Successive frame digital multiplexer with increased channel capacity

• US 4,477,900 A
• Filed: 06/08/1981
• Issued: 10/16/1984
• Est. Priority Date: 04/30/1980
• Status: Expired due to Fees

• Current Assignee: Broadcom, Inc.
• Original Assignee: Broadcom, Inc.
• Inventors: Gruenberg, Elliot L.
• Primary Examiner(s): Griffin, Robert L.
• Assistant Examiner(s): Chin, Stephen
• Application Number:
  US06/271,231
• Time in Patent Office: 1,226 Days
• Field of Search: 370/105, 370/110.1, 370/112, 370/118, 370/82, 375/109, 375/114, 375/25, 179/15.55 R, 179/15.55 T
• US Class Current: 704/212
• CPC Class Codes: H04J 3/1688 the demands of the users being taken into account after redundancy removal, e.g. by predictive coding, by variable sampling reducing bandwidth of signals in general H04B1/66; in PCM-systems H04B14/046; removal of redundancy in telegraph communication H03M7/30
• CPC Class Codes: H04J 7/00 Multiplex systems in which the amplitudes or durations of the signals in individual channels are characteristic of those channels
• CPC Class Codes: H04M 3/561 by multiplexing
• CPC Class Codes: H04M 3/568 audio processing specific to telephonic conferencing, e.g. spatial distribution, mixing of participants echo suppression in two-way loud-speaking telephone systems H04M9/02; sound field processing per se H04S7/30
• CPC Class Codes: H04Q 11/04 for time-division multiplexing H04Q11/0001 takes precedence

Abstract

A digital multiplexer accommodates a large number of information signal channels per digital transmission channel through use of an improved statistical coding technique and successive frame transmission, the technique being based on channel designation and channel code permatation. The information signals are encoded into transmission code words, the code words are ordered into successive transmission frames and the transmission frames are sent over a communications highway to a remote location.

Claims

1. A digital communications system comprising a plurality of input channels for carrying information signals, means associated with each input channel for serially encoding the information signals into a sequence of multibit digital words, timing means, controlling each of the encoding means, for ordering the bit position of each multibit digital word such that a predetermined bit in each word is presented at different times to outputs of each of the encoding means, first means for converting the multibit digital words from each of the encoding means into multibit digital code words, means for multiplying each bit of each code word with a different analog voltage, means for summing the multiplied different analog voltages, second means for converting the summed analog voltage into transmission code words, means for ordering the transmission code words into a plurality of successive transmission frames and means for transmitting the successive transmission frames over a communications highway to a remote location.

4. A digital communications system in accordance with claim 1, wherein said second converting means converts said summed analog voltages into ternary code words, said second converting means further including means for subjecting selected and different bits of said ternary code words to different amounts of delay.

5. A digital communications system in accordance with claim 4, wherein there is further included means for ordering said delayed ternary code words into a plurality of selective transmission frames and means for transmitting the successive transmission frames over a communications highway to a remote location.

2. A digital communications system comprising a plurality of input channels for carrying information signals, means associated with each input channel for encoding the information signals into a sequence of multibit digital code words, means for multiplying each bit of each code word with a different analog voltage, means for summing the multiplied different analog voltages, means for converting the summed analog voltages into transmission code words, means for ordering the transmission code words into a plurality of successive transmission frames and means for transmitting the successive transmission frames over a communications highway to a remote location.

3. A digital communications system comprising a plurality of input channels for carrying information signals, means associated with each input channel for encoding the information signals into a sequence of multibit digital code words, means for multiplying each bit of each code word with a different analog voltage, means for summing the multiplied different analog voltages, means for converting the summed analog voltages into ternary code words, means for subjecting selected and different bits of the ternary code words to different amounts of delay, means for ordering the delayed ternary code words into a plurality of successive transmission frames and means for transmitting the successive transmission frames over a communications highway to a remote location.

6. A digital communications system comprising, a plurality of input channels for carrying information signals, means associated with each input channel for encoding said information signals into multibit digital words, timing means, controlling each of said encoding means for ordering the bit position of each multibit digital word, means for converting said ordered multibit digital words into multibit transmission code words, each bit of said multibit transmission code words identifying particular information signal carrying input channels, and means for transmitting said multibit transmission code words over a communications highway to a remote location.

7. A digital communications system in accordance with claim 6 wherein said transmitting means includes means for ordering said multibit transmission code words into a plurality of successive transmission frames and means for applying said successive transmission frames to said communications highway.

8. A digital communications system in accordance with claim 6 wherein said converting means includes means for identifying a particular information signal carrying input channel and means for identifying a plurality of input channels simuntaneously carrying information signals.

9. A digital communications system in accordance with claim 7 wherein there is further included means located at said remote location for receiving and converting said successive transmission code words into received multibit channel identification words and means for decoding said received multibit channel identification words into said information signals carried on said plurality of input channels.

10. A digital communications system in accordance with claim 8 wherein said identifying means includes a plurality of AND and OR circuits.

11. A digital communications system in accordance with claim 7 wherein said ordering means includes shift register means for imparting varying amounts of delay to predetermined groups of said bits in said multibit transmission code words and gating means for selectively applying said predetermined groups of bits of said communications highway.

12. A digital communications system comprising, a plurality of input channels for carrying information signals, said information signals varying in amplitude, means associated with each input channel for encoding said varying amplitude information signals into multibit digital words, the frequency of occurrence of selected bits in said multibit digital words being dependent on the amplitude of said information signals, timing means, controlling each of said encoding means for ordering the bit position of each multibit digital word and for minimizing the simultaneous occurrence of said selected bits, means for converting said ordered multibit digital words into multibit transmission code words, said selected bits contained within said multibit transmission code words identifying particular information signal carrying input channels and means for combining said transmission code words into transmission frames and for applying said transmission frames to a communications highway connected to a remote location.

13. A digital communications system in accordance with claim 12 wherein there is further included means for detecting the simultaneous occurrence of a plurality of said selected bits and means responsive to said detecting means for generating a unique transmission code word identifying the simultaneous occurrence of said plurality of selected bits.

14. A digital communications system in accordance with claim 13 wherein there is further included at said remote location means for receiving and converting said transmission code words into received multibit channel identification words and means for decoding said received multibit channel identification words into said varying amplitude information signals carried on said plurality of input channels.

15. A digital communications system in accordance with claim 12, wherein said converting means includes a plurality of AND and OR circuits.

16. A digital communications system in accordance with claim 12, wherein said combining means includes shift register means for imparting varying amounts of delay to predetermined groups of said bits in said multibit transmission code words and gating means for selectively applying said predetermined groups of bits to said communications highway.