Topic
Bessel filter
About: Bessel filter is a research topic. Over the lifetime, 656 publications have been published within this topic receiving 16808 citations.
Papers published on a yearly basis
Papers
More filters
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TL;DR: The grey-coded systems outperformed the differential- coded systems regarding optical signal-to-noise ratio requirement, receiver sensitivity, and transmission distance and are compared to the respective differential-coded modulation formats.
Abstract: In this article the performance of grey-coded advanced optical modulation formats is evaluated on a single-channel high-speed long-haul optical communication link and are compared to the respective differential-coded modulation formats. Polarisation division multiplexed optical in-phase quadrature modulator (IQM) structure and homodyne detection scheme are used to realise 100 Gbps quadrature phase-shift keying (QPSK), 120 Gbps 16-ary quadrature amplitude modulation (16-QAM), 360 Gbps 32-QAM and 480 Gbps 64-QAM modulation formats. Advanced digital signal processing unit with various pre-processing and recovery stages such as direct current blocking, normalisation, low-pass Bessel filter, resampling, quadrature imbalance compensation, chromatic dispersion compensation, non-linear compensation, timing recovery, adaptive equalisation, down-sampling, frequency offset estimation, and carrier phase estimation is used at the receiving end to compensate for signal impairments during propagation. Maximum transmission distances of 7200, 1050, 560, and 360 km have been achieved at an acceptable bit error rate for QPSK, 16-QAM, 32-QAM, and 64-QAM, respectively. The grey-coded systems outperformed the differential-coded systems regarding optical signal-to-noise ratio requirement, receiver sensitivity, and transmission distance.
13 citations
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21 Nov 2004TL;DR: In this article, the authors presented the methodology how to vary in time values /spl omega/sub 0i/ = /spl Omega/sub/0i/(t) selected links of a structure of low-pass Bessel filters.
Abstract: The paper presents the methodology how to vary in time values /spl omega//sub 0i/ = /spl omega//sub 0i/(t) selected links of a structure of low-pass Bessel filters In examinations of the filters a significant shortening of the transient state is achieved at the cost of slight increase in the oscillations It allows shortening time intervals of filtered signals Typical filtration results are presented which simulations of selected structures of filters with varying parameters obtain
13 citations
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TL;DR: In this article, the authors demonstrate the generation of 10-Gb/s optical duobinary signals from 2.5-GHz Mach-Zehnder (MZ) modulators without using Duobinary encoders.
Abstract: We demonstrate the generation of 10-Gb/s optical duobinary signals from 2.5-Gb/s Mach-Zehnder (MZ) modulators without using duobinary encoders. The absence of the duobinary encoder not only permits the monolithic integration of electrical components but also reduces the required bandwidth of MZ modulators as low as 3 GHz. However, it might induce pattern-length dependency to the signals. Our demonstration, performed with four 2.5-Gb/s MZ modulators obtained from two different vendors, shows that the receiver sensitivity of better than -33.8 dBm is achieved at a pseudorandom bit sequence length of 2/sup 31/-1 when dispersion of 1200 /spl sim/ 1700 ps/nm is applied to the signals. This is 1.6 dB poorer than using an 8.5-GHz bandwidth MZ modulator along with a 3.0-GHz Bessel filter. Therefore, this scheme can be used to implement cost-effective 10-Gb/s optical duobinary transmitters without significant performance degradation.
13 citations
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17 Nov 2008TL;DR: It is shown that even though Bessel filters pass more adjacent channel interference, they result in a significantly lower Bit Error Rate (BER) and insertion loss than the other filter types.
Abstract: This paper investigates the Bit Error Rates (BER) obtained using different filter types for RF front ends for WCDMA-UMTS mobile radio systems. Most Base Stations use Chebychev or Cauer-Chebychev filters. This paper compares the use of Bessel, Butterworth and Chebychev filters for use as single channel filters in a WCDMA-UMTS radio system. It is shown that even though Bessel filters pass more adjacent channel interference, they result in a significantly lower Bit Error Rate (BER) and insertion loss than the other filter types.
13 citations
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TL;DR: The theory indicates that for an nth-order Besselbeam, the second-harmonic beam is nearly diffraction-free in the radial direction and behaves as a Bessel beam of the order 2n, and that the axial pressure amplitude is proportional to the square root of propagation distance.
Abstract: We investigate the second-harmonic generation of the nth-order Bessel beam in the nonlinear medium. The analysis is based on the Khokhlov-Zabolotskaya-Kuznetsov wave equation under the second-order approximation in nonlinear acoustics. The theory indicates that for an nth-order Bessel beam, the second-harmonic beam is nearly diffraction-free in the radial direction and behaves as a Bessel beam of the order 2 n, and that the axial pressure amplitude is proportional to the square root of propagation distance. A variety of applications in many fields of nonlinear acoustics and nonlinear optics is expected.
13 citations