Petition for Inter Partes Review of U.S. Patent No. 8,238,412
`
`
`
`UNITED STATES PATENT AND TRADEMARK OFFICE
`
`———————
`
`BEFORE THE PATENT TRIAL AND APPEAL BOARD
`
`———————
`
`
`
`Cisco Systems, Inc.,
`Petitioner
`
`vs.
`
`TQ Delta, LLC
`
`
`
`———————
`
`
`
`PETITION FOR INTER PARTES REVIEW
`
`OF
`
`U.S. PATENT NO. 8,238,412
`
`
`
`
`
`
`
`1
`
`

`

`Petition for Inter Partes Review of U.S. Patent No. 8,238,412
`
`TABLE OF CONTENTS
`
`PETITIONER’S EXHIBIT LIST ........................................................................... 4
`
`I.  MANDATORY NOTICES ............................................................................... 6 
`
`A.  Real Party-in-Interest ................................................................................. 6 
`
`B.  Related Matters .......................................................................................... 6 
`
`C.  Lead and Back-up Counsel and Service Information ............................... 7 
`
`II.  GROUNDS FOR STANDING .......................................................................... 7 
`
`III.  REQUESTED RELIEF ..................................................................................... 8 
`
`IV.  REASONS FOR THE REQUESTED RELIEF ................................................ 8 
`
`A.  Summary of the ’412 Patent ...................................................................... 8 
`
`B.  Prosecution History ................................................................................... 9 
`
`C.  Priority Date ............................................................................................ 10 
`
`D.  Summary of the Petition .......................................................................... 11 
`
`E.  Note Regarding Page Citations ............................................................... 11 
`
`V. 
`
`IDENTIFICATION OF CHALLENGES AND CLAIM
`CONSTRUCTION .......................................................................................... 12 
`
`A.  Challenged Claims ................................................................................... 12 
`
`B.  Statutory Grounds for Challenges ........................................................... 12 
`
`C.  Level of Ordinary Skill in the Art ........................................................... 12 
`
`D.  Claim Construction .................................................................................. 13 
`
`VI.  IDENTIFICATION OF HOW THE CONSTRUED CLAIMS ARE
`UNPATENTABLE .......................................................................................... 15 
`
`2
`
`

`

`Petition for Inter Partes Review of U.S. Patent No. 8,238,412
`
`A.  Summary of the Prior Art ........................................................................ 16 
`
`1. 
`
`2. 
`
`3. 
`
`4. 
`
`Summary of Milbrandt .................................................................... 16 
`
`Summary of Chang ......................................................................... 16 
`
`Summary of Hwang ........................................................................ 17 
`
`Summary of ANSI T1.413 .............................................................. 18 
`
`B.  Reasons to Combine ................................................................................ 18 
`
`1.  Reasons to Combine Milbrandt with Chang ................................... 18 
`
`2.  Reasons to Combine Milbrandt/Chang with Hwang ...................... 23 
`
`3.  Reasons to Combine Milbrandt/Chang/Hwang with ANSI
`T1.413 ............................................................................................. 25 
`
`C.  Claims 9-12, 15-18, and 21 are obvious under 35 U.S.C. § 103(a)
`over Milbrandt in view of Chang, Hwang, and ANSI T1.413 ................ 29 
`
`1.  Claim 9 ............................................................................................ 29 
`
`2.  Claim 11 .......................................................................................... 38 
`
`3.  Claim 15 .......................................................................................... 42 
`
`4.  Claim 16 .......................................................................................... 49 
`
`5.  Claim 17 .......................................................................................... 60 
`
`6.  Claim 18 .......................................................................................... 62 
`
`7.  Claim 21 .......................................................................................... 64 
`
`8.  Claims 10 and 12 ............................................................................. 66 
`
`VII.  CONCLUSION ................................................................................................ 68 
`
`VIII. CERTIFICATE OF WORD COUNT .............................................................. 69 
`
`3
`
`

`

`Petition for Inter Partes Review of U.S. Patent No. 8,238,412
`
`PETITIONER’S EXHIBIT LIST
`
`May 6, 2016
`
`1001 U.S. Patent No. 8,238,412 to Krinsky et al.
`
`1002 Prosecution File History of U.S. 8,432,956
`
`1003 Prosecution File History of U.S. 8,238,412
`
`1004 Prosecution File History of U.S. 7,835,430
`
`1005 Prosecution File History of U.S. 7,570,686
`
`1006 Prosecution File History of U.S. 6,658,052
`
`1007 U.S. Provisional Application No. 60/224,308
`
`1008 U.S. Provisional Application No. 60/174,865
`
`1009 Declaration of Dr. Sayfe Kiaei Under 37 C.F.R. § 1.68
`
`1010 Curriculum Vitae of Dr. Sayfe Kiaei
`
`1011 U.S. Patent No. 6,636,603 to Milbrandt
`
`1012 U.S. Patent No. 6,891,803 to Chang et al.
`
`1013 U.S. Patent No. 6,590,893 to Hwang et al.
`
`1014 ANSI T1.413-1995 Standard
`
`1015 Charles K. Summers, ADSL STANDARDS, IMPLEMENTATION, AND
`ARCHITECTURE (CRC Press 1999) (selected pages)
`
`1016 Walter Goralski, ADSL AND DSL TECHNOLOGIES (McGraw-Hill 1998)
`(selected pages)
`1017 Harry Newton, Newton’s Telecom Dictionary, 16th Ed. (2000)
`(selected pages)
`
`4
`
`

`

`Petition for Inter Partes Review of U.S. Patent No. 8,238,412
`
`1018 Valerie Illingworth and John Daintith, THE FACTS ON FILE
`DICTIONARY OF COMPUTER SCIENCE (Market House Books 2001)
`(selected pages)
`
`1019 Thomas Starr, John M. Cioffi, Peter J. Silverman, Understanding
`Digital Subscriber Line Technology, (Prentice Hall 1999) (selected
`pages)
`
`1020 Andrew S. Tanenbaum, COMPUTER NETWORKS (Prentice Hall 1996)
`(selected pages)
`
`1021 B. P. Lathi, Modern Digital and Analog Communication Systems
`(Oxford University Press 1998) (selected pages)
`
`1022 Behzad Razavi, RF MICROELECTRONICS (Prentice Hall 1997) (selected
`pages)
`
`1023 Declaration of David Bader
`
`
`
`
`
`
`5
`
`

`

`Petition for Inter Partes Review of U.S. Patent No. 8,238,412
`
`I. MANDATORY NOTICES
`
`A. Real Party-in-Interest
`
`The Petitioner and real party in interest is Cisco Systems, Inc.
`
`B. Related Matters
`
`To the best knowledge of the Petitioner, U.S. Patent No. 8,238,412 (“the
`
`’412 Patent”) is involved in the following litigations:
`
`Court Filed
`Number
`1-15-cv-00611 DED
`Jul. 17, 2015
`
`Name
`TQ Delta LLC v. Comcast Cable
`Comms. LLC
`TQ Delta LLC v. CoxCom
`Jul. 17, 2015
`1-15-cv-00612 DED
`TQ Delta LLC v. DIRECTV
`Jul. 17, 2015
`1-15-cv-00613 DED
`TQ Delta LLC v. DISH
`Jul. 17, 2015
`1-15-cv-00614 DED
`TQ Delta LLC v. Time Warner Cable
`Jul. 17, 2015
`1-15-cv-00615 DED
`TQ Delta LLC v Verizon Comms., Inc.
`Jul. 17, 2015
`1-15-cv-00616 DED
`Adtran Inc v. TQ Delta LLC
`Feb. 3, 2015
`1-15-cv-00121 DED
`TQ Delta LLC v. ADTRAN
`Jul. 17, 2014
`1-14-cv-00954 DED
`ADTRAN v. TQ Delta, LLC
`5-14-cv-01381 ALND Jul. 17, 2014
`TQ Delta, LLC v. ZyXEL Comms. Corp. 1-13-cv-02013 DED Dec. 9, 2013
`TQ Delta, LLC v. Pace Americas, LLC
`1-13-cv-01835 DED Nov. 4, 2013
`TQ Delta LLC v. Zhone Techs. Inc.
`1-13-cv-01836 DED Nov. 4, 2013
`
`The ’412 Patent and related U.S. Patent Nos. 8,432,956 (“the’956 Patent”)
`
`and 7,835,430 (“the’430 Patent”) are involved in the following related matters:
`
`Name
`Petition for IPR of the ’430 Patent by
`ARRIS Group, Inc.
`Petition for IPR of the ’956 Patent by
`
`Court Filed
`Number
`IPR2016-00428 PTAB
`Jan. 2, 2016
`
`IPR2016-00429 PTAB
`
`Jan. 3, 2016
`
`6
`
`

`

`Petition for Inter Partes Review of U.S. Patent No. 8,238,412
`
`ARRIS Group, Inc.
`Petition for IPR of the ’412 Patent by
`ARRIS Group, Inc.
`
`Concurrent with the filing of this Petition challenging claims 9-12, 15-18,
`
`IPR2016-00430 PTAB
`
`Jan. 3, 2016
`
`and 21 of the’412 Patent, Petitioner is also filing a Petition challenging claims 1-8,
`
`13, 14, 19, and 20, which refers to the same exhibit list and expert declaration.
`
`Petitioner is also filing Petitions for related ’956 and ’430 Patents.
`
`C. Lead and Back-up Counsel and Service Information
`
`Lead Counsel
`David L. McCombs
`HAYNES AND BOONE, LLP
`2323 Victory Ave. Suite 700
`Dallas, TX 75219
`
`
`214-651-5533
`Phone:
`214-200-0853
`Fax:
`
`david.mccombs.ipr@haynesboone.com
`USPTO Reg. No. 32,271
`
`Back-up Counsel
`Theodore M. Foster
`HAYNES AND BOONE, LLP
`2323 Victory Ave. Suite 700
`Dallas, TX 75219
`Gregory P. Huh
`HAYNES AND BOONE, LLP
`2323 Victory Ave. Suite 700
`Dallas, TX 75219
`
`II. GROUNDS FOR STANDING
`
`
`972-739-8649
`Phone:
`972-692-9156
`Fax:
`
`ipr.theo.foster@haynesboone.com
`USPTO Reg. No. 57,456
`Phone:
`972-739-6939
`Fax:
`
`972-692-9156
`gregory.huh.ipr@haynesboone.com
`USPTO Reg. No. 70,480
`
`Petitioner certifies that the ’412 Patent is available for inter partes review
`
`and that Petitioner is not barred or estopped from requesting inter partes review
`
`challenging the patent claims on the grounds identified in this Petition.
`
`7
`
`

`

`Petition for Inter Partes Review of U.S. Patent No. 8,238,412
`
`III. REQUESTED RELIEF
`
`Petitioner asks the Board to review the accompanying prior art and analysis,
`
`institute a trial for inter partes review of claims 9-12, 15-18, and 21 of the ’412
`
`Patent, and cancel those claims as unpatentable.
`
`IV. REASONS FOR THE REQUESTED RELIEF
`
`As explained below, the concepts described and claimed in the ’412 Patent
`
`were not novel. This Petition and the declaration of Cisco Systems’ expert, Dr.
`
`Sayfe Kiaei, explain where each element is found in the prior art and why the
`
`claims would have been obvious to a person of ordinary skill in the art prior to the
`
`earliest effective priority date.
`
`A.
`
`Summary of the ’412 Patent
`
`The ’412 Patent describes exchanging diagnostic and test information
`
`between transceivers over a digital subscriber line (DSL). Ex. 1001, 1:59-65. This
`
`information includes power level per subchannel information, idle channel noise,
`
`and signal to noise ratio (id., 6:2-12) and is exchanged using multiple carriers with
`
`a higher order quadrature amplitude modulation (QAM) scheme with more than 1
`
`bit per carrier (id., 3:52-56). Ex. 1009, p.12-14.
`
`Fig. 1 of the ’412 Patent illustrates a functional block diagram of a
`
`communication system capable of the claimed techniques.
`
`8
`
`

`

`Petition for Inter Partes Review of U.S. Patent No. 8,238,412
`
`
`
`Ex. 1001, Fig. 1.
`
`Claims 9, 11, 15-18, and 21 are each independent claims. Claim 9 is
`
`generally representative:
`
`9. A non-transitory computer-readable information storage media
`having stored thereon instructions that, if executed, cause a
`transceiver to perform a method comprising:
`transmitting a message, wherein the message comprises one or
`more data variables that represent the test information, wherein
`bits in the message are modulated onto DMT symbols using
`Quadrature Amplitude Modulation (QAM) with more than 1 bit
`per subchannel and wherein at least one data variable of the one
`or more data variables comprises an array representing power
`level per subchannel information.
`Ex. 1001, 9:31-41.
`B.
`Prosecution History
`
`The ’412 Patent was filed on May 13, 2010, with a preliminary amendment
`
`canceling the original claims and presenting new claims 44-64. Ex. 1003, p.808. A
`
`9
`
`

`

`Petition for Inter Partes Review of U.S. Patent No. 8,238,412
`
`second preliminary amendment added new claims 56-66. In the first Office Action,
`
`the Examiner rejected the claims for nonstatutory double patenting over U.S.
`
`Patent Nos. 7,835,430 and 7,889,784. Id., p.89-104. Following a terminal
`
`disclaimer (id. at 73-83), the Examiner issued a Notice of Allowance for claims 44-
`
`64, without providing a statement of reasons for allowance. Id., p.60-66. The ’412
`
`Patent issued on August 7, 2012.
`
`C.
`
`Priority Date
`
`The ’412 Patent claims priority to two provisional applications, but the
`
`claims are not entitled to the benefit of either. Provisional Application No.
`
`60/224,308 was filed on August 10, 2000, and names as inventors Murat Belge,
`
`Michael A. Tzannes, and Halil Padir. Ex. 1007, p.1, 3. None of these individuals is
`
`named as an inventor on the ’412 Patent. Because there is no overlap of
`
`inventorship, the ’412 Patent is not entitled to the benefit of the filing date of the
`
`’308 Application. 35 U.S.C. § 119(e)(1); MPEP 211.01(a).
`
`Provisional Application No. 60/174,865 was filed on January 7, 2000, and
`
`describes “bits that are modulated by using 1 bit per DMT symbol modulation.”
`
`Ex. 1008 at 5. The application, however, does not describe using QAM with more
`
`than 1 bit per subchannel or an array representing frequency domain received idle
`
`channel noise information, as required by the claims of the ’412 Patent.
`
`Accordingly, the ’412 Patent is not entitled to the benefit of the filing date of the
`
`10
`
`

`

`Petition for Inter Partes Review of U.S. Patent No. 8,238,412
`
`’865 Application. 35 U.S.C. § 119(e)(1); MPEP 211.05.
`
`D.
`
`Summary of the Petition
`
`Testing a communication line for its ability to support digital subscriber line
`
`(DSL) services, and exchanging test information, were not new as of the ’412
`
`Patent’s effective filing date in 2001. Specifically, the prior art recognized that a
`
`DSL communication link needed to measure the transmission characteristics of the
`
`telephone line over which it operates. Since DSL is a multicarrier communication
`
`technology, and since the transmission characteristics can vary significantly over
`
`the different carrier frequencies available, the prior art also recognized that the
`
`measurements should include separately measuring the noise and power of each
`
`carrier frequency. DSL standards had also adopted the transmission of data using
`
`quadrature amplitude modulation (QAM) with more than 1 bit per subchannel.
`
`Because the ’412 Patent’s claims use the prior-art communication technology to
`
`exchange information gathered using prior-art line measurements, the claims are
`
`unpatentable and should be canceled.
`
`E. Note Regarding Page Citations
`
`For exhibits that include suitable page numbers in their original publication,
`
`Petitioner’s citations are to the original page numbers and not to the page numbers
`
`added for compliance with 37 CFR 42.63(d)(2)(ii).
`
`11
`
`

`

`Petition for Inter Partes Review of U.S. Patent No. 8,238,412
`
`V.
`
`IDENTIFICATION OF CHALLENGES AND CLAIM
`CONSTRUCTION
`
`A. Challenged Claims
`
`Claims 9-12, 15-18, and 21 of the ’412 Patent are challenged in this Petition.
`
`B.
`
`Statutory Grounds for Challenges
`
`Challenge #1: Claims 9-12, 15-18, and 21 are obvious under 35 U.S.C. §
`
`103(a) over U.S. Patent No. 6,636,603 to Milbrandt (“Milbrandt,” Ex. 1011) in
`
`view of U.S. Patent No. 6,891,803 to Chang et al. (“Chang,” Ex. 1012), U.S. Patent
`
`No. 6,590,893 to Hwang et al. (“Hwang,” Ex. 1013), and American National
`
`Standards Institute (ANSI) T1.413-1995 Standard, entitled “Network and
`
`Customer Installation Interfaces—Asymmetric Digital Subscriber Line (ADSL)
`
`Metallic Interface,” (“ANSI T1.413,” Ex. 1014). Ex. 1009, p.104.
`
`Milbrandt was filed on July 30, 1999, Chang was filed December 18, 1998,
`
`and Hwang was filed on April 7, 1999. Thus, each of these is prior art at least
`
`under § 102(e). ANSI T1.413 was approved on August 18, 1995, published shortly
`
`thereafter, and is prior art under § 102(b). Ex. 1009, pp. 33-34; Ex. 1023, ¶ 2. Also,
`
`the additional evidentiary references relied upon by Dr. Kiaei in his declaration
`
`were also publicly available. See, e.g., Ex. 1023, ¶¶ 3-9.
`
`C. Level of Ordinary Skill in the Art
`
`The level of ordinary skill in the art may be reflected by the prior art of
`
`record. See Okajima v. Bourdeau, 261 F.3d 1350, 1355 (Fed. Cir. 2001); In re
`
`12
`
`

`

`Petition for Inter Partes Review of U.S. Patent No. 8,238,412
`
`GPAC Inc., 57 F.3d 1573, 1579 (Fed. Cir. 1995). Here, the person of ordinary skill
`
`in the art is someone knowledgeable concerning multicarrier communications.
`
`That person would have (i) a Master’s degree in Electrical and/or Computer
`
`Engineering, or equivalent training, and (ii) approximately five years of experience
`
`working in multicarrier telecommunications. Ex. 1009, p.15-16. Lack of work
`
`experience can be remedied by additional education, and vice versa. Id. at 16.
`
`D. Claim Construction1
`
`This Petition analyzes the claims consistent with their broadest reasonable
`
`interpretation in light of the specification. See 37 C.F.R. § 42.100(b). Claim terms
`
`not discussed below are to be given their broadest reasonable interpretation, as
`
`understood by one of ordinary skill in the art consistent with the disclosure. In re
`
`Translogic Tech., Inc., 504 F.3d 1249, 1257 (Fed. Cir. 2007).
`
`“frequency domain received idle channel noise information” (claims 16-
`
`18): The ’412 Patent specification does not use this term, but does discuss an
`
`“average idle channel noise.” Ex. 1001, 4:17. The specification also mentions a
`
`“frequency domain received idle channel” as part of a bulk enumeration of kinds of
`
`test information. Id., 6:2-13. A person of ordinary skill in the art would have
`
`understood that “frequency domain” generally refers to analysis of a signal on a
`
`1 It is noted that there are other relevant terms that are discussed by Dr. Kiaei in his
`
`declaration. See Ex. 1009, p.25-29.
`
`13
`
`

`

`Petition for Inter Partes Review of U.S. Patent No. 8,238,412
`
`frequency basis. See, e.g., Ex. 1017, p.377; Ex. 1009 p. 19. A person of ordinary
`
`skill in the art would have understood that “idle channel noise” refer to noise that
`
`exists in a communication path when no signals are present. Ex. 1017, p.438; Ex.
`
`1009 p. 19. This same concept is sometimes also referred to as “background
`
`noise.” See Ex. 1017, p.97; Ex. 1009 p. 19. Consistent with the specification’s
`
`description and for the purposes of this proceeding, a POSITA would have
`
`understood that the broadest reasonable interpretation of this phrase includes
`
`“information about the background noise present in each of a plurality of
`
`frequency subchannels when the subchannels are not in use.” Ex. 1009, p. 20.
`
` “during Showtime” (claim 15): The term “during Showtime” is described in
`
`the specification as “during showtime, e.g., the normal steady state transmission
`
`mode, or the like.” Ex. 1001, 3:32-34. Showtime is a term of art used in ADSL
`
`ANSI-T1.413 communication standards. Ex. 1009, p.22. After a communication
`
`link is tested, “each modem notifies its peer that it is ready to enter normal
`
`communications, known in the standard as ‘showtime.’” Ex. 1019, p.379; see also
`
`Ex. 1014, p.108. Consistent with the specification’s description and with its special
`
`meaning as a term of art, and for the purposes of this proceeding, a POSITA would
`
`have understood that the broadest reasonable interpretation of “during Showtime”
`
`includes “during normal communications of an ANSI T1.413-compliant device.”
`
`Ex. 1009, p.22.
`
`14
`
`

`

`Petition for Inter Partes Review of U.S. Patent No. 8,238,412
`
`“array” (claims 9-12, 15-18, 21): The ’412 Patent uses this term according
`
`to its ordinary meaning. See Ex. 1001, 4:42-45. Contemporary dictionaries define
`
`“array” to mean an “ordered collection of identical structures” (Ex. 1017, p.71) or
`
`a “collection of data items . . . [that are] arranged in a particular order or pattern
`
`and are all of the same type.” Ex. 1018, p. 9. Consistent with the dictionary
`
`definitions and for the purposes of this proceeding, a POSITA would have
`
`understood that the broadest reasonable interpretation of “array” includes “an
`
`ordered collection of multiple data items of the same type.” Ex. 1009, p. 22-23.
`
`“transceiver” (claims 9-12, 15-18, 21): The word “transceiver” is a
`
`combination of the words transmitter and receiver. Ex. 1009, p.24. The ’412 Patent
`
`“refer[s] to the transceivers generically as modems.” Ex. 1001, 1:59-65. Consistent
`
`with the specification, and for the purposes of this proceeding, a POSITA would
`
`have understood that the broadest reasonable interpretation of “transceiver”
`
`includes “a device, such as a modem, with a transmitter and receiver.” Ex. 1009,
`
`p.24-25; Ex. 1017, p.913.
`
`VI.
`
`IDENTIFICATION OF HOW THE CONSTRUED CLAIMS ARE
`UNPATENTABLE
`
`Claims 9-12, 15-18, and 21 of the ’412 Patent are obvious under 35 U.S.C. §
`
`103(a) over Milbrandt, Chang, Hwang, and ANSI T1.413. Ex. 1009, p.104.
`
`15
`
`

`

`Petition for Inter Partes Review of U.S. Patent No. 8,238,412
`
`A.
`
`Summary of the Prior Art
`
`1.
`
`Summary of Milbrandt
`
`Milbrandt describes technology that allows a digital subscriber line (DSL)
`
`service provider to test the telephone lines used to deliver service to its customers.
`
`Milbrandt’s system collects measurements of “line noise” and other characteristics
`
`using devices located at the customers’ premises. Ex. 1011, Abstract. The noise
`
`measurements and other information are transmitted from the customers’ premises
`
`to the service provider’s central office over the same telephone lines used to
`
`provide DSL service. Id., 11:38-53. Milbrandt describes using the collected
`
`measurements for various purposes, including determining a transmit power level
`
`for the modems providing DSL services and estimating the data rate capacity of the
`
`subscriber lines. Id., Abstract, 3:17-24, 10:18-24; Ex. 1009, p.30.
`
`Milbrandt further describes how DSL services can provide for high speed
`
`data transmission and Internet access. Ex. 1011, 1:30-39. The communication
`
`components in Milbrandt’s network use “ADSL [asymmetric DSL] techniques that
`
`comply with ANSI Standard T1.413, such as discrete multi tone (DMT)
`
`modulation” to transmit and receive messages. Id., 9:33-34; Ex. 1009, p.31.
`
`2.
`
`Summary of Chang
`
`Like Milbrandt, Chang is directed to testing digital telecommunications
`
`networks such as ADSL. Ex. 1012, 2:54-55. In particular, Chang describes
`
`16
`
`

`

`Petition for Inter Partes Review of U.S. Patent No. 8,238,412
`
`measuring “background noise” across a frequency spectrum by terminating the line
`
`with a characteristic impedance, thereby ensuring that no signals are being
`
`transmitted. Id., 2:59-60, 12:69-12, 12:15-18. Further, Chang describes that it was
`
`well known to use memory such as “ROM,” “PROM,” “EPROM,” and “FLASH”
`
`for storing executable instructions to cause an ADSL modem to perform various
`
`steps during operation. Id., 7:31-56. Thus, Chang discloses a way to measure
`
`background noise and also provides additional details about memory and
`
`executable software that can be utilized in ADSL modems, such as the ADSL
`
`modems described in Milbrandt. Ex. 1009 p. 31-32.
`
`3.
`
`Summary of Hwang
`
`Hwang similarly describes “digital subscriber line communication schemes
`
`capable of utilizing twisted pair wiring from an office or other terminal node of a
`
`telephone network to the subscriber premises.” Id., 2:23-27. Like Milbrandt,
`
`Hwang employs ADSL techniques, and Hwang explains that ADSL uses DMT
`
`technology to divide the available frequency range into 256 distinct carriers, or
`
`tones. Ex. 1013, 3:3-5, 4:58-59; Ex. 1011, 9:31-34. Within each carrier, data is
`
`encoded using quadrature amplitude modulation (QAM) signals. Ex. 1013, 3:1-3.
`
`These techniques provide “effective high-speed data communications over twisted
`
`pair wiring between customer premises and corresponding network-side units . . .
`
`at a central office of the telephone network.” Id., 3:15-19; Ex. 1009, p.32-33
`
`17
`
`

`

`Petition for Inter Partes Review of U.S. Patent No. 8,238,412
`
`4.
`
`Summary of ANSI T1.413
`
`ANSI T1.413 defines the standard electrical characteristics and signals used
`
`in ADSL communications. Ex. 1014, Abstract. It also specifies the minimum
`
`requirements for equipment implementing ADSL. Id.; Ex. 1009, p.34. Included in
`
`these standards is the encoding of data into discrete multitone (DMT) symbols. Ex.
`
`1014, p.23-34. Within each DMT subchannel, an ADSL transmitter encodes a
`
`variable number of bits of data using a constellation encoder. Id., p.43-45. The
`
`constellation encoder of ANSI T1.413 performs quadrature amplitude modulation
`
`(QAM). Ex. 1009, p.34; Ex. 1016, p.188.
`
`B. Reasons to Combine
`
`1.
`
`Reasons to Combine Milbrandt with Chang
`
`Milbrandt describes techniques for measuring operational characteristics,
`
`such as noise information via DSL, including ADSL. Ex. 1011, 8:53-65, 9:31-34.
`
`Milbrandt describes collecting noise information during operation. Id., 12:58-62.
`
`Specifically, Milbrandt teaches sampling a time domain signal communicated by
`
`the central office to a modem at the subscriber premises. Ex. 1011, 12:58-13:3; Ex.
`
`1009, p. 35.
`
`Those of skill in the art would have recognized, however, that it is also
`
`important to measure and evaluate the noise present on the subscriber when the
`
`subchannel is not in operation, since these measurements represent system noise
`
`18
`
`

`

`Petition for Inter Partes Review of U.S. Patent No. 8,238,412
`
`not associated with signals transmitted on the channel. Ex. 1009, p. 35. Skilled
`
`artisans understood that “noise” in a communication system generally refers to any
`
`unwanted signals introduced into the telephone line. Ex. 1017, p. 613. System
`
`noise can come from a variety of sources. Examples include thermal noise, which
`
`is caused by the random motion of electrons in the wires that make up the
`
`subscriber line. Ex. 1020, p. 109. Cross talk is the inductive coupling of signals
`
`between adjacent wires. Id. Impulse noise is a power spike and can be caused by
`
`events such as making or breaking electrical connections to the line. Id. Those of
`
`skill in the art would recognize that all of these common noise sources are
`
`independent of the data signals transmitted on a subscriber line, and therefore, they
`
`are most readily and directly measured when there are no data signals on the line.
`
`Ex. 1009, p. 34.
`
`Chang similarly evaluates DSL communications, including determining
`
`operational characteristics such as noise information, and more specifically
`
`“background noise” when no data is being transmitted. Ex. 1012, 1:6-8, 2:59-61. In
`
`Chang, “[b]ackground noise measures the noise characteristics on the wire pair
`
`over a frequency band of interest . . . for background noise measurement . . . .” Id.,
`
`12:59-66.
`
`A person of ordinary skill in the art working with Milbrandt’s system would
`
`have recognized the advantages of measuring background noise using Chang’s
`
`19
`
`

`

`Petition for Inter Partes Review of U.S. Patent No. 8,238,412
`
`technique for assessing interactions. Ex. 1009, p. 36. For example, when the
`
`system of Milbrandt updates the transmit power level for a device on one telephone
`
`line, the impact on adjacent idle telephone lines within a binder group can be
`
`monitored using Chang’s approach. Id., pp. 36-37. Those of skill in the art would
`
`have understood that raising the transmit power level on a telephone line can
`
`improve service quality by delivering a stronger signal to the far end. Id., p. 37.
`
`With a stronger signal, a denser modulation scheme can be employed, allowing
`
`more bits to be encoded onto the DMT subcarriers, and thus faster data
`
`communication speeds to be provided. Id.
`
`It would have been obvious to a person of ordinary skill in the art to
`
`combine the teachings of Chang with those of Milbrandt, for the purpose of
`
`assessing interactions from other sources, including thermal effect, inductive
`
`coupling, and power spikes. Ex. 1009, p.37. A person of ordinary skill would have
`
`understood that assessing the background noise would allow for taking appropriate
`
`remedial measures to minimize system interactions. Id., pp. 37-38. For example,
`
`remedial measures could include adjusting the gains for a particular
`
`communications channel to minimize inductive coupling and including devices to
`
`dampen power spikes. Id., p.38. A person of ordinary skill would have understood
`
`that taking appropriate remedial measures to address system noise would maximize
`
`throughput and reliability, improve service to customers, and make the system as
`
`20
`
`

`

`Petition for Inter Partes Review of U.S. Patent No. 8,238,412
`
`whole commercially desirable in the marketplace. Id.
`
`In short, the combination of Milbrandt and Chang is nothing more than
`
`applying the Chang’s known technique (i.e., measuring background noise in a DSL
`
`system) to the DSL system of Milbrandt, to yield predictable results (e.g.,
`
`assessing system interactions, taking remedial measures, maximizing throughput
`
`and reliability, improving service to customers, and making the system as whole
`
`commercially desirable in the marketplace.) Ex. 1009, p.38.
`
`Further, combining Milbrandt and Chang is nothing more than combining
`
`prior art elements (i.e., Chang’s background noise test circuitry and measurement
`
`approach to Milbrandt’s system) according to known methods to yield predictable
`
`results (e.g., assessing system interactions, taking remedial measures, maximizing
`
`throughput and reliability, improving service to customers, and making the system
`
`as whole commercially desirable in the marketplace). Ex. 1009, pp.38-39.
`
`Chang also provides additional details about ADSL services, beyond those
`
`expressly disclosed in Milbrandt, by explaining that the modem can be
`
`implemented with a processor and memory, such “as RAM, a ROM, a PROM, an
`
`EPROM, a FLASH, registers or other similar devices. Memory 412 can be used to
`
`store the program codes of data or both.” Id., 7:31-46; Ex. 1009, p. 39.
`
`A person of ordinary skill in the art working with the technology of
`
`Milbrandt would have found it obvious to integrate the techniques taught by
`
`21
`
`

`

`Petition for Inter Partes Review of U.S. Patent No. 8,238,412
`
`Chang—which describes additional modem hardware/software implementation
`
`details for the purpose of obtaining a more complete understanding. Ex. 1009,
`
`p.39. In doing so, it would have been obvious to a person of ordinary skill in the art
`
`at the time to combine the teachings of Chang with those of Milbrandt, for the
`
`purpose of allowing Milbrandt’s modems to include executable instructions on
`
`non-transitory memory to perform various communication protocol steps during
`
`operation. Id., pp. 39-40. Using ROM, PROM, EPROM, and FLASH for storing
`
`executable instructions (as Chang teaches), was well suited and desirable for use in
`
`Milbrandt’s modems because the information in the memory is retained when the
`
`modem is powered down thus obviating the need to reload the memory with the
`
`instructions on power up, thereby expediting the time to power up. Id. Indeed, it
`
`was commonplace and well known to use any one of ROM, PROM, EPROM, and
`
`FLASH for storing executable instructions in production modems. Id.
`
`In short, combining Milbrandt and Chang is nothing more than combining
`
`prior art elements (i.e., Chang’s teachings of using non-transitory memory for
`
`storing executable instructions to cause an ADSL modem to perform various steps
`
`during operation and Milbrandt’s modems) according to known methods to yield
`
`predictable results (e.g., allow Milbrandt’s modems to perform the steps required
`
`by various communications protocols and also allow for the executable instructions
`
`for performing such steps to be retained when powering down and minimize the
`
`22
`
`

`

`Petition for Inter Partes Review of U.S. Patent No. 8,238,412
`
`powering up time). Ex. 1009, p.40; See, e.g., Dystar Textilfarben GmbH & Co.
`
`Deutschland KG v. C.H. Patrick, 464 F.3d 1356, 1368, (Fed. Cir. 2006) (holding
`
`that motivation exists “when the ‘improvement’ is technology-independent and the
`
`combination of references results in a product or process that is more desirable, for
`
`example because it is stronger, cheaper, cleaner, faster, lighter, smaller, more
`
`durable, or more efficient. Because the desire to enhance commercial opportunities
`
`by improving a product or process is universal.”).
`
`Notably, Petitioner’s combination permits, but does not require, physical
`
`incorporation of elements, the combined tea