Method and apparatus for transmitting coded information

• US 5,050,188 A
• Filed: 06/07/1988
• Issued: 09/17/1991
• Est. Priority Date: 06/12/1987
• Status: Expired due to Fees

• Current Assignee: Josef Dirr
• Original Assignee: Josef Dirr
• Inventors: Dirr, Josef
• Primary Examiner(s): Chin, Stephen
• Application Number:
  US07/203,710
• Time in Patent Office: 1,197 Days
• Field of Search: 370/24, 370/27, 370/29, 370/30, 370/32, 370/20, 375/39, 375/61, 375/22, 375/24, 375/37, 375/38, 375/41, 358/12, 358/13, 358/16
• US Class Current: 375/260
• CPC Class Codes: H04L 27/24 Half-wave signalling systems
• CPC Class Codes: H04L 27/34 Amplitude- and phase-modulated carrier systems, e.g. quadrature-amplitude modulated carrier systems
• CPC Class Codes: H04N 11/042 Codec means
• CPC Class Codes: H04N 21/2383 Channel coding or modulation of digital bit-stream, e.g. QPSK modulation arrangements for detecting or preventing errors in the information received by adapting the channel coding H04L1/0009; analogue front ends or means for connecting modulators, demodulators or transceivers to a transmission line H04L27/0002
• CPC Class Codes: H04N 21/4382 Demodulation or channel decoding, e.g. QPSK demodulation analog front ends or means for connecting modulators, demodulators or transceivers to a transmission line H04L27/0002
• CPC Class Codes: H04N 7/12 Systems in which the television signal is transmitted via one channel or a plurality of parallel channels, the bandwidth of each channel being less than the bandwidth of the television signal H04N7/24 takes precedence

Abstract

In the transmission of information, particularly long-distance speech signals, between a first and a second station, the information is transmitted from the first to the second station by means of a code alternating current of predetermined frequency and phase-state, and from the second station to the first station by means of a code alternating current which has the predetermined frequency and a phase shifted by 90° with respect to the predetermined phase. The phase of the code alternating current transmitted from the second to the first station can be driven by means of the phase of the code alternating current transmitted from the first to the second station. The code alternating currents may contain code elements in the form of half waves or periods of differentiated amplitudes of the code alternating current, which is essentially sinusoidal. In order to use multiplication, two code-alternating-currents, whose phases are shifted by 90° will respect to each other, can be combined into one sum alternating current of the resulting phase, and to this sum alternating current at least one further code alternating current can be added, whose phase is shifted by 90° with respect to the resulting phase of the sum alternating current. The addition of further code alternating currents can be repeated, as long as the error-frequency during demodulation at the receiving end remains sufficiently low.

Claims

1. Process for the simultaneous transmission of first information from a first to a second station and of second information from the second to the first station over a single transmission path, comprising the following steps:

carrying out the following steps in said first station;

(a) producing an essentially sinusoidal first signal having a predetermined frequency as well as a predetermined phase and consists of a sequence of oscillation periods each of which at any given time contains two half-waves following one another with predetermined duration and opposite polarity, wherein said half-waves are able to take on at least two different discrete amplitude values which set forth a code representing said first information, and wherein all amplitude values are greater than zero, (b) transmitting said first signal from said first station to said second station over said single transmission path,

carrying out the following steps in said second station;

(a) obtaining a second sinusoidal oscillation having said predetermined frequency and phase by passing the transmitted first signal through separation means, (b) decoding the transmitted first signal in order to retrieve said first information, (c) feeding said second sinusoidal oscillation as an input signal into a 90-degree-phase shifter, which delivers an output signal, phase shifted by 90 degrees with respect to said input signal and thus shifting the phase of said second sinusoidal oscillation by 90 degrees, (d) producing an essentially sinusoidal second signal out of the phase-shifted second oscillation, wherein said second signal has the phase of the phase-shifted second oscillation and the predetermined frequency and consists of a sequence of oscillation-periods, each of which at any given time contains two half-waves following on each other with predetermined duration and opposite polarities, wherein said half-waves are able to take on at least two different discrete amplitudes, which set forth a code representing said second information, and wherein all amplitude values are greater than zero, (e) transmitting said second signal over said single transmission path to said first station, and carrying out the following step in said first station;

decoding the transmitted second signal in order to retrieve said second information.

2. Process according to claim 1 comprising the following additional step in said second station:

compensating (58, FIG.

     3) the signal to be transmitted by the signal received.

3. Process according to claim 1, wherein said transmission path includes a wireless transmission path.

4. Process for the simultaneous transmission of first information from a first to a second station and of second information from the second to the first station over a single transmission path, comprising the following steps:

carrying out the following steps in said first station;

(a) producing an essentially sinusoidal first signal having a predetermined frequency as well as a predetermined phase and consists of a sequence of oscillation periods each of which at any given time contains two half-waves following one another with predetermined duration and opposite polarity, wherein said half-waves are able to take on at least two different discrete amplitude values which set forth a code representing said first information, and wherein all amplitude values are greater than zero, (b) transmitting said first signal from said first station to said second station over said single transmission path,

carrying out the following steps in said second station;

(a) obtaining a second sinusoidal oscillation having said predetermined frequency and phase by a resistance-arrangement adapted to apportion the transmitted first signal, (b) decoding the transmitted first signal in order to retrieve said first information, (c) feeding said second sinusoidal oscillation as an input signal into a 90-degree-phase shifter, which delivers an output signal, phase shifted by 90 degrees with respect to said input signal and thus shifting the phase of said second sinusoidal oscillation by 90 degrees, (d) producing an essentially sinusoidal second signal out of the phase-shifted second oscillation, wherein said second signal has the phase of the phase-shifted second oscillation and the predetermined frequency and consists of a sequence of oscillation-periods, each of which at any given time contains two half-waves following on each other with predetermined duration and opposite polarities, wherein said half-waves are able to take on at least two different discrete amplitudes, which set forth a code representing said second information, and wherein all amplitude values are greater than zero, (e) transmitting said second signal over said single transmission path to said first station, and

carrying out the following step in said first station;

decoding the transmitted second signal in order to retrieve said second information.

5. Process according to claim 4, wherein said transmission path includes a wireless transmission path.

6. Process for the transmission of information from several subscribers over an appropriate connection to a transfer system, comprising the following steps:

(a) translating information which is to be transmitted form one predetermined subscriber on the transfer system into a coded alternating current signal in which at least one of two half-waves of each period forms a code element of a code setting forth said information, (b) translating information which is to be transmitted from the transfer system to a predetermined subscriber into a coded alternating current signal in which at least one of two half-waves of each period forms a code element of a code setting forth said information, (c) synchronizing the coded alternating current signal from one subscriber and the coded alternating current signal from the transfer system so that said signals have a relative phase displacement of 90 degrees by passing the coded alternating current signal from one subscriber or the coded alternating current signal from the transfer system through a phase shifter, (d) selectively receiving the coded alternating current signal transmitted from the transfer system to the subscriber at the location of the subscriber, (e) decoding the coded alternating current signal transmitted from the transfer system to a predetermined subscriber and at the location of this subscriber, (f) selectively receiving the coded alternating current signal transmitted from the subscriber to the transfer system at the location of the transfer system, and (g) decoding the coded alternating current signal transmitted from the subscriber to the transfer system.

7. Process according to claim 6, wherein the selection of the coded alternating current signal is accomplished by passing the coded alternating current signals through fork-circuits.

8. Process according to claim 6 comprising the additional step of compensating the signal to be transmitted to said subscriber by the signal received from said subscriber.

9. The process according to claim 6 wherein the selection of the coded alternating current signal is accomplished by passing the coded alternating current signals through resistor means.

10. Process for the coded transmission of several information signals via a common transmission path in which

each information signal is transformed into a code alternating current of a predetermined frequency, wherein the code alternating currents contain code elements which consist of at least one half wave of the code alternating current;

two code alternating currents are added with a mutual phase shift of 90°

, in order to produce a sum alternating current with a predetermined phase state;

the sum alternating current is combined with a further coded alternating current, which is shifted in phase by 90°

with respect to that of the sum alternating current; and

the combined coded alternating current is transmitted;

wherein the production of a code alternating current includes the following steps;

(a) producing a clocksignal with a period which is equal to the duration of a predetermined incremental change in the half-wave duration, (b) applying the clock-signal to a counter with controllable start-time and counting the clock-signal by means of the counter, (c) selectively sampling output signals from the counter to selectively determine the duration of the running half-wave of the alternating current, (d) applying the sampled output signals to a bi-stable switch-means which delivers a square-wave signal having axis crossings corresponding to the arrival of successive sampled signals from the counter and half-cycle durations determined in accordance with the selection of the sampling signals, (e) resetting the counter by the counter-output signal, (f) controlling the amplitude of the half-waves of the square-wave signal depending upon the information to be transmitted, and (g) transforming the square-wave voltage produced from the switch means into a sinusoidal signal.

11. Process for the transmission of information in four information channels, wherein the information is presented by means of an essentially sinusoidal first, second, third and fourth code alternating currents, which have a predetermined frequency and consist of a sequence of oscillation periods which at any given time contain two successive half-waves with predetermined duration and opposite polarity, wherein the half-waves are capable of assuming at least two different discrete amplitude values which form a code which represents the information of the pertinent channel, said process comprising the following steps:

(a) adding the first and the second code alternating currents with a mutual phase shift of 90 degrees for the production of a first sum code alternating current, (b) adding the third and the fourth code alternating currents with a mutual phase shift of 90 degrees for the production of a second sum code alternating current, (c) adding the first and second sum code alternating currents with a mutual phase shift of 90 degrees for the production of a combined sum code alternating current, and (d) transmitting the combined sum code alternating current.

12. Process according to claim 11, wherein the first and second information channels contain a luminance portion of a color-TV signal, wherein the third information channel contains a first color signal and wherein the fourth information channel contains a second color signal as a tint signal.

13. Process according to claim 11, wherein the transmitted sum code alternating currents are sampled at points which are displaced in phase 45 degrees before and after a zero-crossing of the sum code alternating current, which points are ascertained by counting of measurement impulses.

14. Process according to claim 11, wherein the decoding of the code alternating currents is accomplished by:

(a) producing comparison signals representative of every possible code-combination corresponding to the half-waves of distinguishable amplitudes, and (b) subtractively mixing the transmitted combined sum code alternating current with each one of the comparison signals, the existence of a particular code combination being recognized by the subtractive cancelation of the corresponding comparison signal.

15. Process for the coded transmission of a color-TV signal, which contains a luminance component, first and second color components and additional signal components, comprising the following steps:

(a) producing a first code alternating current which has a predetermined frequency and consists of a sequence of oscillation periods which contain at any given time two half-waves of opposite polarity, (b) producing a second code alternating current which has the predetermined frequency and consists of a sequence of oscillation periods which contain at any given time two half-waves of opposite polarity, wherein the amplitudes of the half-waves of said first and second code alternating currents represent the luminance component, (c) producing a third code alternating current which has the predetermined frequency and consists of a sequence of periods which at any given time contain two half-waves of opposite polarity, wherein the half-waves of the third code alternating current are capable of taking on at least two discrete, differing amplitude values which form a digital code which represents at least the first color signal component, (d) producing a fourth code alternating current which has the predetermined frequency and consists of periods which at any given time contain two half-waves of opposite polarity which form a digital code which represents at least the second color component, (e) adding the first and second code alternating currents with a mutual phase shift of 90 degrees in order to produce a first sum code alternating current, (f) adding said third and fourth code alternating currents with a mutual phase shift of 90 degrees in order to produce a second sum alternating current, (g) adding the first and second sum code alternating currents with a mutual phase shift of 90 degrees in order to produce a combined code alternating current, and (h) transmitting the combined code alternating current.

16. Process according to claim 15, wherein the transmitted sum code alternating currents are sampled at points which are displaced in phase 45 degrees before and after a zero-crossing of the sum code alternating current, which points are ascertained by counting of measurement impulses.

17. Process according to claim 15, wherein the decoding of the code alternating currents is accomplished by:

(a) producing comparison signals representative of every possible code-combination corresponding to the half-waves of distinguishable amplitudes, and (b) subtractively mixing the transmitted combined sum code alternating current with each one of the comparison signals, the existence of a particular code combination being recognized by the subtractive cancelation of the corresponding comparison signal.

18. Process for the coded transmission of several information signals via a common transmission path in which

each information signal is transformed into a code alternating current of a predetermined frequency, wherein the code alternating currents contain code elements which consist of at least one half wave of the code alternating current;

two code alternating currents are added with a mutual phase shift of 90°

, in order to produce a sum alternating current with a predetermined phase state;

the sum alternating current is combined with a further coded alternating current, which is shifted in phase by 90°

with respect to that of the sum alternating current; and

the combined coded alternating current is transmitted;

wherein the code elements which are formed by half-waves of a predetermined first polarity of a first of said alternating currents represent a first stereo-signal and the code elements which are formed by half-waves of a second polarity of said first alternating current opposed to the first polarity represent a second stereosignal.

19. Process for the simultaneous transmission of first information from a first to a second station and of second information from the second to the first station over a single transmission path, comprising the following steps:

carrying out the following steps in said first station;

(a) producing an essentially sinusoidal first signal having a predetermined frequency as well as a predetermined phase and consists of a sequence of oscillation periods each of which at any given time contains two half-waves following one another with predetermined duration and opposite polarity, wherein said half-waves are able to take on at least two different discrete amplitude values which set forth a code representing said first information, and wherein all amplitude values are greater than zero, (b) transmitting said first signal from said first station to said second station over said single transmission path,

carrying out the following steps in said second station;

(a) obtaining a second sinusoidal oscillation having said predetermined frequency and phase by passing the transmitted first signal through a fork circuit, (termination circuit) (b) decoding the transmitted first signal in order to retrieve said first information, (c) feeding said second sinusoidal oscillation as an input signal into a 90-degree-phase shifter, which delivers an output signal, phase shifted by 90 degrees with respect to said input signal and thus shifting the phase of said second sinusoidal oscillation by 90 degrees, (d) producing an essentially sinusoidal second signal out of the phase-shifted second oscillation, wherein said second signal has the phase of the phase-shifted second oscillation and the predetermined frequency and consists of a sequence of oscillation-periods, each of which at any given time contains two halfwaves following on each other with predetermined duration and opposite polarities, wherein said half-waves are able to take on at least two different discrete amplitudes, which set forth a code representing said second information, and wherein all amplitude values are greater than zero, (e) transmitting said second signal over said single transmission path to said first station, and

carrying out the following step in said first station;

decoding the transmitted second signal in order to retrieve said second information.

20. Process according to claim 19 comprising the following additional step in said second station:

compensating the signal to be transmitted by the signal received.

21. Process for transmission of information in three information-channels, wherein the information is presented by means of an essentially sinusoidal first, second and third code alternating currents, which have a predetermined frequency and consist of a sequence of oscillation periods which at any given time contain two successive half-waves with predetermined duration and opposite polarities, wherein the half-waves are capable of taking on at least two different discrete amplitude values which form a code which represents the information of the pertinent channel, said process comprising the following steps:

(a) adding the first and the second code alternating currents with a mutual phase shift of 90 degrees for the production of a sum code alternating current, (b) adding the sum code alternating current and the third code alternating current with a mutual phase shift of 90 degrees for the production of a combined code alternating current, and (c) transmitting the combined code alternating current.