Ex Parte Jorgensen et alDownload PDFPatent Trial and Appeal BoardNov 30, 201714492839 (P.T.A.B. Nov. 30, 2017) Copy Citation 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. 14/492,839 09/22/2014 Lars Jorgensen TI-74296 6490 23494 7590 12/04/2017 TEXAS INSTRUMENTS INCORPORATED P O BOX 655474, M/S 3999 DALLAS, TX 75265 EXAMINER PHUNKULH, BOB A ART UNIT PAPER NUMBER 2412 NOTIFICATION DATE DELIVERY MODE 12/04/2017 ELECTRONIC 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. Notice of the Office communication was sent electronically on above-indicated "Notification Date" to the following e-mail address(es): uspto@ti.com PTOL-90A (Rev. 04/07) UNITED STATES PATENT AND TRADEMARK OFFICE BEFORE THE PATENT TRIAL AND APPEAL BOARD Ex parte LARS JORGENSEN, ZIGANG YANG, and HARDIK PRAKASH GANDHI Appeal 2017-007356 Application 14/492,8391 Technology Center 2400 Before NATHAN A. ENGELS, JAMES W. DEJMEK, and MICHAEL M. BARRY, Administrative Patent Judges. DEJMEK, Administrative Patent Judge. DECISION ON APPEAL Appellants appeal under 35 U.S.C. § 134(a) from a Final Rejection of claims 1-7 and 9-20. The Examiner has withdrawn the rejection of claim 8 and, instead, has objected to claim 8 as being dependent upon a rejected base claim, but has indicated the claim would be allowable if rewritten in independent form. Ans. 11-12. We have jurisdiction over the remaining pending claims under 35 U.S.C. § 6(b). We reverse. 1 Appellants identify Texas Instruments Incorporated as the real party in interest. App. Br. 2. Appeal 2017-007356 Application 14/492,839 STATEMENT OF THE CASE Introduction Appellants’ disclosed and claimed invention is directed to “reducing peak to average power ratio [(PAPR)] in a wireless communication system.” Spec. ^ 3. According to the Specification, by reducing the PAPR, the signal- to-noise ratio (SNR) of the transmitted signal and power efficiency are improved, resulting in a more robust transmission and/or allowing for higher throughput rates than conventional systems. Spec. 13, 16. In a disclosed embodiment, forward error correction (FEC) is applied to data to be transmitted. Spec. 16-18, Fig. 2 (202). Figure 2 is illustrative and is reproduced below. Figure 2 is a block diagram of a wireless transmitter including circuitry to reduce peak to average power. Spec. ^ 8. As shown, FEC-corrected data is provided to PAPR reduction circuitry prior to transmission. Spec. ^ 17-19, Fig. 2 (104). The PAPR circuitry comprises, inter alia, a symbol mapper and interpolator, which generates a representation of the signal to be transmitted. Spec. 19-20, Fig. 2 (204, 214). A peak detector identifies peak signal amplitude values that exceed a predetermined peak amplitude threshold in the representation of the signal generated by the interpolator. 2 Appeal 2017-007356 Application 14/492,839 Spec. If 21, Fig. 2 (216). The peak detector provides an indication to a bit inverter that the peak amplitude threshold has been exceeded. Spec. ^ 21. The bit inverter circuitry (part of the PAPR circuitry) identifies and inverts one or more bits of the FEC-corrected data stream that are associated with the peak signal amplitude. Spec. ^ 24, Fig. 2 (218, 222). Further, regarding the selection of a bit for inversion, the Specification describes: The symbol/bit selection logic 222 may also consider the error correction applied by the forward error correction logic 202 in selection of a bit to invert. Inversion of a bit in the error correction encoded data introduces an error into the transmitted data stream. The symbol/bit selection logic 222 may select a bit to invert that is likely to be detected and corrected by forward error correction logic in the receiver 106. Thus, PAPR reduction circuitry 104 operates in conjunction with the forward error correction applied to the transmitted signal to reduce PAPR without increasing bit or frame error rate. Spec. Tf 27. Claim 1 is illustrative of the subject matter on appeal and is reproduced with the disputed limitation emphasized in italics: 1. A wireless communication system, comprising: a radio frequency wireless transmitter, comprising: signal peak reduction circuitry configured to reduce peak to average power ratio of a signal to be transmitted by reducing amplitude of the signal to be transmitted that is greater than a predetermined amplitude, the signal peak reduction circuitry comprising: a bit inverter configured to: select a bit of a symbol to invert according to a forward error correction code of the signal such that inversion of the bit reduces the amplitude of the signal; and 3 Appeal 2017-007356 Application 14/492,839 invert the selected bit of the symbol. The Examiner’s Rejections 1. Claims 1, 2, 6, 7, 9, and 13-15 stand rejected under 35 U.S.C. § 103(a) as being unpatentable over Kim et al. (US 2006/0120269 Al; June 8, 2006) (“Kim”) and Ma et al. (US 8,189,455 Bl; May 29, 2012) (“Ma”). Final Act. 3-6. 2. Claims 16 and 19 stand rejected under 35 U.S.C. § 103(a) as being unpatentable over Kim and Roh et al. (US 2013/0185617 Al; July 18, 2013) (“Roh”). Final Act. 6-8. 3. Claims 3, 4, 10, and 11 stand rejected under 35 U.S.C. § 103(a) as being unpatentable over Kim, Ma, and McCallister et al. (US 2007/0254592 Al; Nov. 1, 2007) (“McCallister”). Final Act. 8-9. 4. Claims 5 and 12 stand rejected under 35 U.S.C. § 103(a) as being unpatentable over Kim, Ma, and Yeon et al. (US 2006/0215780 Al; Sept. 28, 2006) (“Yeon”). Final Act. 9. 5. Claim 17 stands rejected under 35 U.S.C. § 103(a) as being unpatentable over Kim, Roh, and McCallister. Final Act. 10. 6. Claim 18 stands rejected under 35 U.S.C. § 103(a) as being unpatentable over Kim, Roh, and Yeon.2 Final Act. 10-11. 2 The heading statement for this rejection inadvertently identifies Kim, Roh, and McCallister. Final Act. 10. The body of the rejection, however, makes clear the Examiner relies on the combined teachings of Kim, Roh, and Yeon. Final Act. 11. Appellants have not alleged prejudice as a result of Examiner’s typographical error. Accordingly, we find such error to be harmless. 4 Appeal 2017-007356 Application 14/492,839 7. Claim 20 stands rejected under 35 U.S.C. § 103(a) as being unpatentable over Kim, Roh, and Van Zelst et al. (US 2013/0322563 Al; Dec. 5, 2013) (“Van Zelst”). Final Act. 11-12. Issue on Appeal3 Did the Examiner err in finding the combination of Kim and either Ma or Roh teaches or suggests reducing the amplitude of a signal to be transmitted by “select[ing] a bit of a symbol to invert according to a forward error correction code of the signal,” as recited in claim 1, and commensurately recited in independent claims 9 and 16? ANALYSIS4 Claims 1—7 and 9 15 Appellants assert the Examiner erred in finding the proposed combination of Kim and Ma teaches or suggests selecting a bit of FEC- corrected data to invert according to an FEC code of the signal, as set forth in independent claims 1 and 9. App. Br. 6-10; Reply Br. 1-3. In particular, Appellants argue although Kim describes a bit inverter in the disclosed transmitter line-up, there is no teaching—either in Kim or as modified by 3 We only address this issue, which is dispositive. We do not address additional issues raised by Appellants’ arguments. 4 Throughout this Decision, we have considered the Appeal Brief, filed November 14, 2016 (“App. Br.”); the Reply Brief, filed April 11, 2017 (“Reply Br.”); the Examiner’s Answer, mailed February 13, 2017 (“Ans.”); the Examiner’s second Examiner’s Answer, mailed March 7, 2017 (“Second Ans.”); and the Final Office Action, mailed June 15, 2016 (“Final Act.”), from which this Appeal is taken. Of note, the second Examiner’s Answer is identical to the original Examiner’s Answer except for the annotated date of the Appeal Brief. Second Ans. 1. 5 Appeal 2017-007356 Application 14/492,839 Ma—that the selection of a bit for inversion is done according to an FEC code of the signal. App. Br. 10. Instead, Appellants contend the Examiner’s proposed combination describes the selection of a bit for inversion in a signal that includes FEC coding, but fails to teach or suggest basing the selection according to the FEC code. App. Br. 10. Kim describes a transmitter in an OFDM (Orthogonal Frequency Division Multiplexing) system and, more particularly, for improving the peak-to-average power ratio (PAPR) of the system. Kim 3. Figure 1 of Kim is illustrative and is reproduced below. Figure 1 of Kim illustrates a block diagram of a transmitter line-up in an OFDM system for improving PAPR. Kim ^ 41. As shown, CRC Adder (100) adds a cyclic redundancy check bit to user input data. Kim 42 43. Additionally, Bit Scrambler (101) performs bit scrambling of the input data; a Channel Encoder (102) encodes the data; Interleaver (103) interleaves the data and Bit Inverter (104) “performs bit inversion of a predetermined bit.” Kim 44-53. “[B]it inversion of a random or predetermined bit of the interleaved data [is performed] by an exclusive AND operation with the mask bit input from the controller 107.” Kim 53. Kim further describes that the Controller (107) estimates the PAPR of the output signal from the IFFT 6 Appeal 2017-007356 Application 14/492,839 (inverse fast Fourier transform) Unit (106) and varies a mask bit of the OFDM symbol to transmit to the Bit Inverter (104) when the PAPR is greater than the predetermined threshold value. Kim ^[ 60-61. The Examiner notes that Kim does not disclose forward error correction in the transmitter and instead relies on Ma for this teaching. Final Act. 3 (citing Ma, Abstract, col. 3,1. 64-col. 4,1. 15). In particular, the Examiner finds Ma teaches a transmitter for reducing PAPR in an OFDMA (orthogonal frequency division multiple access) system that uses an FEC- coded signal. Ans. 13 (citing Ma, col. 2,11. 24-29, 56-67). The Examiner concludes “providing [an] FEC signal to the PAPR transmitter [of Kim] and inverting the bit based on the input FEC signal would have been obvious to one having ordinary skill in the art at the time of invention.” Ans. 13. The Examiner has not provided sufficient persuasive technical reasoning or evidence that the proposed modified transmitter (i.e., the transmitter of Kim modified to use an FEC-encoded signal as taught by Ma) selects a bit for inversion according to forward error correction code of the signal. Rather, in the proposed combination, the Controller (107) of Kim would still estimate the PAPR of the output signal from the IFFT Unit (106) and vary a mask bit of the OFDM symbol to transmit to the Bit Inverter (104) when the PAPR is greater than the predetermined threshold value (see Kim ]fl[ 60-61), except that the signal used to estimate PAPR and that may also have a bit inversion applied contains forward error correction. In other words, the Examiner has not explained how the Controller (107) of Kim is modified to select a bit for inversion, not just on an estimated PAPR, but also according to a forward error correction code of the signal. But cf 7 Appeal 2017-007356 Application 14/492,839 Spec. ^ 27 (describing the selection of a bit for inversion that is likely to be detected by forward error correction logic). For the reasons discussed supra, and based on the record before us, we do not sustain the Examiner’s rejection of independent claim 1. For similar reasons, we do not sustain the Examiner’s rejection of independent claim 9, which recites similar limitations. Further, we do not sustain the Examiner’s rejections of claims 2-7 and 10-15, which depend therefrom. Claims 16—20 Similar to independent claims 1 and 9, independent claim 16 recites a bit inverter configured to select a bit of a symbol to invert according to a forward error correction code of the signal such that inversion of the bit reduces the amplitude of the transmitted signal. In rejecting claim 16, the Examiner finds the combination of Kim and Roh teaches or suggests this limitation. Final Act. 7 (citing Kim 60, 61; Roh, Fig. 4, 24). Similar to the rejection of claim 1, the Examiner finds Kim does not teach, inter alia, forward error correction and relies on Roh to teach forward error correction. Final Act. 7; Ans. 15-16 (citing Roh 22, 24). The Examiner concludes “providing [an] FEC signal and inverting the bit based on input FEC signal [as in Roh] . . . based on symbols in the PAPR transmitter taught by KIM would have been obvious to one having ordinary skill in the art.” Ans. 16 (emphasis omitted). For similar reasons to those discussed with respect to the Examiner’s rejection of claim 1, the Examiner has not provided sufficient technical reasoning or evidence that the selection of a bit for inversion is “according to a forward error correction code of the signal” in the proposed combination 8 Appeal 2017-007356 Application 14/492,839 of Kim’s transmitter with Roh’s forward error correction. See Final Act. 6- 7; Ans. 15-16. For the reasons discussed supra, and based on the record before us, we do not sustain the Examiner’s rejection of independent claim 16. Further, we do not sustain the Examiner’s rejections of claims 17-20, which depend therefrom. DECISION We reverse the Examiner’s decision rejecting claims 1-7 and 9-20. REVERSED 9 Copy with citationCopy as parenthetical citation