US3761818A — Multilevel signal transmission system

Claim 1

Independent Claim 207 words

Apparatus for transmitting and receiving a train a multilevel signals having a given number of levels over a transmission line having input and output terminals, said apparatus comprising: transmission means coupled to the input terminal of the transmission line for applying the train of the multilevel signals to the input terminal of the transmission line; and receiving means coupled to the output terminal of the transmission line, said receiving means including sampling means for sequentially receiving and sampling each of the transmitted multilevel signals of the train at a predetermined sampling rate, level error detection means for detecting a level error between the level of one of the transmitted multilevel signals and that of a corresponding multilevel signal to be transmitted by said transmission means, said level difference detection means including level difference polarity detection means for detecting the polarity of the level difference between the one transmitted multilevel signal and each of other multilevel signals received and sampled before or after the one transmitted multilevel signal in the train, and control means for detecting agreement or disagreement between the polarity of the level error and that of the level difference to control the sampling time of said sampling means in accordance with the agreement or disagreement.

Claim 2

Dependent Claim 207 words

Apparatus for transmitting and receiving a train a multilevel signals having a given number of levels over a transmission line having input and output terminals, said apparatus comprising: transmission means coupled to the input terminal of the transmission line for applying the train of the multilevel signals to the input terminal of the transmission line; and receiving means coupled to the output terminal of the transmission line, said receiving means including sampling means for sequentially receiving and sampling each of the transmitted multilevel signals of the train at a predetermined sampling rate, level error detection means for detecting a level error between the level of one of the transmitted multilevel signals and that of a corresponding multilevel signal to be transmitted by said transmission means, said level difference detection means including level difference polarity detection means for detecting the polarity of the level difference between the one transmitted multilevel signal and each of other multilevel signals received and sampled before or after the one transmitted multilevel signal in the train, and control means for detecting agreement or disagreement between the polarity of the level error and that of the level difference to control the sampling time of said sampling means in accordance with the agreement or disagreement.

Claim 3

Dependent Claim 77 words

Apparatus as claimed in claim 1, wherein said transmission means includes reference means for inserting a reference level signal having a predetermined level in the train of the multilevel signal at a predetermined period, and said sampling means of said receiving means samples the transmitted multilevel signal with the predetermined period of the reference level signal to detect a level error of the sampled reference level signal for controlling the sampling rate of the transmitted multilevel signal.

Claim 4

Dependent Claim 113 words

Apparatus as calimed in claim 1, wherein said transmission means includes: storage means, clock means for generating a first, repetitive clock signal at intervals of T/m, where T is a predetermined interval of time and m is a predetermined integer and for generating a second, repetitive clock signal at an interval of T/(m+1); means responsive to the first clock signal for storing the multilevel signals in said storage means; means responsive to the second clock signal for retrieving from said storage means a train of the multilevel signal, and means for inserting at the time intervals of T the reference level signals into the train of multilevel signals retrieved from said storage means.

Claim 5

Dependent Claim 125 words

Apparatus as claimed in claim 1, wherein each level of the multilevel signals to be transmitted is representative of a binary number of n''s bits, where n is a predetermined integer, said receiving means including decoding means for receiving the transmitted multilevel signal and for providing a binary digit of more than n+1 bits for decoding the binary number corresponding to the level of the transmitted signal, said level error detection means providing a level error between At least one of the levels of the transmitted multilevel signal sampled at the predetermined sampling rate and the correct level of a multilevel signal to be transmitted by comparison with a binary digit of a position less significant than the least significant one of the n''s bits.

Claim 6

Dependent Claim 65 words

Apparatus as claimed in claim 1, wherein each level of the multilevel signal to be transmitted is represented with a binary number of n''s bits, where n is a predetermined integer, said transmission means including means for providing the level of the reference level signal of a selected magnitude corresponding to the transition point of the binary digit of selected position of the n''s bits.

Claim 7

Dependent Claim 46 words

Apparatus as claimed in claim 5, wherein said level error detection means detects the error difference between the level of the transmitted reference level signal and a predetermined level of the multilevel signal to be transmitted with respect to a binary digit of the selected position.

Claim 8

Dependent Claim 98 words

Apparatus as claimed in claim 6, wherein said level error detection means includes decoding means for receiving and decoding the transmitted multilevel signal into a binary number of n''s bits indicative of the level of the transmitted multilevel signal, and means for delaying coupled to said decoding means for delaying the binary digit of the position selected from the decoded binary number of the n''s bits for a predetermined period of time, to thereby provide a signal indicative of the difference in level between the transmitted signal and that signal adjacent in the train to the aforementioned signal.

Claim 9

Dependent Claim 38 words

Apparatus as claimed in claim 7, wherein said delay means delays both the binary digit of a selected position and that digit of a position more significant than the selected binary digit, for the predetermined period of time.

Claim 10

Dependent Claim 44 words

Apparatus as claimed in claim 1 wherein said level error detection means includes an exclusive OR circuit for correlating the level error of the transmitted multilevel signal with the level difference between the transmitted signal and the signal in the train disposed adjacent thereto.

Claim 11

Dependent Claim 43 words

Apparatus as claimed in claim 9, wherein said level error detection means further includes average means for averaging the output signal derived from said exclusive OR circuit for controlling the sampling time of said sampling means dependent upon the averaged output signal therefrom.

Claim 12

Dependent Claim 163 words

Apparatus for transmitting a train of multilevel signals having a given number of levels over a transmission line having input and output terminals, said apparatus comprising: transmission means coupled to the input terminal of the transmission line for applying the train of the multilevel signals to the input terminal of the transmission line; and receiving means coupled to the output terminal of the transmission line, said receiving means including sampling means for sequentially receiving and sampling the transmitted multilevel signals of the train at a predetermined sampling rate, level difference detection means for determining a first level difference between the level of one of the transmitted multilevel signals and its level as established by said transmission means and a second level difference between the level of the one transmitted multilevel signal and the level of another multilevel signal adjacent thereto in the train, and control means for comparing the first and second level differences to adjust the sampling time of said sampling means.

Claim 13

Dependent Claim 163 words

Apparatus for transmitting a train of multilevel signals having a given number of levels over a transmission line having input and output terminals, said apparatus comprising: transmission means coupled to the input terminal of the transmission line for applying the train of the multilevel signals to the input terminal of the transmission line; and receiving means coupled to the output terminal of the transmission line, said receiving means including sampling means for sequentially receiving and sampling the transmitted multilevel signals of the train at a predetermined sampling rate, level difference detection means for determining a first level difference between the level of one of the transmitted multilevel signals and its level as established by said transmission means and a second level difference between the level of the one transmitted multilevel signal and the level of another multilevel signal adjacent thereto in the train, and control means for comparing the first and second level differences to adjust the sampling time of said sampling means.

Annuity Stage	Window Opens	Payment Deadline	Surcharge Period Until	Estimated Fee	Status
3.5 Years (Year 4)	1976-09-24	1977-03-26	1977-09-25	$2000.00	Window Closed / Lapsed
7.5 Years (Year 8)	1980-09-24	1981-03-26	1981-09-25	$3760.00	Window Closed / Lapsed
11.5 Years (Year 12)	1984-09-24	1985-03-26	1985-09-25	$7700.00	Window Closed / Lapsed

Multilevel signal transmission system

Abstract

Inventors

Bibliographic Details

Claims Analysis

References Cited (Backward Citations)

USPTO Annuity & Maintenance Windows

Assigned Categories & Tags

Assign Category Tag