US5956624A — Method and system for simultaneously broadcasting…

Claim 1

Independent Claim 170 words

A method of simultaneously transmitting an analog FM signal and a digitized wideband signal robust to multipath degradation and intersymbol interference within a predetermined broadcast band, the method comprising the steps of: a) producing the analog FM signal substantially centered about a center frequency of a predetermined broadcast band; b) generating a basis set of wideband mutually orthogonal pseudorandom basis signal waveforms of substantially equal length and having predetermined autocorrelation values and a predetermined spectral shape, the length of the waveforms in the set representing a baud, said predetermined spectral shape of the basis waveforms in the basis set including two spaced apart sections, one on each side of the center frequency; c) data modulating the wideband waveforms of the basis set so as to define digital data, the basis set substantially maintaining said predetermined spectral shape during said modulation; d) linearly combining the analog FM signal and the modulated waveforms to produce a composite signal; and e) transmitting the composite signal through atmospheric free-space to at least one receiver.

Claim 2

Independent Claim 170 words

A method of simultaneously transmitting an analog FM signal and a digitized wideband signal robust to multipath degradation and intersymbol interference within a predetermined broadcast band, the method comprising the steps of: a) producing the analog FM signal substantially centered about a center frequency of a predetermined broadcast band; b) generating a basis set of wideband mutually orthogonal pseudorandom basis signal waveforms of substantially equal length and having predetermined autocorrelation values and a predetermined spectral shape, the length of the waveforms in the set representing a baud, said predetermined spectral shape of the basis waveforms in the basis set including two spaced apart sections, one on each side of the center frequency; c) data modulating the wideband waveforms of the basis set so as to define digital data, the basis set substantially maintaining said predetermined spectral shape during said modulation; d) linearly combining the analog FM signal and the modulated waveforms to produce a composite signal; and e) transmitting the composite signal through atmospheric free-space to at least one receiver.

Claim 3

Dependent Claim 39 words

The method of claim 1, including the step of: defining the digital data by variable gain modulating the waveforms so that predetermined autocorrelation and orthogonal characteristics of the spectrally shaped and modulated waveforms are substantially maintained through said modulation.

Claim 4

Dependent Claim 38 words

The method of claim 2, including the step of: variable gain modulating the waveform by phase modulation, and said step b) including generating said basis set so as to have a crosscorrelation/autocorrelation ratio of less than about 0.001.

Claim 5

Dependent Claim 59 words

The method of claim 1, including the step of: spacing the sections of the mutually orthogonal spectrally shaped and modulated set of waveforms from about 50 kHz to about 150 kHz from the center frequency, and maintaining the predetermined autocorrelation values to maintain a crosscorrelation/autocorrelation ratio of said set to be less than about 0.002 for each waveform pair.

Claim 6

Dependent Claim 30 words

The method of claim 4, including the step of: utilizing the waveforms as digital carriers having a maximum amplitude at least about 20 dB below that of the FM signal.

Claim 7

Dependent Claim 76 words

The method of claim 5, including the steps of: positioning the sections substantially symmetrically about the center frequency, the sections being spaced from about 75 kHz to 125 kHz from the center frequency; forming the sections so that the maximum amplitude of the waveforms is at least about 25 dB below that of the FM signal; and forming said set so as to have a crosscorrelation/autocorrelation ratio of less than about 0.001 for each waveform pair.

Claim 8

Dependent Claim 162 words

The method of claim 1, including the step of: forming the set of wideband mutually orthogonal spectrally shaped basis signal waveforms by: i) generating a plurality of pseudorandom sequences having at least about 50 samples per sequence; ii) spectrally shaping each of the generated pseudorandom sequences into the two spaced apart sections by convolving each pseudorandom sequence with a shaping function so that the resulting spectrally shaped pseudorandom sequences have predetermined autocorrelation properties; iii) arranging the shaped pseudorandom sequences as columns of a matrix, the matrix having a greater number of rows than columns, the number of columns of said matrix substantially representing the number of pseudorandom spectrally shaped sequences, and the number of rows substantially representing the number of samples in sequence; and iv) decomposing the matrix by singular value decomposition into the product of three other matrices so that a substantial number of the columns of one of the other matrices represents the basis set of spectrally shaped orthogonal sequences.

Claim 9

Dependent Claim 28 words

The method of claim 7, including the step of: determining the maximum length of each pseudorandom sequence by the ratio of the baud interval to the sample interval.

Claim 10

Dependent Claim 178 words

A transmitter for broadcasting a signal including an analog FM signal portion and a digital signal portion robust to multipath degradation, the transmitter comprising: means for generating the analog FM signal substantially centered about the center frequency of a predetermined broadcast band; means for generating a basis wideband set of substantially orthogonal spectrally shaped pseudorandom waveforms having predetermined autocorrelation properties, the basis waveforms being spectrally shaped so as to define a first portion on one side of the center frequency within the broadcast band and a second portion on an opposite side of the center frequency within the broadcast band so that the analog FM signal may be disposed substantially between the first and second portions of the spectrally shaped waveforms; modulation means for digitally modulating the basis set of spectrally shaped substantially orthogonal wideband waveforms to define the digital signals, the modulated waveforms maintaining their spectral shaping through the modulation; means for combining the analog FM and digital signals to form a composite signal; and broadcast means for transmitting the composite signal to at least one receiver.

Claim 11

Dependent Claim 178 words

A transmitter for broadcasting a signal including an analog FM signal portion and a digital signal portion robust to multipath degradation, the transmitter comprising: means for generating the analog FM signal substantially centered about the center frequency of a predetermined broadcast band; means for generating a basis wideband set of substantially orthogonal spectrally shaped pseudorandom waveforms having predetermined autocorrelation properties, the basis waveforms being spectrally shaped so as to define a first portion on one side of the center frequency within the broadcast band and a second portion on an opposite side of the center frequency within the broadcast band so that the analog FM signal may be disposed substantially between the first and second portions of the spectrally shaped waveforms; modulation means for digitally modulating the basis set of spectrally shaped substantially orthogonal wideband waveforms to define the digital signals, the modulated waveforms maintaining their spectral shaping through the modulation; means for combining the analog FM and digital signals to form a composite signal; and broadcast means for transmitting the composite signal to at least one receiver.

Claim 12

Dependent Claim 64 words

The transmitter of claim 9, wherein said means for generating said basis set spaces the first and second spectrally shaped portions of the set of digitally modulated wideband waveforms from about 50 kHz-200 kHz away from the center frequency, and sets the maximum amplitude of the digital signals at least about 20 dB below that of the FM signal centered about the center frequency.

Claim 13

Dependent Claim 47 words

The transmitter of claim 10, wherein the predetermined broadcast band extends less than about 350 kHz on either side of the center frequency, and the composite signal is substantially disposed within the broadcast band, and wherein said set has a crosscorrelation/autocorrelation ratio of less than about 0.001.

Claim 14

Dependent Claim 122 words

The transmitter of claim 9, wherein said means for generating a wideband set determines the basis wideband set of substantially orthogonal spectrally shaped pseudorandom waveforms by: a) generating a plurality of random number wideband pseudorandom sequences via a plurality of samples; b) spectrally shaping each of the generated pseudorandom sequences into the first and second portions disposed on opposite sides of the center frequency; c) arranging the shaped pseudorandom sequences as columns of a matrix, the matrix having a greater number of rows than columns; d) decomposing the matrix by singular value decomposition into the product of three additional matrices, wherein a substantial number of the columns of one of the additional matrices represents the basis wideband set of spectrally shaped waveforms.

Claim 15

Dependent Claim 47 words

The transmitter of claim 12, wherein said modulation means phase modulates the waveforms of the basis set in order to define the digital signals to be transmitted, and wherein said basis set includes at least about 35 different waveforms, each waveform representing a different channel or carrier.

Claim 16

Independent Claim 107 words

A method for implementing a high spectral efficiency digital communication link in channels with known colored interference and multipath, the method comprising the steps of: a) determining the spectral content of the known colored interference; b) generating a basis set of wideband mutually orthogonal sequences, said sequences having predetermined autocorrelation characteristics; c) spectrally shaping said basis set to complement the colored interference; d) setting the baud interval, or length of said sequences, to a value greater than a determined longest expected multipath delay; e) data modulating said sequences; and f) transmitting said modulated sequences as waveforms over the digital communication link from a transmitter to a receiver.

Claim 17

Independent Claim 107 words

A method for implementing a high spectral efficiency digital communication link in channels with known colored interference and multipath, the method comprising the steps of: a) determining the spectral content of the known colored interference; b) generating a basis set of wideband mutually orthogonal sequences, said sequences having predetermined autocorrelation characteristics; c) spectrally shaping said basis set to complement the colored interference; d) setting the baud interval, or length of said sequences, to a value greater than a determined longest expected multipath delay; e) data modulating said sequences; and f) transmitting said modulated sequences as waveforms over the digital communication link from a transmitter to a receiver.

Claim 18

Dependent Claim 49 words

The method fo claim 14, wherein step c) includes spectrally shaping said set into at least two spaced apart portions whereby said colored interference is disposed between said two spaced apart portions so as to allow said digital data to be effectively transmitted in environments having known colored interference.

Claim 19

Dependent Claim 44 words

The method of claim 14, further including the step of g) summing together a wideband reference signal with said modulated waveforms of said set so that said reference signal is spectrally confined substantially to the extent of the pseudorandom modulated waveforms of said set.

Claim 20

Dependent Claim 41 words

The method of claim 16, further including the step of h) measuring the frequency of said reference signal in said receiver and accordingly adjusting a baud clock in said receiver so as to ensure data synchronization in said receiver and transmitter.

Claim 21

Independent Claim 200 words

A method of transmitting a digitized wideband signal robust to multipath degradation and intersymbol interference within a predetermined broadcast band, the method comprising: generating a basis set of wideband mutually orthogonal pseudorandom basis signal waveforms of substantially equal length and having predetermined autocorrelation values and a predetermined spectral shape, the length of the waveforms in the set representing a baud, the waveforms comprise codes having more than two values, the generating the basis set includes a) generating a plurality of random number wideband pseudorandom sequences via a plurality of samples, b) spectrally shaping each of the generated pseudorandom sequences into the first and second portions disposed on opposite sides of the center frequency, c) arranging the shaped pseudorandom sequences as columns of a matrix, the matrix having a greater number of rows than columns, and d) decomposing the matrix by singular value decomposition into the product of three additional matrices, wherein a substantial number of the columns of one of the additional matrices represents the basis wideband set of spectrally shaped waveforms; and data modulating the wideband waveforms of the basis set so as to define digital data, the basis set substantially maintaining said predetermined spectral shape during said modulation.

Claim 22

Independent Claim 200 words

A method of transmitting a digitized wideband signal robust to multipath degradation and intersymbol interference within a predetermined broadcast band, the method comprising: generating a basis set of wideband mutually orthogonal pseudorandom basis signal waveforms of substantially equal length and having predetermined autocorrelation values and a predetermined spectral shape, the length of the waveforms in the set representing a baud, the waveforms comprise codes having more than two values, the generating the basis set includes a) generating a plurality of random number wideband pseudorandom sequences via a plurality of samples, b) spectrally shaping each of the generated pseudorandom sequences into the first and second portions disposed on opposite sides of the center frequency, c) arranging the shaped pseudorandom sequences as columns of a matrix, the matrix having a greater number of rows than columns, and d) decomposing the matrix by singular value decomposition into the product of three additional matrices, wherein a substantial number of the columns of one of the additional matrices represents the basis wideband set of spectrally shaped waveforms; and data modulating the wideband waveforms of the basis set so as to define digital data, the basis set substantially maintaining said predetermined spectral shape during said modulation.

Claim 23

Dependent Claim 46 words

The method of claim 18, wherein said modulator phase modulates the waveforms of the basis set in order to define the digital signals to be transmitted, and wherein said basis set includes at least about 35 different waveforms, each waveform representing a different channel or carrier.

Annuity Stage	Window Opens	Payment Deadline	Surcharge Period Until	Estimated Fee	Status
3.5 Years (Year 4)	2002-09-20	2003-03-22	2003-09-21	$2000.00	Window Closed / Lapsed
7.5 Years (Year 8)	2006-09-20	2007-03-22	2007-09-21	$3760.00	Window Closed / Lapsed
11.5 Years (Year 12)	2010-09-20	2011-03-22	2011-09-21	$7700.00	Window Closed / Lapsed

Method and system for simultaneously broadcasting and receiving digital and analog signals

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