ali ghiasi - Academia.edu (original) (raw)
Related Authors
University of the Basque Country, Euskal Herriko Unibertsitatea
UERJ - Universidade do Estado do Rio de Janeiro / Rio de Janeiro State University
Uploads
Papers by ali ghiasi
A semiconductor laser diode with a nominal relaxation oscillation frequency of 6 GHz with an anti... more A semiconductor laser diode with a nominal relaxation oscillation frequency of 6 GHz with an anti-reflection coating on one facet is coupled to an external high Q cavity with the fundamental resonance set to 5 GHz. The laser diode is mounted in a custom microstrip fixture and is driven by a HP-851OA network analyzer. The experimental and theoretical results show enhancement greater than 25 dB at the external cavity resonance frequencies. The results also show holes near the resonance frequencies which may affect the useful bandwidth.
The goal is the modulation of lasers above the -3dB modulation bandwidth. The approach is to coat... more The goal is the modulation of lasers above the -3dB modulation bandwidth. The approach is to coat one laser facet with an anti-reflection coating and form an external cavity. The external cavity laser was built and characterized theoretically. An impedance-matching microstrip was designed and measured. An 8 GHz oscillator was built using a 0.3 micron MESFET. It was found that the optical feedback increases the light modulation depth by 25 dB on the first harmonic and 34dB on the second harmonic in external cavity laser diodes. The model, which has proven accurate thus far, indicates that diode parasitics make it preferable to use the second harmonic generated by a 30 GHz cavity, rather than the first harmonic from a 60 GHz cavity.
This paper describes a lowloss microstrip matching circuit with large bandwidth for connecting an... more This paper describes a lowloss microstrip matching circuit with large bandwidth for connecting an Ortel SL1010 laser diode of nominal impedance of 2 ohms, together with parasitics, to a 50 ohm microstrip line. This technique utilizes a microstrip Chebychev transformer without very wide line widths, to obtain the match at a center frequency of 10.5 Ghz with bandwidth of 9 Ghz, insertion loss of less than 1.5 dB and reflection coefficient of better than -10 dB.
This technical report defines the functions and electrical characteristics of the high-speed para... more This technical report defines the functions and electrical characteristics of the high-speed parallel interface between the physical (FC-0) layer and the transmission protocol (FC-1) layer of a Fibre Channel port. This interface operates at either 2125,0 or 1062,5 Mbaud. This interface has additional functions and different electrical characteristics compared to the "Fibre Channel -10-bit Interface", previously published as X3. TR-18:1997, which operated at 1062,5 MBaud only. This document applies in full to systems where the FC-0 and FC-1 layer are implemented as separate devices. For systems where the FC-0 and FC-1 devices are integrated, only the functional characteristics of this document apply.
A semiconductor laser diode with a nominal relaxation oscillation frequency of 6 GHz with an anti... more A semiconductor laser diode with a nominal relaxation oscillation frequency of 6 GHz with an anti-reflection coating on one facet is coupled to an external high Q cavity with the fundamental resonance set to 5 GHz. The laser diode is mounted in a custom microstrip fixture and is driven by a HP-851OA network analyzer. The experimental and theoretical results show enhancement greater than 25 dB at the external cavity resonance frequencies. The results also show holes near the resonance frequencies which may affect the useful bandwidth.
The goal is the modulation of lasers above the -3dB modulation bandwidth. The approach is to coat... more The goal is the modulation of lasers above the -3dB modulation bandwidth. The approach is to coat one laser facet with an anti-reflection coating and form an external cavity. The external cavity laser was built and characterized theoretically. An impedance-matching microstrip was designed and measured. An 8 GHz oscillator was built using a 0.3 micron MESFET. It was found that the optical feedback increases the light modulation depth by 25 dB on the first harmonic and 34dB on the second harmonic in external cavity laser diodes. The model, which has proven accurate thus far, indicates that diode parasitics make it preferable to use the second harmonic generated by a 30 GHz cavity, rather than the first harmonic from a 60 GHz cavity.
This paper describes a lowloss microstrip matching circuit with large bandwidth for connecting an... more This paper describes a lowloss microstrip matching circuit with large bandwidth for connecting an Ortel SL1010 laser diode of nominal impedance of 2 ohms, together with parasitics, to a 50 ohm microstrip line. This technique utilizes a microstrip Chebychev transformer without very wide line widths, to obtain the match at a center frequency of 10.5 Ghz with bandwidth of 9 Ghz, insertion loss of less than 1.5 dB and reflection coefficient of better than -10 dB.
This technical report defines the functions and electrical characteristics of the high-speed para... more This technical report defines the functions and electrical characteristics of the high-speed parallel interface between the physical (FC-0) layer and the transmission protocol (FC-1) layer of a Fibre Channel port. This interface operates at either 2125,0 or 1062,5 Mbaud. This interface has additional functions and different electrical characteristics compared to the "Fibre Channel -10-bit Interface", previously published as X3. TR-18:1997, which operated at 1062,5 MBaud only. This document applies in full to systems where the FC-0 and FC-1 layer are implemented as separate devices. For systems where the FC-0 and FC-1 devices are integrated, only the functional characteristics of this document apply.