The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
May. 09, 1989
Filed:
Nov. 04, 1986
Alan D Clark, Leicester, GB;
Abdullah Hashim, Leicester, GB;
Abstract
An adaptive system for binary data compression incorporating a coding scheme which is simple to implement, which limits codeword length and which can be implemented by software. Data compression is achieved by assigning four bit codes to the eight most frequently occurring characters in the data and eight or nine bit codes to the remaining characters wherein the code assignment is made according to a continuously updated evaluation of character frequency distribution. Run length encoding may be used in conjunction with this technique, to achieve further data compression. For transmission, error control protocols are applied to the compressed data where such protocols may include the use of forward error correcting (FEC) coding and an automatic repeat request (ARQ) system. The data may be transmitted using a burst error control system based on interleaving so that a single error correcting FEC coding can corrects bursts of errors characteristic of a telephone system.