摘要:
A transimpedance amplifier (TIA) circuit usable for burst mode communications is provided. The TIA circuit includes a TIA stage, a limiter-amplifier, and a DC restoration loop. The invention overcomes problems of the prior art relating to burst communications, such as a DC level in the output signal which can change from burst to burst and a duty-cycle distortion in large signals. This is achieved by using a DC restoration loop that ensures achieving zero DC potential within variable acquisition periods.
摘要:
A circuit for detecting optical failures in a passive optical network (PON) wherein digital burst data transmitted by an optical transmitter is monitored by a photodiode, includes a power determination unit coupled to the photodiode for providing measurements of an output optical power of a high logic level and a low logic level of the digital burst data during ON times of the optical transmitter and for providing a measurement of an output optical power during OFF times of the optical transmitter. A logic unit coupled to the power determination unit is responsive to the measurements for generating control and calibration signals. Such a circuit may be used for detecting rogue optical network unit (ONU) failure or eye safety hazards in a passive optical network (PON) wherein digital burst data transmitted by an optical transmitter is monitored by a photodiode.
摘要:
Burst mode clock and data recovery (BCDR) circuit and method capable of fast data recovery of passive optical network (PON) traffic. An over-sampled data stream is generated from an input burst data signal and a phase interpolator generates sampling clock signals using a reference clock and phase information. A phase estimation unit (PEU) determines a phase error in the over-sampled data streams; and a phase retrieval unit sets the phase interpolator with the respective phase information of the input burst data signal prior to reception of the input burst data signal.
摘要:
A transimpedance amplifier (TIA) circuit usable for burst mode communications is provided. The TIA circuit includes a TIA stage, a limiter-amplifier, and a DC restoration loop. The invention overcomes problems of the prior art relating to burst communications, such as a DC level in the output signal which can change from burst to burst and a duty-cycle distortion in large signals. This is achieved by using a DC restoration loop that ensures achieving zero DC potential within variable acquisition periods.
摘要:
This invention discloses an apparatus for electrical testing of an electrical circuit (12) having first and second side surfaces and including a plurality of conductors, the apparatus including at least one stimulation electrode (14, 16, 20) disposed adjacent at least one of the first and second side surfaces of the electrical circuit and being operative to apply thereto a stimulation electromagnetic field in a non-contact manner, at least one sensing electrode (25) disposed adjacent at least one of the first and second side surfaces of the electrical circuit and being operative to sense a resulting electromagnetic field produced by application of the stimulation electromagnetic field at various locations thereon in a non-contact manner wherein at least one of the at least one stimulation electrode and the at least one sensing electrode includes at least two electrodes at least one of which is disposed adjacent each of the first and second side surfaces of the electrical circuit. A method for electrical testing of an electrical circuit having first and second side surfaces and including a plurality of conductors is also disclosed.
摘要:
Apparatus and method to measure the quality of burst signals and to perform optical line diagnostics in and optical passive optical network (PON). Statistical information about phase noise (jitter), signal distortion, clock distortions, and any other effects present in burst signals is generated. The statistics are based on phase and bit-length distortions, direction and length of the effect as detected by a phase error detector integrated in a burst mode clock and data recovery (BCDR) circuit. The invention can be further adapted to perform optical line diagnostics to detect the root cause performance degradation and failures in the PON, thereby providing an optical layer supervision tool for monitoring the PON. The statistical information can be used to estimate the quality of service (QoS) per customer connected to the PON. In addition, the generated statistic information can be used to calibrate transmission parameters of optical network unit (ONU) transmitters.
摘要:
Apparatus and method to measure the quality of burst signals and to perform optical line diagnostics in and optical passive optical network (PON). Statistical information about phase noise (jitter), signal distortion, clock distortions, and any other effects present in burst signals is generated. The statistics are based oil phase and bit-length distortions, direction and length of the effect as detected by a phase error detector integrated in a burst mode clock and data recovery (BCDR) circuit. The invention can be further adapted to perform optical line diagnostics to detect the root cause performance degradation and failures in the PON, thereby providing an optical layer supervision tool for monitoring the PON. The statistical information can be used to estimate the quality of service (QoS) per customer connected to the PON. In addition, the generated statistic information can be used to calibrate transmission parameters of optical network unit (ONU) transmitters.
摘要:
Apparatus for the electrical testing of electrical circuits including at least one array of non-contact stimulator electrodes having a multiplicity of individually controlled stimulator electrodes arranged to be linearly disposed adjacent a first side of an electrical circuit to be tested; a signal generator coupled to the at least one array arranged to supply an electrical stimulation signal to each of the stimulator electrodes; and at least two non-contact sensor electrodes, each having dimensions sufficiently large to overlay part of a conductor on the electrical circuit to be tested.
摘要:
Burst mode clock and data recovery (BCDR) circuit and method capable of fast data recovery of passive optical network (PON) traffic. An over-sampled data stream is generated from an input burst data signal and a phase interpolator generates sampling clock signals using a reference clock and phase information. A phase estimation unit (PEU) determines a phase error in the over-sampled data streams; and a phase retrieval unit sets the phase interpolator with the respective phase information of the input burst data signal prior to reception of the input burst data signal.
摘要:
Burst mode clock and data recovery (BCDR) circuit and method capable of fast data recovery of passive optical network (PON) traffic. An over-sampled data stream is generated from an input burst data signal and a phase interpolator generates sampling clock signals using a reference clock and phase information. A phase estimation unit (PEU) determines a phase error in the over-sampled data streams; and a phase retrieval unit sets the phase interpolator with the respective phase information of the input burst data signal prior to reception of the input burst data signal.