Patent US4361895A successfully refreshed from Google Patents.
← Back to Patent Explorer
US4361895A Expired / Lapsed US ⏱️ 0.0 years remaining

Manchester decoder

Assignee: NEW ONTEL Corp A CORP OF DE
•
Filing: 1980-07-28
•
Granted: 1982-11-30
•
Expires: 2000-07-28
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract A decoder for Manchester encoded data. Each mid-bit transition of the Manchester encoded data is detected and used to activate a counter which counts pulses from a local clock having a pulse rate eight times the data bit rate. The sixth pulse thus occurs at a point one-fourth of a data bit interval after the start of the next data bit interval. At that point the Manchester encoded data is sampled. Since the clock utilized to produce the Manchester encoded data is at a logic level zero at the sampling time, the sampled logic level of the Manchester data is the same as the logic level of the original data. The sampled logic level is used to recreate the original data level, and so the recreated pulse waveform is of the same wave shape as the original data pulse waveform but lags the original by one-fourth a data bit interval.

Inventors

  • 👤 Benjamin M. Khoudari

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-05 11:21
CPC Classifications
H; H04; H04L; H04L7/00; H04L7/02; H04L7/033; H04L7/0331; H04L25/00; H04L25/38; H04L25/40; H04L25/49; H04L25/4906

Claims Analysis

Total Claims: 7
Claim 1
Independent Claim 84 words
A method of decoding Manchester encoded data to recreate an original data stream, said method comprising: detecting each mid-bit transition in the Manchester encoded data; commencing at each mid-bit transition time measuring a time interval substantially equal to three-fourths of the data bit interval to determine a sampling point; sampling the Manchester data at each sampling point; and causing the logic level of the recreated data stream to be the same as the logic level of the Manchester encoded data at the sampling point.
Claim 2
Independent Claim 84 words
A method of decoding Manchester encoded data to recreate an original data stream, said method comprising: detecting each mid-bit transition in the Manchester encoded data; commencing at each mid-bit transition time measuring a time interval substantially equal to three-fourths of the data bit interval to determine a sampling point; sampling the Manchester data at each sampling point; and causing the logic level of the recreated data stream to be the same as the logic level of the Manchester encoded data at the sampling point.
Claim 3
Dependent Claim 39 words
A method as claimed in claim 1 in which the time intervals are measured by counting clock pulses from a clock having a pulse rate which is an integral multiple of the bit rate of the original data stream.
Claim 4
Dependent Claim 96 words
Apparatus for decoding Manchester encoded data to recreate an original data stream, said apparatus comprising: a transition detector for detecting each mid-bit transition in the Manchester encoded data; means for measuring a time interval commencing with each mid-bit transition and extending for a time substantially equal to three-fourths the data bit interval to determine a sampling point; means for sampling the Manchester encoded data at each sampling point, and means for generating a data stream having a logic level at each sampling point the same as the Manchester encoded data logic level at the sampling point.
Claim 5
Dependent Claim 96 words
Apparatus for decoding Manchester encoded data to recreate an original data stream, said apparatus comprising: a transition detector for detecting each mid-bit transition in the Manchester encoded data; means for measuring a time interval commencing with each mid-bit transition and extending for a time substantially equal to three-fourths the data bit interval to determine a sampling point; means for sampling the Manchester encoded data at each sampling point, and means for generating a data stream having a logic level at each sampling point the same as the Manchester encoded data logic level at the sampling point.
Claim 6
Dependent Claim 73 words
Apparatus as claimed in claim 3 in which said measuring means comprises a clock having a pulse rate which is an integral multiple of the bit rate of the original data stream and a counter for counting clock pulses from said clock to generate a sampling point signal on generation of a number of pulses indicating passage of three-fourths of a data bit interval since detection of a transition by said transition detector.
Claim 7
Dependent Claim 84 words
Apparatus as claimed in claim 4 in which said transition detector comprises a first flip-flop which is toggled by the first clock pulse from said clock after a transition in the Manchester encoded data, a second flip-flop which is toggled by the second clock pulse from said clock after the transition in the Manchester encoded data, and an exclusive-OR gate having a first input connected to the output of said first flip-flop and a second input connected to the output of said second flip-flop.

References Cited (Backward Citations)

US3402264A Cited
US3980825A Cited
US3967062A Cited
US3967061A Cited
US4112383A Cited
US4146743A Cited
US4080572A Cited
US4242755A Cited
US4124778A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1985-11-29 1986-05-31 1986-11-30 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1989-11-29 1990-05-31 1990-11-30 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1993-11-29 1994-05-31 1994-11-30 $7700.00 Window Closed / Lapsed

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag