Methods and systems for DSP-based receivers
First Claim
1. A method for receiving data signals, comprising the steps of:
- (1) receiving a data signal having a symbol rate;
(2) generating N sampling signals having a first frequency that is lower than said symbol rate, said N sampling signals shifted in phase relative to one another;
(3) controlling N analog-to-digital converter (“
ADC”
) paths with said N sampling signals to sample said data signal at said phases;
(4) individually adjusting one or more parameters for each of said N ADC paths; and
(5) generating a digital signal representative of said received data signal from samples received from said N ADC paths.
7 Assignments
0 Petitions
Accused Products
Abstract
Digital signal processing based methods and systems for receiving data signals include parallel receivers, multi-channel receivers, timing recovery schemes, and, without limitation, equalization schemes. The present invention is implemented as a multi-path parallel receiver in which an analog-to-digital converter (“ADC”) and/or a digital signal processor (“DSP”) are implemented with parallel paths that operate at lower rates than the received data signal. In an embodiment, a parallel DSP-based receiver in accordance with the invention includes a separate timing recovery loop for each ADC path. The separate timing recovery loops can be used to compensate for timing phase errors in the clock generation circuit that are different for each path. In an embodiment, a parallel DSP-based receiver includes a separate automatic gain control (AGC) loop for each ADC path. The separate AGC loops can be used to compensate for gain errors on a path-by-path basis. In an embodiment, a parallel DSP-based receiver includes a separate offset compensation loop for each ADC path. The separate offset compensation loops can be used to independently compensate for offsets that are different for each path. In an embodiment the present invention is implemented as a multi-channel receiver that receives a plurality of data signals. In an embodiment, one or more of the following types of equalization are performed, alone and/or in various combinations with one another: Viterbi equalization; feed-forward equalization (“FFE”); and/or decision feed-back equalization (“DFE”).
-
Citations
66 Claims
-
1. A method for receiving data signals, comprising the steps of:
-
(1) receiving a data signal having a symbol rate;
(2) generating N sampling signals having a first frequency that is lower than said symbol rate, said N sampling signals shifted in phase relative to one another;
(3) controlling N analog-to-digital converter (“
ADC”
) paths with said N sampling signals to sample said data signal at said phases;
(4) individually adjusting one or more parameters for each of said N ADC paths; and
(5) generating a digital signal representative of said received data signal from samples received from said N ADC paths. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60)
-
-
17. A receiver, comprising:
-
a receiver input;
an analog-to-digital converter (“
ADC”
) array of N ADC paths, wherein N is an integer greater than 1, each said ADC path including an ADC path input coupled to said receiver input;
an M-path DSP coupled to said ADC array, wherein M=kN and k is an integer or a number in the form of Us, where s is an integer;
said M-path DSP having a timing recovery module, wherein said timing recovery module recovers N sampling clocks from a data signal received at said receiver input, said data signal having a baud frequency, said N sampling clocks having a first frequency that is N times lower than said baud frequency, said N sampling clocks being shifted in phase relative to one another, whereby said timing recovery module provides said N sampling clocks to said N ADC paths, whereby said N sampling clocks control said N ADC paths to sample said received signal at said phases; and
means for individually adjusting one or more parameters for each of said N ADC paths.
-
-
61. A method for receiving data signals, comprising the steps of:
-
(1) receiving a data signal having a symbol rate;
(2) generating N sampling signals having a first frequency that is lower than said symbol rate, said N sampling signals shifted in phase relative to one another;
(3) controlling N analog-to-digital converter (“
ADC”
) paths with said N sampling signals to sample said data signal at said phases;
(4) performing one or more digital processes on samples from said N ADC paths and generating control signals from said one or more digital processes;
(5) individually adjusting one or more parameters for each of said N ADC paths using said control signals; and
(6) generating a digital signal representative of said received data signal.
-
-
62. A method for receiving data signals, comprising the steps of:
-
(1) receiving a data signal having a symbol rate;
(2) generating N sampling signals having a first frequency that is lower than said symbol rate, said N sampling signals shifted in phase relative to one another;
(3) controlling N analog-to-digital converter (“
ADC”
) paths with said N sampling signals to sample said data signal at said phases;
(4) performing one or more M-path parallel digital processes on samples from said N ADC paths, wherein M=kN, and k is an integer or a number in the form of 1/s, where s is an integer, and generating control signals from said one or more M-path parallel digital processes;
(5) individually adjusting one or more parameters for each of said N ADC paths using said control signals; and
(6) generating a digital signal representative of said received data signal.
-
-
63. A method for receiving data signals, comprising the steps of:
-
(1) receiving a data signal having a symbol rate;
(2) generating N sampling signals having a first frequency that is lower than said symbol rate, said N sampling signals shifted in phase relative to one another;
(3) controlling N analog-to-digital converter (“
ADC”
) paths with said N sampling signals to sample said data signal at said phases;
(4) individually adjusting one or more parameters for each of said N ADC paths, including individually adjusting at least a sampling phase in each of said N ADC paths to compensate for phase errors between each said N sampling signals and said received data signal; and
(5) generating a digital signal representative of said received data signal from samples received from said N ADC paths.
-
-
64. A receiver, comprising:
-
a receiver input;
an analog-to-digital converter (“
ADC”
) array of N ADC paths, wherein N is an integer greater than 1, each said ADC path including an ADC path input coupled to said receiver input;
an M-path DSP coupled to said ADC array, wherein M=kN and k is an integer or a number in the form of 1/s, where s is an integer; and
said M-path DSP having a timing recovery module, wherein said timing recovery module recovers N sampling clocks from a data signal received at said receiver input, said data signal having a baud frequency, said N sampling clocks having a first frequency that is N times lower than said baud frequency, said N sampling clocks being shifted in phase relative to one another, whereby said timing recovery module provides said N sampling clocks to said N ADC paths, whereby said N sampling clocks control said N ADC paths to sample said received signal at said phases.
-
-
65. A method for receiving data signals, comprising the steps of:
-
(1) receiving a data signal having a symbol rate;
(2) generating N sampling signals having a first frequency that is lower than said symbol rate, said N sampling signals shifted in phase relative to one another;
(3) controlling N analog-to-digital converter (“
ADC”
) paths with said N sampling signals to sample said data signal at said phases;
(4) performing one or more digital processes on samples from said N ADC paths and generating control signals from said one or more digital processes;
(5) individually adjusting one or more parameters for each of said N ADC paths using said control signals, including individually adjusting at least a sampling phase in each of said N ADC paths to compensate for phase errors between each said N sampling signals and said received data signal; and
(6) generating a digital signal representative of said received data signal.
-
-
66. A method for receiving data signals, comprising the steps of:
-
(1) receiving a data signal having a symbol rate;
(2) generating N sampling signals having a first frequency that is lower than said symbol rate, said N sampling signals shifted in phase relative to one another;
(3) controlling N analog-to-digital converter (“
ADC”
) paths with said N sampling signals to sample said data signal at said phases;
(4) performing one or more M-path parallel digital processes on samples from said N ADC paths, wherein M=kN, and k is an integer or a number in the form of 1/s, where s is an integer, and generating control signals from said one or more M-path parallel digital processes;
(5) individually adjusting one or more parameters for each of said N ADC paths using said control signals, including individually adjusting at least a sampling phase in each of said N ADC paths to compensate for phase errors between each said N sampling signals and said received data signal; and
(6) generating a digital signal representative of said received data signal.
-
Specification