PTAB Delivers Win for Apple in IPR on CDMA Patent

In IPR 2018-01472, brought by Apple Inc., HTC Corporation, HTC America, Inc., and ZTE (USA) Inc. (Apple), the Patent Trial and Appeal Board (PTAB) last week determined all challenged claims of INVT SPE LLC’s (INVT) Patent No. 6,466,563 to be unpatentable as obvious.

The ‘563 patent is titled “CDMA [Code Division Multiple Access] Mobile Station and CDMA Transmission Method” and was issued on October 15, 2002. The patent describes an addition of burst data to the end of a transmission “allow[ing] synchronization with the base station apparatus to be maintained,” thus “making it possible to restart communication immediately.” The transmission interval control circuit also “controls the transmission interval of burst data to N times one slot (N: a natural number) at the end of transmission” to conserve power consumption.

Claim Construction

When addressing claim construction, there was a dispute as to whether or not the patent had expired; if it had not, Apple argued that the claims should be given their “broadest reasonable construction in light of the specification.” However, the PTAB pointed out that the patent had expired prior to the filing of the petition, warranting the “ordinary and customary meaning, as would be understood by a person of ordinary skill in the art at the time of the invention” standard for claim construction (Phillips v. AWH Corp).

“Nevertheless, as would have been understood by a person of ordinary skill in the art, the below claim constructions would have been the same under both the broadest reasonable construction and the standard under Phillips,” said the PTAB.

The Petitioner’s declarant, Dr. Singer, testified that a POSITA “would have been a person having a Bachelor’s degree in electrical engineering or the equivalent plus three years of experience working with digital communication systems… or a Master’s degree in electrical engineering[.]” The Patent Owner declarant, Dr. Vojcic, proposed a similar POSITA, but added particular experience with “cellular radio communication systems.” The PTAB rejected this stipulation and adopted Apple’s proposal of experience with “digital communication systems or in network engineering[.]”

Obviousness Over Nakamura in Light of Okumura

Apple asserted that claims 1-3,5,6,12,13,15, and 16 are unpatentable due to obviousness over Nakamura in view of Okumura.

Nakamura “discloses controlling ‘radio channel transmission . . . so that only signal portions for the necessary signals are transmitted without transmitting any other signal portions when there is no transmission signal to be transmitted.” ‘ The signal transmission of signals is continued to maintain the radio channel “without causing an out-of-synchronization state at a receiving side.”

The Okumura article, titled “A Transmission Experiment of Coherent Multicode DS-CDMA Mobile Radio Access” discloses a “number of technical features including, . . . pilot-signal synchronous detection, traffic-adaptive transmit power control (TPC), . . . ” which when paired become burst data described in claims 1, 5, 10, 12, and 15 of the ‘563 patent.

Apple asserted that it would have been obvious to a POSITA “to modify Nakamura such that its necessary signal includes both pilot symbols and TPC symbols in accordance with the teachings of Okumura.” INVT did not dispute Apple’s analysis of the limitations. The PTAB thus concluded that Apple persuasively demonstrated that Nakamura, in combination with Okumura, teaches inter alia “generating burst frames comprising pilot symbols and transmission power control symbols and no transmission data when there are no transmission data to be transmitted,” as recited in the claims.

According to Apple, Nakamura stated “the signal format formation forms the signal format by thinning a prescribed number of necessary signals[,]” which is also outlined in the ‘563 patent. INVT argued that Nakamura’s figure “fails to demonstrate the required plurality (‘burst frames’ and ‘intervals’) and cyclicality (‘every N slots’) because [the figure] is limited to one time period.” The PTAB favored Apple’s position because the combined figures in Nakamura outlined a cyclical nature of the necessary signals.

Motivation to Combine

Apple said that, although pilot symbols and TPC symbols were disclosed in separate embodiments, “[a] POSITA would understand that [Nakamura’s] teaching directs a skilled artisan to implement the necessary signals with multiple distinct control data, including pilot and TPC symbols,” and “would further recognize that transmitting both pilot and TPC symbols together as control data was well known as evidenced by Okumura.” Apple further argued that a POSITA would recognize the technical benefits of applying the teachings Okumura to a Nakamura system.

INVT disagreed, stating “the Petition relies on unsupported expert testimony, including verbatim recitations by the technical expert of arguments in the Petition,” and that the combination is driven by hindsight. The goal of Nakamura was to minimize transmission signals as much as possible, said INVT. Apple responded by pointing out that “Okumura demonstrates that it was known in the art to transmit both types of control data together” and cited Dr. Vojcic’s deposition in which he conceded a POSITA would know that control signals of different kinds could be combined in various ways with data. The PTAB again found Apple’s position more persuasive, reasoning that INVT’s “argument ignores that Nakamura expressly contemplates and claims combining pilot and TPC symbols.”

The PTAB was also unpersuaded by INVT’s argument for hindsight. It accepted Apple’s contention that Nakamura and Okumura provided sufficient motivation for combining the references in the manner required by the claims. On these facts, the PTAB determined Apple made a persuasive showing that rendered obvious claims 1, 5, 12, and 15.

Obviousness Over Bhagalia and Abe

Apple contended that claims 1-3, 5, 6, 12, 13, 15, 16 were unpatentable under Section103 over Bhagalia in view of Abe.

The Bhagalia publication, titled “Apparatus and Method of Controlling Transmitting Power and Transmit Rate of a Wireless Telecommunication System,” and discloses a “wireless telecommunication system” that “operates in one of three operating modes”: 1) “an acquisition mode;” 2) “a standby mode;” and 3) “a traffic mode.” Each operating mode outlines 20-bit subframes that are “repeated throughout an entire four millisecond frame of information,” which occupies every tenth bit position of a frame.

Abe, titled “Intermittent Transmission Control System,” discloses “[a]n intermittent transmission control system based on a TDMA system which involves a burst transmission” with “a sound presence detector.” It also describes a mode where a reduced burst transmission is sent if no sound is detected for a certain time. This was motivated by a desire to conserve power.

Apple said that Bhagalia discloses both a mobile station apparatus and a base station apparatus for signal transmission, which INVT did not contest. The PTAB concurred, stating that Apple persuasively demonstrated that Bhagalia taught the preamble of the listed claims.

Apple also asserted that a figure in Bhagalia showed pilot symbols and TPC symbols contained in cyclical frames. INVT did not dispute this analysis.

Bhagalia’s ‘standby mode’ was meant to maintain synchronization while lowering power output by transmitting control data, including pilot and TPC symbols, said Apple. A POSITA would have understood this description similar to claim 5 of the ‘563 patent. According to Apple, Abe disclosed cyclical transmission of during the ‘standby mode.’ INVT contended that ‘burst data’ that it described was not disclosed in the publications because they transmitted bits of information over the whole frame. Citing Dr. Vojcic, Bhagalia’s transmission of data was continuous, not periodic bursts of data found in ‘burst frames’ of the ‘563 patent. The PTAB found Apple’s position more persuasive.

Apple added that a POSITA would have reasonably recognized that the transmission disclosed in Bhagalia would need to be conducted a specific rate, which would benefit from a counter approach taught by Abe. INVT disagreed, contending that the systems described in Bhagalia and Abe utilized different control information that might be incompatible if combined. The PTAB favored Apple’s position and determined claims 1, 5, 12, and 15 would have been obvious over Bhagalia and Abe. From the disclosures of Bhagalia and Abe, the PTAB found obvious dependent claims 2, 3, 6, 13, and 16.

Thus, the PTAB found Apple had demonstrated beyond a preponderance of evidence that claims 1-3, 5, 6, 12, 13, 15, and 16 were unpatentable due to obviousness over Nakamura and Okumura, and over Bhagalia and Abe.

Image Source: Deposit Photos
Photography ID: 153617898
Copyright: alexeynovikov