Source: s3://data.kl3m.ai/documents/govinfo/USCOURTS/USCOURTS-cand-5_06-cv-05118/USCOURTS-cand-5_06-cv-05118-8/pdf.json

Nature of Suit Code: 830
Nature of Suit: Patent
Cause of Action: 35:271 Patent Infringement

---

1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

16

17

18

19

20

21

22

23

24

25

26

27

28

 This disposition is not designated for publication and may not be cited. 1

Case No. C-06-05118 JF (RS)

ORDER CONSTRUING CLAIMS OF UNITED STATES PATENTS

(JFLC3)

**E-filed 01/18/08**

NOT FOR CITATION

IN THE UNITED STATES DISTRICT COURT

FOR THE NORTHERN DISTRICT OF CALIFORNIA

SAN JOSE DIVISION

TOWNSHEND INTELLECTUAL PROPERTY,

L.L.C.,

 Plaintiff,

 v.

BROADCOM CORPORATION, 

 Defendant.

Case Number C-06-05118 JF (RS)

ORDER CONSTRUING CLAIMS OF 1

UNITED STATES PATENTS NO.

5,801,695, NO. 5,809,075, NO.

5,835,538, NO. 5,859,872, NO.

5,970,103, NO. 6,233,275, NO.

6,233,284, AND NO. 6,400,770 

[re: docket no. 71]

On November 26, 2007, the Court held a hearing for the purpose of construing disputed

terms in the claims of United States Patents No. 5,801,695 (“the ’695 patent”), No. 5,809,075

(“the ’075 patent”), No. 5,835,538 (“the ’538 patent”), No. 5,859,872 (“the ’872 patent”), No.

5,970,103 (“the ’103 patent”), No. 6,233,275 (“the ’275 patent”), No. 6,233,284 (“the ’284

patent”), and No. 6,400,770 (“the ’770 patent”). After consideration of the arguments and

evidence presented by the parties and the relevant portions of the record, the Court construes the

disputed terms as set forth below. 

Case 5:06-cv-05118-JF Document 93 Filed 01/18/08 Page 1 of 14
1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

16

17

18

19

20

21

22

23

24

25

26

27

28

 Subsequently, Analog Devices, Inc. was dismissed by stipulation of the parties. 2

 Townshend argues that this assertion lacks support. 3

2

Case No. C-06-05118 JF (RS)

ORDER CONSTRUING CLAIMS OF UNITED STATES PATENTS 

(JFLC3)

I. BACKGROUND

This case involves dial-up modem technology. Townshend Intellectual Property, LLC

(“Townshend”) alleges that certain modems sold by Broadcom Corporation (“Broadcom”)

infringe seven Townshend patents including the ’872 patent, the ’695 patent, the ’075 patent, the

’103 patent, the ’770 patent, the ’275 patent, and the ’284 patent (collectively referred to as “the

patents”). 

The patents share the same specification, with the exception of three patents (’872, ’275,

and ’284) that are continuations-in-part of the original application and thus contain some

additional material. The invention generally relates to high-speed modem technology. A modem

is used to translate digital signals from computers into analog signals, and vice versa, for

transmission over and receipt from telephone lines. The patents describe a method of utilizing

unique properties of Internet Service Provider (“ISP”) computer connections to increase the

speed of this data transmission process. In particular, the invention takes advantage of the fact

that, because ISPs often are connected to the Internet via digital telephone lines, the modem at

the ISP can transmit information more quickly. The patents describe a modem for use at the ISP

site and one for use at the end-user site that together take advantage of the faster digital telephone

lines to increase the speed of information transmission from ISP to end-user. 

In earlier litigation, Townshend asserted the patents against Analog Devices, Inc. , Agere 2

Systems, Inc., Cisco Systems, Inc., ESS Technologies, and Intel Corporation. In re Townshend

Litigation (referred to herein as the “prior case”), Case No. C-02-4833 JF (PVT). Broadcom

asserts that the majority of the defendants in the prior case sold server-side (downstream)

modems. Broadcom alleges that it is a client-side modem manufacturer and thus does not 3

infringe the patents. 

II. LEGAL STANDARD

Claim construction is a question of law to be decided by the Court. Markman v.

Case 5:06-cv-05118-JF Document 93 Filed 01/18/08 Page 2 of 14
1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

16

17

18

19

20

21

22

23

24

25

26

27

28

 415 F.3d at 1303. 4

3

Case No. C-06-05118 JF (RS)

ORDER CONSTRUING CLAIMS OF UNITED STATES PATENTS 

(JFLC3)

Westview Instruments, Inc., 52 F.3d 967, 979 (Fed. Cir. 1995), aff’d 517 U.S. 370 (1996). The

patentee’s use of a claim term in the specification is highly relevant to understanding the proper

context in which the term is used. Phillips v. AWH Corp., 415 F.3d 1303, 1315 (Fed. Cir. 2005). 

The specification is the “single best guide to the meaning of a disputed term.” Id., citing

Vitronics Corp. v. Conceptronic, Inc., 90 F.3d 1576, 1582 (Fed. Cir. 1996). 

III. DISCUSSION

A. The Court’s Previous Claim Construction

This Court construed the following disputed terms in the prior case: (1) “encoder” and

“encoding”; (2) “digital source” and “data source”; (3) “high speed,” “communication,” and

“transferring data”; (4) “codeword(s)”; and (5) “inverse filter”. Townshend contends that the

Court’s prior construction of these claim terms should be adopted because the Court properly

considered the intrinsic evidence, including the specifications and the file histories of the patents.

Broadcom argues that the Court must construe these terms again in light of new arguments raised

by Broadcom that were not previously before the Court. Broadcom also argues that the

construction should be re-evaluated in light of Phillips , which was decided after this Court’s 4

claim construction ruling in the prior case. 

Because Broadcom was not a party to the previous case, the Court will not subject it to

collateral estoppel based upon the previous claim construction. See, e.g. Tex. Instruments, Inc. v.

Linear Techs. Corp., 182 F. Supp. 2d 580, 589-90 (E.D. Tex. 2002); Nilssen v. Motorola, Inc.,

80 F. Supp. 2d 921, 924, n.4 (N.D. Ill. 2000). Instead, the Court will adopt or modify the

previous construction as is appropriate in light of the parties’ arguments in the instant case and

the current state of the law.

B. Disputed Terms

1. Encoder; Encoding

These terms appear in the ’075, ’872, ’770, ’284, and ’275 patents. A representative

claim of the ’075 patent is set forth below with the disputed term highlighted in bold. 

Case 5:06-cv-05118-JF Document 93 Filed 01/18/08 Page 3 of 14
1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

16

17

18

19

20

21

22

23

24

25

26

27

28

4

Case No. C-06-05118 JF (RS)

ORDER CONSTRUING CLAIMS OF UNITED STATES PATENTS 

(JFLC3)

1. A high speed data transfer system for communicating between a digital data

source and an analog subscriber connected to a digital telephone network by an

analog loop comprising:

an encoder coupled to said digital data source, said encoder converting an

input from said data source into a series of codewords from a set of

codewords corresponding to quantizer values utilized by said digital

telephone network;

an interface for transmitting said series of codewords in digital form from

said encoder to said digital telephone network; and

a decoder coupled by said analog loop to said digital telephone network,

wherein said analog loop provides an analog signal to said decoder, which

analog signal is an analog representation of said series of codewords, and

wherein said decoder is responsive to said analog signal to reconstruct said

series of codewords in digital form from said analog signal.

 The parties propose the following construction:

Term Townshend’s proposed

construction

Broadcom’s proposed

construction

“Encoder” A device for or method of

converting data by the use of

a code or a coded character

set in such a manner that

reconversion to the original

form is generally possible.

A server (modem) connected

digitally to the digital

telephone network for

converting the Bitstream into

a sequence of 8-bit words.

“Encoding” The method of converting the

Bitstream into a sequence of

8 bit words by a server

(modem) connected digitally

to the digital telephone

network. 

Townshend’s proposed construction adopts the Court’s construction in the prior case.

Townshend contends the Court properly considered the intrinsic evidence in arriving at this

construction. Townshend asserts that Figure 3 of the ’872 patent shows that the function of the

encoder is to “convert the data stream into a format compatible with the telephone system” (i.e.,

into “codewords”). Townshend points to the specification, which states that “[t]he

transformation performed by encoder 150 is then inverted and decoder 156 outputs data stream

126, which is a delayed estimate of the original data stream 100.” ’872 patent, col.10 lns.7-10. 

Townshend asserts that the encoder converts the data in such a manner that reconversion to the

original form is usually possible. For further support, Townshend also references the American

National Dictionary for Information Processing Systems, which defines “encode” as follows:

Case 5:06-cv-05118-JF Document 93 Filed 01/18/08 Page 4 of 14
1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

16

17

18

19

20

21

22

23

24

25

26

27

28

5

Case No. C-06-05118 JF (RS)

ORDER CONSTRUING CLAIMS OF UNITED STATES PATENTS 

(JFLC3)

to convert data by the use of a code or a coded character set in such a manner that

reconversion to the original form is possible. Encode is sometimes loosely used

when complete reconversion is not possible.

Broadcom contends that the prior claim construction is ambiguous. It argues that the

specification of the ’872 patent clearly sets out three characteristics of an “encoder”: (1) the

device is a server; (2) it is digitally connected to the digital telephone network (“DTN”); and (3)

it converts digital data into an eight bit format compatible with the telephone network. 

Townshend disputes that the device must be limited to “a server” or that the codewords must be

limited to “8-bit words.” For example, Townshend points to Figure 19 of the ’872 patent which

shows the encoder associated with a fax machine. Townshend does not dispute Broadcom’s

argument that the encoder always is connected to the Digital Telephone Network (DTN). At oral

argument, Broadcom stated that it would be willing to modify its proposed construction of these

terms, and that its main concern is the direction in which the encoder sends the data.

The intrinsic evidence supports Broadcom’s construction that the encoder sends data in

the downstream direction. See Figure 3; ’872 patent, col.10 lns.48-49 (“The channel from server

to client begins with arbitrary digital data provided as data stream 100. Encoder 150 converts

this bitstream into a sequence of eight-bit words . . . .”). When information is being sent in the

reverse, upstream, direction that task is performed by a modulator. See Figure 17; the ’872

patent, col.22 lns.11-16. Specifying that the encoder is digitally connected to the digital

telephone network ensures that the construction of the term shows the data being sent in the

downstream direction.

Accordingly, the Court adopts Broadcom’s modified construction offered at oral

argument: “Encoder” means “a device digitally connected to the digital telephone network for

converting the bitstream into a sequence of codewords;” “encoding” means “the method of

converting the bitstream into a sequence of codewords by a device connected digitally to the

digital telephone network.” 

2. “Data Source”; “Digital Source”

These terms appear in the ’695, ’075, and ’103 patents and are used interchangeably. A

representative claim of the ’075 patent is set forth below with the disputed term highlighted in

Case 5:06-cv-05118-JF Document 93 Filed 01/18/08 Page 5 of 14
1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

16

17

18

19

20

21

22

23

24

25

26

27

28

6

Case No. C-06-05118 JF (RS)

ORDER CONSTRUING CLAIMS OF UNITED STATES PATENTS 

(JFLC3)

bold. 

1. A high speed data transfer system for communicating between a digital data

source and an analog subscriber connected to a digital telephone network by an

analog loop comprising:

an encoder coupled to said digital data source, said encoder converting an

input from said data source into a series of codewords from a set of

codewords corresponding to quantizer values utilized by said digital

telephone network;

an interface for transmitting said series of codewords in digital form from

said encoder to said digital telephone network; and

a decoder coupled by said analog loop to said digital telephone network,

wherein said analog loop provides an analog signal to said decoder, which

analog signal is an analog representation of said series of codewords, and

wherein said decoder is responsive to said analog signal to reconstruct said

series of codewords in digital form from said analog signal.

The parties propose the following construction:

Term Townshend’s proposed

construction

Broadcom’s proposed

construction

“Data Source” A non-intermediary device

capable of originating digital

signals for a datatransmission system

A device directly connected

to the digital telephone

network capable of

transferring signals. “Digital Source”

Townshend’s proposed construction of these terms adopts the construction in the prior

case. The Court determined that “[t]he plain language of the claim also indicates that the signal

originates at the data source and then is transmitted through several steps to the end user.” 

8/26/04 Order at 12. Figure 3 shows the flow of data in the invention, initiating at the “data

source” or “digital source” (100). The patent specification indicates that this data stream (100) is

provided from a non-intermediary, originating source: “Data applied at data stream 100 will

appear some time later at data stream 126.” ’872 patent, col.8 lns.46-47. In other words, the

data source is the device feeding data stream 100. See ’075 patent, claim 1 (“[A]n encoder

coupled to said digital data source, said encoder converting an input from said data source . . . .”). 

Broadcom asserts that Townshend’s proposed construction is unsupported by the intrinsic

evidence. Specifically, Broadcom argues that the “non-intermediary” and “originating” terms

included in Townshend’s proposed construction are ambiguous and are found in extrinsic rather

than intrinsic evidence. Broadcom contends that the specification supports its proposed

Case 5:06-cv-05118-JF Document 93 Filed 01/18/08 Page 6 of 14
1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

16

17

18

19

20

21

22

23

24

25

26

27

28

7

Case No. C-06-05118 JF (RS)

ORDER CONSTRUING CLAIMS OF UNITED STATES PATENTS 

(JFLC3)

construction— “A device directly connected to the digital telephone network capable of

transferring signals”—pointing out that the specification specifically defines the term “data

source” as “the data source, which has direct access to the digital network (for example, the

ISDN), can transfer exact data to the central office serving the consumer of the data.” ’872 patent,

col.5, lns.52-55. Broadcom argues that the patent is “rife with support” (Opp. at 11) for its

construction of the term “data source.” See ’872 patent, col.5 lns.19-21 (“High data rates are

required in one direction only, the source of which has direct digital access to the telephone

system.”); see also col.5 lns. 33-37; col.5 lns. 41-41; col.5 lns.52-53; col.23 lns.25-27; col.28

lns.5-14. According to Broadcom, the “data source” unambiguously is a device directly

connected to the digital telephone network. Broadcom also takes issue with the inclusion

“originating,” arguing that this word is never used in the patent specification or the claims. 

Rather, Broadcom argues, the sole support for “originating” comes from a dictionary definition

that was proffered by defendants in the prior case and now should be disregarded in light of

Phillips. 

Townshend replies that the “digital source” or “data source” cannot be any device that

merely outputs or transmits signals, pointing out that any intermediate component within the

digital telephone network may, generally speaking, take a digital input signal, process it in some

way, and produce a digital output signal, but such a component should not be considered a “digital

source” or “data source.” The Court agrees with Townshend that as used here, “digital source” or

“data source” is not any device but must be a non-intermediary source as shown in Figure 3. 

Accordingly, the Court determines that the intrinsic evidence supports Townshend’s proposed

construction and once again construes the term as “a non-intermediary device capable of

originating digital signals for a data-transmission system.”

3. “High Speed”, “Communication”, “Transferring data”

These terms are used in the preambles of all of the independent claims of the patents. For

example, the ’075 patent describes “[a] high speed data transfer system for communicating

between a digital data source and an analog subscriber connected to a digital telephone network

by an analog loop comprising . . . .” ’075 patent, claim 1. 

Case 5:06-cv-05118-JF Document 93 Filed 01/18/08 Page 7 of 14
1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

16

17

18

19

20

21

22

23

24

25

26

27

28

8

Case No. C-06-05118 JF (RS)

ORDER CONSTRUING CLAIMS OF UNITED STATES PATENTS 

(JFLC3)

The parties propose the following construction:

Term Townshend’s proposed

construction

Broadcom’s proposed

construction

“High Speed” A speed of data transfer from

the provider to the end-user

between approximately

33,600 and 64,000

bits/second

A speed of data transfer from

the provider to the end-user

“Communication” above 28,800 bits/second

“Transferring data”

Townshend’s proposed construction of these terms adopts the construction in the prior

case. Townshend argues that its proposed construction is correct because in the context of the

claims the term “high speed” relates to what a person of ordinary skill in the art would have

considered “high speed” at the time of patenting. For example, the patent states that “[o]ne aspect

of the present invention comprises a system for transferring data over existing telephone

connections at rates higher than known modems or conventional methods of data transmission.” 

’872 patent, col.5 lns.11-14. Additionally, the invention relates to “a new system of data transfer

which provides the capability to receive data at high rates over existing telephone lines.” ’872

patent, col.4 lns.53-55. Townshend argues that the prosecution history supports its proposed

construction. In support of the patent applications, the applicant submitted to the United States

Patent and Trademark Office (“USPTO”) a declaration by Dr. John Cioffi, who was a professor of

Electrical Engineering at Stanford University and a leading expert in communications. In this

declaration, Dr. Cioffi stated the highest known speed at the time of filing was 33.6 kbps and that

“Mr. Townshend’s invention is a pioneering invention in the field of high speed data transfer.”

Accordingly, Townshend argues that the “high speed” data rates of this new system is defined

with respect to what was previously considered the highest known communication speed: 33.6

kbps. 

Broadcom’s proposed construction provides for a speed of data transfer of 28,800

bits/second and above. Broadcom asserts that although the claim language does not define “high

speed,” the specification provides guidance. The specification describes modems at the time of

invention as incapable of exceeding approximately 30,000 bits per second. ’872 patent, col.1

Case 5:06-cv-05118-JF Document 93 Filed 01/18/08 Page 8 of 14
1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

16

17

18

19

20

21

22

23

24

25

26

27

28

9

Case No. C-06-05118 JF (RS)

ORDER CONSTRUING CLAIMS OF UNITED STATES PATENTS 

(JFLC3)

ln.66 to col.2 ln.4 (“capable of operating at speeds up to 28,800 bits per second”); col.7 lns.61-64,

col.23 lns.3-10 (“rates up to 28,000 bits/second); col.2 lns.12-13 (“speeds approaching 30,000 bits

per second”); col.5 lns.63-67 (“asymmetrical channel capacity of “20,000 to 30,000

bits/second.”). Broadcom points out that the “33,600 bits/second” threshold now asserted by

Townshend does not appear anywhere in the patents. Additionally, the declaration by Dr. Cioffi

was written two and a half years after the effective filing date for the majority of the patents. 

Broadcom asserts that the known speed of transmission changed between the time the patents

were filed and the date the declarations were prepared and submitted to the USPTO. Broadcom

argues that the only evidence of the highest known speed at the time of the actual applications is

the V.34 Standard, and that this standard supports Broadcom’s, not Townshend’s, proposed

construction. 

Broadcom also argues that claim differention supports its proposed construction because

dependent claims in three of Townshend’s patents differ materially from the independent claims

only with respect to a rate “in excess of 33 kbps.” See ’695 patent, claim 48 (“wherein said data is

extracted at a rate in excess of 33 kbps”); ’075 patent, claim 18 (“wherein said input is extracted

from said reconstructed sequence of codewords at a rate in excess of 33 kbps”); ’538 patent, claim

34 (“wherein said data stream is transmitted as said sequence of digital codewords at an

uncompressed rate in excess of 33 kbps.”). Broadcom asserts that “high speed” must be

something greater than the rate specified in these narrower dependent claims and that

Townshend’s proposed construction would render the dependent claims meaningless. Finally,

Broadcom argues that “communication” and “transferring data” do not need to be construed

because they are commonly understood terms. 

As the Court noted in its prior decision, and as Dr. Townshend explained during the prehearing tutorial, “high speed” was not used as a precise term but rather as a term distinguishing

the present invention from the prior art based on the speed of data transfer. As such, the goal of

the invention was not to transfer data above 28.8 kbps but to approach what at the time of

patenting was the theoretical maximum of 64,000 bits/second. This range constitutes “high

speed” transmission as distinguished from the prior art. 

Case 5:06-cv-05118-JF Document 93 Filed 01/18/08 Page 9 of 14
1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

16

17

18

19

20

21

22

23

24

25

26

27

28

10

Case No. C-06-05118 JF (RS)

ORDER CONSTRUING CLAIMS OF UNITED STATES PATENTS 

(JFLC3)

Claim differentiation is not “a ‘hard and fast’ rule of construction.” Bristol-Myers Squibb

Co. v. Ben Venue Laboratories, Inc., 246 F.3d 1368, 1376 (Fed Cir. 2001). Townsend asserts that

the limitation in the dependent claims regarding speed relates not to the “high speed” limitation,

but rather the rate at which the data is “extracted.” Viewed in this way, construing the term “high

speed” to mean “above 33 kbps” would not necessarily render the dependent claims meaningless. 

The Court concludes that a person of ordinary skill in the art would understand “high

speed” (as well as the speed aspect of the corresponding terms listed above) for the purposes of

the invention to mean “a speed of data transfer from the provider to the end-user between

approximately 33,600 and 64,000 bits/second.” 

4. “Codeword(s)” and “Digital Telephone Network Codeword(s)

The term “codeword(s)” appears in all of the patents-in suit. This claim element relates to

the way signals are transported over the digital telephone network, that is, using “codewords.” 

The parties propose the following construction:

Term Townshend’s proposed

construction

Broadcom’s proposed

construction

“Codeword(s)” a set of signal elements

representing the quantized

value of a sample in PCM;

there are multiple possible

representations of the same

codeword. Particular

requirements of these

codewords are specified or

described in the G.712, G.711,

and G.701 Standards.

a set of signal elements

representing the

quantized value of a

sample in PCM; there

are multiple possible

representations of the

same codeword.

“Digital Tele”phone Network

 Codeword(s)

Townshend’s proposed construction adopts the Court’s construction in the prior case. 

Broadcom’s proposed construction differs only with respect to the reference to the communication

standards. While Townshend argues that the standards should be considered because they were

used by the telephone system that existed as of the date of the patents-in-suit, Broadcom contends

that the G.712, G.711, and G.701 Standards merely were used by the Court in the prior case as

examples of support for a broad construction of “codeword.” Broadcom asserts that reference to

Case 5:06-cv-05118-JF Document 93 Filed 01/18/08 Page 10 of 14
1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

16

17

18

19

20

21

22

23

24

25

26

27

28

11

Case No. C-06-05118 JF (RS)

ORDER CONSTRUING CLAIMS OF UNITED STATES PATENTS 

(JFLC3)

other standards, such as V.34 or ISDN, should not be precluded.

In its prior Order, the Court noted that:

. . . one of ordinary skill in the art would have understood “codewords” to include

any digital representation of a signal element corresponding to the associated

quantized value. Although the specification may have referred to the eight-bit

standard for convenience, other standards are not necessarily precluded.

8/26/04 Order at 17.

The G.17, G.711, and G.701 Standards represent the telephone industry’s standards for

“codewords” at the time of patenting. The patents incorporate by reference the ITU-T

Recommendation G.712. ’872 Patent, col.11 ln.65-col.12 ln.3. G.712 requires compliance with

the G.711 Standard, and the G.711 Standard incorporates G.701. Broadcom has not demonstrated

that other standards other than the G.712, G.711 and G.701 existed at that time. Accordingly, the

intrinsic evidence supports Townshend’s proposed construction.

Accordingly, the Court construes the term “Codeword(s)” to mean “a set of signal

elements representing the quantized value of a sample in PCM; there are multiple possible

representations of the same codeword. Particular requirements of these codewords are specified

or described in the G.712, G.711, and G.701 Standards.”

5. “Inverse filter”

The term “inverse filter” appears in claim 6 of the ’103 patent:

1. A high speed decoder for recovering a digital data stream from an analog signal

transmitted to said decoder from a digital source connected to a digital telephone

network interface via an analog loop connected to said decoder, comprising:

a clock recovery circuit including a clock estimator coupled to a clock

synchronizer [sic], said clock recovery circuit being coupled to receive an

input signal from the analog loop;

an inverse filter coupled to receive a output from the clock recovery circuit;

and

a converter coupled to the inverse filter, the converter providing an estimated

code steam [sic] in response to an output of the inverse filter, wherein

said code stream comprises a sequence of codewords associated with a

codeword set utilized by the digital telephone network.

Case 5:06-cv-05118-JF Document 93 Filed 01/18/08 Page 11 of 14
1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

16

17

18

19

20

21

22

23

24

25

26

27

28

12

Case No. C-06-05118 JF (RS)

ORDER CONSTRUING CLAIMS OF UNITED STATES PATENTS 

(JFLC3)

The parties propose the following construction:

Term Townshend’s proposed

construction

Broadcom’s proposed

construction

“Inverse Filter a filter that operates on an

input signal to produce a

compensated output signal 

A filter that inverts the

transformations performed by

the line interface 140 of

Figure 3

Townshend’s proposed construction of these terms adopts the definition used by the Court

in the prior case. Townshend argues that Broadcom’s proposed construction is an incorrect

attempt to limit the claim to a particular embodiment. 

The patent states that “the purpose of inverse filter 268 is to invert the transformation

performed by line interface 140 of Figure 3", ’695 patent, col.12 lns.58–60, and “also outputs a

delay error estimate 270 giving the timing error inherent in synchronized signal 266,” Id. at col.12

lns.61–62. Broadcom’s proposed definition ignores the interface in Figure 17. Although

Broadcom asserts that the “inverse filter” only inverts the line interface transformation, the

specification demonstrates that the inverse filter also produces a delay error estimate, ’872 patent,

col.13 lns.65-67, and it also reconstructs the compensated signal. ’872 patent, col.12 lns.61-62. 

Accordingly, the Court will adopt Townshend’s proposed construction. 

6. “Using a predetermined training pattern”, “Predetermined pattern of PCM

Codewords”

Broadcom proposes that the Court construe two related terms—“Using a predetermined

training pattern” and “Predetermined pattern of PCM Codewords”—not construed in the prior

case. The phrase “using a predetermined training pattern” appears in the ’695 patent. For

example, Claim 37 of the ’695 patent, reads as follows:

37. A high speed data transfer decoding method as claimed in claim 25. . .

further comprising the step of training said decoder using a predetermined 

training pattern.

Case 5:06-cv-05118-JF Document 93 Filed 01/18/08 Page 12 of 14
1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

16

17

18

19

20

21

22

23

24

25

26

27

28

13

Case No. C-06-05118 JF (RS)

ORDER CONSTRUING CLAIMS OF UNITED STATES PATENTS 

(JFLC3)

The parties propose the following construction: 

Term Townshend’s proposed

construction

Broadcom’s proposed

construction

“Using a predetermined

training pattern”

using a training pattern that is

determined before being used

to train the decoder

Using a training pattern that is

known both to the decoder

and the encoder prior to

training

Townshend argues that the plain reading of the claim supports its proposed construction

and the Court does not need to construe the terms. Townshend also argues that the claims do not

require that the training pattern be known to both the decoder and encoder as Broadcom proposes.

Townshend contends that Broadcom incorrectly is reading a limitation from the specification into

the claims. 

Broadcom contends that both the encoder and decoder know the pattern prior to training. 

It points to language in the specification to the effect that: “[w]hen a connection is first established

between a server and a client, both encoder 150 and decoder 156 of Fig. 3 must commence in a

state known to each other.” ’872 patent, col.17 lns.29-32. Broadcom argues that if the invention

is to function as disclosed, both the encoder and decoder must know the sequence of codewords

prior to training. 

A close reading of the specification supports Broadcom’s proposed construction. In order

for the sequence to be predetermined, it has to be known previously. Accordingly, the Court

construes the term to mean “using a training pattern that is known both to the decoder and the

encoder prior to training.”

The phrase “using a predetermined training pattern” appears in the ’872 patent. For

example, Claim 1 of the ’872 patent reads as follows:

1. In a communication system that includes a encoder and a decoder . . . .

comprising the steps of:

sending a predetermined pattern of PCM codewords from the encoder

to the digital portion of the telephone network.

Case 5:06-cv-05118-JF Document 93 Filed 01/18/08 Page 13 of 14
1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

16

17

18

19

20

21

22

23

24

25

26

27

28

14

Case No. C-06-05118 JF (RS)

ORDER CONSTRUING CLAIMS OF UNITED STATES PATENTS 

(JFLC3)

The parties propose the following construction: 

Term Townshend’s proposed

construction

Broadcom’s proposed

construction

“predetermined pattern of

PCM codewords”

a pattern of PCM codewords

that is determined before the

pattern is sent form the

encoder

set of codewords that is

utilized by the digital

telephone network and is

known to both the decoder

and encoder prior to training.

Townshend again argues that Broadcom’s proposed construction is incorrect because

Broadcom is attempting to read a limitation from the specification into the claim. Broadcom

again asserts that the encoder and the decoder both must know the PCM codewords prior to

transmission and that this view is supported by the specification. For example, the patent

specification states:

The encoder 150 sends a known pattern of 8-bit PCM codewords over the

transmission channel and the decoder 156 stores samples [that] . . . it receives. The

decoder 156 then attempts to resynchronize and equalize this signal to minimize

the difference between its output and the known pattern . . . .

’872 Patent, col.26 lns.31-32 (emphasis added).

The “known pattern” is a pattern known to both sides, or “predetermined.” Accordingly, 

the Court will adopt Broadcom’s proposed construction that a “predetermined pattern of PCM

codewords” is a “set of codewords that is utilized by the digital telephone network and is known

to both the decoder and encoder prior to training.”

IT IS SO ORDERED.

DATED: January 18, 2008 _____________________________

JEREMY FOGEL

United States District Judge

Case 5:06-cv-05118-JF Document 93 Filed 01/18/08 Page 14 of 14