Matter of Application of Richman

• Decision Date: 06 October 1977
• Docket Number: Patent Appeal No. 77-519.
• Citation: 563 F.2d 1026
• Parties: In the Matter of the APPLICATION of Donald RICHMAN.
• Court: U.S. Court of Customs and Patent Appeals (CCPA)

563 F.2d 1026

In the Matter of the APPLICATION of Donald RICHMAN.

Patent Appeal No. 77-519.

United States Court of Customs and Patent Appeals.

October 6, 1977.

Melvin P. Williams, attorney of record, Hartford, Conn., for appellant.

Joseph F. Nakamura, Washington, D. C., for the Commissioner of Patents, Thomas E. Lynch, Washington, D. C., of counsel.

Before MARKEY, Chief Judge, and RICH, BALDWIN, LANE and MILLER, Judges.

MILLER, Judge.

This appeal is from the decision of the Patent and Trademark Office ("PTO") Board of Appeals ("board"), unchanged on reconsideration, sustaining the rejection of claims 1-4¹ under 35 USC 101 for being directed to nonstatutory subject matter. We affirm.

The Invention

The invention involves a method of calculating (according to a mathematical formula) an average boresight correction angle for an airborne, coherent pulse doppler, synthetic aperture, signal processing radar, using actual terrain measurements, and a method of calculating (according to a mathematical formula) the average vertical velocity component of the aircraft carrying the radar, using these same measurements. Appellant describes the invention in terms of the figure below:

The invention is based upon the principle that, although the depression angle (ß1 or ß2) and the range (R1 or R2), and even the absolute distance of the velocity vector (12) of the aircraft to the map cell (16), vary along the flight path, the product of the range and the sine of the depression angle should be constant for the same map cell along a straight line of flight.

In actual practice, however, this product varies when measured from different points. Appellant utilizes this variation in the product of the range and the sine of the depression angle, from the antenna to a given map cell from two separate points (P1, P2) along a straight line of flight of the aircraft, using a specific mathematical formula, to calculate a boresight correction angle. Summation over many cells is employed to calculate an average boresight correction angle (). The average actual vertical (the vertical direction is the normal direction to a plane below which the depression angle is measured—see the dashed lines in the above-copied figure) velocity component Vz and the average actual vertical velocity component Vz, which latter value utilizes the aforementioned average boresight correction angle, are also calculated from summation over many cells, utilizing the depression angles and the ranges in specific mathematical formulae.

Claims 1 and 4 are illustrative:

1. In an airborne coherent pulse doppler synthetic aperture depression angle sensing processing radar, the method of calculating a correction factor d, for measured values of depression angle, ß, comprising:

recording a plurality of signal sets from at least two points in a flight path, each of said signal sets relating to a map cell on a radar map of M cells in which each map cell comprises the intersection of one of K slant range slices with one of J doppler cones, said signal sets comprising a depression angle ß and a slant range Rkj to each kjth map cell in each of the maps, the slant ranges Rkj1 and depression angles ß1 relating to the first map and the slant ranges Rkj2 and depression angles ß2 relating to the second map, said two points being separated along the flight path and therefore in time by a period of time greater than the processing interval for the making of one of said maps; and

calculating a boresight correction angle from the slant range to each cell in the first and second map Rkj1, Rkj2, respectively, and the measured depression angle to each cell in each map ß1, ß2, respectively as follows:

                           S a S b - M S ab
                   =____________________________________
                          M S b2 - (S b)2
                Where a = Rkj2 sin ß - Rkj1 sin ß
                      b = Rkj2 cos ß - Rkj1 cos ß1
                      S = summation across K. J = M cells
                and M = the number of map cells is each map
                

4. In an airborne coherent pulse doppler synthetic aperture depression angle sensing processing radar, the method of calculating the magnitude of the component of velocity perpendicular to the plane from which depression angle is measured, including in said calculation compensation for boresight-induced error in measured values of depression angle, comprising:

recording a plurality of signal sets from at least two points in a flight path, each of said signal sets relating to a map cell on a radar map of M cells in which each map cell comprises the intersection of one of K slant range slices with one of J doppler cones, said signal sets comprising a depression angle ß and a slant range Rkj to each kjth map cell in each of the maps, the slant ranges Rkj1 and depression angles ß1 relating to the first map and the slant ranges Rkj2 and depression angles ß2 relating to the second map, said two points being separated along the flight path and therefore in time by a period of time greater than the processing interval for the making of one of said maps; and

calculating the average value of said velocity component, ß1, from the slant range to each cell in the first and second map Rkj1, Rkj2, respectively, and the measured depression angle to each cell in each map ß1, ß2, respectively, as follows:

                IMAGE
                    Where a= Rkj2 sin & ß - Rkj1 sin ß
                          b = Rkj2 cos ß - Rkj1 cos ß
                       S = summation across K .J = M cells
                

The Board

The majority opinion of the board states that, although the claimed invention is limited to a particular art or technology,

we do not find that reciting an algorithmic process in such a manner as to preempt the use of an arithmetic procedure in a limited field as opposed to in general sic, in a general field, would convert an unpatentable method to patentable subject matter In re Christensen, 478 F.2d 1392, 178 USPQ 35 (Cust. & Pat.App.1973).

The majority opinion answers appellant's argument that the claims include novel steps in addition to the novel calculating step as follows:

Although we find no evidence before us indicating that the step of repeating the aforementioned steps at a later time in the flight path of the aircraft is old, we note that such a step would be required in order to obtain the necessary values of the variables required for solution of the equation set forth. Hence, the repeating step is dictated by the equations to be calculated. Under these circumstances we fail to find any significant distinction between the nature of that which is claimed here, and that which was condemned in Gottschalk v. Benson, 409 U.S. 63, 93 S.Ct. 253, 34 L.Ed.2d 273, 175 USPQ 673 (1972) (hereinafter Benson) and Christensen.

A concurring opinion states that Benson, as explained in Dann v. Johnston, 425 U.S. 219, 96 S.Ct. 1393, 47 L.Ed.2d 692, 189 USPQ 257 (1976), involved no particular art or technology other than pure mathematics; that, therefore, Benson neither compels nor authorizes rejection of claims 1-4 under 35 U.S.C. § 101; but that the calculating step is crucial to establishing unobviousness of the claimed method, and thus Christensen requires affirmance of the section 101 rejection.

OPINION

Both the majority and concurring opinions of the board note that the antecedent steps to obtain data are at least obvious; further, the majority opinion notes that the repeating step is "dictated by the equations to be calculated," while the concurring opinion states that this step is "no more than mere duplication of the prior art practice of map making." Such statements ignore the fact that until the formulae are known, they cannot "dictate" the data-acquiring steps or provide motivation for duplicating the prior art practice of...