomplexity, joint timedomain beamforming and power control is also provided. The proposed algorithm is also extended to COFDM. We use distributed schemes to maximize the maximum achievable data rate for each receiver in a multiuser downlink transmission using MIMO/OFDM, by finding the optimal transmit and receive weight vectors. We propose iterative algorithms to distribute the limited power (per carrier or per user) to multiple streams and multiple antennas in order to
HadamardCoded Modulation for Visible Light Communications
"... AbstractVisible light communication (VLC) systems using the indoor lighting system to also provide downlink communications require highaverage optical powers to satisfy the illumination needs. This can cause highamplitude signals common in higherorder modulation schemes to be clipped by the peak ..."
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AbstractVisible light communication (VLC) systems using the indoor lighting system to also provide downlink communications require highaverage optical powers to satisfy the illumination needs. This can cause highamplitude signals common in higherorder modulation schemes to be clipped by the peak power constraint of the light emitting diode (LED) and lead to highsignal distortion. In this paper, we introduce Hadamard coded modulation (HCM) to achieve low error probabilities in LEDbased VLC systems needing highaverage optical powers. This technique uses a fast WalshHadamard transform (FWHT) to modulate the data as an alternative modulation technique to orthogonal frequency division multiplexing (OFDM). HCM achieves a better performance for highillumination levels because of its small peak to average power ratio
CCSFOSSIL and DualChannel System That Increases Channel Capacity Per Dynamic
"... Abstract — We design a forest with nodes that represent orthogonal variable spreading factor (OVSF) sequences of different lengths (spreading codes of different lengths that can be used for multirate DSCDMA). In addition to the nondescendant OVSF property exhibited in wellknown treestructured g ..."
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Abstract — We design a forest with nodes that represent orthogonal variable spreading factor (OVSF) sequences of different lengths (spreading codes of different lengths that can be used for multirate DSCDMA). In addition to the nondescendant OVSF property exhibited in wellknown treestructured generation of sequences [1,2], the sequences represented by the nodes of our forest have useful properties that can be used to achieve multichannel communication (with a sequence providing a channel) with a lower total peaktomean envelope power ratio (PMEPR). These OSVF sequences grouped by our forest structure also have properties that facilitate symbolbysymbol adaptation of the symbol duration in multirate CDMA systems. For example, certain lineages in the forest have the property that any pair of code sequences in the same lineage are shift orthogonal to each other, with the unit shift length being that of the shorter sequence. We present the foreststructured generation of the sequences (spreading codes) and their properties. Index Terms — CDMA, orthogonal variable spreading factor code, peaktomean power ratio, wireless networks. I.
Performance of ReedMuller and Kerdock Coded MCCDMA System with Nonlinear Amplifier
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Hadamard Coded Modulation for Visible Light Communications
"... Visible light communication (VLC) systems using the indoor lighting system to also provide downlink communications require high average optical powers in order to satisfy the illumination needs. This can cause high amplitude signals common in higherorder modulation schemes to be clipped by the pea ..."
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Visible light communication (VLC) systems using the indoor lighting system to also provide downlink communications require high average optical powers in order to satisfy the illumination needs. This can cause high amplitude signals common in higherorder modulation schemes to be clipped by the peak power constraint of the light emitting diode (LED) and lead to high signal distortion. In this paper we introduce Hadamard coded modulation (HCM) to achieve low error probabilities in LEDbased VLC systems needing high average optical powers. This technique uses a fast WalshHadamard transform (FWHT) to modulate the data as an alternative modulation technique to orthogonal frequency division multiplexing (OFDM). HCM achieves a better performance for high illumination levels because of its small peak to average power ratio (PAPR). The power efficiency of HCM can be improved by reducing the DC part of the transmitted signals without losing any information. The resulting socalled DCreduced HCM (DCRHCM) is well suited to environments requiring dimmer lighting as it transmits signals with lower peak amplitudes compared to HCM, which are thus subject to less nonlinear distortion. Interleaving can be applied to HCM to make the resulting signals more resistant against intersymbol interference (ISI) in dispersive VLC links.