US3909540A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Data and signaling multiplexing in PCM systems via the framing code
Assignee: Nokia of America Corp
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Filing: 1974-09-03
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Granted: 1975-09-30
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Expires: 1994-09-03
Abstract
Abstract A subsystem is added to an existing PCM system to provide N additional data channels and to increase the number of signaling channels. The subsystem includes a framing code generator to produce a framing code having a data code bit position for each of 6N system frames with certain of the bit positions having a distinctive pattern of code bits to provide frame synchronization for the receiver of the existing system and the receiving portion of the subsystem. The N additional data channels are time multiplexed by timing signals from the frame code generator and then the frame code generator inserts each channel of N time multiplexed channels into a different one of N others of the code bit positions to convey the additional data in the framing code without altering the distinctive pattern of code bits. The framing code generator also provides other timing signals to increase the number of signaling channels. A framing code receiver of the subsystem recovers the additional data channels from the framing code, the additional signaling channels and synchronizes the system and subsystem in response to the distinctive pattern of code bits. The subsystem may be converted to Western Electric D2/D3 compatibility by opening a strap on each of the framing code generator and framing code receiver.
Inventors
- 👤 Thomas Paul Maryscuk
- 👤 Iii Lehman Holson Johnson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 14:02
CPC Classifications
H; H04; H04J; H04J3/00; H04J3/02; H04J3/12; H04J3/06; H04J3/0602; H04J3/0605
Claims Analysis
Total Claims: 28
Claim 1
Independent Claim
295 words
In a pulse code modulation time multiplexed system including a transmitter and receiver, said system having a first given number of data channels and a second given number of signaling channels per frame, a subsystem added to said system to provide at least N additional data channels, where N is an integer greater than one, comprising: N sources of additional data; a transmitter portion including first means coupled to said N sources to time multiplex said additional data of said N sources into N time multiplexed channels; and second means coupled to said first means, said second means producing at least one timing signal coupled to said first means to control the multiplexing of said additional data of said N sources, producing a framing code having a code bit position for each of 6N system frames, certain of said code bit positions having a distinctive pattern of code bits to provide frame synchronization, receiving said N time multiplexed channels from said first means and inserting each channel of said N time multiplexed channels into a different one of N others of said code bit positions to convey said additional data in said framing code without altering said distinctive pattern of code bits; and a receiver portion including third means coupled to said second means to receive said framing code, said third means recovering said N time multiplexed channels from said framing code, producing at least two timing signals and being responsive to said distinctive pattern of code bits to produce a synchronization control signal to synchronize said receiver of said system and said receiving portion; and fourth means coupled to said third means responsive to said recovered N time multiplexed channels and said two timing signals to recover said additional data of said N sources.
Claim 2
Dependent Claim
295 words
In a pulse code modulation time multiplexed system including a transmitter and receiver, said system having a first given number of data channels and a second given number of signaling channels per frame, a subsystem added to said system to provide at least N additional data channels, where N is an integer greater than one, comprising: N sources of additional data; a transmitter portion including first means coupled to said N sources to time multiplex said additional data of said N sources into N time multiplexed channels; and second means coupled to said first means, said second means producing at least one timing signal coupled to said first means to control the multiplexing of said additional data of said N sources, producing a framing code having a code bit position for each of 6N system frames, certain of said code bit positions having a distinctive pattern of code bits to provide frame synchronization, receiving said N time multiplexed channels from said first means and inserting each channel of said N time multiplexed channels into a different one of N others of said code bit positions to convey said additional data in said framing code without altering said distinctive pattern of code bits; and a receiver portion including third means coupled to said second means to receive said framing code, said third means recovering said N time multiplexed channels from said framing code, producing at least two timing signals and being responsive to said distinctive pattern of code bits to produce a synchronization control signal to synchronize said receiver of said system and said receiving portion; and fourth means coupled to said third means responsive to said recovered N time multiplexed channels and said two timing signals to recover said additional data of said N sources.
Claim 3
Dependent Claim
12 words
A subsystem according to claim 1, wherein N is equal to two.
Claim 4
Dependent Claim
28 words
A subsystem according to claim 2, wherein said distinctive pattern of code bits is three successive binary 1 bits in three adjacent ones of said code bit positions.
Claim 5
Dependent Claim
48 words
A subsystem according to claim 1, wherein N is equal to eight, said second means produces three timing signals to control the multiplexing of said additional data of said N sources, and said third means produces four timing signals to recover said additional data of said N sources.
Claim 6
Dependent Claim
46 words
A subsystem according to claim 4, wherein said distinctive pattern of code bits is three successive binary 1 bits in three adjacent ones of said code bit positions within the first 12 of said code bit positions of 48 code bit positions of said framing code.
Claim 7
Dependent Claim
112 words
A subsystem aCcording to claim 1, wherein said third means includes fifth means to produce a local framing code identical to said received framing code, sixth means coupled to said fifth means to compare said received framing code with said local framing code, seventh means coupled to said sixth means to produce an out-of-sync signal when said sixth means detects a given number of errors in a given length of time; and eighth means coupled to said seventh means responsive to said out-of-sync signal to reestablish synchronization by first finding odd numbered ones of said code bit positions of said received framing code and then locating said distinctive pattern of code bits.
Claim 8
Dependent Claim
34 words
A subsystem according to claim 6, wherein N is equal to two, and said distinctive pattern of code bits is three successive binary 1 bits in three adjacent ones of said code bit positions.
Claim 9
Dependent Claim
52 words
A subsystem according to claim 6, wherein N is equal to eight, and said distinctive pattern of code bits is three successive binary 1 bits in three adjacent ones of said code bit positions within the first 12 of said code bit positions of 48 code bit positions of said framing code.
Claim 10
Dependent Claim
54 words
A subsystem according to claim 1, wherein said second means further produces two additional timing signals, and further including at least two signaling multiplexers coupled to said second means, each of said signaling multiplexers responding to both of said two additional timing signals to increase the number of said signaling channels in said system.
Claim 11
Dependent Claim
61 words
A subsystem according to claim 9, wherein said third means further produces a pair of additional timing signals, and further including at least two signaling demultiplexers coupled to said third means, each of said signaling demultiplexers responding to both of said pair of additional timing signals to define channel outputs for said increased number of said signaling channels in said system.
Claim 12
Dependent Claim
191 words
In a pulse code modulation time multiplexed transmitter having a first given number of data channels and a second given number of signaling channels per frame, a subsystem added to said transmitter to provide at least N additional data channels, where N is an integer greater than one, comprising: N sources of additional data; first means coupled to said N sources to time multiplex said additional data of said N sources into N time multiplexed channels; and second means coupled to said first means, said second means producing at least one timing signal coupled to said first means to control the multiplexing of said additional data of said N sources, producing a framing code having a code bit position for each of 6N transmitter frames, certain of said code bit positions having a distinctive pattern of code bits to provide frame synchronization, receiving said N time multiplexed channels from said first means and inserting each channel of said N time multiplexed channels into a different one of N others of said code bit positions to transmit said additional data in said framing code without alterning said distinctive pattern of code bits.
Claim 13
Dependent Claim
191 words
In a pulse code modulation time multiplexed transmitter having a first given number of data channels and a second given number of signaling channels per frame, a subsystem added to said transmitter to provide at least N additional data channels, where N is an integer greater than one, comprising: N sources of additional data; first means coupled to said N sources to time multiplex said additional data of said N sources into N time multiplexed channels; and second means coupled to said first means, said second means producing at least one timing signal coupled to said first means to control the multiplexing of said additional data of said N sources, producing a framing code having a code bit position for each of 6N transmitter frames, certain of said code bit positions having a distinctive pattern of code bits to provide frame synchronization, receiving said N time multiplexed channels from said first means and inserting each channel of said N time multiplexed channels into a different one of N others of said code bit positions to transmit said additional data in said framing code without alterning said distinctive pattern of code bits.
Claim 14
Dependent Claim
12 words
A subsystem according to claim 11, wherein N is equal to two.
Claim 15
Dependent Claim
28 words
A subsystem according to claim 12, wherein said distinctive pattern of code bits is three successive binary 1 bits in three adjacent ones of said code bit positions.
Claim 16
Dependent Claim
32 words
A subsystem according to claim 11, wherein N is equal to eight, and said second means produces three timing signals to control the multiplexing of said additional data of said N sources.
Claim 17
Dependent Claim
46 words
A subsystem according to claim 14, wherein said distinctive pattern of code bits is three successive binary 1 bits in three adjacent ones of said code bit positions within the first 12 of said code bit positions of 48 code bit positions of said framing code.
Claim 18
Dependent Claim
54 words
A subsystem according to claim 11, wherein said second Means further produces two additional timing signals, and further including at least two signaling multiplexers coupled to said second means, each of said signaling multiplexers responding to both of said two additional timing signals to increase the number of said signaling channels in said transmitter.
Claim 19
Dependent Claim
160 words
In a pulse code modulation time multiplexed receiver having a given number of data channels and a second given number of signaling channels per frame, a subsystem added to said receiver responding to a framing code having a code bit position for each of 6N receiver frames, certain of said bit positions having a distinctive pattern of code bits to provide frame synchronization, and N others of said code bit positions conveying N additional data, where N is an integer greater than one, said subsystem comprising: first means to receive said framing code, to recover said N additional data from said framing code, to produce at least two timing signals and to respond to said distinctive pattern of code bits to produce a synchronization control signal to synchronize said receiver and said subsystem; and second means coupled to said first means responsive to said two timing signals and said recovered N additional data to demultiplex said recovered N additional data.
Claim 20
Dependent Claim
160 words
In a pulse code modulation time multiplexed receiver having a given number of data channels and a second given number of signaling channels per frame, a subsystem added to said receiver responding to a framing code having a code bit position for each of 6N receiver frames, certain of said bit positions having a distinctive pattern of code bits to provide frame synchronization, and N others of said code bit positions conveying N additional data, where N is an integer greater than one, said subsystem comprising: first means to receive said framing code, to recover said N additional data from said framing code, to produce at least two timing signals and to respond to said distinctive pattern of code bits to produce a synchronization control signal to synchronize said receiver and said subsystem; and second means coupled to said first means responsive to said two timing signals and said recovered N additional data to demultiplex said recovered N additional data.
Claim 21
Dependent Claim
12 words
A subsystem according to claim 17, wherein N is equal to two.
Claim 22
Dependent Claim
28 words
A subsystem according to claim 18, wherein said distinctive pattern of code bits is three successive binary 1 bits in three adjacent ones of said code bit positions.
Claim 23
Dependent Claim
27 words
A subsystem according to claim 17, wherein N is equal to eight, and said first means produces four timing signals to demultiplex said recovered N additional data.
Claim 24
Dependent Claim
46 words
A subsystem according to claim 20, wherein said distinctive pattern of code bits is three successive binary 1 bits in three adjacent ones of said code bit positions within the first 12 of said code bit positions of 48 code bit positions of said framing code.
Claim 25
Dependent Claim
112 words
A subsystem according to claim 17, wherein said first means includes third means to produce a local framing code identical to said received framing code, fourth means coupled to said third means to compare said received framing code with said local framing code, fifth means coupled to said fourth means to produce an out-of-sync signal when said fourth means detects a given number of errors in a given length of time, and sixth means coupled to said fifth means responsive to said out-of-sync signal to reestablish synchronization by first finding one numbered ones of said code bit positions of said received framing code and then locating said distinctive pattern of code bits.
Claim 26
Dependent Claim
34 words
A subsystem according to claim 22, wherein N is equal to two, and said distinctive pattern of code bits is three successive binary 1 bits in three adjacent ones of said code bit position.
Claim 27
Dependent Claim
52 words
A subsystem according to claim 22, wherein N is equal to eight, and said distinctive pattern of code bits is three successive binary 1 bits in three adjacent ones of said code bit positions within the first 12 of said code bit positions of 48 code bit positions of said framing code.
Claim 28
Dependent Claim
64 words
A subsystem according to claim 22, further including an increased number of signaling channels transmitted to said receiver; and at least two signaling demultiplexers coupled to said first means; and wherein said first means further produces two additional timing signals, said two signaling demultiplexers responding to both of said two additional timing signals to define channel outputs for said increased number of signaling channels.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-09-29 | 1979-03-31 | 1979-09-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-09-29 | 1983-03-31 | 1983-09-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-09-29 | 1987-03-31 | 1987-09-30 | $7700.00 | Window Closed / Lapsed |