Hugo Carrer | Universidad Nacional de Córdoba (original) (raw)
Papers by Hugo Carrer
… , 2009. EAMTA 2009. Argentine School of, Jan 1, 2009
An 11Gb/s Equalizer is designed in 45nm CMOS to compensate for the losses in a 12" PCB trace. Amp... more An 11Gb/s Equalizer is designed in 45nm CMOS to compensate for the losses in a 12" PCB trace. Amplitude variations are compensated with a limiting amplifier that provides a constant swing to a digital phase detector. An offset cancellation loop is used to attenuate offset in the high gain stage.
The induced penalty of reduced-state Viterbi equalizers for dispersive optical transmission syste... more The induced penalty of reduced-state Viterbi equalizers for dispersive optical transmission systems is analyzed. We present the dispersion limits that can be compensated using a 2, 4, 8 and 16-states Viterbi detector. Introduction Electrical equalization techniques to compensate transmission impairments in intensity-modulation / direct-detection (IM/DD) optical systems have recently gained significant attention in the industry. The latest advances in integrated circuit technology have made the implementation of these techniques feasible at the speeds required in today's applications (10Gb/s or higher)[1]. The maximum likelihood sequence estimation (MLSE) technique outperforms others, like decision feedback equalization (DFE) [2]-[4], because of its capacity to deal with the nonlinear nature and the nongaussian signal-dependent noise of the optical system [5].
Latin American applied research Pesquisa aplicada latino americana = Investigación aplicada latinoamericana
Maximum likelihood sequence estimation (MLSE) has been proposed in earlier literature to combat t... more Maximum likelihood sequence estimation (MLSE) has been proposed in earlier literature to combat the effects of nonlinear dispersion in intensity modulation/direct detection (IM/DD) optical channels. In this paper, we develop a theory of the bit error rate (BER) of MLSE-based IM/DD receivers operating in the presence of nonlinear dispersion and amplified spontaneous emission (ASE) noise. We focus on long haul or metro links spanning several hundred kilometers of single mode fibers with optical amplifiers. Numerical results show a close agreement between the predictions of the theory and computer simulations.
IEEE Global Telecommunications Conference, 2004. GLOBECOM '04., 2004
Chromatic dispersion (CD) and polarization mode dispersion (PMD) severely limit the performance o... more Chromatic dispersion (CD) and polarization mode dispersion (PMD) severely limit the performance of optical transmission systems operating at data rates of 10 Gb/s and beyond. Electrical equalization techniques have been proposed to compensate dispersion in both coherent and intensity modulation/directdetection (IM/DD) systems. The former benefit from the fact that a complete compensation with zero penalty is possible, at least in principle, whereas in the latter the loss of phase information caused by the direct detection process results in a nonzero dispersion penalty even when optimal equalizers are used. In this paper, we investigate the combined adaptive digital equalization of all-order PMD, CD, and laser phase noise in highspeed coherent optical transmission systems. Although electrical equalization in coherent optical transmission systems has been addressed by previous , equalization of the combined effects of CD, PMD, and laser phase noise has not been reported so far. Simultaneous equalization of these impairments is particularly important in modulation systems that exploit polarization to increase the modulation efficiency, such as the joint polarization modulation and M-ary differential phase shift keying (JPMDPSK) system described in [4]. We propose a novel 4-dimensional equalizer structure for JPMDPSK systems. The specific example considered in this paper is 40 Gb/s transmission with a 10 GBaud symbol rate, using DQPSK modulation on each axis of polarization. Our results show that the new fourdimensional equalizer can compensate channel dispersion of up to 1000 km of standard single-mode fiber, with less than 3 dB penalty in signal to noise ratio (SNR). This is a dramatic improvement over 40 Gb/s IM/DD systems, even when they use electrical [5] or optical [6] equalization. The feasibility of the very large scale integration (VLSI) of coherent receivers in current technology is also discussed.
IEEE Global Telecommunications Conference, 2004. GLOBECOM '04., 2004
traditional channel codes designed for transmissions over AWGN channels, in combination with SISO... more traditional channel codes designed for transmissions over AWGN channels, in combination with SISO front-end detectors, achieve asymptotically optimal performance in transmissions over IM/DD optical channels.
2008 IEEE International Conference on Communications, 2008
In this paper we present the architecture and experimental evaluation of a single-chip CMOS maxim... more In this paper we present the architecture and experimental evaluation of a single-chip CMOS maximum-likelihood sequence detection (MLSD) transceiver for electronic dispersion compensation (EDC) of multimode optical fibers (MMF) at 10Gb/s data rate. The primary application of this transceiver is the 10GBASE-LRM standard for 10Gb/s Ethernet over MMF [1]. Application to single-mode fiber (SMF) channels and/or other standards is also possible. Both optical module and line card applications are discussed. The architecture of the receiver is discussed in considerable depth, including implementation details. Extensive experimental results on several channels are presented. For the precursor, postcursor, and symmetric stressors specified by the 10GBASE-LRM standard we demonstrate receiver sensitivities of -14.84dBm, -14.37dBm, and -13.68dBm, respectively, in a line card application with 6 inches of electrical interconnect. These sensitivities exceed the requirements of the standard by 8.34dBo, 7.87dBo, and 7.68dBo 1 , respectively. Measured results on industry defined worst-case fibers and on nonstationary channels such as the dynamic stressor defined by the 10GBASE-LRM standard are also presented.
2011 IEEE Global Telecommunications Conference - GLOBECOM 2011, 2011
This paper introduces a new parallel carrier recovery architecture suitable for ultra-high speed ... more This paper introduces a new parallel carrier recovery architecture suitable for ultra-high speed intradyne coherent optical receivers (e.g., ≥ 40Gb/s). The proposed scheme combines a novel low-latency parallel digital phase locked loop (DPLL) with a feedforward carrier phase recovery (CPR) algorithm. The new low-latency parallel DPLL is designed to compensate not only frequency offset, but also frequency fluctuations such as those induced by mechanical vibrations.
2011 VII Southern Conference on Programmable Logic (SPL), 2011
This paper introduces a new low latency parallel processing digital carrier recovery (CR) archite... more This paper introduces a new low latency parallel processing digital carrier recovery (CR) architecture suitable for ultra-high speed intradyne coherent optical receivers (e.g. ≥ 100Gb/s). The proposed parallel scheme builds upon a novel digital phase locked loop (DPLL) architecture, which breaks the bottleneck of the feedback path. Thus, it is avoided the high latency introduced by the parallel processing implementation in the feedback loop of traditional DPLLs. Numerical results show that the bandwidth and the capture range of the new parallel DPLL are close to those achieved by a serial DPLL. This excellent behavior makes the proposed low latency parallel DPLL architecture an excellent choice for implementing high speed CR systems in both ASIC and FPGA platforms.
2006 IEEE International Conference on Communications, 2006
AbstractWe investigate the performance of maximum likelihood sequence estimation (MLSE) receiver... more AbstractWe investigate the performance of maximum likelihood sequence estimation (MLSE) receiver in the presence of the impairments from both the pulse carver-data modulator timing misalignment (TM) and polarization mode dispersion (PMD) in optically amplified ...
OFC/NFOEC 2008 - 2008 Conference on Optical Fiber Communication/National Fiber Optic Engineers Conference, 2008
We demonstrate that InP modulators together with 1 sample/bit MLSE gives equivalent performance t... more We demonstrate that InP modulators together with 1 sample/bit MLSE gives equivalent performance to linear electro-optic Mach-Zehnder modulators combined with oversampled MLSE, potentially providing significant reduction in power dissipation and footprint.
The Ninth International Conference onCommunications Systems, 2004. ICCS 2004., 2004
We analyze the log-likelihood ratio (LLR) of the received signal yielded by a soft input/soft out... more We analyze the log-likelihood ratio (LLR) of the received signal yielded by a soft input/soft output (SISO) front-end decoder, in intensity modulation direct detection (IM/DD) optical channels operating in the presence of amplified spontaneous emission (ASE) noise. We focus on long haul or metro links spanning several hundred kilometers of single mode fibers with optical amplifiers. Unlike in AWGN channels
… , 2009. EAMTA 2009. Argentine School of, Jan 1, 2009
An 11Gb/s Equalizer is designed in 45nm CMOS to compensate for the losses in a 12" PCB trace. Amp... more An 11Gb/s Equalizer is designed in 45nm CMOS to compensate for the losses in a 12" PCB trace. Amplitude variations are compensated with a limiting amplifier that provides a constant swing to a digital phase detector. An offset cancellation loop is used to attenuate offset in the high gain stage.
The induced penalty of reduced-state Viterbi equalizers for dispersive optical transmission syste... more The induced penalty of reduced-state Viterbi equalizers for dispersive optical transmission systems is analyzed. We present the dispersion limits that can be compensated using a 2, 4, 8 and 16-states Viterbi detector. Introduction Electrical equalization techniques to compensate transmission impairments in intensity-modulation / direct-detection (IM/DD) optical systems have recently gained significant attention in the industry. The latest advances in integrated circuit technology have made the implementation of these techniques feasible at the speeds required in today's applications (10Gb/s or higher)[1]. The maximum likelihood sequence estimation (MLSE) technique outperforms others, like decision feedback equalization (DFE) [2]-[4], because of its capacity to deal with the nonlinear nature and the nongaussian signal-dependent noise of the optical system [5].
Latin American applied research Pesquisa aplicada latino americana = Investigación aplicada latinoamericana
Maximum likelihood sequence estimation (MLSE) has been proposed in earlier literature to combat t... more Maximum likelihood sequence estimation (MLSE) has been proposed in earlier literature to combat the effects of nonlinear dispersion in intensity modulation/direct detection (IM/DD) optical channels. In this paper, we develop a theory of the bit error rate (BER) of MLSE-based IM/DD receivers operating in the presence of nonlinear dispersion and amplified spontaneous emission (ASE) noise. We focus on long haul or metro links spanning several hundred kilometers of single mode fibers with optical amplifiers. Numerical results show a close agreement between the predictions of the theory and computer simulations.
IEEE Global Telecommunications Conference, 2004. GLOBECOM '04., 2004
Chromatic dispersion (CD) and polarization mode dispersion (PMD) severely limit the performance o... more Chromatic dispersion (CD) and polarization mode dispersion (PMD) severely limit the performance of optical transmission systems operating at data rates of 10 Gb/s and beyond. Electrical equalization techniques have been proposed to compensate dispersion in both coherent and intensity modulation/directdetection (IM/DD) systems. The former benefit from the fact that a complete compensation with zero penalty is possible, at least in principle, whereas in the latter the loss of phase information caused by the direct detection process results in a nonzero dispersion penalty even when optimal equalizers are used. In this paper, we investigate the combined adaptive digital equalization of all-order PMD, CD, and laser phase noise in highspeed coherent optical transmission systems. Although electrical equalization in coherent optical transmission systems has been addressed by previous , equalization of the combined effects of CD, PMD, and laser phase noise has not been reported so far. Simultaneous equalization of these impairments is particularly important in modulation systems that exploit polarization to increase the modulation efficiency, such as the joint polarization modulation and M-ary differential phase shift keying (JPMDPSK) system described in [4]. We propose a novel 4-dimensional equalizer structure for JPMDPSK systems. The specific example considered in this paper is 40 Gb/s transmission with a 10 GBaud symbol rate, using DQPSK modulation on each axis of polarization. Our results show that the new fourdimensional equalizer can compensate channel dispersion of up to 1000 km of standard single-mode fiber, with less than 3 dB penalty in signal to noise ratio (SNR). This is a dramatic improvement over 40 Gb/s IM/DD systems, even when they use electrical [5] or optical [6] equalization. The feasibility of the very large scale integration (VLSI) of coherent receivers in current technology is also discussed.
IEEE Global Telecommunications Conference, 2004. GLOBECOM '04., 2004
traditional channel codes designed for transmissions over AWGN channels, in combination with SISO... more traditional channel codes designed for transmissions over AWGN channels, in combination with SISO front-end detectors, achieve asymptotically optimal performance in transmissions over IM/DD optical channels.
2008 IEEE International Conference on Communications, 2008
In this paper we present the architecture and experimental evaluation of a single-chip CMOS maxim... more In this paper we present the architecture and experimental evaluation of a single-chip CMOS maximum-likelihood sequence detection (MLSD) transceiver for electronic dispersion compensation (EDC) of multimode optical fibers (MMF) at 10Gb/s data rate. The primary application of this transceiver is the 10GBASE-LRM standard for 10Gb/s Ethernet over MMF [1]. Application to single-mode fiber (SMF) channels and/or other standards is also possible. Both optical module and line card applications are discussed. The architecture of the receiver is discussed in considerable depth, including implementation details. Extensive experimental results on several channels are presented. For the precursor, postcursor, and symmetric stressors specified by the 10GBASE-LRM standard we demonstrate receiver sensitivities of -14.84dBm, -14.37dBm, and -13.68dBm, respectively, in a line card application with 6 inches of electrical interconnect. These sensitivities exceed the requirements of the standard by 8.34dBo, 7.87dBo, and 7.68dBo 1 , respectively. Measured results on industry defined worst-case fibers and on nonstationary channels such as the dynamic stressor defined by the 10GBASE-LRM standard are also presented.
2011 IEEE Global Telecommunications Conference - GLOBECOM 2011, 2011
This paper introduces a new parallel carrier recovery architecture suitable for ultra-high speed ... more This paper introduces a new parallel carrier recovery architecture suitable for ultra-high speed intradyne coherent optical receivers (e.g., ≥ 40Gb/s). The proposed scheme combines a novel low-latency parallel digital phase locked loop (DPLL) with a feedforward carrier phase recovery (CPR) algorithm. The new low-latency parallel DPLL is designed to compensate not only frequency offset, but also frequency fluctuations such as those induced by mechanical vibrations.
2011 VII Southern Conference on Programmable Logic (SPL), 2011
This paper introduces a new low latency parallel processing digital carrier recovery (CR) archite... more This paper introduces a new low latency parallel processing digital carrier recovery (CR) architecture suitable for ultra-high speed intradyne coherent optical receivers (e.g. ≥ 100Gb/s). The proposed parallel scheme builds upon a novel digital phase locked loop (DPLL) architecture, which breaks the bottleneck of the feedback path. Thus, it is avoided the high latency introduced by the parallel processing implementation in the feedback loop of traditional DPLLs. Numerical results show that the bandwidth and the capture range of the new parallel DPLL are close to those achieved by a serial DPLL. This excellent behavior makes the proposed low latency parallel DPLL architecture an excellent choice for implementing high speed CR systems in both ASIC and FPGA platforms.
2006 IEEE International Conference on Communications, 2006
AbstractWe investigate the performance of maximum likelihood sequence estimation (MLSE) receiver... more AbstractWe investigate the performance of maximum likelihood sequence estimation (MLSE) receiver in the presence of the impairments from both the pulse carver-data modulator timing misalignment (TM) and polarization mode dispersion (PMD) in optically amplified ...
OFC/NFOEC 2008 - 2008 Conference on Optical Fiber Communication/National Fiber Optic Engineers Conference, 2008
We demonstrate that InP modulators together with 1 sample/bit MLSE gives equivalent performance t... more We demonstrate that InP modulators together with 1 sample/bit MLSE gives equivalent performance to linear electro-optic Mach-Zehnder modulators combined with oversampled MLSE, potentially providing significant reduction in power dissipation and footprint.
The Ninth International Conference onCommunications Systems, 2004. ICCS 2004., 2004
We analyze the log-likelihood ratio (LLR) of the received signal yielded by a soft input/soft out... more We analyze the log-likelihood ratio (LLR) of the received signal yielded by a soft input/soft output (SISO) front-end decoder, in intensity modulation direct detection (IM/DD) optical channels operating in the presence of amplified spontaneous emission (ASE) noise. We focus on long haul or metro links spanning several hundred kilometers of single mode fibers with optical amplifiers. Unlike in AWGN channels