Master/slave converter system

• US 4,606,072 A
• Filed: 10/08/1985
• Issued: 08/12/1986
• Est. Priority Date: 06/10/1983
• Status: Expired due to Term

• Current Assignee: General Instrument Corporation (CommScope Holding Company, Inc.)
• Original Assignee: Tocom, Inc. (CommScope Holding Company, Inc.)
• Inventors: Martin, Thomas F., Chenoweth, John S., Storey, Robert W., Schoenenberger, Carl F.
• Primary Examiner(s): Ng, Jin F.
• Application Number:
  US06/786,144
• Time in Patent Office: 308 Days
• Field of Search: 455/2-6, 455/53, 455/56, 375/7, 375/8, 375/36, 358/84, 358/86, 358/114
• US Class Current: 725/151
• CPC Class Codes: H04M 11/00 Telephonic communication systems specially adapted for combination with other electrical systems
• CPC Class Codes: H04N 7/10 Adaptations for transmission by electrical cable H04N7/12 takes precedence
• CPC Class Codes: H04N 7/173 with two-way working, e.g. subscriber sending a programme selection signal

Abstract

A multiple converter system is provided for a remote user in a cable communications system. The converters at the user location are linked together via a splitter. One converter operates as a master converter transmitting a master control signal to the other converters, designated as slave converters. The slave converters are actuated only upon reception of the master control signal. The master control signal is interrupted by the master converter only when it transmits data upstream to the central office or when one of the slave converters is required to transmit data. A slave converter notifies the master converter of the need to transmit data by a slave signal. A transmitter unit is automatically activated for transmitting data upstream upon the absence of the master signal on the bus.

Claims

1. In a communication system having a central office and at least one remote user location having a plurality of converters a data transmitter, and a splitter connected between said transmitter and said converters a process comprising:

transmitting a master control signal from a master converter at the remote user location to at least one slave converter at the same remote user location via said splitter;

activating the slave converter only in response to reception of the master control signal;

receiving a command signal from the central office for transmission of data in the master converter to the central office;

terminating transmission of the master control signal at the remote user locations;

transmitting the data from the master converter to the central office utilizing the data transmitter; and

resuming transmission of the master control signal to the slave converters at the remote user location.

2. The process of claim 1 wherein the data transmitter is activated only upon interruption of reception of the master control signal.

3. In a communications system having a transmitter at a central office for transmitting data signals over a communications link to a user'"'"'s location where the data signals are received and tuned for use thereat, the combination comprising:

a master converter capable of tuning the data signals at the user'"'"'s location having supervisory means for generating a master control signal,

at least one slave converter capable of tuning the data signals in communication with the master converter having disabling means responsive to the master control signal from the master converter for disabling the slave converter in response to the absence of communication of the master control signal to the slave converter,

splitter means in communication with the master converter and the slave converter for passing the data singals from the central office to the master and slave converters and wherein said master converter and slave converter are connected by the splitter means,

whereby said converters are arranged in an interdependent relationship wherein said master converter is independently capable of tuning the data signals and said slave converter is capable of tuning the data signals only upon communication of said master control signal.

4. The system of claim 3 wherein the master control signal is a low frequency signal and the data signals from the central office are high frequency signals.

5. The system of claim 4 wherein the master control signal comprises a DC offset square wave.

6. The system of claim 4 and further comprising blocking means between the splitter means and the central office for preventing passage of the low frequency master control signal to the central office.

7. The system of claim 3 wherein the communication system is a cable system.

8. The system of claim 3 wherein the communication system is a cable television system and the data signals are R-F television program signals.

9. The system of claim 3 further comprising a transmitting means for transmitting data from the master converter to the central office, said transmitting means being actuable by the absence of communication of the master control signal to the transmitting means from the master converter.

10. The system of claim 3, wherein the master control signal is a low frequency signal, the data signals from the central office are high frequency signals and wherein the master converter and the slave converter each include filter means for separating the high frequency data signals from the low frequency master control signal.

11. In a two-way communication system for transmitting data signals between a central office and a plurality of remote user locations where the data signals are received and tuned for use thereat, the combination comprising:

a master converter at a user'"'"'s location capable of tuning the data signals having supervisory means for generating a master control signal,

at least one slave converter at the user'"'"'s location capable of tuning the data signals in communication with the master converter having actuating means responsive to the master control signal from the master converter for enabling the slave converter only upon reception of the master control signal,

transmitter means in communication with the master and slave converters and upstream therefrom for passing data signals from the master converter and slave converter to the central office,

splitter means in communication with the master converter and the slave converter for passing the data signals from the central office to the master and slave converters wherein the master converter and slave converter are connected by the splitter means,

whereby said converters are arranged in an interdependent relationship wherein said master converter is independently capable of tuning the data signals and the slave converter is enabled only upon communication of said master control signal thereto.

12. The system of claim 11 wherein the transmitter means is deactivated in response to the master control signal.

13. The system of claim 11 wheren the master control signal is a low-frequency repetitive signal and the data singals are high frequency information carrying signals.

14. The system of claim 13 wherein the transmitter means includes circuitry for blocking transmission of the low frequency master signal upstream in the communication system.

15. The system of claim 14 comprising a two-way cable communications system.