Dibinary encoding technique

Claim 2

In a data transmission system, the method of converting input non-synchronous two-level data to non-synchronous three-level data comprising the steps of: generating a negative image of said two-level data, and transmitting according to a predetermined probability factor either said input two-level data or said negative image two-level data, respectively, in response to a control signal embodying said predetermined probability factor independent of any of the characteristics of said two-level data.

Claim 3

The method as set forth in claim 1 wherein said probability factor is 0.5.

Claim 4

In a data transmission system, the method of converting input non-synchronous two-level data to non-synchronous three-level data comprising the steps of: generating a negative image of said two-level data, and transmitting according to a predetermined probability factor either said input two-level data or said negative image two-level data, respectively, in response to a control signal embodying said predetermined probability factor, said probability factor being dependent upon the statistical probability of occurrence of transitions in said control signal.

Claim 5

In a data transmission system, the method of converting input non-synchronous two-level data to non-synchronous three-level data comprising the steps of: generating a negative image of said two-level data, and transmitting according to a predetermined probability factor either said input two-level data or said negative image two-level data, respectively, in response to a control signal embodying said predetermined probability factor, said probability factor being dependent upon the statistical probability of occurrence of transitions in said control signal.

Claim 6

The method as set forth in claim 1 wherein said two-level data and said negative image two level data are transmitted alternately at a probability factor of 1.

Claim 7

A data transmission system comprising: a source of input two-level non-synchronous data signals, means for generating a negative image of said two-level data signals, and means for transmitting according to a predetermined probability factor either said two-level data signals or said negative image two-level data signals, respectively, as three-level data signals in response to a control signal embodying said predetermined probability factor, said probability factor being independent of any of the chararcteristics of said input two-level data, and said three-level data signals having a predetermined power density spectrum in direct relation to the power density spectrum of said input two-level data signals.

Claim 8

A data transmission system comprising: a source of input two-level non-synchronous data signals, means for generating a negative image of said two-level data signals, and means for transmitting according to a predetermined probability factor either said two-level data signals or said negative image two-level data signals, respectively, as three-level data signals in response to a control signal embodying said predetermined probability factor, said probability factor being independent of any of the chararcteristics of said input two-level data, and said three-level data signals having a predetermined power density spectrum in direct relation to the power density spectrum of said input two-level data signals.

Claim 9

The system as set forth in claim 5 wherein said probability factor is 0.5.

Claim 10

The system as set forth in claim 5 further including means for generating said control signal to thereby enable said transmitting means according to said predetermined probability factor.

Claim 11

The system as set forth in claim 7 wherein said generating means comprises noise generating means for generating random signals with an equal probability of being positive or negative, gating means responsive to said random transition signals and said two-level data signals for generating enabling signals for each positive going transition in said two-level data signals, and flip-flop switching means coupled to said gating means being set or reset in response to said enabling signals to generate said control signals to enable said transmitting means.

Claim 12

A data transmission system comprising: a source of two-level non-synchronous data signals, means for generating first and second enabling signals in response to said two-level data signals, said generating means comprising switching means responsive to the zero level portions of said two-level non-synchronous data signals, and means for transmitting said two-level data signals as three-level data signals in response to said first and second enabling signals, said transmitting means comprising gating means coupled to said two-level non-synchronous data signal source and said switching means for transmitting the positive portions of the two-level data waveform alternate in polarity about said zero level portions to generate said three-level data signal, said three-level data signals having a predetermined power density spectrum in direct relation to the power density spectrum of said two-level data signals.

Claim 13

A data transmission system comprising: a source of two-level non-synchronous data signals, means for generating first and second enabling signals in response to said two-level data signals, said generating means comprising switching means responsive to the zero level portions of said two-level non-synchronous data signals, and means for transmitting said two-level data signals as three-level data signals in response to said first and second enabling signals, said transmitting means comprising gating means coupled to said two-level non-synchronous data signal source and said switching means for transmitting the positive portions of the two-level data waveform alternate in polarity about said zero level portions to generate said three-level data signal, said three-level data signals having a predetermined power density spectrum in direct relation to the power density spectrum of said two-level data signals.

Claim 14

A data transmission system comprising: a source of two-level non-synchronous data signals, means for generating first and second enabling signals in response to said two-level data signals, said generating means comprising multivibrator means responsive to said two-level data signals and being enabled when said two-level data signal is zero and disabled when said two-level data signal is positive, and switching means coupled to said multivibrator means for generating a signal of a first polarity at an odd count of signals from said multivibrator means and for generating a signal of a second polarity at an even count of signals from said multivibrator means, and means for selectively transmitting said two-level data signals in response to said first and second enabling signals, respectively, said transmitting means comprising gating means coupled to said two-level non-synchronous data signal source and said switching means for transmitting the positive portions of said two-level data waveform varying in polarity to generate three-level data signals, said three-level data signals having a predetermined power density spectrum in direct relation to the power density spectrum of said two-level data signals.

Claim 15

A data transmission system comprising: a source of two-level non-synchronous data signals, means for generating first and second enabling signals in response to said two-level data signals, said generating means comprising multivibrator means responsive to said two-level data signals and being enabled when said two-level data signal is zero and disabled when said two-level data signal is positive, and switching means coupled to said multivibrator means for generating a signal of a first polarity at an odd count of signals from said multivibrator means and for generating a signal of a second polarity at an even count of signals from said multivibrator means, and means for selectively transmitting said two-level data signals in response to said first and second enabling signals, respectively, said transmitting means comprising gating means coupled to said two-level non-synchronous data signal source and said switching means for transmitting the positive portions of said two-level data waveform varying in polarity to generate three-level data signals, said three-level data signals having a predetermined power density spectrum in direct relation to the power density spectrum of said two-level data signals.

Claim 16

The system as set forth in claim 10 wherein said three-level data waveform has a power density spectrum of

Claim 17

In a data transmission system, the method of converting non-synchronous two-level data into non-synchronous multi-level data of more than three levels comprising the steps of: first successively changing the level of the multi-level data waveform for each positive transition and negative transition in said two-level data in staircase fashion to a first level limit in the multi-level data waveform, said multi-level data being greater than three-levels, and second successively changing the level of the multi-level data waveform for each positive transition and negative transition in said two-level data in staircase fashion from said first level limit to a second level limit in the multi-level waveform.

Claim 18

In a data transmission system, the method of converting non-synchronous two-level data into non-synchronous multi-level data of more than three levels comprising the steps of: first successively changing the level of the multi-level data waveform for each positive transition and negative transition in said two-level data in staircase fashion to a first level limit in the multi-level data waveform, said multi-level data being greater than three-levels, and second successively changing the level of the multi-level data waveform for each positive transition and negative transition in said two-level data in staircase fashion from said first level limit to a second level limit in the multi-level waveform.

Claim 19

In a data transmission system, the method of converting input non-synchronous two-level data into non-synchronous three-level data comprising the steps of: generating a negative image of said input two-level data, and transmitting either said two-level data or said negative image two-level data, respectively, according to the characteristics of a random transition control signal of predetermined probability factor independent of the characteristics of said two-level data.

Claim 20

In a data transmission system, the method of converting input non-synchronous two-level data into non-synchronous three-level data comprising the steps of: generating a negative image of said input two-level data, and transmitting either said two-level data or said negative image two-level data, respectively, according to the characteristics of a random transition control signal of predetermined probability factor independent of the characteristics of said two-level data.

Claim 21

In a data transmission system, the method of converting non-synchronous two-level data into non-synchronous three-level data comprising the steps of: generating first and second enabling signals in response to said two-level data signals, said step of generating comprising switching at transitions of like polarity of said two-level non-synchronous signals, and transmitting the positive portions of the two-level data waveform alternate in polarity about said zero level in response to said first and second enabling signals to generate said three-level data signal.

Claim 22

In a data transmission system, the method of converting non-synchronous two-level data into non-synchronous three-level data comprising the steps of: generating first and second enabling signals in response to said two-level data signals, said step of generating comprising switching at transitions of like polarity of said two-level non-synchronous signals, and transmitting the positive portions of the two-level data waveform alternate in polarity about said zero level in response to said first and second enabling signals to generate said three-level data signal.

Claim 23

A data transmission system comprising: a source of two-level non-synchronous data signals, means for generating first and second enabling signals in response to said two-level data signals, said generating means comprising means for switching at transitions of like polarity of said two-level non-synchronous data signals, and means for transmitting said two-level data signals as three-level data signals in response to said first and second enabling signals, said transmitting means comprising gating means coupled to said two-level non-synchronous data signal source and said switching means for transmitting the positive portions of the two-level data waveform alternate in polarity about said zero level portions.

Claim 24

A data transmission system comprising: a source of two-level non-synchronous data signals, means for generating first and second enabling signals in response to said two-level data signals, said generating means comprising means for switching at transitions of like polarity of said two-level non-synchronous data signals, and means for transmitting said two-level data signals as three-level data signals in response to said first and second enabling signals, said transmitting means comprising gating means coupled to said two-level non-synchronous data signal source and said switching means for transmitting the positive portions of the two-level data waveform alternate in polarity about said zero level portions.

Claim 25

In a data transmission system, the method of converting non-synchronous two-level data into non-synchronous three-level data comprising the steps of: generating first and second enabling signals in response to said two-level data signals by switching at the transitions of one of said two-level portions to the other of said two-level portions of said two-level non-synchronous data signals, and transmitting said two-level data signals in response to said first and second enabling signals by gating the positive portions of the two-level data waveform alternate in polarity about said zero level portions.

Claim 26

In a data transmission system, the method of converting non-synchronous two-level data into non-synchronous three-level data comprising the steps of: generating first and second enabling signals in response to said two-level data signals by switching at the transitions of one of said two-level portions to the other of said two-level portions of said two-level non-synchronous data signals, and transmitting said two-level data signals in response to said first and second enabling signals by gating the positive portions of the two-level data waveform alternate in polarity about said zero level portions.

Claim 27

In a data transmission system, the method of converting non-synchronous two-level data into non-synchronous three-level data comprising the steps of: generating first and second enabling signals in response to said two-level data signals, said step of generating comprising enabling a multivibrator circuit when said two-level data signal is zero and disabling said multivibrator circuit when said two-level data signal is positive, further generating a signal of a first polarity at an odd count of signals from said multivibrator circuit and further generating a signal of a second polarity at an even count of signals from said multivibrator circuit, and transmitting said two-level data signals in response to said first and second enabling signals, said step of transmitting comprising gating the positive portions of said two-level data waveform varying in polarity to generate said three-level data signals, said three-level data signals having a predetermined power density spectrum in direct relation to the power density spectrum of said two level data signals.

Claim 28

In a data transmission system, the method of converting non-synchronous two-level data into non-synchronous three-level data comprising the steps of: generating first and second enabling signals in response to said two-level data signals, said step of generating comprising enabling a multivibrator circuit when said two-level data signal is zero and disabling said multivibrator circuit when said two-level data signal is positive, further generating a signal of a first polarity at an odd count of signals from said multivibrator circuit and further generating a signal of a second polarity at an even count of signals from said multivibrator circuit, and transmitting said two-level data signals in response to said first and second enabling signals, said step of transmitting comprising gating the positive portions of said two-level data waveform varying in polarity to generate said three-level data signals, said three-level data signals having a predetermined power density spectrum in direct relation to the power density spectrum of said two level data signals.

Claim 29

In a facsimile system wherein copy is scanned to produce an analog signal train representative thereof, a system for reducing the bandwidth required for transmitting said analog signal train without clocking comprising: means for converting said analog signal train to a two amplitude level analog pulse train wherein each analog signal in said analog signal train exceeding a predetermined amplitude is converted to an analog pulse having one amplitude level and the same time duration as the analog signal from which it is derived exceeds said predetermined amplitude and each analog signal in said analog signal train which does not exceed said predetermined level is converted to a pulse having a second amplitude level and the same duration as the analog signal from which it is derived, means to which said two amplitude level analog pulse train is applied for inverting the phase of alternate pulses having said one amplitude level to a phase opposite to that of the remaining pulses having said one amplitude level while retaining the same time duration as the pulse from which it is derived, to provide a three amplitude level analog pulse train, means for transmitting said three amplitude level analog pulse train, means for receiving said three amplitude level analog pulse train, means for converting said received pulse train to a two amplitude level analog pulse train, and means for utilizing said two amplitude level analog pulse train for reproducing the copy which was scanned.

Claim 30

In a facsimile system wherein copy is scanned to produce an analog signal train representative thereof, a system for reducing the bandwidth required for transmitting said analog signal train without clocking comprising: means for converting said analog signal train to a two amplitude level analog pulse train wherein each analog signal in said analog signal train exceeding a predetermined amplitude is converted to an analog pulse having one amplitude level and the same time duration as the analog signal from which it is derived exceeds said predetermined amplitude and each analog signal in said analog signal train which does not exceed said predetermined level is converted to a pulse having a second amplitude level and the same duration as the analog signal from which it is derived, means to which said two amplitude level analog pulse train is applied for inverting the phase of alternate pulses having said one amplitude level to a phase opposite to that of the remaining pulses having said one amplitude level while retaining the same time duration as the pulse from which it is derived, to provide a three amplitude level analog pulse train, means for transmitting said three amplitude level analog pulse train, means for receiving said three amplitude level analog pulse train, means for converting said received pulse train to a two amplitude level analog pulse train, and means for utilizing said two amplitude level analog pulse train for reproducing the copy which was scanned.

Claim 31

A facsimile system as recited in claim 18 wherein said means to which said two amplitude level analog pulse train is applied for inverting the phase of alternate pulses having said one amplitude level to a phase opposite to that of the remaining pulses having said one amplitude level to provide a three amplitude level analog pulse train comprises: a first disenabled gate means, a second disenabled gate means, phase inverter means connected to said second disenabled gate means output, means for applying said two level pulse train simultaneously to said first and second disenabled gate means inputs, means responsive to successive pulses in said two level pulse train for alternately enabling said first and second disenabled gate means, and means for combining the outputs of said first disenabled gate means and said phase inverter means to produce a three level analog pulse train having phase inverted alternate pulses.

Claim 32

A system as recited in claim 19 wherein said means responsive to successive pulses in said two level pulse train for alternately enabling said first and second disenabled gate means includes a flip-flop circuit means having first and second outputs connected to said respective first and second gate means inputs for alternatively energizing said first and second gate means responsive to successive pulses.

Claim 35

In a facsimile system wherein copy is scanned for generating an analog signal train representing each scanning line, a method of reducing the bandwidth required for transmitting said analog signal train without signal clocking comprising: converting said analog signal train to a two amplitude level unclocked analog pulse train wherein analog signals exceeding a predetermined amplitude level are represented by pulses having one amplitude level and a pulse width determined by the interval over which the analog signal it represents exceeds said predetermined amplitude level and the analog signals not exceeding said predetermined level are represented by pulses having a second amplitude level and a pulse width determined by the interval over which said predetermined level is not exceeded, applying said two amplitude level unlocked analog pulse train to a first and second blocked path, successively alternately unblocking said first and second blocked paths responsive to successive one amplitude level pulses in said two amplitude level unclocked analog pulse train, phase inverting each one amplitude level pulse in said first blocked path, adding the outputs from said first and second blocked paths to produce a three level unclocked analog pulse train, transmitting said three level analog unclocked pulse train, receiving said transmitted three level unclocked analog pulse train, converting said three level analog unclocked pulse train back to said two amplitude level unclocked analog pulse train, and utilizing said two amplitude analog unclocked pulse train for reproducing said original copy.

Claim 36

In a facsimile system wherein copy is scanned for generating an analog signal train representing each scanning line, a method of reducing the bandwidth required for transmitting said analog signal train without signal clocking comprising: converting said analog signal train to a two amplitude level unclocked analog pulse train wherein analog signals exceeding a predetermined amplitude level are represented by pulses having one amplitude level and a pulse width determined by the interval over which the analog signal it represents exceeds said predetermined amplitude level and the analog signals not exceeding said predetermined level are represented by pulses having a second amplitude level and a pulse width determined by the interval over which said predetermined level is not exceeded, applying said two amplitude level unlocked analog pulse train to a first and second blocked path, successively alternately unblocking said first and second blocked paths responsive to successive one amplitude level pulses in said two amplitude level unclocked analog pulse train, phase inverting each one amplitude level pulse in said first blocked path, adding the outputs from said first and second blocked paths to produce a three level unclocked analog pulse train, transmitting said three level analog unclocked pulse train, receiving said transmitted three level unclocked analog pulse train, converting said three level analog unclocked pulse train back to said two amplitude level unclocked analog pulse train, and utilizing said two amplitude analog unclocked pulse train for reproducing said original copy.