Digital signal detection for high speed signaling systems

A method, in a bus receiver to determine a digital signal state in a differential signaling system, said method comprising:

• determining, in the bus receiver, information about a present signal transmission state of differential signals at a current time from a prior digital signal output state, wherein the prior digital signal output state is determined at the time prior to the current time, the information about the present signal transmission state of differential signals of the current time indicating possible transmitted signal levels of the differential signals relative to each other to transmit a digital symbol for the present signal transmission state;
• performing a plurality of comparisons, in the bus receiver, using a first differential input signal of the current time, a second differential input signal of the current time and at least one reference signal based on the information about the present signal transmission state;
• and
• determining a present digital signal output state of the current time from the information about the present signal transmission state and results of the plurality of comparisons.

A method to determine a digital signal state in a high speed signaling system at a bus signal receiver, said method comprising:

• determining, in the bus signal receiver, a previous signal transmission state of differential signals from a prior digital signal output state, wherein the prior digital output state is determined at a time prior to a current time, wherein the signal transmission state of the differential signals indicates signal levels of the differential signals relative to each other to transmit a digital symbol;
• performing, in the bus signal receiver, a comparison between two signals of the current time based on the previous signal transmission state of the differential signals, the two signals being two combinations of at least one received input signal and at least one reference signal, at least one of the two combinations including one of the at least one reference signal;
• and
• determining a present digital signal output state of the current time from the comparison.

A method to reduce crosstalk effect at a bus signal receiver, the method comprising:

• generating a first combined signal, the first combined signal comprising a first differential input signal of a current time and a signal from a neighboring signal line;
• generating a second combined signal, the second combined signal comprising a second differential input signal of the current time;
• comparing, in the bus signal receiver, the first and second combined signals of the current time to determine a present digital signal output state at the current time, wherein the first and second combined signals are compared based on a prior digital signal output state that is determined at the time prior to the current time;
• and
• determining a previous signal transmission state of differential signals based on the prior digital signal output state, wherein the signal transmission state indicates signal levels of the differential signals relative to each other to transmit a digital symbol.

A bus signal receiver for determining a digital signal state in a differential signaling system, said receiver comprising:

• means for comparing a first differential input signal received by the bus signal receiver at a current time to a second differential input signal received by the bus signal receiver at the current time;
• means for determining a prior digital signal output state, wherein the prior digital signal output state is determined at the time prior to the current time;
• means for determining a previous signal transmission state of differential signals from the prior digital signal output state, wherein the signal transmission state of the differential signals indicates a signal level of the first differential input signal relative to the second differential input signal to transmit a digital symbol;
• means for comparing, in the bus signal receiver, said first differential input signal to one of a first reference voltage and a second reference voltage based on the prior digital signal output state;
• means for comparing said second differential input signal to one of said first reference voltage and said second reference voltage;
• and
• means for determining a present digital signal output state of the current time from said means for determining said prior digital signal output state and from all of said means for comparing.

A bus signal receiver to determine a digital signal state in a differential signaling system, said receiver comprising:

• means for determining, in the bus receiver, information about a present signal transmission state of differential signals at a current time from a prior digital signal output state, wherein the prior digital signal output state is determined at the time prior to the current time, the information about the present signal transmission state of differential signals of the current time indicating possible transmitted signal levels of the differential signals relative to each other to transmit a digital symbol for the present signal transmission state;
• means for performing a plurality of comparisons, in the bus receiver, using a first differential input signal of the current time, a second differential input signal of the current time and at least one reference signal based on the information about the present signal transmission state;
• and
• means for determining a present digital signal output state of the current time from the information about the present signal transmission state and results of the plurality of comparisons.

A bus signal receiver to determine a digital signal state in a communication link, said receiver comprising:

• means for determining, in the bus signal receiver, a previous signal transmission state of differential signals from a prior digital signal output state, wherein the prior digital output state is determined at a time prior to a current time, wherein the signal transmission state of the differential signal indicates signal levels of the differential signals relative to each other to transmit a digital symbol;
• means for performing, in the bus signal receiver, a comparison between two signals of the current time based on the previous signal transmission state of the differential signals, the two signals being two combinations of at least one received input signal and at least one reference signal, at least one of the two combinations including one of the at least one reference signal;
• and
• means for determining a present digital signal output state of the current time from the comparison.

A bus signal receiver with reduced crosstalk effect, the bus signal receiver comprising:

• means for generating a first combined signal, the first combined signal comprising a first differential input signal of a current time and a signal from a neighboring signal line;
• means for generating a second combined signal, the second combined signal comprising a second differential input signal of the current time;
• means for comparing, in the bus signal receiver, the first and second combined signals of the current time to determine a present digital signal output state at the current time, wherein the first and second combined signals are compared based on a prior digital signal output state that is determined at the time prior to the current time;
• and
• determining a previous signal transmission state of differential signals based on the prior digital signal output state, wherein the signal transmission state indicates signal levels of the differential signals relative to each other to transmit a digital symbol.

A bus signal receiver for determining a digital signal state in a differential signaling system, said receiver comprising:

• a first amplifier, the first amplifier comparing a first differential input signal received by the bus signal receiver at a current time to a second differential input signal received by the bus signal receiver at the current time;
• a memory device, the memory device storing a plurality of prior digital signal output states, wherein the plurality of prior digital signal output states is determined at the time prior to the current time, the plurality of prior digital signal output states to determine a transmission state of differential signals at the current time, wherein the transmission state of the differential signals indicates a signal level of the first differential input signal relative to the second differential input signal to transmit a digital symbol;
• a second amplifier, the second amplifier comparing said first differential input signal to one of a first reference voltage and a second reference voltage based on the transmission state of the differential signals;
• a third amplifier, the third amplifier comparing said second differential input signal to one of said first reference voltage and said second reference voltage;
• and
• a weighting logic unit coupled with the memory device and all of said amplifiers, the weighting logic determining a present digital signal output state at the current time from said plurality of prior digital signal output states determined at the time prior to the current time and from outputs from all of said amplifiers.

A bus signal receiver to determine a digital signal state in a differential signaling system, said receiver comprising:

• a memory device, the memory device storing at least one prior digital signal output state determined at a time prior to a current time;
• a logic unit coupled with the memory device, the logic unit determining information about a present signal transmission state of differential signals at the current time from the at least one prior digital signal output state, wherein the information about the signal transmission state of differential signals indicates signal levels of the differential signals relative to each other to transmit a digital symbol;
• and
• a plurality of amplifiers coupled with the logic unit, the plurality of amplifiers performing a plurality of comparisons using a first differential input signal of the current time, a second differential input signal of the current time and at least one reference signals based on the information about the present signal transmission state, the logic unit determining a present digital signal output state at the current time from the information about the present signal transmission state and outputs of the plurality of amplifiers.

A bus signal receiver to determine a digital signal state in a communication link, said receiver comprising:

• a memory device, the memory device storing at least one prior digital signal output state determined at a time prior to a current time;
• a logic unit coupled to the memory device, the logic unit determining a previous signal transmission state of differential signals from the at least one prior digital signal output state, wherein the signal transmission state of the differential signals indicates signal levels of the differential signals relative to each other to transmit a digital symbol;
• and
• a signal combining unit coupled with the logic unit, the signal combining unit generating two signals at the current time based on the previous signal transmission state of the differential signals, the two signals are two combinations of at least one received input signal of the current time and at least one reference signal, at least one of the two combinations including one of the at least one reference signal, the logic unit comparing the two combinations to determine a present digital signal output state at the current time.

A bus signal receiver with reduced crosstalk effect, the signal receiver comprising

• a signal combining unit, the signal combining unit generating a first combined signal comprising a first differential input signal of a current time and a signal from a neighboring signal line, the signal combining unit generating a second combined signal comprising a second differential input signal of the current time;
• and
• a comparator coupled to the signal combining unit, the comparator comparing the first and second combined signals to determine a present digital signal output state at the current time, wherein the first and second combined signals are compared based on a prior digital signal output state determined at a time prior to the current time;
• and
• a logic unit coupled to the signal combining unit, the logic unit controlling the signal combining unit, the logic unit to determine a precious signal transmission state of differential signals based on the prior digital signal output state, wherein the signal transmission state indicates signal levels of the differential signals relative to each other to transmit a digital symbol.