ZCZ Sequence Research Articles

A Direct Construction of ZCZ Sequences With Low Peak-to-Average Power Ratio

A Direct Construction of ZCZ Sequences With Low Peak-to-Average Power Ratio

New construction of optimal ZCZ sequence sets with inter-set zero cross-correlation zone

New construction of optimal ZCZ sequence sets with inter-set zero cross-correlation zone

A new construction of almost-optimal multiple ZCZ sequence sets for multi-cell QS-CDMA system

A new construction of almost-optimal multiple ZCZ sequence sets for multi-cell QS-CDMA system

A New Construction of Asymmetric ZCZ Sequence Sets

A New Construction of Asymmetric ZCZ Sequence Sets

Sequences With Good Correlations Based on Circular Florentine Arrays

Sequences and their correlation properties have been extensively studied due to their broad applications. In this paper, we develop a connection between sequences and well-studied combinatorial objects, circular Florentine arrays. This connection allows us to derive two types of sequences with good correlation properties. The first type consists of sequences having optimal correlation with respect to the Sarwate bound. Our constructions are based on perfect polyphase sequences. The number of perfect sequences with optimal correlation depends on the existence of circular Florentine arrays, which improves the previous known results. The second type is about multiple ZCZ sequence sets with low inter-set cross-correlation. Each generated ZCZ sequence set is optimal with respect to the Tang-Fan-Matsufuji bound, and each sequence in each set is perfect. In addition, any two sequences from distinct ZCZ sequence sets possess optimal inter-set cross-correlation with respect to the Sarwate bound. Compared with the previous results, the number of ZCZ sequence sets with optimal inter-set cross-correlation property is improved, because of the existence of circular Florentine arrays.

Construction of Multiple Optimal Polyphase Zero Correlation Zone Sequence Sets With Inter-Set Zero Cross-Correlation Zone

Based on DFT matrices and no-hit-zone (NHZ) frequency hopping sequence sets, a construction of multiple optimal polyphase zero correlation zone sequence sets with inter-set zero cross-correlation zone (ZCCZ) is proposed. The parameters of each subset are optimal, and arbitrary two sequences from different subsets have the same inter-set ZCCZ. Furthermore, new NHZ frequency hopping sequence sets are proposed, which can be used in the construction of multiple polyphase ZCZ sequence sets with inter-set ZCCZ. The resultant sequence sets presented in this letter can be applied to multi-cell QS-CDMA systems.

Doppler Influence on Waveform Orthogonality in 79 GHz MIMO Phase-Coded Automotive Radar

Utilization of phase-coded waveforms in automotive MIMO radars for short to medium range applications is studied. Performances of three most-promising binary code families (Gold, APAS and ZCZ sequences) are compared. Design trade-offs of practical implementation of phased-coded waveforms for MIMO radar are analyzed for the first time for a possible future System on Chip implementation. Orthogonality of the waveforms in case of moving targets is analyzed. The implications of the code properties for the Range-Doppler map, as well as the Range-Angular map, are pointed out. Doppler frequency shift impact on such performance indicators as the target peak power and range sidelobe levels in the range-Doppler plane, as well as the range and azimuth sidelobe behavior, and the angular error in the azimuthal plane have been comprehensively studied for the first time. It is shown that the time-staggered transmit scheme with autocorrelation properties only (while introducing azimuthal errors) results in improved performance compared to code division multiplexing with auto- and cross-correlation properties.

Construction of Asymmetric Gaussian Integer ZCZ Sequence Sets

Construction of Asymmetric Gaussian Integer ZCZ Sequence Sets

A Plural CDMA System with Zero Correlation Zone Codes in Emergency Communication

This paper proposes a plural ZCZ-CDMA system with binary frequency keying modulation. It is shown that this system achieves more advantageous bit error rate characteristics over Rayleigh fading channels than those of ASK or BPSK modulation scheme and have more advantageous for comprehensive spectral efficiency than BFSK modulation scheme. From the viewpoints of further improving their error rate performance over Rayleigh fading channel, this research on BFSK is conducted while introducing new techniques such as use of fading-independency between two keying frequencies to which a pair of balanced ZCZ sequences is allocated, and use of combining techniques with two demodulated outputs obtained by the two ZCZ sequences. Performance formulation and simulation on the proposed system are conducted under the comparison with the other ZCZ-CDMA systems or CDMA systems using the other codes. It will be proved that considerable improvement is achieved with the proposed system.

An asymmetric ZCZ sequence set with inter-subset uncorrelated property and flexible ZCZ length

In this paper, we propose a novel method for constructing new uncorrelated asymmetric zero correlation zone (UA-ZCZ) sequence sets by interleaving perfect sequences. As a type of ZCZ sequence set, an A-ZCZ sequence set consists of multiple sequence subsets. Different subsets are correlated in conventional A-ZCZ sequence set but uncorrelated in our scheme. In other words, the cross-correlation function (CCF) between two arbitrary sequences which belong to different subsets has quite a large zero cross-correlation zone (ZCCZ). Analytical results demonstrate that the UA-ZCZ sequence set proposed herein is optimal with respect to the upper bound of ZCZ sequence set. Specifically, our scheme enables the flexible selection of ZCZ length, which makes it extremely valuable for designing spreading sequences for quasi-synchronous code-division multiple-access (QS-CDMA) systems.

New Constructions of Multiple Binary ZCZ Sequence Sets with Inter-Set Zero Cross-Correlation Zone

New Constructions of Multiple Binary ZCZ Sequence Sets with Inter-Set Zero Cross-Correlation Zone

Asymmetric ZCZ Sequence Sets with Inter-Subset Uncorrelated Sequences via Interleaved Technique

Asymmetric ZCZ Sequence Sets with Inter-Subset Uncorrelated Sequences via Interleaved Technique

Families of asymmetric sequence pair set with zero‐correlation zone via interleaved technique

An asymmetric zero-correlation zone (A-ZCZ) sequence pair set is a ZCZ sequence pair set consisting of multiple ZCZ sequence pair subsets. Two arbitrary sequence pairs which belong to different subsets should have a large zero cross-correlation zone (ZCCZ) in the A-ZCZ sequence pair set. Additionally, each subset is a typical ZCZ sequence pair set. The proposed A-ZCZ sequence pair sets can be generated based on interleaved technique from perfect sequence or perfect sequence pair of length P = Nmk with N ≥ 1, m ≥ 1, k > 1. The new A-ZCZ sequence pair sets are applied to quasi-synchronous code-division multiple-access (QS-CDMA) systems and it can hypothetically achieve larger ZCCZ than typical ZCZ sequence pair sets, as well as eliminating both multiple access and multipath interference in the QS-CDMA system.

A Compact Matched Filter Bank for a Mutually Orthogonal ZCZ Sequence Set Consisting of Ternary Sequence Pairs

A Compact Matched Filter Bank for a Mutually Orthogonal ZCZ Sequence Set Consisting of Ternary Sequence Pairs

A Novel Construction of Asymmetric ZCZ Sequence Sets from Interleaving Perfect Sequence

A Novel Construction of Asymmetric ZCZ Sequence Sets from Interleaving Perfect Sequence

A Generic Construction of Generalized Chirp-Like Sequence Sets with Optimal Zero Correlation Property

In this letter, a generic construction of optimal generalized chirp-like ZCZ sequence sets with reduced alphabet size is presented. Further, we can obtain multiple optimal quaternary ZCZ sequence sets with good inter-set cross-correlation property within the zero correlation zone, which outperforms the binary and ternary counterparts.

Extension of Methods for Constructing Polyphase Asymmetric ZCZ Sequence Sets

Extension of Methods for Constructing Polyphase Asymmetric ZCZ Sequence Sets

Improved Successive Interference Cancellation for MIMO/UWB-Based Wireless Body Area Network

In body area networks, various sensors are attached to clothing or on the body or even implanted under the skin. The sensors measure such as heart beat, the record of prolonged electrocardiogram, blood pressure, and so on. In this paper, an improved Successive interference cancellation (SIC) scheme based on zero correlation zone sequences is proposed. Here ZCZ is used as a random code for TH PPM UWB system. Nodes in a WBAN are connected through wireless communication channel within a very close range. The decrease in internode distance leads to interference between devices. To reduce this interference, an enhanced successive interference cancellation scheme based on ZCZ with optimal ordering is adopted. Because of zero correlation property of ZCZ, the performance of TH PPM UWB system through WBAN channel with ZCZ sequences outperforms performance of existing zero correlation duration code. In this paper, performance of UWB system for various modulation schemes are compared. Performance of UWB/MIMO (<svg style="vertical-align:-0.3135pt;width:32.700001px;" id="M1" height="11.075" version="1.1" viewBox="0 0 32.700001 11.075" width="32.700001" xmlns="http://www.w3.org/2000/svg"> <g transform="matrix(1.25,0,0,-1.25,0,11.075)"> <g transform="translate(72,-63.14)"> <text transform="matrix(1,0,0,-1,-71.95,63.5)"> <tspan style="font-size: 12.50px; " x="0" y="0">2</tspan> <tspan style="font-size: 12.50px; " x="9.0271664" y="0">×</tspan> <tspan style="font-size: 12.50px; " x="19.804752" y="0">2</tspan> </text> </g> </g> </svg>) system employing SIC with optimal ordering using ZCZ codes also compared with pseudorandom (PN) and ZCD codes. Simulation results are obtained using sample biological functions as input to the proposed TH PPM UWB/MIMO (<svg style="vertical-align:-0.3135pt;width:32.700001px;" id="M2" height="11.075" version="1.1" viewBox="0 0 32.700001 11.075" width="32.700001" xmlns="http://www.w3.org/2000/svg"> <g transform="matrix(1.25,0,0,-1.25,0,11.075)"> <g transform="translate(72,-63.14)"> <text transform="matrix(1,0,0,-1,-71.95,63.5)"> <tspan style="font-size: 12.50px; " x="0" y="0">2</tspan> <tspan style="font-size: 12.50px; " x="9.0271664" y="0">×</tspan> <tspan style="font-size: 12.50px; " x="19.804752" y="0">2</tspan> </text> </g> </g> </svg>) system with m-ZCZ codes in WBAN environment with multiple devices.

A New Method for Constructing Asymmetric ZCZ Sequence Sets

A New Method for Constructing Asymmetric ZCZ Sequence Sets

Zero-Cross-Correlation Properties of Asymmetric ZCZ Sequence Sets

Zero-Cross-Correlation Properties of Asymmetric ZCZ Sequence Sets