Method and circuit arrangement for transmitting binary data trains

• US 5,623,518 A
• Filed: 04/16/1993
• Issued: 04/22/1997
• Est. Priority Date: 04/23/1992
• Status: Expired due to Term

• Current Assignee: Hani-Prolectronh AG
• Original Assignee: Hani-Prolectronh AG
• Inventors: Pfiffner, Peter
• Primary Examiner(s): TSE, YOUNG TOI
• Application Number:
  US08/047,193
• Time in Patent Office: 1,467 Days
• Field of Search: 375/222-223, 375/238, 375/257, 375/258, 375/272, 375/303, 375/334, 375/239, 375/278, 375/285, 375/296, 375/346, 375/348, 370/8-10, 341/52, 341/55, 341/73, 341/53, 329/300, 329/312, 329/313, 332/100, 332/109, 332/115, 332/112
• US Class Current: 375/278
• CPC Class Codes: H04L 27/24 Half-wave signalling systems

Abstract

A method and apparatus for transmitting binary data trains of 0 and 1 data bits, or combinations of these data bits over a communications network. The data bits are converted into pulses whose polarity changes from pulse to pulse, so as to enable an optimal exploitation of the transmission channel with a low error rate. The pulses generated by an apparatus of the present invention have a signal shape that produces a minimum inter-symbol interference. Processing and evaluation of the transmitted pulses are performed by a processor, so that a minimal error rate is attainable even under unfavorable transmission conditions.

Claims

1. A method for transmitting a binary data train of 0 data bits or 1 data bits, comprising the steps of:

generating an encoded baseband signal by converting the binary data train into a plurality of pulses whose polarity changes from one pulse to a next pulse, such that for each 1 data bit a pulse is generated while for each 0 data bit the pulse is returned to zero, or, alternatively, for each 0 data bit a pulse is generated while for each 1 data bit the pulse is returned to zero;

shaping the pulses prior to transmission so as to minimize an occurrence of an inter-symbol interference and interfering harmonics; and

transmitting the shaded pulses over a communication channel to a receiving station;

the receiving station comprising the step of;

converting the transmitted shaped pulses into the original binary data train of 0 data bits or 1 data bits with the aid of a synchronized clock signal.

2. The method of claim 1, wherein:

the step of converting the transmitted shaped pulses into the original binary data train comprises the step of synchronizing clock generator after a predetermined number of data bits, and wherein at least one synchronizing pulse at a time is transmitted, by which the clock generator is synchronized.

3. The method of claim 1, wherein:

the step of transmitting pulses comprises converting a sequence of data words into corresponding pulse width modulated pulses and subsequently into one output pulse that is transmitted.

4. The method of claim 3, wherein:

the step of converting the sequence of data words into corresponding pulse width modulated pulses comprises converting each transmitted output pulse into a sequence of correspondingly pulse width modulated pulses and subsequently into a corresponding sequence of data words; and

examining the sequence of data words to determine what kind of data bit or data bit combination is contained in the transmitted pulses.

5. The method of claim 1, wherein:

the step of converting the pulses comprises converting each transmitted output pulse into a sequence of correspondingly pulse width modulated pulses and subsequently into a corresponding sequence of data words; and

examining the sequence of data words to determine what kind of data bit or data bit combination is contained in the transmitted pulses.

6. The method of claim 1, wherein:

the step of transmitting pulses to the receiving station comprises transmitting pulses over a radio network.

7. The method of claim 1, wherein:

the step of transmitting pulses to the receiving station comprises transmitting pulses over a radio network having a carrier frequency that is frequency modulated in accordance with a signal shape and amplitude of the transmitted pulses.

8. The method of claim 1, wherein:

the step of transmitting pulses to the receiving station comprises transmitting pulses over a radio network having a carrier frequency that is phase modulated in accordance with a signal shape and amplitude of the transmitted pulses.

9. An apparatus in which a binary data train of 0 data bits or 1 data bits or combinations of 0 and 1 data bits is transferred over a communications network with further data equipment devices, comprising:

a processor that converts the binary data train into a plurality of pulses whose polarity changes from one pulse to a next pulse, said processor comprising;

a digital signal processor;

a counter that is interfaced to said digital signal processor;

a pulse width modulator that is interfaced with said counter; and

a pulse width demodulator that receives a signal from said pulse width modulator;

means for transmitting pulses representing one of 0 data bits, 1 data bits, and combinations of 0 and 1 data bits, to a receiving station over the communications network, said combinations of data bits being provided such that said pulses have different amplitudes and are transmitted for at least two of the bit combinations represented as 11, 10, 01 and 00; and

means for converting the transmitted pulses at said receiving station into their original data bits or data bit combinations.

10. An apparatus in which a binary data train of 0 and 1 data bits is transferred over a communications network with further data equipment devices, comprising:

a data bus;

a processor connected to said data bus;

a counter that counts data received from said processor;

a pulse width modulator that transmits data received from said counter;

means for coupling said pulse width modulator to said communications network; and

a controller that controls said processor and said counter.

11. The apparatus of claim 10, wherein:

said means for coupling comprises a transformer.

12. The apparatus of claim 10, wherein:

said means for coupling comprises a pulse width demodulator.

13. The apparatus of claim 10, further comprising:

an optical coupler that is located between said pulse width modulator and said means for coupling.

14. The apparatus of claim 10, further comprising:

means for receiving data from a second further equipment device; and

a second counter that accepts said data received by said means for receiving, said second counter producing a signal that is supplied to said processor.

15. The apparatus of claim 14, wherein:

said means for receiving comprises a second transformer.

16. The apparatus of claim 14, wherein:

said means for receiving comprises a second pulse width modulator.

17. The apparatus of claim 16, further comprising:

a second optical coupler that is located between said second pulse width modulator and said second counter.

18. The apparatus of claim 17, further comprising:

a third optical coupler that is located between said second pulse width modulator and said controller.

19. The apparatus of claim 10, further comprising:

means for receiving data from a second further equipment device; and

means for switching said counter between said means for receiving and said pulse width modulator.

20. The apparatus of claim 19, wherein:

said means for receiving comprises a second pulse width modulator.

21. The apparatus of claim 10, wherein:

said communications network comprises a radio relay.

22. The apparatus of claim 21, wherein:

said radio relay has at least one frequency-modulatable carrier frequency channel.

23. The apparatus of claim 21, wherein:

said radio relay has at least one phase-modulatable carrier frequency channel.

24. A method for transmitting a binary data train of 0 data bits or 1 data bits, comprising the steps of:

generating an encoded baseband-signal by converting the binary data train into a plurality of pulses whose polarity changes from one pulse to a next pulse;

rearranging the 0 data bits and the 1 data bits in such a way that a data train of dual-bit-units containing 11 or 00, dual-bit-units containing 10 or 01 and single-bit-units containing 0 or 1 are formed;

selecting single-bit-units in accordance with one of the following conditions;

(a) single-bit-units containing 0 are selected for rearrangement when dual-bit-units containing 11 are selected, and

(b) single-bit-units containing 1 are selected for rearrangement when dual-bit-units containing 00 are selected;

assigning pulses of different amplitudes to the dual-bit-units of a selected set, where for each dual-bit-unit a corresponding pulse is generated while for each single-bit-unit the pulse is returned to zero;

shaping the pulses prior to transmission so as to minimize the occurrence of an inter-symbol interference and interfering harmonics; and

transmitting the shaped pulses over a communication channel to a receiving station;

the receiving station comprising the step of;

converting the transmitted shaped pulses into the original binary data train of 0 data bits or 1 data bits with the aid of a synchronized clock signal.

25. The method of claim 24, wherein the step of converting the transmitted shaped pulses into the original binary data train comprises the step of synchronizing a clock generator after a predetermined number of data bits, and wherein at least one synchronizing pulse at a time is transmitted, by which the clock generator is synchronized.

26. The method of claim 24, wherein the transmitting step comprises transmitting the shaped pulses over a radio network.

27. The method of claim 26, wherein the step of transmitting the shaped pulses comprises transmitting shaped pulses over the radio network having a carrier frequency that is frequency modulated in accordance with a signal shape and amplitude of the transmitted shaped pulses.

28. The method of claim 26, wherein the step of transmitting the shaped pulses comprises transmitting shaped pulses over the radio network having a carrier frequency that is phase modulated in accordance with a signal shape and amplitude of the transmitted shaped pulses.