Patent EP0089831A2 successfully refreshed from Google Patents.
EP0089831A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Data communications system ensuring redundant message suppression
Assignee: Harris Corp
•
Filing: 1983-03-18
•
Granted: —
•
Expires: 2003-03-18
Abstract
Abstract A data communications system includes a transmitter (100-108) for transmitting messages, each of which include message characters, a verification portion and a message sequence number. The message sequence number for each message differs from the message preceding it. A receiver (110-122) includes means for verifying the accuracy of the received message and for returning to the transmitter a signal which is either an acknowledgement signal, if the message is inaccurately received, or an error signal, if the message is inaccurately received. To prevent the utilization by the receiver of redundantly received messages, which might occur if the acknowledgement signal is incorrectly received atthe transmitter, the receiver includes means (118) for comparing the message sequence number with the message sequence number of the last accurately received message (116) and for storing (126) the message only if the message sequence numbers are different.
Inventors
- 👤 Alan J. Carney
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-26 12:34
CPC Classifications
H; H04; H04L; H04L1/00; H04L1/12; H04L1/16; H04L1/18; H04L2001/125
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
134 words
A method of communication between a data transmitter and a data receiver comprising the steps of: a) transmitting a message from said transmitter to said receiver; b) including a message sequence number within each message transmitted with the message sequence number for different sequentially transmitted messages differing from one another; c) receiving said message at said receiver; d) determining the accuracy of said message received at said receiver; e) acknowledging receipt of each accurately received message by sending an acknowledge signal to said transmitter; . f) retransmitting a message from said transmitter upon failure to receive an acknowledge signal from said receiver; and g) accepting an accurately received message at said receiver only if the message sequence number is different from the message sequence number of the last message accurately received at said receiver.
Claim 2
Independent Claim
134 words
A method of communication between a data transmitter and a data receiver comprising the steps of: a) transmitting a message from said transmitter to said receiver; b) including a message sequence number within each message transmitted with the message sequence number for different sequentially transmitted messages differing from one another; c) receiving said message at said receiver; d) determining the accuracy of said message received at said receiver; e) acknowledging receipt of each accurately received message by sending an acknowledge signal to said transmitter; . f) retransmitting a message from said transmitter upon failure to receive an acknowledge signal from said receiver; and g) accepting an accurately received message at said receiver only if the message sequence number is different from the message sequence number of the last message accurately received at said receiver.
Claim 3
Dependent Claim
53 words
The method as claimed in claim 1 further comprising the steps of: h) acknowledging the receipt of erroneously received messages by sending an error signal to said transmitter; and ; i) retransmitting the last transmitted message from said transmitter including the same message sequence number in response to receipt of an error signal.
Claim 4
Dependent Claim
28 words
The method as claimed in claim 2 further comprising the step of incrementing the message sequence number in said transmitter in response to receipt of an acknowledgement signal.
Claim 5
Dependent Claim
108 words
2 or 3, 4. The method as claimed in claim 1, wherein step g ) comprises the steps of: h) maintaining the message sequence number of the last message accurately received from said transmitter; i) comparing the message sequence number of an accurately received message with the message sequence number of the last accurately received message; j) storing the accurately received message only if its message sequence number is different from the message sequence number of the last accurately received message; and k) storing the message sequence number of a message stored in accordance with step j) as the message sequence number of the last accurately received message.
Claim 6
Dependent Claim
126 words
A data communications system comprising in combination, a transmitter (100-108) for transmitting messages which include message sequence numbers (210) wherein the message sequence number for each message differs from the message sequence number of the message preceding it and the message sequence number of the message succeeding it, and a' receiver (110-122) for discriminating between newly received and previously received data messages comprising means for verifying the accuracy of received data messages, characterized in that said receiver includes means (118) for identifying the message sequence number contained in the received data messages and means (126) for accepting a verified message only if the message sequence number of said verified message is different from the message sequence number of the last verified message accepted by said receiver.
Claim 7
Dependent Claim
126 words
A data communications system comprising in combination, a transmitter (100-108) for transmitting messages which include message sequence numbers (210) wherein the message sequence number for each message differs from the message sequence number of the message preceding it and the message sequence number of the message succeeding it, and a' receiver (110-122) for discriminating between newly received and previously received data messages comprising means for verifying the accuracy of received data messages, characterized in that said receiver includes means (118) for identifying the message sequence number contained in the received data messages and means (126) for accepting a verified message only if the message sequence number of said verified message is different from the message sequence number of the last verified message accepted by said receiver.
Claim 8
Dependent Claim
139 words
The data communications system as claimed in claim 5,wherein messages including a verification portion (208) and a message sequence number (210) are transmitted, and wherein said receiver comprises: decoder means (112) for receiving and decoding said messages to determine the accuracy of receipt and to identify the message sequence numbers of said messages; storage means (llb, 126) for storing accurately received messages and the message sequence number of the last accurately received message; and comparator means (118) connected to said decoder means and said storage means for comparing the message sequence number of an accurately received message with the message sequence number of the last accurately received message and means (128) for activating said storage means to store said accurately received message and its message sequence number if the compared message sequence numbers are not equal to one another.
Claim 9
Dependent Claim
53 words
7 . The system as claimed in claim 6-wherein the receiver comprises message receipt indicating means (120, 122) for returning an acknowledgement signal to said transmitter upon accurate receipt of a message and an error signal upon inaccurate receipt of a message so that erroneously received messages can be retransmitted to said receiver.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
Maintenance schedule is calculated for granted US utility patents.