Results 1  10
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16
New peaktoaverage powerratio reduction algorithms for multicarrier communications
 IEEE Trans. on Circuits and Systems I: Regular Papers
, 2004
"... Abstract — New peaktoaverage powerratio (PAPR) reduction algorithms for orthogonal frequencydivision multiplexing (OFDM) systems are investigated in a probabilistic framework. Specifically, derandomization algorithms based on the Chernoff bound for PAPR reduction are developed by applying the so ..."
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Cited by 21 (2 self)
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Abstract — New peaktoaverage powerratio (PAPR) reduction algorithms for orthogonal frequencydivision multiplexing (OFDM) systems are investigated in a probabilistic framework. Specifically, derandomization algorithms based on the Chernoff bound for PAPR reduction are developed by applying the socalled conditional probability method. Our simulations demonstrate that the proposed algorithms outperform several existing algorithms and the computational complexity of the proposed algorithms is found to be significantly less than that of existing algorithms. I.
A multidimensional approach to the construction and enumeration of Golay complementary sequences
 J. Combin. Theory (A
, 2006
"... We argue that a Golay complementary sequence is naturally viewed as a projection of a multidimensional Golay array. We present a threestage process for constructing and enumerating Golay array and sequence pairs: 1. construct suitable Golay array pairs from lowerdimensional Golay array pairs; 2. a ..."
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Cited by 14 (8 self)
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We argue that a Golay complementary sequence is naturally viewed as a projection of a multidimensional Golay array. We present a threestage process for constructing and enumerating Golay array and sequence pairs: 1. construct suitable Golay array pairs from lowerdimensional Golay array pairs; 2. apply transformations to these Golay array pairs to generate a larger set of Golay array pairs; and 3. take projections of the resulting Golay array pairs to lower dimensions. This process greatly simplifies previous approaches, by separating the construction of Golay arrays from the enumeration of all possible projections of these arrays to lower dimensions. We use this process to construct and enumerate all 2 hphase Golay sequences of length 2 m obtainable under any known method, including all 4phase Golay sequences obtainable from the length 16 examples given in 2005 by Li and Chu [12]. 1
New Constructions of General QAM Golay Complementary Sequences
, 2012
"... There have been five constructions (Case I to Case V) of 64QAM Golay complementary sequences (GCSs), of which the Case IV and Case V constructions were identified by Chang, Li, and Hirata in 2010. The Generalized Cases IIII constructions for 4qQAM (q ≥ 1) GCSs were additionally proposed by Li. In ..."
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Cited by 6 (2 self)
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There have been five constructions (Case I to Case V) of 64QAM Golay complementary sequences (GCSs), of which the Case IV and Case V constructions were identified by Chang, Li, and Hirata in 2010. The Generalized Cases IIII constructions for 4qQAM (q ≥ 1) GCSs were additionally proposed by Li. In this paper, the Generalized Case IV and Generalized Case V constructions for 4qQAM (q> = 3) GCSs are proposed using selected Gaussian integer pairs, each of which contains two distinct Gaussian integers with identical magnitude and which are not conjugate with each other.
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.
Generalised complementary arrays
 Lecture Notes in Computer Science, LNCS 7089
, 2011
"... Abstract. We present a generalised setting for the construction of complementary array pairs and its proof, using a unitary matrix notation. When the unitaries comprise multivariate polynomials in complex space, we show that four definitions of conjugation imply four types of complementary pair typ ..."
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Cited by 3 (2 self)
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Abstract. We present a generalised setting for the construction of complementary array pairs and its proof, using a unitary matrix notation. When the unitaries comprise multivariate polynomials in complex space, we show that four definitions of conjugation imply four types of complementary pair types I, II, III, and IV. We provide a construction for complementary pairs of types I, II, and III over {1, −1}, and further specialize to a construction for all known 2 × 2 ×... × 2 complementary array pairs of types I, II, and III over {1, −1}. We present a construction for typeIV complementary array pairs, and call them Rayleigh quotient pairs. We then generalise to complementary array sets, provide a construction for complementary sets of types I, II, and III over {1, −1}, further specialize to a construction for all known 2 × 2 ×... × 2 complementary array sets of types I, II, and III over {1, −1}, and derive closedform Boolean formulas for these cases.
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
Recursive Construction of 16QAM SuperGolay Codes for OFDM systems
 the Proc. of IEEE Int’l. Conf. on Comm., ICC
, 2003
"... Abstract — In this paper, the Peak to mean Envelope Power (PMEPR) of the OFDM codes generated from an 16QAM constellation is discussed. Maintaining the same level of error correction properties, these codes achieve higher information rate. A new set of 16QAM Golay sequences having PMEPR bounded up ..."
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Abstract — In this paper, the Peak to mean Envelope Power (PMEPR) of the OFDM codes generated from an 16QAM constellation is discussed. Maintaining the same level of error correction properties, these codes achieve higher information rate. A new set of 16QAM Golay sequences having PMEPR bounded up to 3dB is defined. Many recursive structures are found to generate Super Golay sequences. The recursive algorithm is started by a generalized realization of an 16QAM sequence as a weighted sum of two QPSK sequences. The coding rate and information rate of the generated code is compared to similar works.
A Generalized Construction of OFDM MQAM Sequences With Low PeaktoAverage Power Ratio
, 2010
"... ..."
A New Construction of 16QAM Codewords with
"... Abstract — We present a novel construction of 16QAM codewords of length n =2 k. The number of constructed codewords is 16 2 ×[4 k−1 ×k−k+1]. When these constructed codewords are utilized as a code in OFDM systems, their peaktomean envelope power ratios (PMEPR) are bounded above by 3.6. The princi ..."
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Abstract — We present a novel construction of 16QAM codewords of length n =2 k. The number of constructed codewords is 16 2 ×[4 k−1 ×k−k+1]. When these constructed codewords are utilized as a code in OFDM systems, their peaktomean envelope power ratios (PMEPR) are bounded above by 3.6. The principle of our scheme is illustrated with a four subcarrier example. Index Terms — Extended RudinShapiro construction, orthogonal frequency division multiplexing (OFDM), peaktomean envelope power ratio (PMEPR). I.