Associative memory system

Claim 2

An associative memory system comprising: a matrix of associative memory cells interconnected in columns of bits and rows of words, wherein each cell produces an output signal at a first or a second level depending upon whether or not applied information matches the information stored in the cell and wherein each cell in a row is connected to a common output line to produce a multilevel signal proportional to the number of cells on said output line in which the applied information matches said stored information; input means for applying an unclassified word to all of the columns in said matrix simultaneously; mask means interconnecting said input means and said columns for masking selected bits of said unclassified word; and variable threshold sensing means connected to said common output lines for detecting which of the words in said matrix matches said unclassified word within a predetermined number of allowable mismatches.

Claim 3

An associative memory system as set forth in claim 1 and further comprising: readout means coupled to said variable threshold sensing means for causing only the most nearly matching word to be read out.

Claim 4

An associative memory system as set forth in claim 2 wherein said readout means causes the entire most nearly matching word to be read out.

Claim 5

Apparatus for grouping events in n-dimensional space wherein each event is represented by a n-bit word comprising: a m plurality of n-bit word templates interconnected in a m X n matrix, each template representing the concept of a particular group; each template comprising n associative memory cells, wherein each cell produces an output signal at a first or a second level depending upon whether or not applied information matches the information stored in the cell and wherein each cell in a template is connected to a common output line to produce a multilevel signal proportional to the distance in n-dimensional space between the concept represented by the template and an event; input means for applying the word representing an unclassified event to said matrix; and adjustable threshold sensing means coupled to the output line of each template, said adjustable threshold sensing means detecting, within a predetermined range, the concept closest said unclassified event as represented by a minimum number of mismatches.

Claim 6

Apparatus for grouping events in n-dimensional space wherein each event is represented by a n-bit word comprising: a m plurality of n-bit word templates interconnected in a m X n matrix, each template representing the concept of a particular group; each template comprising n associative memory cells, wherein each cell produces an output signal at a first or a second level depending upon whether or not applied information matches the information stored in the cell and wherein each cell in a template is connected to a common output line to produce a multilevel signal proportional to the distance in n-dimensional space between the concept represented by the template and an event; input means for applying the word representing an unclassified event to said matrix; and adjustable threshold sensing means coupled to the output line of each template, said adjustable threshold sensing means detecting, within a predetermined range, the concept closest said unclassified event as represented by a minimum number of mismatches.

Claim 7

Apparatus for grouping events in n dimensional space as set forth in claim 4 wherein at least one template contains at least one masked bit.

Claim 8

Apparatus for grouping events in n-dimensional space as set forth in claim 4 wherein said adjustable threshold sensing means comprises m threshold sensors coupled one each to said templates for detecting within the space defined by the concept and said predetermined range the proximity of an unclassified event to the concept represented by each template, said threshold sensors being adjustable between zero distance and the outermost boundary of each group.

Claim 9

Apparatus for grouping events in n dimensional space as set forth in claim 6 wherein at least one template contains at least one masked bit for generalizing the concept defined by the template.

Claim 10

Encoding and decoding apparatus comprising: a matrix of associative memory cells interconnected in columns of bits and rows of words, each row of cells containing the coded and decoded versions of message words, each cell producing an output signal at a first or a second level depending upon whether or not an applied bit matches the bit contained in the cell and wherein each cell in a row is connected to a common output line to produce a multilevel output signal proportional to the number of mismatched bits on that output line; input means for applying an input word to said entire matrix simultaneously; mask means, interconnecting said input means and said columns, for masking selected bits of said input word during encoding and not masking any bits during decoding; adjustable threshold sensing means connected to said rows for enablIng said encoding and decoding apparatus to accept a predetermined number of errors, said adjustable threshold sensing means detecting the word in said matrix matching said input word within a predetermined number of bits; and readout means coupled to said adjustable threshold sensing means for causing only the word in said matrix matching within said predetermined number of bits to be read out in its entirety during encoding, and for causing only the uncoded portion of the word matching within said predetermined number of bits to be read out during decoding.

Claim 11

Encoding and decoding apparatus comprising: a matrix of associative memory cells interconnected in columns of bits and rows of words, each row of cells containing the coded and decoded versions of message words, each cell producing an output signal at a first or a second level depending upon whether or not an applied bit matches the bit contained in the cell and wherein each cell in a row is connected to a common output line to produce a multilevel output signal proportional to the number of mismatched bits on that output line; input means for applying an input word to said entire matrix simultaneously; mask means, interconnecting said input means and said columns, for masking selected bits of said input word during encoding and not masking any bits during decoding; adjustable threshold sensing means connected to said rows for enablIng said encoding and decoding apparatus to accept a predetermined number of errors, said adjustable threshold sensing means detecting the word in said matrix matching said input word within a predetermined number of bits; and readout means coupled to said adjustable threshold sensing means for causing only the word in said matrix matching within said predetermined number of bits to be read out in its entirety during encoding, and for causing only the uncoded portion of the word matching within said predetermined number of bits to be read out during decoding.

Claim 12

Encoding and decoding apparatus as set forth in claim 8 wherein said sensing means comprises a plurality of adjustable threshold sensors coupled one each to each word in the matrix, said threshold sensors being adjustable between a zero error state and a predetermined maximum error tolerance state.

Claim 13

Encoding and decoding apparatus as set forth in claim 8 wherein at least one cell in at least one word stores blank information for preventing that bit from contributing to said multilevel signal regardless of the setting of said mask means.