IN THE UNITED STATES PATENT AND TRADEMARK OFFICE
`
`
`Sung Jun Park, et al.
`In re Patent of:
`7,881,236
`Attorney Docket No.: 00035-0009IP1
`U.S. Patent No.:
`February 1, 2011
`
`Issue Date:
`Appl. Serial No.: 12/538,514
`
`Filing Date:
`August 10, 2009
`
`Title:
`Data Transmission Method and User Equipment for the
`Same
`
`DECLARATION OF JONATHAN WELLS, PH.D.
`
`
`
`
`
`1
`
`APPLE 1003
`
`

`
`
`
`
`
`
`
`
`B. 
`C. 
`D. 
`E. 
`F. 
`
`G. 
`
`Table of Contents
`
`I. 
`Introduction ...................................................................................................... 3 
`II.  Qualifications ................................................................................................... 3 
`III.  Materials Considered ....................................................................................... 6 
`IV.  Applicable Legal Standards ............................................................................. 8 
`A.  My Understanding of Anticipation ....................................................... 8 
`B.  My Understanding of Obviousness ....................................................... 9 
`C.  My Understanding of Claim Construction .......................................... 13 
`1. 
`Effective Filing Date of the ’236 Patent ................................... 13 
`V. 
`Level of Ordinary Skill in the Art ................................................................. 14 
`VI.  Random Access Overview ............................................................................. 15 
`A.  When is Random Access Used? .......................................................... 18 
`B. 
`Types of Random Access Procedures ................................................. 19 
`C. 
`The Random Access Preamble ............................................................ 20 
`VII.  Brief Overview of the ’236 Patent ................................................................. 22 
`VIII.  Claim Construction ........................................................................................ 24 
`A. 
`Claim scope of the ’236 patent ............................................................ 25 
`IX.  Prior Art ......................................................................................................... 26 
`A.  Kitazoe Overview ................................................................................ 26 
`1. 
`Kitazoe Provisional ................................................................... 30 
`AAPA Overview ................................................................................. 33 
`3GPP TS 36.321 Overview ................................................................. 34 
`The Combination of Kitazoe, AAPA, and 3GPP TS 36.321 .............. 36 
`Reasons to Combine Kitazoe, AAPA, and 3GPP TS 36.321 ............. 54 
`The Combination of Kitazoe, the AAPA of the ’236 patent, 3GPP TS
`36.321, and Kitazoe II ......................................................................... 56 
`1. 
`Kitazoe II Provisional ............................................................... 56 
`Reasons to combine Kitazoe, the AAPA of the ’236 patent, 3GPP TS
`36.321, and Kitazoe II ......................................................................... 58 
`H.  Niu Overview ...................................................................................... 59 
`I. 
`The Combination of Kitazoe, Niu, and 3GPP TS 36.321 ................... 60 
`J. 
`Reasons to Combine Kitazoe, Niu, and 3GPP TS 36.321 .................. 64 
`K. 
`The combination of Kitazoe, Niu, 3GPP TS 36.321, and Kitazoe II .. 66 
`L. 
`Reasons to combine Kitazoe, Niu, 3GPP TS 36.321, and Kitazoe II . 66 
`Conclusions .................................................................................................... 68 
`
`
`X. 
`
`
`
`
`
`
`
`2
`
`

`
`
`
`
`
`Introduction
`
`I.
`I, Dr. Jonathan Wells, declare as follows:
`
`
`
`1.
`
`I have been retained on behalf of Petitioner (Apple Inc., Microsoft
`
`Corporation, Microsoft Mobile Oy, and Microsoft Mobile Inc. (f/k/a Nokia Inc.))
`
`to provide expert opinions in connection with this inter partes review. Specifical-
`
`ly, I have been asked to provide my opinion relating to an inquiry into the patenta-
`
`bility of claims of the U.S. Patent No. 7,881,236 (the “’236 patent”).
`
`II. Qualifications
`2.
`I have over 25 years of academic and industry experience in wireless
`
`networks (e.g., 2G, 3G and 4G networks, comprising GSM, EDGE, WCDMA,
`
`HSDPA and LTE technologies), cellular infrastructure equipment (base stations,
`
`backhaul and handsets), and wireless standards, rules and regulations (e.g., 3GPP,
`
`FCC, ETSI and CEPT). Over my career, I have worked with companies to develop
`
`and deploy radio frequency (RF) hardware for telecommunication infrastructure
`
`equipment for worldwide export, to implement marketing and product develop-
`
`ment strategies for cellular wireless products, and to participate in Federal Com-
`
`munications Commission (“FCC”), European Conference of Postal and Telecom-
`
`munications Administrations (“CEPT”), European Telecommunications Standards
`
`Institute (“ETSI”) and other technical body meetings.
`
`
`
`3
`
`

`
`
`
`
`
`
`
`3.
`
`In 1987, I received my Bachelor of Science degree in Physics with
`
`Physical Electronics (with 1st Class Honours) from the University of Bath, Bath,
`
`United Kingdom. In 1991, I received the Doctor of Philosophy (Ph.D.) degree in
`
`Physics from the University of Bath. In 1998, I received a Master of Business Ad-
`
`ministration (with distinction) from Massey University, New Zealand.
`
`4.
`
`After completing my Ph.D., I began working at the University of Bath
`
`as a Postdoctoral Research Officer. I continued to work at the University of Bath
`
`until 1992. During this time, I built novel electronic devices, and developed soft-
`
`ware models to predict their performance in wireless communication systems.
`
`5.
`
` For more than 20 years I worked in private industry designing, devel-
`
`oping and implementing various wireless communication products throughout the
`
`world.
`
`6.
`
`Specifically, from 1993 to 1994, I was a Senior Design Engineer at
`
`Matra Marconi Space, where I developed space-qualified electronic components
`
`and sub-systems for two satellite systems.
`
`7.
`
`From 1994 to 1995, I was a Senior RF Design Engineer, and from
`
`1995-1998, I was RF Group Manager, at MAS Technology (now Aviat Networks),
`
`where I, among other things, led the development of three families of innovative
`
`wireless products, oversaw the company’s European regulatory approvals, and per-
`
`sonally designed a wide range of RF devices.
`
`
`
`4
`
`

`
`
`
`
`
`
`
`8.
`
`From 1998 to 1999, I was an Engineering Group Leader, and from
`
`1999-2000 I was the Director of Wideband Products, at Adaptive Broadband (now
`
`GE Digital Energy), where I oversaw the Terrestrial Infrastructure Group, and led
`
`the development of a family of digital radio products.
`
`9.
`
`From 2000 to 2004, I was the Director of Product Development at
`
`Stratex Networks (now Aviat Networks), where I was responsible for the global
`
`product development of the company’s Outdoor Unit (ODU) portfolio of high-end
`
`digital microwave radios, which were primarily directed towards cellular applica-
`
`tions.
`
`10. From 2005 to 2007, I was the Director of Product Management and
`
`Global Regulatory Affairs at GigaBeam Corporation, where I developed the over-
`
`all product strategy for a wideband communication system for future cellular ap-
`
`plications. During this time I had responsibility for establishing a global regulatory
`
`framework for this new product, which included developing FCC (Federal Com-
`
`munications Commission) and ETSI (European Telecommunications Standards In-
`
`stitute) standards to cover the specification and regulation of the system.
`
`11. Since 2007, I have been the Managing Partner of AJIS Consulting––
`
`an independent consulting firm specializing in wireless communications and
`
`emerging wireless fields. Specifically, I analyze cellular and wireless technologies,
`
`
`
`5
`
`

`
`
`
`
`
`
`
`as well as conduct technical workshops on various wireless technologies; including
`
`cellular networks, mm-wave radios, security sensors and short range radios.
`
`12.
`
`I have given guest lectures on various aspects of technology at UC
`
`Berkeley and Carnegie Mellon University. I have authored or co-authored more
`
`than 40 scientific and industry publications relating to wireless networks, cellular
`
`infrastructure equipment, and wireless standards, rules and regulations. I also pub-
`
`lished a book titled “Multi-Gigabit Microwave and Millimeter-Wave Wireless
`
`Communications” in 2010. I have presented numerous tutorials, workshops, and
`
`lectures to industry and academic audiences on these topics. I am listed as the lead
`
`inventor on multiple patents that relate to these topics as well. I was elected a Sen-
`
`ior Member of the Institute of Electrical and Electronic Engineers (IEEE) in 1999.
`
`13. My Curriculum Vitae is attached as Exhibit 1004, which contains fur-
`
`ther details on my education, experience, publications, and other qualifications to
`
`render an expert option. My work on this case is being billed at an hourly rate, with
`
`reimbursement for actual expenses. My compensation is not contingent upon the
`
`outcome of this inter partes review.
`
`III. Materials Considered
`14.
`In forming my opinions expressed in this declaration, I have consid-
`
`ered and relied upon my education, background, and experience. I reviewed U.S.
`
`
`
`6
`
`

`
`
`
`
`
`
`
`Patent No. 7,881,236 (the “’236 patent”, Exhibit 1001) and its file history (Exhibit
`
`1002).
`
`15. Additionally, I have reviewed and relied upon the following list of
`
`materials in preparation of this declaration:
`
` U.S. Patent No. 8,180,058 (Ex. 1005, “Kitazoe”)
`
` 3rd Generation Partnership Project; Technical Specification Group Radio
`
`Access Network; Evolved Universal Terrestrial Radio Access (E-UTRA) Medium
`
`Access Control (MAC) protocol specification (Release 8), 3GPP TS 36.321
`
`V8.1.0, (March 2008) (Ex. 1007, “3GPP TS 36.321”)
`
` U.S. Patent No. 6,634,020 (Ex. 1008, “Bates”)
`
` U.S. Publication No. 20090163211 (Ex. 1009, “Kitazoe II”)
`
` U.S. Publication 20080059658 (Ex. 1010 “Williams”)
`
` Van den Brand et al., Streaming consistency: a model for efficient
`
`MPSoC design, 10th Euromicro Conference on Digital System Design Architec-
`
`tures, Methods and Tools (2007) (Ex. 1011, “Van den Brand”)
`
` U.S. Patent No. 6,161,160 (Ex. 1012, “Niu”)
`
` U.S. Provisional No. 60/955,867 (Ex. 1013, “Kitazoe Provisional”)
`
` U.S. Patent No. 6,772,417 (Ex. 1014, “Ko”)
`
` U.S. Patent No. 7,675,905 (Ex. 1015, “Delaney”)
`
` U.S. Provisional No. 61/015,159 (Ex. 1016, “Kitazoe II Provisional”)
`
`
`
`7
`
`

`
`
`
`
`
`
`
` Joint Claim Construction Statement from Case Nos. 15-542-SLR-SRF,
`
`15-543-SLR-SRF, 15-544-SLR-SRF, 15-545-SLR-SRF, 15-546-SLR-SRF, 15-
`
`547-SLR-SRF filed in N.D. Del. On May 17, 2016 (Ex. 1017, “Joint Claim Con-
`
`struction Statement”)
`
`16.
`
`I have also considered all other materials cited herein.
`
`IV. Applicable Legal Standards
`A. My Understanding of Anticipation
`I understand that documents and materials that qualify as prior art can
`
`17.
`
`be used to invalidate a patent claim as anticipated or as obvious.
`
`18.
`
`I understand that, once the claims of a patent have been properly con-
`
`strued, the second step in determining anticipation of a patent claim requires a
`
`comparison of the properly construed claim language to the prior art on a limita-
`
`tion-by-limitation basis.
`
`19.
`
`I understand that a prior art reference “anticipates” an asserted claim,
`
`and thus renders the claim invalid, if all elements of the claim are disclosed in that
`
`prior art reference, either explicitly or inherently (i.e., necessarily present).
`
`20.
`
`I understand that anticipation in an inter partes review must be shown
`
`by a preponderance of the evidence.
`
`
`
`8
`
`

`
`
`
`
`
`
`
`B. My Understanding of Obviousness
`I understand that a patent claim is invalid if the claimed invention
`
`21.
`
`would have been obvious to a person of ordinary skill in the field at the time of the
`
`claimed invention. This means that even if all of the requirements of the claim
`
`cannot be found in a single prior art reference that would anticipate the claim, the
`
`claim can still be invalid.
`
`22. As part of this inquiry, I have been asked to consider the level of ordi-
`
`nary skill in the field that someone would have had at the time the claimed inven-
`
`tion was made. In deciding the level of ordinary skill, I considered the following:
`
` the levels of education and experience of persons working in the field;
`
` the types of problems encountered in the field; and
`
` the sophistication of the technology.
`
`23. To obtain a patent, a claimed invention must have, as of the priority
`
`date, been nonobvious in view of the prior art in the field. I understand that an in-
`
`vention is obvious when the differences between the subject matter sought to be
`
`patented and the prior art are such that the subject matter as a whole would have
`
`been obvious at the time of the invention to a person having ordinary skill in the
`
`art.
`
`24.
`
`I understand that a person of ordinary skill in the art provides a refer-
`
`ence point from which the prior art and claimed invention should be viewed. This
`
`
`
`9
`
`

`
`
`
`
`
`
`
`reference point prevents one from using his or her own insight or hindsight in de-
`
`ciding whether a claim is obvious.
`
`25.
`
`I also understand that an obviousness determination includes the con-
`
`sideration of various factors such as (1) the scope and content of the prior art, (2)
`
`the differences between the prior art and the asserted claims, (3) the level of ordi-
`
`nary skill in the pertinent art, and (4) the existence of secondary considerations
`
`such as commercial success, long-felt but unresolved needs, failure of others, etc.
`
`26.
`
`I understand that an obviousness evaluation can be based on a combi-
`
`nation of multiple prior art references. I understand that the prior art references
`
`themselves may provide a suggestion, motivation, or reason to combine, but other
`
`times the nexus linking two or more prior art references is simple common sense. I
`
`further understand that obviousness analysis recognizes that market demand, rather
`
`than scientific literature, often drives innovation, and that a motivation to combine
`
`references may be supplied by the direction of the marketplace.
`
`27.
`
`I understand that if a technique has been used to improve one device,
`
`and a person of ordinary skill in the art would recognize that it would improve sim-
`
`ilar devices in the same way, using the technique is obvious unless its actual appli-
`
`cation is beyond his or her skill.
`
`28.
`
`I also understand that practical and common sense considerations
`
`should guide a proper obviousness analysis, because familiar items may have ob-
`
`
`
`10
`
`

`
`
`
`
`
`
`
`vious uses beyond their primary purposes. I further understand that a person of or-
`
`dinary skill in the art looking to overcome a problem will often be able to fit to-
`
`gether the teachings of multiple publications. I understand that obviousness analy-
`
`sis therefore takes into account the inferences and creative steps that a person of
`
`ordinary skill in the art would employ under the circumstances.
`
`29.
`
`I understand that a particular combination may be proven obvious by
`
`showing, among other things, that it was obvious to try the combination. For ex-
`
`ample, when there is a design need or market pressure to solve a problem and there
`
`are a finite number of identified, predictable solutions, a person of ordinary skill
`
`has good reason to pursue the known options within his or her technical grasp be-
`
`cause the result is likely the product not of innovation but of ordinary skill and
`
`common sense.
`
`30. The combination of familiar elements according to known methods is
`
`likely to be obvious when it does no more than yield predictable results. When a
`
`work is available in one field of endeavor, design incentives and other market forc-
`
`es can prompt variations of it, either in the same field or a different one. If a per-
`
`son of ordinary skill can implement a predictable variation, the patent claim is like-
`
`ly obvious.
`
`31.
`
`It is further my understanding that a proper obviousness analysis fo-
`
`cuses on what was known or obvious to a person of ordinary skill in the art, not
`
`
`
`11
`
`

`
`
`
`
`
`
`
`just the patentee. Accordingly, I understand that any need or problem known in
`
`the field of endeavor at the time of invention and addressed by the patent can pro-
`
`vide a reason for combining the elements in the manner claimed.
`
`32.
`
`I understand that a claim can be obvious in light of a single reference,
`
`without the need to combine references, if the elements of the claim that are not
`
`found explicitly or inherently in the reference can be supplied by the common
`
`sense of one of skill in the art.
`
`33.
`
`I understand that secondary indicia of non-obviousness may include
`
`(1) a long felt but unmet need in the prior art that was satisfied by the invention of
`
`the patent; (2) commercial success of processes covered by the patent; (3) unex-
`
`pected results achieved by the invention; (4) praise of the invention by others
`
`skilled in the art; (5) taking of licenses under the patent by others; (6) deliberate
`
`copying of the invention; (7) failure of others to find a solution to the long felt
`
`need; and (8) skepticism by experts. I understand that evidence of secondary indi-
`
`cia of non-obviousness, if available, should be considered as part of the obvious-
`
`ness analysis.
`
`34.
`
`I also understand that there must be a relationship between any such
`
`secondary considerations and the invention. I further understand that contempora-
`
`neous and independent invention by others is a secondary consideration supporting
`
`an obviousness determination.
`
`
`
`12
`
`

`
`
`
`
`
`
`
`35.
`
`In sum, my understanding is that prior art teachings are properly com-
`
`bined where a person of ordinary skill in the art having the understanding and
`
`knowledge reflected in the prior art and motivated by the general problem facing
`
`the inventor, would have been led to make the combination of elements recited in
`
`the claims. Under this analysis, the prior art references themselves, or any need or
`
`problem known in the field of endeavor at the time of the invention, can provide a
`
`reason for combining the elements of multiple prior art references in the claimed
`
`manner.
`
`36.
`
`I understand that obviousness in an inter partes review must be shown
`
`by a preponderance of the evidence.
`
`C. My Understanding of Claim Construction
`I understand that, during an inter partes review, claims are to be given
`
`37.
`
`their broadest reasonable construction in light of the specification as would be read
`
`by a person of ordinary skill in the relevant art as of the effective filing date of the
`
`patent in question.
`
`1.
`Effective Filing Date of the ’236 Patent
`38. The ’236 patent issued from U.S. Application No. 12/538,514, filed
`
`August 10, 2009. The ’236 patent claims the benefit of U.S. Provisional Applica-
`
`tion No. 61/087,988, filed August 11, 2008. The ’236 patent also claims priority to
`
`a Korean patent application numbered 10-2009-0057128, which was filed on June
`
`
`
`13
`
`

`
`
`
`
`
`
`
`29, 2009. Accordingly, the earliest possible priority date for the ’236 patent is Au-
`
`gust 11, 2008 (hereinafter the “Critical Date”).1
`
`V. Level of Ordinary Skill in the Art
`
`39. A person of ordinary skill in the art (“POSA”) at the time of the ’236
`
`patent2 would have had a Master’s of Science Degree in an academic area empha-
`
`sizing Electrical Engineering, Physics, Computer Engineering, or an equivalent
`
`field (or a similar technical Master’s Degree, or higher degree) with a concentra-
`
`tion in wireless communication and networking systems. Alternatively, a POSA
`
`would have had a Bachelor’s degree (or higher) in an academic area emphasizing
`
`Electrical Engineering, Physics, Computer Engineering, or an equivalent field as
`
`well as at least 2 years of academic or industry experience in wireless communica-
`
`1 This is not an acknowledgement that the ’373 patent is entitled to its pro-
`
`claimed priority date, but rather merely an acknowledgement of the earliest pro-
`
`claimed priority date of the ’373 patent for the purposes of the present analysis.
`
`2 Unless noted otherwise, references herein to the level of ordinary skill in
`
`the art and what would have been known or understood by a POSA refers to the
`
`level of skill and knowledge of a POSA at or before the Critical Date, but would
`
`also be applicable as of the filing date of Korean patent application 10-2009-
`
`0057128.
`
`
`
`14
`
`

`
`
`
`
`
`
`
`tions and networking systems. A POSA would also have had experience with the
`
`wireless Standard Setting Organizations such as ETSI, IEEE, and 3GPP, and
`
`would have been familiar with relevant standards and draft standards directed to
`
`wireless communications. Additional education in a relevant field, such as electri-
`
`cal engineering or physics, or industry experience may compensate for a deficit in
`
`one of the other aspects of the requirements stated above. I am familiar with the
`
`knowledge and capabilities of one of ordinary skill in these areas based on my ex-
`
`perience working with industry, with undergraduate and post-graduate students,
`
`with colleagues from academia, and with engineers practicing in industry.
`
`VI. Random Access Overview
`40. A mobile wireless communication system is a wireless system that
`
`supports communications with mobile subscribers (e.g., mobile handsets). Sub-
`
`scribers of such a system, which may include both fixed and mobile subscribers,
`
`communicate via a central controller (e.g., a base station) within a communication
`
`network. When individual subscribers have traffic to transmit (for example, mak-
`
`ing a phone call or sending an email), the centralized controller coordinates the ac-
`
`tivity.
`
`41.
`
`In a cellular system, there can be many subscribers who have data to
`
`transmit, and need access to the shared communication channel (the time-
`
`bandwidth resources available to users in that area). Such transmissions are not
`
`
`
`15
`
`

`
`
`
`
`
`
`
`regular, and often multiple users wish to send data simultaneously. A given proto-
`
`col might make use of a centralized controller (such as a teacher in a classroom) to
`
`coordinate the transmissions of different users (such as students asking questions
`
`or giving answers). Such a system might be simple or complex, depending on the
`
`nature of the communication, the number of users potentially wishing to access the
`
`shared communications channel at the same time, and the amount of resources that
`
`are available for allocation by the central controller. In a cellular system, such a
`
`process is sometimes referred to as “random access.”
`
`42. One of the first random access systems was a protocol called ALO-
`
`HA, developed by the University of Hawaii around 1970.3 Here a satellite system
`
`was used to connect remote campuses on different islands with a central campus
`
`near Honolulu containing a shared, central computer. When a user at a remote
`
`campus wanted to access the central computer, a radio device at the remote campus
`
`would transmit a message to the satellite, which would relay the signal onto a radio
`
`device located at the central campus. If (and only if) the message was properly re-
`
`ceived, the central campus would transmit an acknowledgement message. The
`
`
`3 N. Abramson, "THE ALOHA SYSTEM—Another alternative for comput-
`
`er communications," Proceedings of the Fall Joint Computer Conference, pp. 281-
`
`5, Nov. 1970. (Exhibit APPL-1017).
`
`
`
`16
`
`

`
`
`
`
`
`
`
`remote station would wait a given time for this acknowledgment. If none was re-
`
`ceived, the initial access would be considered unsuccessful, and the remote termi-
`
`nal would continue to retransmit the initial message until an acknowledgment was
`
`successfully received.
`
`43. The main reason why an acknowledgement may not be received is
`
`that, in a system with many users, more than one user may be trying to access the
`
`communication channel at the same time. In such a case, the multiple messages
`
`may interfere, and a garbled message may be received at the central terminal,
`
`which could not then issue an acknowledgement signal. To stop the retransmitted
`
`messages from the multiple users from continuing to interfere with each other, the
`
`retransmission protocol needs to ensure that the retransmission times from the mul-
`
`tiple users are different. Thus, in the ALOHA system, retransmissions occurred
`
`after a random period of time.
`
`44. This is depicted in the figure below. Here user 1 communicates suc-
`
`cessfully, but transmissions from users 2 and k overlap. However the retransmis-
`
`sions from these two users, now at different times, do not interfere and thus both
`
`successfully access the communication channel.
`
`
`
`17
`
`

`
`
`
`
`
`
`
`[Source: Fn. 1.]
`
`45. Such a system works well in the case of a few users, where messages
`
`
`
`need to be sent relatively infrequently. The basic ALOHA protocol has been ex-
`
`tensively modified over the years to support more users, more efficiently, over dif-
`
`ferent communications channels. Even today’s cellular systems retain some as-
`
`pects of the early ALOHA systems.
`
`A. When is Random Access Used?
`46. Random access is used in a cellular system whenever a user device
`
`has a desire to connect to a channel in order to transmit data. Two examples of
`
`when random access is required include the following:
`
`
`
`18
`
`

`
`
`
`
`
`
`
`47.
`
`Initial access: When not in active use, a mobile device will go into a
`
`low power state to conserve battery power. This is often known as an “idle” mode.
`
`When data arrives to be transmitted (e.g., a user wants to make a call or send a
`
`message), a phone waking up from idle mode will need to perform random access
`
`to connect and resynchronize with the network. Similarly, when a mobile device is
`
`first powered on, it needs to connect to and synchronize with the network, and will
`
`perform random access to accomplish this.
`
`48. Handover: When an active user is mobile, and travels from the cover-
`
`age area of one base station to the coverage area of another, a random access pro-
`
`cedure may be required to connect and synchronize to the new base station.
`
`B.
`Types of Random Access Procedures
`49. There are many different types of random access protocols and proce-
`
`dures. However each of these can be categorized into two distinct forms:
`
`50. Contention-based random access: In a contention-based random ac-
`
`cess procedure, there is an expectation that multiple subscribers will be requesting
`
`access to the communication channel at the same time, and thus collisions may oc-
`
`cur. For example, during normal cellular operation, there may be many users in
`
`the same area (i.e., the same cell) sending the same request to access the channel at
`
`the same time, all of which may be colliding. As such, the random access proce-
`
`dure will need to properly determine which of many users sent which of many re-
`
`
`
`19
`
`

`
`
`
`
`
`
`
`quests, in order to properly allocate resources amongst the many competing users.
`
`Further, the random access procedure will need to recognize when such a collision
`
`has occurred, and resolve the contention in a predictable way.
`
`51. Non-contention based random access (or contention-free random ac-
`
`cess): In this type of procedure, the possibility of collision for a particular user ac-
`
`cessing a resource is effectively eliminated, such as by ensuring that no other user
`
`will access the resource at the same time in a way that will cause such a collision.
`
`An example of such a scenario may be during handover where a known user’s
`
`connection is being handed over from one base station to another base station. In
`
`such a controlled event, the network can inform the user of some unique identity to
`
`prevent its request from colliding with requests from other users.
`
`C. The Random Access Preamble
`52. The random access procedure in modern cellular systems is handled
`
`not by retransmission after a random delay such as in the early ALOHA systems,
`
`but with an initial transmission in a known format, known as a preamble.
`
`53.
`
`In a practical random access procedure, a user terminal may select and
`
`transmit one of a limited number of patterns or signatures called a preamble, where
`
`the preamble value differentiates requests coming from different users. If two us-
`
`ers happen to use the same preamble at same time then a collision occurs. Sup-
`
`pose, for example, that there are 16 such patterns or signatures available for the us-
`
`
`
`20
`
`

`
`
`
`
`
`
`
`er to choose for the very first message of a connection procedure. If all users are
`
`required to select one of the 16 preambles at random, there is only a 1/16 chance
`
`that a second user will pick the same preamble. Thus the chances of the two users’
`
`access requests colliding are relatively small. However if there are 16 users re-
`
`questing access at the same time, there is a much higher risk of a collision because
`
`there is a large amount of contention for the resource. Thus the selection of the
`
`number of preambles from which user terminals can choose is a trade-off between
`
`the designed capabilities of the network and implementation complexities.
`
`54.
`
`In a practical connection procedure, the user terminal selects one of
`
`the preambles randomly. This results in the possibility of collision if the same pre-
`
`amble is being used by another user terminal at the same time. Thus a contention-
`
`based random access procedure is required for allocating access and resources to
`
`the individual users. However, in the case of the user terminal already being con-
`
`nected to the network, the network can inform the user terminal about which pre-
`
`amble it should use, and thus a non-contention based procedure can be employed.
`
`For example, in a handover scenario, the user terminal may already be connected
`
`to one base station, and can receive from it an indication of a preamble to use when
`
`connecting to a new base station.
`
`55. Furthermore, the transmission of a preamble as part of the random ac-
`
`cess procedure allows a number of additional benefits. For example, the preamble
`
`
`
`21
`
`

`
`
`
`
`
`
`
`can be repetitively transmitted to form a reference signal upon which the network
`
`can perform useful channel measurements – such as, for example, estimating the
`
`quality of the channel or determining the delay between the user terminal seeking
`
`access and the connected base station. Additionally, the preambles themselves can
`
`be used to provide additional information to the network. For example, the set of
`
`possible preambles could be divided into subsets, and thus a user terminal may
`
`randomly select a preamble from within a particular subset to provide some addi-
`
`tional guidance to the network.
`
`VII. Brief Overview of the ’236 Patent
`56. The ’236 patent describes “a data transmission method and a user
`
`equipment for the same” related to a “random access procedure” between a user
`
`equipment (UE) and a base station. ’236 patent, 3:42-59, 4:42-43. The patent de-
`
`scribes that “a UE performs the random access procedure,” for example, “when the
`
`UE performs initial access” to a base station, or “when there is uplink data trans-
`
`mission in a situation where uplink time synchronization is not aligned or where a
`
`specific radio resource used for requesting radio resources is not allocated[.]” Id.
`
`at 3:42-57. FIG. 5 from the ’236 patent shows an example random access proce-
`
`dure performed between a UE and an eNB (a base station):
`
`
`
`22
`
`

`
`
`
`User
`equipment
`
`
`
`Base
`station
`
`
`
`Message 1
`
`Message 2
`
`Message 3
`
`Message 4
`
`
`
`’236 patent, Detail of FIG. 5 (annotated)
`
`57. The ’236 patent describes that a random access procedure begins with
`
`the UE “transmitting a random access preamble to the” base station (referred to as
`
`“message 1”). Id. at 4:4-7. The UE then “receiv[es] a random access response”
`
`(referred to as “message 2”) from the base station “in correspondence with the
`
`transmitted random access preamble.” Id. at 4:7-9. The UE then “transmit[s] an
`
`uplink message” (referred to as “message 3”) to the base station “using the infor-
`
`mation received by the random access response message.” Id. at 4:11-12. The UE
`
`then “receiv[es] a message” (referred to as “message 4” o