摘要:
Certain aspects for the start-up procedure of transceivers supporting higher data rates over twisted-pair copper cabling are provided for 10 Gbit/sec Ethernet links (10GBASE-T). During a PMA (physical medium attachment) training period of the start-up procedure, long PMA training frames are exchanged periodically between link partners. A significant portion of each PMA training frame consists of known pseudo random sequences simultaneously transmitted over four wire pairs. PMA training frames include an InfoField for exchanging parameters and control information between link partners. For example, the InfoField's payload comprises fields for indicating current transmit power backoff (PBO), next PBO, requested PBO, transition count, control information, and for communicating precoder coefficients. Information in InfoFields is repeated and is not necessary that a link partner decodes every InfoField. For example, by occasionally reading the transition count, a link partner can determine when a change in transmit PBO and/or a state transition is to occur.
摘要:
Certain aspects for the start-up procedure of transceivers supporting higher data rates over twisted-pair copper cabling are provided for 10 Gbit/sec Ethernet links (10GBASE-T). During a PMA (physical medium attachment) training period of the start-up procedure, long PMA training frames are exchanged periodically between link partners. A significant portion of each PMA training frame consists of known pseudo random sequences simultaneously transmitted over four wire pairs. PMA training frames include an InfoField for exchanging parameters and control information between link partners. For example, the InfoField's payload comprises fields for indicating current transmit power backoff (PBO), next PBO, requested PBO, transition count, control information, and for communicating precoder coefficients. Information in InfoFields is repeated and is not necessary that a link partner decodes every InfoField. For example, by occasionally reading the transition count, a link partner can determine when a change in transmit PBO and/or a state transition is to occur.
摘要:
Certain aspects for the start-up procedure of transceivers supporting higher data rates over twisted-pair copper cabling are provided for 10 Gbit/sec Ethernet links (10GBASE-T). During a PMA (physical medium attachment) training period of the start-up procedure, long PMA training frames are exchanged periodically between link partners. A significant portion of each PMA training frame consists of known pseudo random sequences simultaneously transmitted over four wire pairs. PMA training frames include an InfoField for exchanging parameters and control information between link partners. For example, the InfoField's payload comprises fields for indicating current transmit power backoff (PBO), next PBO, requested PBO, transition count, control information, and for communicating precoder coefficients. Information in InfoFields is repeated and is not necessary that a link partner decodes every InfoField. For example, by occasionally reading the transition count, a link partner can determine when a change in transmit PBO and/or a state transition is to occur.
摘要:
A two-stage block synchronization and scrambling module includes a synchronization PRNG module, a scramble PRNG module, a summing module, and a storage module. The synchronization PRNG module is clocked once per N+1 bit PCS frame (N arbitrary) to produce a synchronization bit and a pseudo-random starting state for the scramble PRNG. The scramble PRNG module is clocked N times per PCS frame to produce a cipher stream starting with a pseudo-random state from the synchronization PRNG. The summing module is operably coupled to sum the cipher stream and a PCS frame payload to produce scrambled payload. The storage module is operably coupled to store the scrambled payload with the synchronization bit. Synchronization bits from successive frames are a running bit-serial representation of the synchronization PRNG state and are used by the receiver to synchronize with the transmit scrambler.
摘要:
LDPC (Low Density Parity Check) coded 128 DSQ (Double Square QAM) constellation modulation and its associated labeling. A novel means is introduced by which a constellation may be arranged and mapping in its symbols may be determined to provide for improved performance. One application area in which this may be employed is transmission over twisted pair (typically copper) cabling existent within data centers of various networks. The operation of the IEEE 802.3 Ethernet local area networks currently being used (as well as those currently under development) would benefit greatly by employing the various principles presented herein. When this novel approach of an LDPC coded 128 DSQ constellation modulation combined with TH (Tomlinson-Harashima) preceding is employed within a communication device at a transmitter end of a communication channel (i.e., in a transmitter and/or a transceiver), the overall operation of a communication system may improve significantly when compared to prior techniques.
摘要:
Certain aspects for the start-up procedure of transceivers supporting higher data rates over twisted-pair copper cabling are provided for 10 Gbit/sec Ethernet links (10GBASE-T). During a PMA (physical medium attachment) training period of the start-up procedure, long PMA training frames are exchanged periodically between link partners. A significant portion of each PMA training frame consists of known pseudo random sequences simultaneously transmitted over four wire pairs. PMA training frames include an InfoField for exchanging parameters and control information between link partners. For example, the InfoField's payload comprises fields for indicating current transmit power backoff (PBO), next PBO, requested PBO, transition count, control information, and for communicating precoder coefficients. Information in InfoFields is repeated and is not necessary that a link partner decodes every InfoField. For example, by occasionally reading the transition count, a link partner can determine when a change in transmit PBO and/or a state transition is to occur.
摘要:
A method, system and computer program product to adjust transfer rates on conductors in a multi-conductor cable comprising monitoring signals received on each conductor, determining a Signal to Noise Ratio (SNR) for each conductor and adjusting a transfer rate on one or more conductors based on the corresponding SNR. In an embodiment the multi-conductor cable is a twisted pair Ethernet cable. The method further comprises determining whether a conductor is transmitting at an optimal transfer rate as a function of its SNR, calculating an optimal transfer rate for each conductor as a function of its SNR and periodically measuring a change in SNR on each conductor. If the change in SNR is greater than a predetermined threshold, then the transfer rate is re-calculated for the conductors requiring transfer rate adjustment as a function of SNR.
摘要:
Camera heads configured to provide digitally articulated images or video, at adjustable resolutions and/or offsets and orientations, to a camera control unit (CCU) or other electronic computing system for display, storage, and/or transmission to other systems are disclosed.
摘要:
Typical transceivers have multiple near-end and multiple far-end crosstalk cancellation filters. Crosstalk cancellation is one of the largest contributors to power dissipation in the DSP portion of high speed Ethernet transceivers. By detecting the cable type, a transceiver could automatically turn off its crosstalk cancellation filters when driving shielded twisted pair (STP) cables and substantially reduce the overall power dissipation in this configuration. Adaptive digital crosstalk cancellers automatically adjust the coefficients of a digital filter to match the coupling function between two channels. The impulse response of an optimal crosstalk cancellation filter can be used to determine a metric indicating the amount of coupling between the two channels. STP cables will have a much lower amount of coupling between wire-pairs than unshielded twisted pair cables.
摘要:
Communication devices coupled via a communication link may comprise physical layer devices that may be operable to determine presence of a received signal and to mitigate noise in the signal prior to processing and/or validating the signal. Analog and/or digital signal processing may be utilized to process the signal and/or mitigate noise in the signal. Noise mitigation may comprise near-end crosstalk cancelling and/or echo cancelling and/or may utilize local transmit signal information. Subsequent to noise mitigation, samples of the noise reduced signal may be accumulated and/or an average signal strength and/or average signal power level may be determined. The average signal strength and/or average signal power level may be compared to one or more thresholds which may be configurable and/or programmable.