Method and apparatus for transmitting and receiving a symbol over pots wiring using a multi-cycle waveform

• US 6,678,321 B1
• Filed: 09/15/1998
• Issued: 01/13/2004
• Est. Priority Date: 09/15/1998
• Status: Expired due to Fees

• Current Assignee: Tut Systems, Inc. (Motorola Solutions, Inc.)
• Original Assignee: Tut Systems, Inc. (Motorola Solutions, Inc.)
• Inventors: Graham, Martin H., Taylor, Matthew, Webber, Harold H. Jr.
• Primary Examiner(s): Pham, Chi
• Assistant Examiner(s): Nguyen, Dung X.
• Application Number:
  US09/153,812
• Time in Patent Office: 1,946 Days
• Field of Search: 375/368, 375/369, 375/239, 375/238, 375/257, 375/259, 375/370, 370/445, 370/473, 370/968, 370/910, 370/267, 370/908, 332/109, 332/112, 340/870.19
• US Class Current: 375/238
• CPC Class Codes: H03K 7/08 Duration or width modulation ; Duty cycle modulation

Abstract

A method of transmitting information over POTS wiring includes transmitting a first delimiter signal, in the form of a multi-cycle waveform having a frequency of approximately 7.5 MHz, over the POTS wiring. A second delimiter signal, also comprising a multi-cycle waveform, is then later propagated over the POTS wiring. The time duration between the respective propagations of the first and second delimiter signals defines a symbol, which encodes information. The time duration is also such that reflections on the carrier medium resulting from the propagation of the first delimiter signal decay to a predetermined level prior to propagation of the second delimiter signal.

Claims

1. A method of transmitting information over a carrier medium within a computer network, the method including:

selecting a time symbol from a group of time symbols, each time symbol within the group of time symbols representing predetermined information;

propagating a first delimiter signal over the carrier medium at a first time; and

propagating a second delimiter signal over the carrier medium at a second time, the time duration between the propagation of the first and second delimiter signals defining the selected time symbol, and the first and second delimiter signals each comprising a multi-cycle waveform having a frequency of greater than 1.1 MHz.

2. The method of claim 1 including propagating each of the first and second delimiter signals as a multi-cycle waveform having a frequency of between 5.5 and 9.5 MHz.

3. The method of claim 2 including propagating each of the first and second delimiter signals as a multi-cycle waveform having a frequency of approximately 7.5 MHz.

4. The method of claim 1 including propagating each of the first and second delimiter signals as a four-cycle waveform.

5. The method of claim 1 wherein the propagating of the first and second delimiter signals each include propagating a multi-cycle square wave through a filter.

6. The method of claim 5 including propagating the multi-cycle square waveform through a Butterworth filter.

7. The method of claim 1 wherein each time symbol within the group of time symbols comprises a fixed-duration portion and a respective encoding portion.

8. The method of claim 1 including the step of propagating the second delimiter signal so that the time duration between the propagation of the first and second delimiter signals is such that reflections on the carrier medium resulting from the propagation of the final delimiter signal have decayed to a predetermined level prior to propagation of the second delimiter signal.

9. The method of claim 8 wherein the propagating of the first and second delimiter signals each comprise propagating a respective delimiter signal over POTS wiring within a structure from a transmitter to a receiver.

10. The method of claim 8 wherein the propagating of the first and second delimiter signals each comprise propagating a respective delimiter signal over UTP wiring within a structure from a transmitter to a receiver.

11. The method of claim 9 wherein the maximum distance between the transmitter and the receiver is less than 500 feet.

12. Apparatus for transmitting information over a carrier medium within a computer network, the apparatus including:

an output to couple the apparatus to the carrier medium; and

an encoder to select a time symbol from a group of time symbols, each time symbol within the group of time symbols representing predetermined information;

a transmitter, coupled to the encoder, to propagate first and second delimiter signals at first and second times, the time duration between the propagation of the first and second delimiter signals defining the selected time symbol, and to construct each of the first and second delimiter signals as a multi-cycle waveform having a frequency of greater than 1.1 MHz.

13. The apparatus of claim 12 wherein the transmitter constructs each of the first and second delimiter signals as a multi-cycle waveform having a frequency of between 5.5 and 9.5 MHz.

14. The apparatus of claim 13 wherein the transmitter constructs each of the first and second delimiter signals as a multi-cycle waveform having a frequency of approximately 7.5 MHz.

15. The apparatus of claim 12 wherein the transmitter constructs each of the first and second delimiter signals as a four-cycle waveform.

16. The apparatus of claim 12 wherein the transmitter includes a filter through a multi-cycle square wave is propagated to generate the first and second delimiter signals.

17. The apparatus of claim 16 wherein the filter is a Butterworth filter.

18. The apparatus of claim 12 wherein each time symbol within the group of time symbols comprises a fixed-duration portion and a respective encoding portion.

19. The apparatus of claim 12 wherein the transmitter propagates the second delimiter signal so that the time duration between the propagation of the first and second delimiter signals is such that reflections on the carrier medium resulting from the propagation of the first delimiter signal have decayed to a predetermined level prior to the propagation of the second delimiter signal.

20. The apparatus of claim 12 wherein the carrier medium comprises POTS wiring within a structure coupled between a transmitter and a receiver.

21. The apparatus of claim 12 wherein the carrier medium comprises UTP wiring within a structure coupled between a transmitter and a receiver.

22. The apparatus of claim 20 wherein the maximum distance between the transmitter and the receiver is less than 500 feet.