In re Iwahashi (888 F.2d 1370, 1989)

RICH, Circuit Judge.

This appeal is from the decision of the United States Patent and Trademark Office (PTO) Board of Patent Appeals and Interferences (board), dated May 24, 1988, adhered to on reconsideration, affirming the examiner’s final rejection of the single claim of applicants’ patent application serial No. 454,022, filed December 28, 1982, entitled “Auto-Correlation Circuit for Use in Pattern Recognition.” The sole ground of rejection is that the subject matter claimed is nonstatutory under 35 U.S.C. § 101 because it is merely a mathematical algorithm. We reverse.

The real party in interest, according to appellants’ brief, is Sharp Kabishiki Kaisha (Sharp Corporation).

The opening sentence of the specification states: “This invention relates to an auto-correlation unit for use in pattern recognition to obtain auto-correlation coefficients as for stored signal samples.” The embodiment more particularly discussed as a species of pattern recognition is voice recognition. The prior art calculation of auto-correlation coefficients is described as being based on a calculation formula involving a multiplication step. The specification states the disadvantage to be as follows:

Those state-of-the-art units for calculation of the auto-correlation coefficients have the disadvantage of requiring expensive multipliers and also complicated circuitry. As a result the auto-correlation unit circuitry within the entire pattern recognition apparatus is proportionately large and auto-correlation calculation demands a greater amount of time during recognition.

The principal object of this invention is to provide an auto-correlation unit for pattern recognition which evaluates auto-correlation coefficients by means of a simple circuitry without the need for an expensive multiplier as well as eliminating the above discussed disadvantages.

Underlying the auto-correlation unit claimed, is a plethora of mathematical demonstration by which the applicants purport to show that the approximated value of the desired coefficient can be obtained without multipliers by obtaining the square of the sum of two of the factors in the equation and calculating the auto-correlation coefficient therefrom according to a stated formula. The specification concludes:

As explained in the foregoing, this invention offers a highly cost effective auto-correlation unit for pattern recognition with simple circuitry without the need to use an expensive multiplier, but which has comparatively high accuracy and can, moreover, calculate auto-correlation coefficients at high speed.

Fig. 1 of the application drawings is described as “a block diagram schematically showing an embodiment of this invention” and appears as follows:

Fig. 2 is described as a block diagram showing in more detail the embodiment of this invention” and appears as follows:

We shall not attempt a description of the electronic circuitry shown by these drawings beyond explaining, for the better understanding of the claim, that the units designated “ROM” and “RAM” are, respectively, a read only memory and a random access memory, terms well understood by those skilled in the art. “CPU” is a central processing unit. In this case, the function of the ROM, 2 or 15, which is a permanent information storage device, is to deliver as output the square of a number fed to it as input. It is the electronic equivalent of a table in which one can look up the square of numbers over a desired range.

We next reproduce the claim on appeal and do so by presenting a copy of the claim as it has been presented in the Solicitor’s brief, to which we have added the letters in brackets designating at [a] the preamble or introductory clause and at [b] through [h] the several means-plus-function and other elements of the combination of elements recited. Under the heading “Drawings” (the Solicitor’s heading was “Fig. 1”) we have copied verbatim the Solicitor’s designations. Element [d], it will be noted, is not in means-plus-function form but specifies a “read only memory” or ROM, as the Solicitor says. Element [f] is an anomolous clause seemingly intended to indicate what data are stored in the ROM. It is not clear that a means for storing anything in the ROM is part of the disclosed “unit” since the application indicates that the squared values are “previously memorized” in the ROM. However that has nothing to do with the sole question before us which is whether the claim as a whole is, in the words of the Solicitor, “directed to nonstat-utory subject matter,” so we shall not comment further on element [f].

Claim Drawings

[a] An auto-correlation unit for providing auto-correlation coefficients for use as feature parameters in pattern recognition for N pieces of sampled input values X„ (n = 0 to N — 1), said unit comprising:

[b] means for extracting N pieces of sample input values Xn from a series of sample values in an input pattern expressed with an accuracy of optional multi-bits; Not shown in Fig. 1; analog to digital converter 11 in Fig. 2.

Tel means for calculating the sum of the sample values X„ and X„ - Z (t = 0 - P, P