Receiver system having analog pre-filter and digital equalizer

A receiver system comprising:

• an analog pre-filter comprising analog filtering circuitry that operates according to a transfer function (1−Vc)+VcPF(s) for analog filtering a symbol-information-carrying input analog signal, or a first intermediate analog signal generated from the input analog signal, to produce a filtered analog signal with reduced intersymbol interference where Vc is a variable that varies adaptively between 0 and 1, PF(s) is an analog filter transfer function, and s is a frequency-transform variable;
• an analog-to-digital converter for converting the filtered analog signal, or a second intermediate analog signal generated from the filtered analog signal, into an initial digital signal;
• an equalizer for equalizing the initial digital signal, or an intermediate digital signal generated from the initial digital signal, to produce an equalized digital signal as a stream of equalized digital values;
• and
• a decoder for converting the equalized digital values, or intermediate digital values generated from the equalized digital values, into a stream of symbols.

A receiver system comprising:

• an analog pre-filter for analog filtering a symbol-information-carrying input analog signal, or a first intermediate analog signal generated from the input analog signal, to produce a filtered analog signal, the pre-filter comprising a plurality of analog filters arranged in cascade, each analog filter operating according to a transfer function (1−Vci)+VciPFi(s) where i is a running integer that identifies each different one of the analog filters, Vci is a variable that varies adaptively between 0 and 1 for the ith analog filter, PFi(s) is an analog filter transfer function for the ith analog filter, and s is a frequency-transform variable;
• an analog-to-digital converter for converting the filtered analog signal, or a second intermediate analog signal generated from the filtered analog signal, into an initial digital signal;
• an equalizer for equalizing the initial digital signal, or an intermediate digital signal generated from the initial digital signal, to produce an equalized digital signal as a stream of equalized digital values;
• and
• a decoder for converting the equalized digital values, or intermediate digital values generated from the equalized digital values, into a stream of symbols.

A method comprising:

• analog filtering a symbol-information-carrying input analog signal, or a first intermediate analog signal generated from the input analog signal, according to a transfer function (b1s+1)/(a2s2+a1s+1) to produce a filtered analog signal with reduced intersymbol interference where a1, a2, and b1 are non-zero filter parameters, and s is a frequency-transform variable;
• converting the filtered analog signal, or a second intermediate analog signal generated from the filtered analog signal, into an initial digital signal;
• equalizing the initial digital signal, or an intermediate digital signal generated from the initial digital signal, to produce an equalized digital signal as a stream of equalized digital values;
• and
• decoding the equalized digital values, or intermediate digital values generated from the equalized digital values, to produce a stream of symbols.

A method comprising:

• analog filtering a symbol-information-carrying input analog signal, or a first intermediate analog signal generated from the input analog signal, according to a transfer function (1−Vc)+VcPF(s) to produce a filtered analog signal with reduced intersymbol interference where Vc is a variable that varies adaptively between 0 and 1, PF(s) is an analog filter transfer function, and s is a frequency-transform variable;
• converting the filtered analog signal, or a second intermediate analog signal generated from the filtered analog signal, into an initial digital signal;
• equalizing the initial digital signal, or an intermediate digital signal generated from the initial digital signal, to produce an equalized digital signal as a stream of equalized digital values;
• and
• decoding the equalized digital values, or intermediate digital values generated from the equalized digital values, to produce a stream of symbols.

A method comprising:

• analog filtering a symbol-information-carrying input analog signal, or a first intermediate analog signal generated from the input analog signal, to produce a filtered analog signal according to an overall transfer function that includes the product of a plurality of component transfer functions (1−Vci)+VciPFi(s) where i is a running integer that runs from 1 to the number of component transfer functions, Vci is a variable that varies adaptively between 0 and 1, PFi(s) is an analog filter transfer function, and s is a frequency-transform variable;
• converting the filtered analog signal, or a second intermediate analog signal generated from the filtered analog signal, into an initial digital signal;
• equalizing the initial digital signal, or an intermediate digital signal generated from the initial digital signal, to produce an equalized digital signal as a stream of equalized digital values;
• and
• decoding the equalized digital values, or intermediate digital values generated from the equalized digital values, to produce a stream of symbols.