Adaptive method of and means for recovering digital signals

Claim 5

A method as defined in claim 2 wherein said incoming data flow is demodulated, under the control of a locally generated phase signal, from a phase-modulated carrier arriving over said transmission channel, comprising the further step of continuously optimizing said phase signal under the joint control of said error signal and said reference signal.

Claim 6

A receiver for an incoming data flow phase-modulated on a carrier arriving over a transmission channel, comprising: demodulating means connected to said channel for recovering said data flow; sampling means connected to said demodulating means for producing a train of raw data pulses under the control of a locally generated timing signal; equalizing means connected to said sampling means for optimizing said raw data pulses by recursive filtering over a multiplicity of sampling cycles under the control of adaptive parameters including a gain coefficient and a channel coefficient, said equalizing means having a first output emitting the optimized data pulses, a second output emitting a reference signal internally synthesized from the vector sum of said raw data pulses weighted by said channel coefficient over said multiplicity of sampling cycles, and a third output emitting an updating signal internally synthesized from the vector sum of the differences between said raw data pulses and said reference signal obtained over said multiplicity of sampling cycles; quantizing means connected to said first output for converting said optimized data pulses into outgoing data pulses; storage means connected to said quantizing means for preserving said outgoing data pulses for a period corresponding to said multiplicity of sampling cycles; adder means connected to said storage means and to said second output for differentially combining the preserved data pulses with said reference signal to produce an error signal; a first feedback loop with input connections to said adder means and to said second output for delivering to a control input of said demodulating means an optimized phase signal derived from said error and reference signals; a second feedback loop with input connections to said adder means and to said third output for delivering to said equalizing means an optimizing gain coefficient derived from said error and updating signals; and a third feedback loop with input connections to said sampling means and to said storage means for delivering to said equalizing means an optimized channel coefficient derived from said raw and stored data pulses.

Claim 7

A receiver for an incoming data flow phase-modulated on a carrier arriving over a transmission channel, comprising: demodulating means connected to said channel for recovering said data flow; sampling means connected to said demodulating means for producing a train of raw data pulses under the control of a locally generated timing signal; equalizing means connected to said sampling means for optimizing said raw data pulses by recursive filtering over a multiplicity of sampling cycles under the control of adaptive parameters including a gain coefficient and a channel coefficient, said equalizing means having a first output emitting the optimized data pulses, a second output emitting a reference signal internally synthesized from the vector sum of said raw data pulses weighted by said channel coefficient over said multiplicity of sampling cycles, and a third output emitting an updating signal internally synthesized from the vector sum of the differences between said raw data pulses and said reference signal obtained over said multiplicity of sampling cycles; quantizing means connected to said first output for converting said optimized data pulses into outgoing data pulses; storage means connected to said quantizing means for preserving said outgoing data pulses for a period corresponding to said multiplicity of sampling cycles; adder means connected to said storage means and to said second output for differentially combining the preserved data pulses with said reference signal to produce an error signal; a first feedback loop with input connections to said adder means and to said second output for delivering to a control input of said demodulating means an optimized phase signal derived from said error and reference signals; a second feedback loop with input connections to said adder means and to said third output for delivering to said equalizing means an optimizing gain coefficient derived from said error and updating signals; and a third feedback loop with input connections to said sampling means and to said storage means for delivering to said equalizing means an optimized channel coefficient derived from said raw and stored data pulses.

Claim 8

A receiver as claimed in claim 4 wherein said third feedback loop comprises summing means in the input connection thereof extending to said sampling means, a cumulative multiplier working into said summing means, and a noncumulative multiplier with inputs tied to said summing means and to the input connection extending to said storage means for generating said optimizedchannel coefficient, said cumulative multiplier having inputs tied to the last-mentioned input connection and to the output of said noncumulative multiplier.

Claim 9

A receiver for an incoming data flow arriving over a transmission channel, comprising: input means for recovering digital signals from said data flow; differentiation means connected to said input means for obtaining the derivative of said digital signals with respect to time; first and second sampling means respectively connected to said input means and to said differentiation means for producing a train of raw data pulses and a train of raw differential pulses; first and second equalizing means respectively connected to said first and second sampling means for optimizing said raw data pulses and said raw differential pulses over a multiplicity of sampling cycles under the control of adaptive parameters including a gain coefficient and a channel coefficient, said first equalizing means having a first output emitting the optimized data pulses, a second output emitting a reference signal internally synthesized from the vector sum of said raw data pulses weighted by said channel coefficient over said multiplicity of sampling cycles, and a third output emitting an updating signal internally synthesized from the vector sum of the differences between said raw data pulses and said reference signal obtained over said multiplicity of sampling cycles; quantizing means connected to said first output for converting said optimized data pulses into outgoing data pulses; storage means connected to said quantizing means for preserving said outgoing data pulses for a period corresponding to said multiplicity of sampling cycles; adder means connected to said storage means and to said second output for differentially combining the preserved data pulses with said reference signal to produce an error signal; a first feedback loop with input connections to said adder means and to said third output for delivering to said first and second equalizing means an optimized gain coefficient derived from said error and updating signals; a second feedback loop with input connections to said first sampling means and to said storage means for delivering to said first and second equalizing means an optimized channel coefficient derived from said raw and stored data pulses; and a third feedback loop with input connections to said adder means and to said second equalizer means for delivering to said first and second sampling means an optimized timing signal derived from said error signal and from the optimized differential pulses.

Claim 10

A receiver for an incoming data flow arriving over a transmission channel, comprising: input means for recovering digital signals from said data flow; differentiation means connected to said input means for obtaining the derivative of said digital signals with respect to time; first and second sampling means respectively connected to said input means and to said differentiation means for producing a train of raw data pulses and a train of raw differential pulses; first and second equalizing means respectively connected to said first and second sampling means for optimizing said raw data pulses and said raw differential pulses over a multiplicity of sampling cycles under the control of adaptive parameters including a gain coefficient and a channel coefficient, said first equalizing means having a first output emitting the optimized data pulses, a second output emitting a reference signal internally synthesized from the vector sum of said raw data pulses weighted by said channel coefficient over said multiplicity of sampling cycles, and a third output emitting an updating signal internally synthesized from the vector sum of the differences between said raw data pulses and said reference signal obtained over said multiplicity of sampling cycles; quantizing means connected to said first output for converting said optimized data pulses into outgoing data pulses; storage means connected to said quantizing means for preserving said outgoing data pulses for a period corresponding to said multiplicity of sampling cycles; adder means connected to said storage means and to said second output for differentially combining the preserved data pulses with said reference signal to produce an error signal; a first feedback loop with input connections to said adder means and to said third output for delivering to said first and second equalizing means an optimized gain coefficient derived from said error and updating signals; a second feedback loop with input connections to said first sampling means and to said storage means for delivering to said first and second equalizing means an optimized channel coefficient derived from said raw and stored data pulses; and a third feedback loop with input connections to said adder means and to said second equalizer means for delivering to said first and second sampling means an optimized timing signal derived from said error signal and from the optimized differential pulses.

Claim 11

A receiver as defined in claim 6 wherein said input means includes a demodulator for recovering said digital signals from an incoming carrier phase-modulated therewith, further comprising a fourth feedback loop with input connections to said adder means and to said second output for delivering to a control input of said demodulator an optimized phase signal derived from said error and reference signals.

Claim 12

A receiver as defined in claim 7 wherein each of said feedback loops comprises a cumulative multiplier.

Claim 13

A receiver as defined in claim 7, further comprising a local test-signal generator and switchover means effective during an acquisition phase, preceding an operating phase, to connect said local generator in lieu of said quantizing means to said storage means.

Claim 14

A receiver as defined in claim 9 wherein each of said feedback loops includes delay means in one of its input connections and switch means synchronized with said switchover means for bypassing said delay means in said acquisition phase.