Download HW 9 - Patent Liability Analysis

ECE 477
Digital Systems Senior Design Project
Spring 2007
Homework 9: Patent Liability Analysis
Due: Friday, February 2, at NOON
Team Code Name: Sounds Good_________________________________ Group No. __7___
Team Member Completing This Homework: _Benjamin Fogle________________________
e-mail Address of Team Member: _bnfogle______ @ purdue.edu
NOTE: This is the second in a series of four “professional component” homework assignments,
each of which is to be completed by one team member. The completed homework will count
for 20% of the individual component of the team member’s grade. The body of the report
should be 3-5 pages, not including this cover sheet, references, attachments or appendices.
Evaluation:
Component/Criterion
Score
Multiplier
Introduction and Summary
0 1 2 3 4 5 6 7 8 9 10
X1
Results of Patent/Product Search
0 1 2 3 4 5 6 7 8 9 10
X4
Analysis of Patent Liability
0 1 2 3 4 5 6 7 8 9 10
X2
Action Recommended
0 1 2 3 4 5 6 7 8 9 10
X1
List of References
0 1 2 3 4 5 6 7 8 9 10
X1
Technical Writing Style
0 1 2 3 4 5 6 7 8 9 10
X1
TOTAL
Comments:
Points
ECE 477
Digital Systems Senior Design Project
Spring 2007
1.0 Introduction
Our project, the DS3, is a self-contained speaker system containing its own amplifiers and
able to focus the sound in user-selected directions. It accomplishes the steering of the sound by
using an array of speakers all producing the same signal, but with slightly differing phases.
Another method used in addition to altering the phases is amplitude shading, where the relative
amplitudes of the speaker elements are adjusted to make the sound even more directional. The
aspect of the design most susceptible to patent liability issues is this phased speaker array.
2.0 Results of Patent and Product Search
The Yamaha Digital Sound Projector line (YSP-1, YSP-1000, YSP-1100, and YSP-800) [1]
perform a similar function to our project [3]. Like our project, these speakers are self-contained
units (minus the subwoofer) that use the phased speaker array technique to create zones of
localized sound. In the Yamaha speakers, these “beams” reflect off surfaces of the room in
which the speaker is placed in order to create full surround sound from a single speaker system.
They also have the capability to produce simple stereo effects and localized regions of sound.
Another product with similar functionality is the Pioneer PDSP-1, which uses a large
number of speakers to produce a surround sound system in almost exactly the same way as the
Yamaha line [2]. These two products are very similar to one another in many respects and both
products have capability to be controlled by a remote control, as ours will.
Both of these products use Digital Sound Project technology licensed from 1 Ltd, who holds
U.S. Patent No. 7,130,430 on a “phased array sound system,” filed on December 18, 2001 and
granted on October 31, 2006 [3]. The patent describes the technique to use several speakers with
digitally controlled delays in the inputs to each speaker to create localized regions of sound. The
text of the abstract follows:
An array of speakers are fed from a single source of audio frequency sound but each
speaker transmits the sound delayed by an amount which is determined by the distance
between a particular speaker and a selected region in space, so that sound from each
speaker constructively adds at the selected region in space. A sufficiently large number of
speakers are employed so that when sound reaches a region in space at the same moment
in time the audio volume will be increased substantially over sound in regions where
there is not constructive interference. This simple technique allows audio frequency
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ECE 477
Digital Systems Senior Design Project
Spring 2007
sound to be heard in only selected regions within the room or other auditory space.
Multiple regions with multiple soundtracks can be created by simultaneously playing
variously delayed soundtracks over each of the speakers in the array.
3.0 Analysis of Patent Liability
Using phased arrays to produce localized regions of intensity is not new, having been used in
antennae arrays for quite some time and used by ultrasounds to create an image of a fetus in the
womb, among other things. The concept is not new, but there does not seem to be any prior
mention of its use—at least terms of patents and commercial products—in the audio range for
home entertainment applications. In light of this, if our project used only delay steering to
produce the localized regions of sound, it would almost certainly be ruled substantially similar
under the doctrine of equivalents and would be in violation of 1 Ltd.’s patent on the phased
speaker array.
One caveat that might make our project sufficiently different to avoid liability is the use of
amplitude shading in conjunction with phased array. The Yamaha line and the Pioneer line both
use about twenty to thirty speakers to produce the delay steering effects, and neither system gives
any indication that it uses amplitude shading in any way (though it is possible). Our design uses
many less speakers and suffers from much less directional control of the sound as a result, so it
uses amplitude shading to help make up the difference. Since it appears that digitally controlled
amplitude shading to create localized regions of audio frequency sound is not covered by patent,
there is a good chance that our product may produce localized sound in a manner sufficiently
different from a scheme exclusively using delay steering to avoid liability. The only question is
whether or not the use of the digitally controlled delay steering in and of itself still constitutes a
violation even when insufficient to perform the steering alone.
4.0 Action Recommended
It is very possible that our project will need both amplitude shading and delay steering to
direct the sound output, so removing delay steering is not an option. Although our product could
be deemed sufficiently different from the technology patented by 1 Ltd. based on the use of
digitally controlled amplitude shading used in conjunction with delay steering, the matter would
likely be taken to court anyhow. In this case, it would have to be carefully considered whether or
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ECE 477
Digital Systems Senior Design Project
Spring 2007
not it might prove cheaper to license the phased array technology from 1 Ltd. or to come to some
other sort of arrangement than to enter litigation costly and time-consuming litigation. The cost
of litigation aside, the delay in product launch alone should the case go to court could be
extremely expensive outcome. Because of these concerns, it would be most prudent to open a
dialog with 1 Ltd. to prevent any legal action from taking place.
5.0 Summary
The DS3 performs substantially the same function as the Yamaha YSP line of Digital
Sound Projectors and the Pioneer PDSP-1, both of which use digitally controlled delay steering
technology patented by 1 Ltd. to produce localized regions of sound that can be directed
according to user input. Our product uses this same technology—which is almost certainly
infringing on the patent—in conjunction with digitally controlled amplitude shading techniques.
The combination of the two techniques, either of which alone would not have as much effect,
might be ruled substantially different from their use separately. We might be able to avoid
litigation in this way, or at least have an argument to defend in court. In any case, the matter
would have to be proven in court, whose expense and time could make licensing the technology
from 1 Ltd. an attractive alternative, even if it could be proven unnecessary.
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ECE 477
Digital Systems Senior Design Project
Spring 2007
List of References
[1] Milsap, J. P., “Phased array sound system,” U.S. Patent no. 7130430, Oct. 2006.
[2] Pioneer Europe. “PDSP-1 Loudspeakers – Pioneer Product Archive.” Pioneer.
http://www.pioneer.co.uk/uk/products/archive/PDSP-1/index.html
[3] Yamaha. “YAMAHA :: YSP-1.” Yamaha. 2006.
http://www.yamaha.com/yec/ysp1/idx_products.htm
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