Single-sideband modulation system

Claim 2

A single-sideband modulation system including a plurality of signal channels responsive to applied baseband signals, each channel comprising: means for sampling an applied baseband signal; means for selectively modulating said sampled baseband signal; and a pair of circuit branches, each branch including multirate digital filter means and modulation means for processing said selectively modulated sampled baseband signal.

Claim 3

The system as defined in claim 1 wherein said multirate digital filter means comprises: a first digital filter operating at a first predetermined computation rate; and a second digital filter, serially connected to said first digital filter, operating at a second predetermined computation rate.

Claim 4

The multirate digital filter of claim 2 where said first predetermined computation rate is proportional to the basic Nyquist rate of said baseband signal and said second predetermined computation rate is a preselected multiple of said first computation rate.

Claim 5

The system as defined in claim 1 wherein said multirate digital filter means comprises a recursive digital filter in casCade with a nonrecursive digital filter.

Claim 6

A single-sideband modulation system including a plurality of signal channels responsive to applied baseband signals and means for combining signals processed by said signal channels, each channel comprising: means for sampling an applied baseband signal; means for modulating said sampled baseband signal; and a pair of circuit branches, each branch including multirate digital filter means for altering said modulated sampled baseband signal and means for modulating said altered signal with predetermined sampled modulating functions.

Claim 7

A single-sideband modulation system including a plurality of signal channels responsive to applied baseband signals and means for combining signals processed by said signal channels, each channel comprising: means for sampling an applied baseband signal; means for modulating said sampled baseband signal; and a pair of circuit branches, each branch including multirate digital filter means for altering said modulated sampled baseband signal and means for modulating said altered signal with predetermined sampled modulating functions.

Claim 8

The system as defined in claim 5 wherein said multirate digital filter means comprises a first digital filter operating at a first predetermined computation rate connected in cascade with a second digital filter operating at a second predetermined computation rate.

Claim 9

A multirate digital filter of claim 6 where said first predetermined computation rate is proportional to the basic Nyquist rate of said baseband signal and said second predetermined computation rate is a preselected multiple of said first computation rate.

Claim 10

The system as defined in claim 5 wherein said multirate digital filter means comprises a recursive digital filter in cascade with a nonrecursive digital filter.

Claim 11

Single-sideband modulation apparatus comprising: a plurality of channel means, each of said channel means including sampling means, commutation means, and a pair of circuit branches responsive to signals developed by said commutation means, said circuit branches each further comprising first digital filter means operating at a predetermined sampling rate and second digital filter means operating at a preselected multiple of said predetermined sampling rate; means for modulating signals emanating from said second digital filter means; and means for combining said modulated signals.

Claim 12

Single-sideband modulation apparatus comprising: a plurality of channel means, each of said channel means including sampling means, commutation means, and a pair of circuit branches responsive to signals developed by said commutation means, said circuit branches each further comprising first digital filter means operating at a predetermined sampling rate and second digital filter means operating at a preselected multiple of said predetermined sampling rate; means for modulating signals emanating from said second digital filter means; and means for combining said modulated signals.

Claim 13

Single-sideband modulation apparatus comprising: a plurality of channel means, each of said channel means including sampling means, modulation means, and a pair of circuit branches responsive to signals developed by said modulation means, each of said circuit branches further comprising digital filter means operating at a predetermined sampling rate; means for selectively modulating signals emanating from said digital filter means; means for combining said selectivity modulated signals; and means for developing a signal proportional to the discrete convolution of said combined signals.

Claim 14

Single-sideband modulation apparatus comprising: a plurality of channel means, each of said channel means including sampling means, modulation means, and a pair of circuit branches responsive to signals developed by said modulation means, each of said circuit branches further comprising digital filter means operating at a predetermined sampling rate; means for selectively modulating signals emanating from said digital filter means; means for combining said selectivity modulated signals; and means for developing a signal proportional to the discrete convolution of said combined signals.

Claim 15

A single-sideband modulation system comprising; a plurality of signal channels, each channel responsive to an applied baseband signal and including means for sampling said baseband signal, commutation means for selectively modulating said sampled baseband signal, and a pair of circuit branches responsive to said commutation means, each circuit branch comprising digital filter means; means for generating predetermined modulating signals; means for developing a signal proportional to the product of said modulating signals and signals from said digital filter means; means for developing a signal proportional to the sum of said proportional product signals; and means for developing a signal proportional to the discrete convolution of said proportional sum signal.

Claim 16

A single-sideband modulation system comprising; a plurality of signal channels, each channel responsive to an applied baseband signal and including means for sampling said baseband signal, commutation means for selectively modulating said sampled baseband signal, and a pair of circuit branches responsive to said commutation means, each circuit branch comprising digital filter means; means for generating predetermined modulating signals; means for developing a signal proportional to the product of said modulating signals and signals from said digital filter means; means for developing a signal proportional to the sum of said proportional product signals; and means for developing a signal proportional to the discrete convolution of said proportional sum signal.

Claim 17

The system of claim 11 wherein said digital filter means operates at a computation rate proportional to the basic Nyquist rate of said baseband signal.

Claim 18

The system as defined in claim 11 wherein said digital filter means comprises a recursive digital filter.

Claim 19

A modulation system comprising; a plurality of signal channels, each channel responsive to an applied baseband signal and including means for sampling said baseband signal, means for selectively modulating said sampled baseband signal, and digital filter means for processing said modulated, sampled baseband signal; means for generating predetermined sampled functions; means for developing a signal proportional to tHe sum of the product of signals processed by said digital filter means and said sampled functions; and means for developing a signal proportional to a predetermined convolution of said proportional sum signal.

Claim 20

A modulation system comprising; a plurality of signal channels, each channel responsive to an applied baseband signal and including means for sampling said baseband signal, means for selectively modulating said sampled baseband signal, and digital filter means for processing said modulated, sampled baseband signal; means for generating predetermined sampled functions; means for developing a signal proportional to tHe sum of the product of signals processed by said digital filter means and said sampled functions; and means for developing a signal proportional to a predetermined convolution of said proportional sum signal.

Claim 21

The system as defined in claim 14 wherein said digital filter means comprises a pair of parallel connected digital filters operating at a predetermined computation rate.

Claim 22

The digital filter means of claim 15 wherein said predetermined computation rate is proportional to the basic Nyquist rate of said baseband signal.

Claim 23

The system as defined in claim 14 wherein said digital filter means comprises a pair of parallel connected recursive digital filters.

Claim 24

In a frequency division multiplex, single-sideband carrier system wherein a plurality of baseband signals are applied to a corresponding plurality of carrier channels which include means for sampling said baseband signals and means for modulating said sampled baseband signals, the improvement comprising: digital filter means responsive to each of said modulating means; a source of a plurality of preselected sampled modulating signal functions; means for forming a signal proportional to the sum of the product of signals, emanating from said digital filter means, and said sampled modulating signal functions; and means for forming the discrete convolution of said signal sum to develop a group of single-sideband modulated signals.

Claim 25

In a frequency division multiplex, single-sideband carrier system wherein a plurality of baseband signals are applied to a corresponding plurality of carrier channels which include means for sampling said baseband signals and means for modulating said sampled baseband signals, the improvement comprising: digital filter means responsive to each of said modulating means; a source of a plurality of preselected sampled modulating signal functions; means for forming a signal proportional to the sum of the product of signals, emanating from said digital filter means, and said sampled modulating signal functions; and means for forming the discrete convolution of said signal sum to develop a group of single-sideband modulated signals.

Claim 26

A single-sideband modulation system including a plurality of signal channels responsive to applied baseband signals, each channel comprising: means for sampling an applied baseband signal; means for selectively modulating said sampled baseband signal; multirate digital filter means for processing said modulated, sampled baseband signal; and means for modulating said processed signal.

Claim 27

A single-sideband modulation system including a plurality of signal channels responsive to applied baseband signals, each channel comprising: means for sampling an applied baseband signal; means for selectively modulating said sampled baseband signal; multirate digital filter means for processing said modulated, sampled baseband signal; and means for modulating said processed signal.

Claim 28

In a frequency division multiplex, single-sideband carrier system wherein a plurality of baseband signals are applied to a corresponding plurality of carrier channels which include means for sampling said baseband signals and means for modulating said sampled baseband signals, the improvement comprising; digital filter means connected to each of said modulating means for processing said sampled baseband signals; and means for forming the discrete convolution of said processed signals to develop a group of single-sideband modulated signals.

Claim 29

In a frequency division multiplex, single-sideband carrier system wherein a plurality of baseband signals are applied to a corresponding plurality of carrier channels which include means for sampling said baseband signals and means for modulating said sampled baseband signals, the improvement comprising; digital filter means connected to each of said modulating means for processing said sampled baseband signals; and means for forming the discrete convolution of said processed signals to develop a group of single-sideband modulated signals.