Optimum filter bandwidths for optically preamplified NRZ receivers

We present a comprehensive treatment of optically preamplified direct detection receivers for non-return-to-zero (NRZ) and return-to-zero (RZ) on/off keying modulation, taking into account the influence of different (N)RZ optical pulse shapes, specified at the receiver input, and filter transfer functions; optical Fabry-Perot filters (FPFs) and Bragg gratings as well as electrical fifth-order Bessel and first-order RC low-pass filters are considered. We determine optimum optical and electrical filter bandwidths and analyze the impact of bandwidth deviations on receiver sensitivity. Optimum receiver performance relies on a balance between noise and intersymbol interference (ISI) for NRZ transmission, while for RZ reception detection noise has to be traded against filter-induced signal energy rejection. Both for NRZ and 33% duty cycle RZ, optical filter bandwidths of around twice the data rate are found to be optimum. Receivers using RZ coding are shown to closely approach the quantum limit, and thus to outperform NRZ-based systems by several decibels. We further analyze the impact of important degrading effects on receiver sensitivity and optimum receiver bandwidths, including receiver noise, finite extinction ratio, chirp, and optical carrier frequency (or optical filter center frequency) fluctuations.

[1]  J. Cartledge.  Comparison of effective /spl alpha/-parameters for semiconductor Mach-Zehnder optical modulators , 1998 .

[2]  Eric A. Swanson,et al.  High-data-rate systems for space applications , 1995, Photonics West.

[3]  J.J.M. Binsma,et al.  Universality of the chirp-parameter of bulk active electro absorption modulators , 1998, 24th European Conference on Optical Communication. ECOC '98 (IEEE Cat. No.98TH8398).

[4]  P. J. Winzer,et al.  Sensitivity enhancement of optical receivers by impulsive coding , 1999 .

[5]  J. S. Lee,et al.  Bit-error-rate analysis of optically preamplified receivers using an eigenfunction expansion method in optical frequency domain , 1994 .

[6]  R. Kashyap.  Fiber Bragg Gratings , 1999 .

[7]  Ira Jacobs.  Effect of optical amplifier bandwidth on receiver sensitivity , 1990, IEEE Trans. Commun..

[8]  Leonid G. Kazovsky,et al.  Optical Fiber Communication Systems , 1996 .

[9]  W. Leeb,et al.  The potential of return-to-zero coding in optically amplified lasercom systems , 1999, 1999 IEEE LEOS Annual Meeting Conference Proceedings. LEOS'99. 12th Annual Meeting. IEEE Lasers and Electro-Optics Society 1999 Annual Meeting (Cat. No.99CH37009).

[10]  S. L. Danielsen,et al.  Detailed noise statistics for an optically preamplified direct detection receiver , 1995 .

[11]  E. Desurvire.  Erbium-doped fiber amplifiers , 1994 .

[12]  L. Boivin,et al.  Receiver sensitivity for optically amplified RZ signals with arbitrary duty circle , 1999 .

[13]  D. Marcuse.  Derivation of analytical expressions for the bit-error probability in lightwave systems with optical amplifiers , 1990 .

[14]  Shlomo Shamai,et al.  Performance bounds and cutoff rates of quantum limited OOK with optical amplification , 1994, Proceedings of 1994 IEEE International Symposium on Information Theory.

[15]  Helio Waldman,et al.  Error-Rate Patterns for the Modeling of Optically Amplified Transmission Systems , 1997, IEEE J. Sel. Areas Commun..

[16]  Mark Leeson,et al.  Principles of Lightwave Communications , 1996 .

[17]  S. W. Granlund,et al.  Optical Preamplifier Receivers: Application to Long-Haul Digital Transmission , 1994 .

[18]  Kenji Kawano,et al.  Chirping characteristic and frequency response of MQW optical intensity modulator , 1992 .

[19]  L. Ribeiro,et al.  Performance evaluation of EDFA preamplified receivers taking into account intersymbol interference , 1995 .

[20]  E.A. Swanson,et al.  High sensitivity optically preamplified direct detection DPSK receiver with active delay-line stabilization , 1994, IEEE Photonics Technology Letters.

[21]  S. Chinn.  Error-rate performance of optical amplifiers with Fabry-Perot filters , 1995 .

[22]  Peter J. Winzer.  Performance estimation of receivers corrupted by optical noise , 2001 .

[23]  Roy S. Bondurant,et al.  Demonstration of return-to-zero signaling in both OOK and DPSK formats to improve receiver sensitivity in an optically preamplified receiver , 1999, 1999 IEEE LEOS Annual Meeting Conference Proceedings. LEOS'99. 12th Annual Meeting. IEEE Lasers and Electro-Optics Society 1999 Annual Meeting (Cat. No.99CH37009).

[25]  Peter J. Winzer,et al.  Role of amplified spontaneous emission in optical free-space communication links with optical amplification: impact on isolation and data transmission and utilization for pointing, acquisition, and tracking , 1999, Photonics West.

[26]  F. Koyama,et al.  Frequency chirping in external modulators , 1988 .

[27]  W. Leeb,et al.  Bit error probability reduction in direct detection optical receivers using RZ coding , 2001 .

[28]  M. Teich,et al.  Fundamentals of Photonics , 1991 .

[29]  David E. Johnson,et al.  A handbook of active filters , 1980 .

[30]  I. Monroy,et al.  Bit error evaluation of optically preamplified direct detection receivers with Fabry-Perot optical filters , 1997 .

[31]  Martin Pfennigbauer,et al.  Significance of chirp parameter for direct-detection free-space laser communication , 2001, SPIE LASE.

[32]  P. Henry.  Error-rate performance of optical amplifiers , 1989 .

[33]  C. Lawetz,et al.  Performance of optically preamplified receivers with Fabry-Perot optical filters , 1996 .

[34]  L. Boivin,et al.  Receiver sensitivity improvement by impulsive coding , 1997, IEEE Photonics Technology Letters.

[35]  Miguel A. Muriel,et al.  Phase reconstruction from reflectivity in fiber Bragg gratings , 1997 .

[36]  N. Olsson.  Lightwave systems with optical amplifiers , 1989 .

[37]  T. Erdogan.  Fiber grating spectra , 1997 .

[38]  I. Tafur Monroy.  Optically preamplified receiver with low quantum limit , 1999 .

[39]  J. C. Livas.  HIGH SENSITIVITY OPTICALLY PREAMPLIFIED 10 Gb/s RECEIVERS , 1996 .

[40]  Eiichi Sano,et al.  Chapter 11 – Advances in High Bit-Rate Transmission Systems , 1997 .