MEMORANDUM OPINION
I. INTRODUCTION
The court in this memorandum opinion construes limitations in U.S. Patent Nos. 6,574,267 B1 (“the'267 patent”), as reexamined,
The parties participating in claim construction proceedings have completed consolidated claim construction briefing, and the court held oral argument on March 19,
II. BACKGROUND
A. The Patents-In-Suit and Disputed Limitations
The patents-in-suit are assigned to GBT and list the same two inventors — Emmanuel Kanterakis and KOurosh Parsa. The '267 patent, titled “RACH Ramp-Up Acknowledgement,” originally issued on June 3, 2003 with twenty-nine claims (“the original '267 patent”). Following ex parte reexamination, the United States Patent and Trademark Office (“PTO”) issued a reexamination certificate on December 15, 2009, confirming the patentability of claims 1-12 and 27-29; cancelling claims 13-26; and adding new claims 30-60. The '427 patent, also titled “RACH Ramp-Up Acknowledgement,” is a continuation of the '267 patent and issued on April 15, 2008.
Both patents-in-suit relate generally to wireless cellular networks and teach a method for establishing a communication link between a mobile station, such as a cellular telephone, and a base station. Rather than devoting a communication channel to each mobile station, the system contemplates a channel that allows multiple signals to be sent over the same channel and provides each remote station with random access to the channel (“RACH”). ('267 patent, col. 1:19-23, 1:27-32, 1:55-59) To establish a communication link with a base station, a mobile station must transmit a preamble at a power , level high enough to be detected by the base station. However, if the power is too high, it can cause interference to other mobile stations sharing the same communication channel.
The invention teaches a “ramp-up” process to reduce the risk of interference by ensuring the lowest detectable power level is used while providing fast communication links.. A mobile station seeking to establish a connection with a -base station will transmit preambles at increasing power levels until the signal is detected by a base station. Once a base station detects a preamble, it sends the mobile station an acknowledgment, after which the mobile station begins transmission of data or voice communications.
The parties agree that the patents-in-suit share the same relevant written description and figures and that the claim limitations have the same meaning throughout the patents-in-suit.
B. Prior Litigation Over the '267 Patent
In 2005, GBT filed suit (“the Texas litigation”) in the United States District Court for the Eastern District of Texas (“the Texas court”) alleging infringement of the original '267 patent against Nokia, Inc. (“Nokia”) and Lucent Technologies, Inc. (“Lucent”) (collectively, “the Texas de
As relevant to the instant cases, the parties to the Texas litigation agreed that “preamble” means “a signal used for communication with the base station that is spread before transmission.” However, they disputed the construction of “access preamble.” GBT proposed the construction “a preamble selected for transmission from a set of predefined preambles,” while the Texas defendants argued that an “access preamble” is “an unspread preamble.” (See id. at JA1905) In its claim construction order, the Texas court found that “the surrounding claim language indicates that the patentee has used ‘access preamble’ and ‘preamble’ interchangeably.” (See id.) It reasoned:
Claim 27 provides for “spreading an access preamble selected from a set of predefined preambles; transmitting from the MS transmitter the spread access preamble.” Thus, the “access preamble” is spread before it is transmitted, which is consistent with the notion that a “preamble” is “spread before transmission” as the agreed construction provides.”
(Id.) (citation omitted) (footnote omitted) The Texas court rejected the Texas defendants’ proposed construction, finding that it rested on the unsupported assumption that, before a preamble is “spread,” it is necessarily “un-spread.” Rather, the Texas court found that the claim language and specification “emphasize that the preamble is spread before transmission, but do not explicitly differentiate between ‘spread’ and ‘un-spread’ signals.” (Id. at JA-1906)
On January 29, 2007, the Texas court found the asserted claims of the original '267 patent to be invalid as anticipated under 35 U.S.C. § 102(b) by two prior art publications: (1) the Mobile Station-Base Station Compatibility Standard for Dual-Mode Wideband Spectrum Cellular System IS-95A (“the IS-95A Standard”); and (2) Nokia Telecommunication’s Patent Cooperative Treaty publication No. WO9746041 by Hakkinen, et al. Golden Bridge Tech., Inc. v. Nokia, Inc., Civ. No. 2:05cv151,
III. STANDARD OF REVIEW
Claim construction is a matter of law. Phillips v. AWH Corp.,
IV. THE LIMITATIONS
Claim 27 of the '267 patent (from which asserted claim 51 depends) is illustrative of a method claim reciting the disputed limitations:
27. A method of transferring packet data for a mobile station (MS) with an MS receiver and an MS transmitter, comprising:
receiving at the MS receiver a broadcast common channel from a base station;
determining a plurality of parameters required for transmission of the base station;
spreading an access preamble selected from a set of predefined preambles;
transmitting from the MS transmitter the spread access preamble, at a first discrete power level;
if NO acknowledgement corresponding to the access preamble is detected, transmitting a spread access preamble from the MS transmitter at a second discrete power level higher than the first discrete power level; and upon detecting an acknowledgement corresponding to a transmitted access preamble, ceasing preamble transmission and transmitting the packet data from the MS transmitter.
('267 patent, claim 27) Claim 29 of the '267 patent (from which asserted claim 52 depends) is illustrative of a device claim reciting the disputed limitations:.
29. A code-division-multiple-access (CDMA) wireless handset, comprising: a CDMA transmitter; a CDMA receiver; and a controller coupled to the CDMA receiver for responding to signals received via the CDMA receiver and coupled for controlling the CDMA transmitter, such that in operation the CDMA handset is for performing the following steps: spreading an access preamble selected from a set of predefined preambles; transmitting the spread access preamble, at a first discrete power level to a base station;
if NO acknowledgement corresponding to the access preamble is detected, transmitting a spread access preamble from the MS transmitter at a second discrete power level higher than the first discrete power level; and upon detecting an acknowledgement corresponding to a transmitted access preamble, ceasing preamble transmission and transmitting packet data from the MS transmitter.
(Id., claim 29)
A. “Access Preamble’7“Preamble”
The parties agree that, consistent with the Texas court’s finding, “preamble” and “access preamble” are interchangeable and, thus, should have the same construction.
1. Collateral estoppel
The court first examines, as a threshold matter, what effect the Texas litigation should have on claim construction in the instant cases. Defendants argue that, because the original '267 patent was asserted in the Texas litigation and the Texas court construed “access preamble,” GBT is estopped from relitigating its meaning in this court. Regional circuit law applies to the determination of whether collateral estoppel applies. See Applied Med. Res. Corp. v. U.S. Surgical Corp.,
The court agrees with GBT that collateral estoppel is not applicable because the issue decided by the Texas court is not identical to that being litigated in the instant cases. The '427 patent and the reexamined '267 patent were issued on April 15, 2008 and December 25, 2009, respectively, after the conclusion of the Texas litigation (including the appeal). Neither prosecution history file was of record during that case. That additional prosecution history, before the court in the instant cases, does not necessarily mean that the scope of any disputed limitations changed. However, the court cannot simply ignore new prosecution history that was not of record in the Texas litigation. See Power Integrations, Inc. v. Fairchild Semiconductor Int’l, Inc., Civ. No. 08-309,
2. “Preamble”/“access preamble” is spread before transmission
Although GBT is not estopped from rearguing the construction of “preamble,” there is nothing new in the additional new prosecution history that addresses whether or not a preamble is spread before transmission. The court finds that the construction of “access preamble” and the stipulated construction of “preamble” from the Texas litigation are still applicable insofar as they include spreading prior to transmission.
As the Texas court reasoned, the claim language and specification emphasize that a preamble is spread before transmission. According to the specification and as shown in figure 4, after generation of a preamble and before transmission, a preamble is “spread-spectrum processed by product device 426, with s spreading chip-sequence from spreading-sequence generator 427.” ('267 patent, fig. 4, col. 4:38-51, 5:28-30) Although claim language is not necessarily limited to a particular embodiment, the specification is largely directed to a detailed description of the figures; it does not contemplate any other embodiment regarding generating and transmitting a preamble.
The surrounding claim language is consistent with figure 4 and the specification, and provide that an access preamble is spread before it is transmitted. For example, claims 27 and 29 of the '267 patent, from which asserted claims 51 and 52 depend, provide for “spreading an access preamble selected from a set of predefined preambles; transmitting from the MS transmitter the spread access preamble.” GBT argues that several claims do not recite a “spreading an access preamble” step. ■ (D.I. 212/288 at 6-7) However, GBT’s focus on the absence of that explicit limitation in those claims is unavailing. First, all of the claims that recite a preamble or access preamble also recite either a “spread-spectrum transmitter,”
GBT also asserts that defendants’ proposed construction would render the claim limitation superfluous or ambiguous. (D.I. 208/284 at 21) See Digital-Vending Servs. Int’l, LLC v. Univ. of Phoenix, Inc.,
Finally, the court finds that the prosecution history supports the construction that the specification and claim language require. During prosecution of the original '267 patent, which is upstream from all of the patents-in-suit, the patentee argued, in response to the examiner’s rejection of certain claims:
Another disclosed distinction is that the access preamble here is itself a form of code data (e.g. a signature) that is spread in essentially the same manner as other data.
(D.I. 227/290 at JA289) (emphasis added) Regarding proposed claims 47-49," which later issued as claims 27 and 29, the patentee opined:
Claims 47 and 49 have been amended to more clearly point out certain distinctions over the prior art. Specifically, claims 47 and 49 expressly require that the power levels of the preamble transmission are distinctly different. These amended independent claims also require that the mobile transmission involves a spreading of an access preamble. As noted, Ozluturk uses a continuous ramp-up instead of discrete power levels. Also, the short code and the access code used by Ozluturk do not spread or carry any type of preamble (or any other form of data). Hence, Ozluturk also does not spread an ‘access preamble’ as required by claims 47 and 49.
(D.I. 227/290 at JA291) (emphasis added) While the court does not find this language to be a clear disavowal of subject matter, the fact that spreading was added “to more clearly point out” a distinction over the prior art indicates that, even prior to amendment, the patentee contemplated a preamble to be spread prior to transmission. The parties have not submitted that any portion of the additional prosecution history from the '427 patent prosecution or the reexamination of the '267 patent is relevant to whether a preamble or access preamble is spread before transmission.
The parties dispute whether a preamble must be without message data.
The prosecution history of the original '267 patent did not distinguish any prior art reference on the basis that the claimed invention calls for “preamble only” transmissions. Thus, this portion of the prosecution history falls short of a clear disavowal of claim scope. However, the additional prosecution history that was not considered in the Texas litigation clearly establishes that, in order to traverse the IS-95 Standard, GBT disavowed message data being included in, or sent in conjunction with, the preamble.
The patentee asserted during reexamination that, “while IS-95 Standard does disclose ... that each successive access probe is sent at a higher power level than the previous access probe, the access probe is a preamble plus a message. It is not just a preamble alone.” (D.I. 228/291 at JA781-82) With respect to claims 27 and 28 of the '267 patent, the patentee argued: “As for the IS-95 Standard ..., the preamble of the present invention does not contain a message. The IS-95 Standard teaches sending the preamble and a message together and sending the acknowledgment to stop data transmission after receipt of a preamble and message.” (Id at JA784) The patentee incorporated this argument for independent claim 29, as well as several other claims. (Id at JA781-82)
In its brief to the Board of Patent Appeals and Interferences, GBT again consistently asserted that, whereas each access probe in the IS-95 Standard is a preamble plus a message, the claimed preambles “do not include message data.” (D.I. 228/291 at JA1160, JA1184, JA1194, JA1196) Therefore, GBT unequivocally took the position that the IS-95 Standard taught a preamble with message data and that its invention teaches a preamble without message data. In other words, GBT disclaimed subject matter during reexamination by arguing for a more narrow definition of “preamble” in order to traverse the IS-95 Standard prior art,
4. “Preamble”/“access preamble” does not necessarily comprise one or more codes that distinguish one access preamble from another
Finally, the court finds no support for GBT’s assertion that a preamble is a signal that must “compris[e] one or more codes that distinguish one access preamble from another.” GBT argues that, during prosecution of the original '267 patent, it made an explicit disclaimer that a preamble must comprise one or more codes that distinguish one preamble from another. (D.I. 208/284 at 14-17) Specifically, GBT points to the same statement discussed supra, made in response to the examiner’s rejection of proposed claims during the prosecution of the original '267 patent: “Another disclosed distinction is that the access preamble here is itself a form of code data (e.g. a signature) that is spread in essentially the same manner as other data.” (D.I. 227/290 at JA289) (emphasis added) Rather than emphasizing the portion of the statement asserting that a preamble is spread, GBT emphasizes that a preamble “is itself a form of code data (e.g. a signature).... ” However, given the context of the statement, the patentee’s intent was to make a distinction from Ozluturk on the nature of the spreading, not to limit a preamble to require distinguishing code. GBT does not point to anything in the new prosecution history that would constitute a disclaimer requiring a preamble to have distinguishing code.
Given that many mobile stations are sharing a channel to access a base station, GBT does not take an unreasonable view that it would be advantageous for the base station to be able to distinguish which preamble originated from which mobile station. However, the specification does not limit a preamble in such a way. The only time the specification arguably mentions distinguishable codes is when it teaches that the “preferred approach” is that codes “can be chosen so that identical codes are not used in the same locations for two different preambles.” ('267 patent, col. 8:37-39) (emphasis added) The same discussion, however, teaches more generally that “[t]here are many ways of generating preamble waveforms,” and even recognizes the alternative (albeit less preferable) way, of using “a single repeating code in generating each preamble.” (Id., col. 8:19-20, 8:32-33)
5. Conclusion regarding “preamble”/“access preamble”
For the • foregoing reasons, the court does not apply collateral estoppel to the claim limitations “preamble” or ■ “access preamble.” The limitations “preamble” and “access preamble” are both construed as “a signal for communicating with the base station that is spread before transmission and that is without message data.”
Defendants assert that “discrete power level” should be construed to mean “a constant distinct power level.” (D.I. 193/279) GBT submits the limitation should be accorded its plain and ordinary meaning, but does not dispute defendants’ proposed construction insofar as “discrete” is synonymous with “distinct.” (See D.I. 212/288 at 11) (“The plain and ordinary meaning of ‘discrete’ is ‘separate, distinct or non-continuous.’ ”) Therefore, the court focuses on whether a “power level” must also be “constant,” as defendants propose.
Defendants emphasize that the claims recite sending one preamble “at” a certain discrete power “level” and a next preamble “at” another higher discrete power “level.” (D.I. 210/286 at 22) They contend that the plain meaning of this language is that the first preamble is sent “at” a power level which is constant and the next preamble is sent “at” a different power level that is constant. (Id) While the court is not persuaded that the plain meaning so limits “discrete power level,” the court agrees with defendants that the intrinsic evidence requires a “power level” to be “constant.”
The specification discloses only one embodiment for ramping up successive preambles. Figure 6 shows each successive preamble at a different power level, E0 , P1( and P2:
FIG. 6 illustratively shows the common-packet channel access burst format, for each access-burst signal.... [A] first segment has a first preamble and pilot, at a first power level P0. A second segment has a second preamble and a second pilot, at a second power level P}. The third segment has a third preamble and a third pilot at a third power level
('267 patent, fig. 6, col. 5:59-6:10) The specification further teaches that “power is increased in time from preamble to preamble in a step-wise manner. The transmitted power during each preamble is constant.” (Id, col. 7:49-51) (emphasis added) This language unambiguously describes separate preambles, where each preamble .is at a power level that is “constant,” and the step-wise characteristic is seen from one preamble to another, not within a single preamble. Although claims may not always be limited to a disclosed embodiment, the patents-in-suit do not describe any other method of ramping up the power level besides that detailed in the written description and shown in the figures.
Indeed, if there is any doubt, the prosecution history also shows that a “discrete power level” must be at a “constant” level. GBT’s original '267 ■ patent application, filed.March 22,. 1999, had a specification that taught the above-mentioned embodiment in which a first, second, and third preamble have a first power level P0, sec
Following rejection of certain claims for obviousness, the patentee filed an amendment on May 6, 2002 adding proposed claims 43-49 (which issued as claims 23-26 and, after amendment, claims 27-29), each reciting transmitting “a first preamble ... at a first power level” and a second preamble “at a second power level ... higher than the first power level” (claims 43, 47-49) or “transmitting a preamble at a set power level” and “increasing power level to a new set power level, and repeating the transmitting step” (claims 44-46). (Id. at JA218-20) (emphasis added) The examiner rejected claims 43-48 as obvious or anticipated in view of U.S. Patent No. 5,841,768 to Ozluturk et al. (“Ozluturk”).
Ozluturk teaches a spread spectrum communication system for controlling initial power ramp-up. As interpreted by the examiner, it “transmits an initial minimum power level that is guaranteed to be lower than the required power level by the base station, and continues transmitting an increased power level until base station sends an indication (claimed acknowledgment).” (See id. at JA236) In response to the examiner’s rejection, GBT asserted that independent claims 43 and 44 were patentable over Ozluturk because they
specify transmission of each preamble at one “level.” Stated another way, the entire first preamble transmission is at a one “first power level,” and the entire second preamble transmission is at a one “second power level.” Claim 44 specifies transmitting a preamble at a set power level and repeating the transmitting step at a new set level. The second (or new set) power level is higher than the first power level (or increased). A continuous ramp-up extending through a preamble transmission, as in Ozluturk, would result in a preamble transmission that continues to increase (e.g. in an inclined linear manner) during the respective preamble transmission, not a complete transmission of a preamble at either “level,” as claimed. ... The express claim language therefore excludes continuous power ramp up through one or more preamble transmissions, e.g. as a continuously increasing signal during each ongoing spreading code transmission, as is apparently the case in the Ozluturk system.
(Id. at JA290) (citations omitted) (emphasis added) The patentee also stated, “Ozluturk teaches continuously repeating transmissions and a linear continuous power ramp-up. Continuous transmission and ramp-up does not provide preambles, each of which is completely at one of the different levels, or separations between preamble transmission.” (Id. at JA289) (emphasis added) Therefore, the patentee narrowed the claim limitation to a power level that is at a single or set level, or “constant.”
[T]here is no principle of patent law that the scope of a surrender of subject matter during prosecution is limited to what is absolutely necessary to avoid a prior art reference that was the basis for an examiner’s rejection. To the contrary, it frequently happens that patentees surrender more through amendment than may have been absolutely necessary to avoid particular prior art. In such cases, we have held the patentees to the scope of what they ultimately claim, and we have not allowed them to assert that claims should be interpreted as if they had surrendered only what they had to.
Norian Corp. v. Stryker Corp.,
Therefore, the intrinsic evidence requires each “discrete power level” to be distinct and constant. The specification uses the word “constant” and teaches an embodiment consistent with the court’s construction. Furthermore, the arguments that GBT made during prosecution to traverse Ozluturk extracted the word “level,” as used in “power level,” to indicate that each preamble is transmitted at a power “level” that is entirely constant. Accordingly, the court construes “discrete power level,” consistent with defendants’ proposed construction, to mean “a constant distinct power level.”
V. CONCLUSION
For the foregoing reasons, the court interprets the claim language in the '267 and '427 patents, for both Civ. Nos. 10-428 and 11-165, in the manner set forth above. An appropriate order shall issue.
ORDER
At Wilmington this 9th day of April, 2013, consistent' with the memorandum opinion issued this same date;
IT IS ORDERED that:
1. “Preamble”/“access preamble” means “a signal for communicating with the base station that is spread before transmission and that is without message data.”
2. “Discrete power level” means “a constant distinct power level.”
Notes
. U.S. Patent No. 6,574,267 Cl.
. Civ. No. 10-428.
. Civ. No. 11-165.
. The papers relevant to claim construction have been docketed in both cases. The court will reference both dockets in each citation— the first D.I. number will reference docket items in Civ. No. 10-428, and the second D.I. number will reference docket items in Civ. No. 11-165.
. For ease of reference, the court refers to those defendants from Civ. Nos. 10-428 and 11-165 that are participating in claim construction proceedings simply as “defendants.''
. For convenience, the court will cite to the '267 specification.
. GBT asserted claims 13 and 23 of the original '267 patent against Lucent and claims 23-29 against Nokia. Golden Bridge Tech., Inc. v. Nokia, Inc., Civ. No. 2:05cv151,
. For ease of reference, the court hereinafter may use "preamble” to refer to both "preamble” and “access preamble.”
. The parties agree that "spreading” a preamble means increasing the bandwidth of the preamble. (D.I. 193/279)
. See claims 45-46, 49-50, 53-54, and 58 of the '267 patent, and claims 9-10 and 26-28 of the '427 patent.
. See claims 47-48 and 55-57 of the '267 patent, and claims 29-31 of the '427 patent.
. See claims 14, 17-19 and 21-25 of the '427 patent.
. See claims 1-8 of the '427 patent.
. See claims 27-29, 42-44, 51-52, 59-60 of the '267 patent, and claims 11-13, 16, 20, 32-35, 37-38 of the '427 patent.
. See claims 27-29 of the '267 patent, and claims 11, 13, 33, 37, and 38 of the '427 patent.
. During reexamination, GBT submitted the construction from the Texas litigation. (D.I.
. Defendants "do not dispute that the preamble ... would not be understood to contain the type of message data the patents contemplate.” (D.I. 210/286 at 19-20) Apple's expert, Dr. Kakaes, testified that "the preamble does not include a message.” (D.I. 229/292 at JA1885, 219:8-220:3) Nevertheless, defendants opine that "nothing in the meaning of the term preamble’ excludes or prohibits 'message data’ (or anything else) from being transmitted before or after the preamble....” (D.I. 210/286 at 19-20) (emphasis added)
. GBT did not propose this limitation in the Texas litigation. As there is no new prosecution history regarding distinguishable codes in preambles and the specification provides no support for GBT’s proposed limitation, the court is not inclined to depart from the Texas court's construction in this regard.
. It is noteworthy that GBT also initially agreed in the instant Civ. No. 10-428 case, as well as in the Texas litigation, that a "discrete power level” is "a constant distinct power level.” (D.I. 210/286 at 25-26; D.I. 228/291 at JA820-31; D.I. 229/292 at JA2042, JA1888, JA1897, 1955) The Texas court did not construe "discrete power level." (See D.I. 228/291 at JA1237-54)
. Claims 13, 31, and 36-37 of the '427 patent recite “a plurality of constant power levels.” However, these "constant power levels” are in the context of "an access-burst ... signal comprising a plurality of segments with a plurality of constant power levels, each segment comprising [an] ... access preamble. ...” This claim language does not create any issue under the doctrine of claim differentiation, as it applies to segments of access-burst signals. Rather, the use of "constant” in those claims is consistent with the court's construction because even the "power level” of each "segment,” which comprises an access preamble, must be "constant.”
. The specification and patentee's statements also support the parties’ agreement that each power level must be "distinct.” The specification provides that the preambles are transmitted in a "step-wise manner” ('267 patent, col. 7:49-51), and the prosecution history confirms that each preamble is transmit
. "Discrete power level” could alternatively be construed synonymously using GBT's words from the prosecution history file, such as "a distinct power level that is completely at one power throughout.” However, the construction of a "distinct power level that is constant” uses the word "constant” from the specification and will be more straightforward for jurors to understand and apply.