Ex Parte Marsili

Patent Trial and Appeal BoardMay 9, 2013

11090811 (P.T.A.B. May. 9, 2013)

UNITED STATES PATENT AND TRADEMARK OFFICE UNITED STATES DEPARTMENT OF COMMERCE United States Patent and Trademark Office Address: COMMISSIONER FOR PATENTS P.O. Box 1450 Alexandria, Virginia 22313-1450 www.uspto.gov APPLICATION NO. FILING DATE FIRST NAMED INVENTOR ATTORNEY DOCKET NO. CONFIRMATION NO. 11/090,811 03/25/2005 Stefano Marsili I446.138.101 / I0371US 5424 106581 7590 05/10/2013 Dicke, Billig & Czaja, PLLC 100 South Fifth Street, Suite 2250 Minneapolis, MN 55402 EXAMINER MALEK, LEILA ART UNIT PAPER NUMBER 2632 MAIL DATE DELIVERY MODE 05/10/2013 PAPER Please find below and/or attached an Office communication concerning this application or proceeding. The time period for reply, if any, is set in the attached communication. PTOL-90A (Rev. 04/07) UNITED STATES PATENT AND TRADEMARK OFFICE ________________ BEFORE THE PATENT TRIAL AND APPEAL BOARD ________________ Ex parte STEFANO MARSILI ________________ Appeal 2010-009662 Application 11/090,811 Technology Center 2600 ________________ Before JEAN R. HOMERE, JASON V. MORGAN, and TREVOR M. JEFFERSON, Administrative Patent Judges. MORGAN, Administrative Patent Judge. DECISION ON APPEAL Appeal 2010-009662 Application 11/090,811 2 STATEMENT OF THE CASE Introduction This is an appeal under 35 U.S.C. § 134(a) from the Examiner’s Final Rejection of claims 1 – 13 and 15 – 20. Claim 14 is canceled. See App. Br. 3. We have jurisdiction under 35 U.S.C. § 6(b)(1). We reverse. Invention The invention is directed to a device for detecting a useful signal by detecting a periodic signal contained in the useful signal using a correlation unit for correlating the signal with the sign of the signal, taking into consideration a time delay between the signal and the sign of the signal. See Spec. ¶ [0023]. Exemplary Claim (Emphases Added) 1. A device for detecting a useful signal by detecting a periodic signal contained in the useful signal, comprising: an auto correlation unit for autocorrelating a signal, which may contain the periodic signal, with the complex conjugate/sign function of the signal, wherein the complex conjugate/sign function is one of the sign function of the complex conjugate of the signal or the complex conjugate of the sign function of the signal, wherein the complex conjugate/sign function of the signal is delayed in time with respect to the signal, an amplitude estimating unit for estimating the amplitude of the signal, and a decision unit, which receives a signal output by the amplitude estimating unit and a signal output by the autocorrelation unit, for deciding about the presence of the periodic signal. Appeal 2010-009662 Application 11/090,811 3 Rejections The Examiner rejects claims 1 – 13 and 15 – 20 under 35 U.S.C. § 103(a) as being unpatentable over Appellant’s Admitted Prior Art (AAPA) (Spec. ¶¶ [0003] – [0021] and figs. 1 – 7), Hwang (US Pat. App. Pub. No.: 2002/0027953 A1; Mar. 7, 2002), and Usui (US 6,393,077 B1; May 21, 2002). Ans. 3 – 10. ISSUE Did the Examiner err in finding that the combination of AAPA and Hwang teaches or suggests “an auto correlation unit for autocorrelating a signal, which may contain the periodic signal, with the complex conjugate/sign function of the signal,” as recited in claim 1? ANALYSIS The Examiner rejects claim 1 as being unpatentable over AAPA, which teaches signal detection using an auto-correlation unit for auto- correlating a signal with its delayed complex conjugate, Hwang, which is directed to a low-complexity blind equalizer, and Usui, which is directed to a correction detecting device and its method. See Ans. 3 – 5. Specifically, the Examiner finds that AAPA teaches or suggests all of the recitations of claim 1, except: (1) “applying a sign function to the complex conjugate of the signal before applying the results to the multiplier and therefore obtaining a complex conjugate/sign function of the signal,” Ans. 3; and (2) use of an amplitude estimation unit instead of a power estimation unit, see id. at 4. Thus, the Examiner relies on Hwang’s teaching that “in a signal estimator (e.g., a blind equalizer) the need for a complex multiplier is often bypassed by employing a so-called sign algorithm . . . at the output of a complex conjugator” to teach or suggest auto-correlating a signal with its Appeal 2010-009662 Application 11/090,811 4 delayed complex/conjugate. Id. at 4 (citing Hwang ¶¶ [0017], [0032], and [0039]). The Examiner further relies on Usui to teach or suggest use of an amplitude estimation unit. See Ans. 4 – 5. Appellant contends that the Examiner erred because Hwang does not teach or suggest generally replacing “conventional multipliers” with “‘simplified multipliers’ (e.g., signs) in various electronic circuitry.” App. Br. 8. Appellant argues that Hwang’s teachings and suggestions regarding the application of a sign switch are limited “to the calculation of equalizer coefficients.” Id. The Examiner responds that “[a]lthough Hwang’s publication does not relate to the autocorrelation multiplication in auto-correlator, . . . it would have been obvious to one of ordinary skill in the art at the time of invention to use the general teaching of Hwang in auto-correlation multiplication disclosed in the background of invention to reduce the complexity of the multiplier.” Ans. 14. However, we agree with Appellant that general remarks about the usefulness of using a sign function—in the limited context of Hwang’s disclosure—is insufficient by itself to show that it would have been obvious to an artisan of ordinary skill to modify the auto- correlator of AAPA using a sign function as claimed. See App. Br. 10. Appellant may have recognized that applying a sign function has a similar benefit in a periodic signal detection auto-correlation unit, as Examiner contends. See Ans. 14. However, the question of obviousness “is not whether the combination was obvious to the patentee but whether the combination was obvious to a person with ordinary skill in the art.” KSR Int’l Co. v. Teleflex, Inc., 550 U.S. 398, 420 (2007). “[A]ny need or problem known in the field of endeavor at the time of invention and addressed by the Appeal 2010-009662 Application 11/090,811 5 patent can provide a reason for combining the elements in the manner claimed.” Id. However, the Examiner’s findings do not show that there was a need to simplify periodic signal detection auto-correlator multipliers or that auto-correlator multiplier complexity was a problem known in the art at the time of the invention. Hwang itself teaches that multipliers are highly complex structures, but fails to show that such complexity was a known problem in periodic signal detection auto-correlators. See Hwang ¶ [0017]. Hwang merely discusses the use of the sign algorithm in the context of coefficient estimation in an adaptive or blind equalizer. See id. at ¶¶ [0017] and [0032]. The Examiner does not provide sufficient evidence or explanation showing that it would have been obvious to an artisan of ordinary skill to apply adaptive or blind equalization simplification technologies to auto- correlators. In the absence of sufficient findings, we agree with Appellant that the Examiner erred in finding that AAPA and Hwang teaches or suggests “an auto correlation unit for autocorrelating a signal, which may contain the periodic signal, with the complex conjugate/sign function of the signal,” as recited in claim 1. The Examiner does not show that Usui cures this deficiency. Accordingly, we do not sustain the Examiner’s rejection of claim 1, and of claims 2 – 13 and 15 – 20, which are similarly rejected. DECISION We reverse the Examiner’s decision to reject claims 1 – 13 and 15 – 20. REVERSED Vsh