System and method of frame alignment at a receiver with power optimization mechanisms. A framer is configured to perform a frame alignment process on a data stream and enter an inactive state after frame alignment is achieved. In the inactive state, the circuits used to perform the frame alignment process in the framer can be powered down or otherwise placed in a power reduction mode. Responsive to an indication that data processing at the receiver becomes out-of-frame again, the framer can wake up from the inactive state and restart the frame alignment process. An out-of-frame indication may be generated by error detection logic (e.g., forward error correction (FEC) decoder) when it detects an excessive number of uncorrectable errors.

System and method of frame alignment at a receiver with power optimization mechanisms. A framer uses one or more comparators to search for the FAW in the incoming data, with each comparator configured to serially compare multiple windows of a parallel M-bit block (as provided from a parallel data bus) with the FAW. Multiple comparators in the framer may operate in parallel to search for the FAW at different windows. This configuration can significantly reduce the comparator count and so the gate count as well as the chip area in a framer. Power consumption can be advantageously reduced as one comparator operating serially consumes less power than multiple comparators in parallel because less gate toggling is involved.

A clock data recovery circuit configured to generate frequency step that is uniform regardless of operational conditions of the clock data recovery circuit.

Techniques and apparatus for detection of a signal at an I/O interface module are described. In one embodiment, for example, an apparatus to provide signal detection may include at least one receiver, at least one memory, and logic for a signal detection module, at least a portion of the logic comprised in hardware coupled to the at least one memory and the at least one receiver, the logic to access a plurality of pulse signals of a clock and data recovery (CDR) circuit, analyze at least one pulse characteristic of the plurality of pulse signals, and generate a signal determination to indicate a signal at the at least one receiver based on the at least one pulse characteristic. Other embodiments are described and claimed.

A serial input/output method and receiver include an receiver portion to receive an analog differential serial input and sample the input to provide data and error signals, an equalization feedback loop responsive to the data and error signals to adjust the receiver portion, a phase feedback mechanism separate from the equalization feedback loop to provide a phase error, and a clock data recovery block coupled to receive the phase error to perform timing recovery for the receiver portion independent of the equalization feedback to adjust the sampling.

A data reception device includes: an equalizer circuit that shapes a waveform of an input signal according to a set gain value; a CDR circuit which recovers a plurality of clock signals having different phases in one cycle from the input signal after being subjected to the waveform shaping performed by the equalizer circuit; an oversampler which performs sampling of the waveform-shaped input signal in synchronization with the plurality of clock signals and recovers a plurality of input data from the waveform-shaped input signal; and a calibration control unit which determines whether the oversampler correctly recovers the input data based on a result of the sampling performed by the oversampler, and generates a control signal to set the gain value of the equalizer circuit based on a determination result when it is determined that the input data is not correctly recovered.

Embodiments of circuits for use with an amplifier that includes multiple amplifier paths include a first circuit and a second circuit in parallel with the first circuit. The first circuit includes a first input coupled to a first power divider output, a first output coupled to a first amplifier path of the multiple amplifier paths, and a first adjustable phase shifter and a first attenuator series coupled between the first input and the first output. The second circuit includes a second input coupled to a second power divider output, a second output coupled to a second amplifier path of the multiple amplifier paths, and a second adjustable phase shifter coupled between the second input and the second output.

A receiver for processing a data stream includes: a bursty phase detector having a first voltage-controlled oscillator configured to provide a first VCO phase, a signal stream detector configured to provide a data stream phase and a data stream detect signal, and a delay component configured to receive the data stream; a clocking circuit coupled to receive an output of the delay component, the data stream phase, and the data stream detect signal, the clocking circuit configured to provide a second VCO phase at an output of the clocking circuit, wherein the clocking circuit is configured to operate based on a fractional relationship between a reference clock frequency and an output frequency; and a data sample selector with a first input coupled to the output of the delay component, and a second input coupled to the output of the clocking circuit.

This invention relates to timing message selection techniques that can be used in conjunction with a clock recovery mechanism to mitigate the effects of packet delay variation on timing messages exchanged over a packet network, particularly when seeking to synchronize the time of a clock in a slave device to that of a master clock. The selection techniques allow the identification of optimal or minimally-delayed timing messages which can subsequently be used in timing synchronisation. Embodiments of the invention provide techniques which identify optimal timing messages in both forward and reverse directions which are then processed to form composite timing messages which are used in a frequency estimation algorithm. Timing messages selected by the methods of the invention are particularly useful in phase synchronization between the master and slave clocks.

Certain aspects of the present disclosure provide techniques for signaling information regarding beams used for data and control transmissions to a UE. For example, a method for wireless communications by a user equipment (UE), may generally include signaling information to a base station (BS) that the UE is seeking recovery of a beamformed link between the BS and the UE, and participating in recovery of the beamformed link in accordance with the information. A method for wireless communications by a base station (BS), may generally include receiving information from a user equipment (UE) that the UE is seeking recovery of a beamformed link between the BS and the UE, and participating in recovery of the beamformed link in accordance with the information.