Orthogonal Chirp Division Multiplexing for Coherent Optical Fiber Communications

Ouyang, Xing; Zhao, Jian

doi:10.1109/jlt.2016.2598575

Cited by 55 publications

(24 citation statements)

References 49 publications

(43 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…This transformation describes the process of coherent addition in Talbot array illuminators [31,35] and noiseless pulse amplification [36]. Transform T t t t , restricted to Talbot orders of the form 1/q, has been used to define orthogonal multiplexing schemes [2], and its combination with modulation has also led to the design of compact processors for the passive, analog construction of the DFT of repetitive pulse sequences [32].…”

Section: Talbot Circulant Discrete Signal Processing and Generation Omentioning

confidence: 99%

“…These sequences have found practical application in several contexts. To name a few, the unitary transformation (3) can be employed to construct equalizers or multiplexing schemes where the power of each of the L input channels is smeared among the L output channels [2,3]. ZAC or CAZAC sequences may be used to define coded waveforms, so that the perfect autocorrelation (1) allows for its decorrelation in noisy environments.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Perfect phase-coded pulse trains generated by Talbot effect

Fernández-Pousa

2018

Applied Mathematics and Nonlinear Sciences

View full text Add to dashboard Cite

A perfect phase sequence is a finite and ordered set of constant-amplitude complex numbers whose periodic autocorrelation vanishes at any non-zero time shift. They find multiple applications in science an engineering as phase-coded waveforms, where the sequence defines the relative phases within a burst of electromagnetic or acoustic pulses. We show how a physical propagation effect, the so-called fractional Talbot phenomenon, can be used to generate pulse trains coded according to these sequences. The mathematical description of this effect is first reviewed and extended, showing its close relationship with Gauss perfect phase sequences. It is subsequently shown how it leads to a construction of Popović’s Generalized Chirp-Like (GCL) sequences. Essentially, a set of seed pulses with prescribed amplitude and phase levels, cyclically feeds a linear and dispersive medium. At particular values of the propagation length, multiple pulse-to-pulse interference induced by dispersion passively creates the sought-for pulse trains composed of GCL sequences, with the additional property that its repetition rate has been increased with respect to the seed pulses. This observation constitutes a novel representation of GCL sequences as the result of dispersive propagation of a seed sequence, and a new route for the practical implementation of perfect phase-coded pulse waveforms using Talbot effect.

show abstract

Section: Talbot Circulant Discrete Signal Processing and Generation Omentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Perfect phase-coded pulse trains generated by Talbot effect

Fernández-Pousa

2018

Applied Mathematics and Nonlinear Sciences

View full text Add to dashboard Cite

show abstract

“…In the OCDM system, the operational process of IDFnT and DFnT should be respectively performed at the transmitter and the receiver. To be compatible with the prevalent OFDM communication system, a compatible OCDM scheme based on OFDM communication architecture is proposed in [15], this scheme only has the operation process of IDFT and DFT at the transceiver or receiver. This paper is also based on the OCDM scheme proposed in [15].…”

Section: B Anti-multipath Ocdm Schemementioning

confidence: 99%

“…9(b): at first, after conversion to the baseband signal, the received signal is cross-correlated with the local dual HFM signal, the correlation peak is determined to complete the frame synchronization [22], and the Doppler shift caused by relative motion is compensated by Doppler estimation and phase correction; then, the obtained data are transferred to the data pick-based rake receiver, and each data block is subjected to OCDM demodulation under the setting of each rake finger; finally, the demodulated data is subjected to CRC check and data pick to obtain the final information data. The OCDM demodulation part adopts a single-tap FDE for the demodulation structure in [15]. The data block to be demodulated is r, and DFT processing for r can obtain y before FDE.…”

Section: B Anti-multipath Ocdm Schemementioning

confidence: 99%

“…An underloaded OCDM scheme is proposed and leads to signal-to-noise ratio (SNR) gain but at the expense of the decreasing data rate [14]. Compared with the traditional OFDM system, the OCDM system offers better anti-interference ability while maintaining the same spectral efficiency [15]. However, the reflection of the sea surface, seabed, and obstacles, as well as inhomogeneity within the ocean, lead to multipath characteristics of the underwater acoustic channel, especially in shallow waters, that can reach tens or even hundreds of milliseconds [16].…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Anti-Multipath Orthogonal Chirp Division Multiplexing for Underwater Acoustic Communication

Zhu

et al. 2020

IEEE Access

View full text Add to dashboard Cite

Multipath due to reflections of the sea surface, seabed, and obstacles, as well as inhomogeneity within the ocean, is an important characteristic of underwater acoustic channels. Mutual interference among multiple paths causes severe amplitude fading and frequency selective fading. The guard interval is an effective anti-multipath method, but an excessively long guard interval will reduce the data rate of multicarrier underwater acoustic communication. In this paper, we propose a new anti-multipath multi-carrier communication method based on orthogonal chirp division multiplexing (OCDM) that uses chirp signals for carrier modulation. As OCDM exploits the multipath components for diversity gain, the system robustness is improved. The new method also adds a data pick-based rake receiver for maintaining good communication performance, even at short guard intervals. We detail the implementation and parameter selection of the antimultipath OCDM system and compare its performance with the traditional orthogonal frequency division multiplexing (OFDM) scheme using simulations; under a severe multipath simulation condition (the delay spread is longer than the guard interval), the anti-multipath OCDM achieves a bit error rate (BER) of 10 −6 , while the OFDM has a BER floor of 10 −3. The simulation results verify the feasibility of the proposed method and the superiority of its anti-multipath performance. INDEX TERMS Multipath channels, orthogonal chirp division multiplexing, underwater acoustic communication.

show abstract