Analog receiver equalizer architectures for high-speed wireline and optical applications
The present invention is directed to communication method and techniques. In a specific embodiment, the present invention provides a receiver that interleaves data signal n-ways for n slices. Each of the n slices includes feedforward equalizer and decision feedback equalizers that are coupled to other slices. Each of the n slices also includes an analog-to-digital converter section that includes data and error slicers. There are other embodiments as well.
1. A receiver comprising:
an analog front end (AFE) circuit configured to process data signals received from a communication channel;
a time-interleave (TI) block configured to interleave processed data signals from the AFE circuit n-ways;
an array of n slices comprising a first slice and a second slice, the array of n slices being configured to perform analog-to-digital conversion (ADC) processes and output a digital data stream; and
a digital signal processor (DSP) coupled to the array of n slices and configured to process the digital data stream;
wherein the first slice comprises:
a first feedforward equalizer (FFE) configured to equalize a first interleaved signal from the TI block using one or more precursor values from at least the second slice;
a first decision device coupled to the first FFE and configured to provide a first equalized data stream using one or more postcursor values from at least a third slice; and
a first converter coupled to the first decision device and configured to perform a first ADC process on the first equalized data stream.
2. The receiver of claim 1 wherein the first converter comprises a first data path and a second data path, the first data path comprising data and error slicers, the second data path comprising a sample-and-hold block.
3. The receiver of claim 2 wherein the first converter further comprises a digital-to-analog converter (DAC) coupled to the data and error slicers.
4. The receiver of claim 1 wherein the first slice further comprising a first FFE buffer.
5. The receiver of claim 1 wherein the first slice further comprising a probe slicer.
6. The receiver of claim 1 wherein the first decision device comprises a variable gain amplifier and a decision feedback equalizer (DFE) coupled to at least the second slice.
7. The receiver of claim 1 wherein the first FFE comprises a summer configured to add the one or more precursor values from at least the second slice to one or more post cursor values.
8. The receiver of claim 1 wherein the AFE circuit comprises:
a termination block;
a continuous time linear equalizer; and
a variable gain amplifier.
9. The receiver of claim 1 wherein the DSP is configured to provide reflection cancelation.
10. The receiver of claim 1 wherein the DSP is configured to perform a single-parity forward error correction (SFEC) function.
11. The receiver of claim 1 wherein the DSP is configured to perform an optical interference mitigation (OIM) function.
12. The receiver of claim 1 wherein the second slice comprises:
an equalizer section;
a decision device; and
an optical enhancement section.
13. A signal processing circuit comprising:
a time-interleave (TI) block configured to interleave processed incoming data signals n-ways; and
an array of n slices comprising a first slice and a second slice, the array of n slices being configured to perform analog-to-digital conversion (ADC) processes and output a digital data stream, the first slice comprising:
a first feedforward equalizer (FFE) comprising a first summer and configured to equalize a first interleaved signal from the TI block using one or more precursor values from at least the second slice;
a first decision device comprising a first variable gain amplifier (VGA) coupled to the first FFE and configured to provide a first equalized data stream using one or more postcursor values from at least a third slice; and
a first converter comprising a first plurality of slicers and configured to perform a first ADC process on the first equalized data stream.
14. The signal processing circuit of claim 13 wherein the first plurality of slicers comprises a first probe slicer.
15. The signal processing circuit of claim 13 wherein the first decision device comprises a second summer coupled to a fourth slice.
16. The signal processing circuit of claim 13 wherein the first plurality of slicers comprises data slicers and error slicers.
17. The signal processing circuit of claim 13 wherein the first converter comprises a first path and a second path, the first path comprising the first plurality of slicers and the second path comprising a hold buffer.
18. The signal processing circuit of claim 13 wherein:
n is 16; and
the incoming data signals are associated with a PAM-4 protocol.