A multi-PAM equalizer receives an input signal distorted by inter-symbol interference (ISI) and expressing a series of symbols each representing one of four pulse amplitudes to convey two binary bits of data per symbol. High-order circuitry resolves the most-significant bit (MSB) of each two-bit symbol, whereas low-order circuitry 115 resolves the immediate least-significant bit (LSB). The MSB is used without the LSB for timing recovery and to calculate tap values for both MSB and LSB evaluation.

A signal analysis method is described. The signal analysis method comprises: receiving an N-ary input signal, the input signal comprising a symbol sequence; determining at least two threshold transition times of the input signal within a predetermined time period, wherein the input signal respectively crosses an amplitude threshold of several predetermined amplitude thresholds at each of the threshold transition times; determining time intervals between the threshold transition times; evaluating the time intervals based on a set of predefined conditions; and assigning the threshold transition times to at least one symbol transition based on the evaluation. Further, a signal analysis module is described.

A receiver device implements enhanced data reception with edge-based clock and data recovery such as with a flash analog-to-digital converter architecture. In an example embodiment, the device implements a first phase adjustment control loop, with for example, a bang-bang phase detector, that detects data transitions for adjusting sampling at an optimal edge time with an edge sampler by adjusting a phase of an edge clock of the sampler. This loop may further adjust sampling in received data intervals for optimal data reception by adjusting the phase of a data clock of a data sampler such a flash ADC. The device may also implement a second phase adjustment control loop with, for example, a baud-rate phase detector, that detects data intervals for further adjusting sampling at an optimal data time with the data sampler.

A sensor may determine a sampling pattern based on a group of synchronization signals received by the sensor. The sampling pattern may identify an expected time for receiving an upcoming synchronization signal. The sensor may trigger, based on the sampling pattern, a performance of a sensor operation associated with the upcoming synchronization signal. The performance of the sensor operation may be triggered before the upcoming synchronization signal is received.

A system and method for data sampler drift compensation in a SerDes receiver. Off-data values are received at a drift compensation engine from a plurality of data value selectors coupled to one of a plurality of data sampler pairs of a speculative Decision Feedback Equalizer (DFE) of a SerDes receiver. A drift compensation value for each of the data samplers is generated by the drift compensation engine based upon the off-data values received from each of the plurality of data value selectors and, a sampling level of each of the data samplers of the plurality of data sampler pairs of the DFE is adjusted based upon the drift compensation value from the drift compensation engine.

According to one aspect of the invention, there is provided a signal processing method, wherein a frame is generated in which at least one position of occurrence of a transition in a pulse value is determined from an input bitstream. According to another aspect of the invention, there is provided a signal processing method, wherein a frame including at least one pulse having a pulse width not less than a minimum pulse width is generated from an input bitstream.

Embodiments of this application disclose a phase detection method, a phase detection circuit, and a clock recovery apparatus. The method includes: receiving a first signal, and deciding a (2M1) level of the first signal to obtain a decision result, where the first signal is a (2M1)-level signal, and M is a positive integer: obtaining a response amplitude parameter of a transmission channel; extracting clock phase information in the first signal based on the first signal, the decision result, and the response amplitude parameter; and determining output clock phase information based on at least three decision results and at least three pieces of clock phase information in at least three symbol periods. According to the foregoing method, a stable phase detection gain can be achieved when a clock phase is tuned to a pulse response edge

A signal analysis method is described. The signal analysis method includes the following steps. A first difference quantity is determined based on a first set of samples by a first polyphase filter, wherein the first set of samples includes at least two input samples. A second difference quantity is determined based on a second set of samples by a second polyphase filter, wherein the second set of samples includes at least two input samples, wherein the input samples associated with the second set of samples are time-shifted with respect to the input samples associated with the first set of samples. The first difference quantity and the second difference quantity are compared based on a predefined criterion. At least one timing parameter of the symbol sequence is determined based on the comparison of the first difference quantity and the second difference quantity. Further, a signal processing module is described.

A clock data recovery circuit includes a circuit that receives a data signal for which each of a plurality of potential levels is associated with a value of 2 bits or more, based on a result of a first comparison that compares the 3 or more first thresholds with the data signal at timing synchronized with a clock signal; a circuit that outputs a result of a second comparison that compares the data signal with a second threshold at the timing; a circuit that generates a phase difference signal indicating whether to advance or delay a phase of the clock signal, based on the result of the determination and the result of the second comparison; a filter that generates a phase adjusted value indicating an adjustment amount of the phase, based on the phase difference signal; and a circuit that adjusts the phase based on the phase adjusted value.

A signal analysis method for recovering a clock signal from an input signal is described. The input signal comprises a symbol sequence, wherein each symbol has one of N different amplitude values, and wherein N is an integer bigger than 1. The signal analysis method comprises the following steps: The input signal is received. Transition times of the input signal are determined, wherein the input signal respectively crosses one of several predetermined amplitude thresholds at the transition times. The transition times are transformed into one reference symbol period, thereby obtaining transformed transition times. The clock signal is determined based on the transformed transition times. Further, a signal analysis module for recovering a clock signal from an input signal is described.