(12) United States Patent
`Dahlman et al.
`
`(10) Patent No.:
`(45) Date of Patent:
`
`US 9,532,355 B2
`*Dec. 27, 2016
`
`USO09532355B2
`
`(54)
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`(71)
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`(72)
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`(73)
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`(*)
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`(21)
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`TRANSMISSION OF SYSTEM
`INFORMATION ON ADOWNLINK SHARED
`CHANNEL
`
`Applicant: Telefonaktiebolaget LM Ericsson
`(PUBL), Stockholm (SE)
`Inventors: Erik Dahlman, Bromma (SE); Vera
`Vukajlovic Kenehan, Stockholm (SE)
`Assignee: Telefonaktiebolaget LM Ericsson
`(publ), Stockholm (SE)
`Subject to any disclaimer, the term of this
`patent is extended or adjusted under 35
`U.S.C. 154(b) by 0 days.
`This patent is Subject to a terminal dis
`claimer.
`
`Notice:
`
`Appl. No.: 14/639,287
`Filed:
`Mar. 5, 2015
`
`Prior Publication Data
`US 2015/O1816OO A1
`Jun. 25, 2015
`Related U.S. Application Data
`Continuation of application No. 12/664.347, filed as
`application No. PCT/SE2008/050407 on Apr. 10,
`2008, now Pat. No. 8,995,357.
`(Continued)
`
`Int. C.
`H047 72/04
`H04W 48/12
`U.S. C.
`CPC ......... H04W 72/0446 (2013.01); H04W 48/12
`(2013.01)
`
`(2009.01)
`(2009.01)
`
`Field of Classification Search
`CPC. H04L 1/08; H04L 2001/0093: H04W 48/12:
`HO4W 72/0446
`See application file for complete search history.
`
`(56)
`
`References Cited
`
`U.S. PATENT DOCUMENTS
`
`7.675,852 B1* 3/2010 Arundale ........... HO4B 7, 18506
`370,229
`
`7,680,507 B2
`
`3/2010 Cheng et al.
`(Continued)
`
`FOREIGN PATENT DOCUMENTS
`
`EP
`JP
`
`6, 2007
`17990O3 A1
`5, 2006
`2006136O23 A
`(Continued)
`
`OTHER PUBLICATIONS
`
`Samsung. “Draft text proposal capturing agreements on system
`information.” 3GPP TSG-RAN2 Meeting #58, Tcloc R2-072205,
`Kobe, Japan, May 7-11, 2007, pp. 1-8.*
`(Continued)
`
`Primary Examiner — Siming Liu
`(74) Attorney, Agent, or Firm — Coats & Bennett,
`P.L.L.C.
`
`ABSTRACT
`(57)
`In one embodiment, a method of transmitting system infor
`mation on a downlink shared channel structured as succes
`sive subframes includes transmitting (400-416) system
`information in regularly occurring time windows, each time
`window spanning some number of Successive subframes.
`The method further includes indicating (406/408) to receiv
`ing user equipment (120) which subframes within a given
`time window carry system information. The method and
`variations of it are applied, for example, to the transmission
`of dynamic system information on the downlink shared
`channel or other downlink channel in a 3GPP E-UTRA
`wireless communication network (100).
`
`36 Claims, 6 Drawing Sheets
`
`
`
`SESUBFRAME FIRSTSBFRA
`INTHE SYSTEMNFORATIONNINW
`
`FRANSMTSYSTEM
`INFORMATION INTH
`SUFRAME?
`
`YES
`
`LASTSUBFRAME
`INTHE WINC
`
`NO
`
`402
`N
`
`404
`YES SET CONTROL
`CHANNEL
`RNTIES-RN
`
`
`
`
`
`SETCONTROL CHAMNEL
`RNTI-S-RNT
`
`TRANSMSYSTEMINFORMATION
`ONTHEL-SCHWITHIN THE SUBFRAME
`
`414
`NEXTSUBFRAMEN
`INTHEWINDOW
`
`LASTSUBFRAME
`INTHEWINOW
`
`412
`
`416
`
`ERICSSON EXHIBIT 2008
`Apple, Inc. v. Telefonaktiebolaget LM Ericsson
`IPR2022-00338, Page 1
`
`

`

`US 9,532,355 B2
`Page 2
`
`Related U.S. Application Data
`
`FOREIGN PATENT DOCUMENTS
`
`(60) Provisional application No. 60/944,628, filed on Jun.
`18, 2007.
`
`JP
`WO
`WO
`
`20095.12391 A
`2007052917 A1
`2007073079 A1
`
`3, 2009
`5, 2007
`6, 2007
`
`(56)
`
`References Cited
`
`U.S. PATENT DOCUMENTS
`
`OTHER PUBLICATIONS
`
`Samsung. "System information scheduling and change notification.
`* 3GPP TSG-RAN2 Meeting #58, Tcloc R2-071912, Kobe, Japan,
`May 7-11, 2007, pp. 1-6.*
`Ericsson. “Transmission of dynamic system information.” TSG
`8,995,357 B2 * 3/2015 Dahlman .................. HO4L 1.08
`RAN2H58bis, R2-072543. Oriando, FL, US, Jun. 25-29, 2007, pp.
`2003. O133431 A1
`7, 2003 Rudolf
`3703
`1-4.
`Ericsson. “Transmission of dynamic system information.” 3GPP
`2004/0219917 A1* 11/2004 Love ..................... HO4L 1,1671
`2006/0034245 A1
`2/2006 Nguyen
`556 TSG-RAN2 Ad-hoc Meeting. Tdoc R5-075559, Vienna, Austria,
`Dec. 13-14, 2007, pp. 1-4.
`2007/0217362 A1
`9/2007 Kashima ............... Holyga
`3rd Generation Partnership Project. "3rd Generation Partnership
`ck
`Project; Technical Specification Group Radio Access Network;
`9/2008 Marinier ............... H04,
`2008/0225765 A1
`Evolved Universal Terrestrial Radio Access (E-UTRA) and Evolved
`9/2008 Tenny
`2008/0225823 A1
`Universal Terrestrial Radio Access Network (E-UTRAN); Overall
`2009,013 1057 A1* 5, 2009 Dimou. .................. HO4W 16/02
`description; Stage 2 (Release 8). 3GPP TS 36.300, V8.0.0. Mar.
`455,436
`2007, Sophia Antipolis Valbonne, France, pp. 1-82.
`
`ck
`
`2009, O303939 A1 12, 2009 Umesh et al.
`2010.0167750 A1
`7, 2010 Lee et al.
`
`* cited by examiner
`
`ERICSSON EXHIBIT 2008
`Apple, Inc. v. Telefonaktiebolaget LM Ericsson
`IPR2022-00338, Page 2
`
`

`

`ERICSSON EXHIBIT 2008
`Apple, Inc. v. Telefonaktiebolaget LM Ericsson
`IPR2022-00338, Page 3
`
`

`

`U.S. Patent
`
`Dec. 27, 2016
`
`Sheet 2 of 6
`
`
`
`ERICSSON EXHIBIT 2008
`Apple, Inc. v. Telefonaktiebolaget LM Ericsson
`IPR2022-00338, Page 4
`
`

`

`U.S. Patent
`
`Dec. 27, 2016
`
`Sheet 3 of 6
`
`US 9,532,355 B2
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`SET SUBFRAME = FIRST SUBFRAME
`INTHE SYSTEM.INFORMATION WINDOW
`
`400
`
`402
`
`TRANSMIT SYSTEM
`INFORMATION IN THE
`SUBFRAME?
`
`LAST SUBFRAME
`INTHE WINDOW
`
`SET CONTROL
`CHANNEL
`RNTIES-RNT
`
`SET CONTROL CHANNEL
`RNT - S-RNT
`
`TRANSMIT SYSTEM.INFORMATION
`ONTHE DL-SCH WITHIN THE SUBFRAME
`
`NEXT SUBFRAME
`INTHE WINDOW
`
`LAST SUBFRAME
`INTHE WINDOW2
`
`412
`
`416
`
`FIG. 4
`
`ERICSSON EXHIBIT 2008
`Apple, Inc. v. Telefonaktiebolaget LM Ericsson
`IPR2022-00338, Page 5
`
`

`

`U.S. Patent
`
`Dec. 27, 2016
`
`Sheet 4 of 6
`
`US 9,532,355 B2
`
`SET SUBFRAME = FIRST SUBFRAME
`INTHE SYSTEM.INFORMATION WINDOW
`
`500
`
`
`
`
`
`DEMODULATE AND DECODE
`THE L1/L2 CONTROL CHANNEL
`OF THE CURRENTSUBFRAME
`
`
`
`
`
`
`
`CONTROL CHANNEL
`RNTI-S-RNT OR
`ES-RNTI?
`
`YES
`
`DEMODULATE AND DECODE CORRESPONDING
`DL-SCHTRANSPORT BLOCK
`
`
`
`
`
`
`
`CONTROL CHANNEL
`RNTIES-RNT OR
`LAST SUBFRAME?
`
`
`
`
`
`NEXTSUBFRAME
`NTHE WINDOW
`
`FIG. 5
`
`ERICSSON EXHIBIT 2008
`Apple, Inc. v. Telefonaktiebolaget LM Ericsson
`IPR2022-00338, Page 6
`
`

`

`U.S. Patent
`
`Dec. 27, 2016
`
`Sheet S of 6
`
`US 9,532,355 B2
`
`s
`
`t
`
`ERICSSON EXHIBIT 2008
`Apple, Inc. v. Telefonaktiebolaget LM Ericsson
`IPR2022-00338, Page 7
`
`

`

`U.S. Patent
`
`Dec. 27, 2016
`
`Sheet 6 of 6
`
`US 9,532,355 B2
`
`O
`E------
`O
`
`s
`d
`C
`92-------S2-------------
`
`r
`
`Suu O
`
`s
`CO
`E------92-------------------
`
`Z '501-J
`
`
`
`CN
`D
`CO
`
`CO
`
`S
`O
`E ------92-------IS2-------------
`
`0sü o
`
`ERICSSON EXHIBIT 2008
`Apple, Inc. v. Telefonaktiebolaget LM Ericsson
`IPR2022-00338, Page 8
`
`

`

`US 9,532,355 B2
`
`1.
`TRANSMISSION OF SYSTEM
`INFORMATION ON ADOWNLINK SHARED
`CHANNEL
`
`RELATED APPLICATION
`
`The present application is a continuation of U.S. patent
`application Ser. No. 12/664.347, which was filed on Dec. 11,
`2009, which claims priority to PCT/SE2008/050407, which
`was filed on Apr. 10, 2008, which claims priority to U.S.
`Provisional Patent Application No. 60/944,628, which was
`filed on Jun. 18, 2007, all of which are incorporated by
`reference herein in their entirety.
`
`TECHNICAL FIELD
`
`10
`
`15
`
`The present invention generally relates to wireless com
`munication networks, and particularly relates to the trans
`mission of system information to user equipment (UE)
`operating in Such networks, such as the transmission of
`system information by radio base stations in a wireless
`communication network configured according to 3GPP
`E-UTRA (evolved Universal Terrestrial Radio Access) stan
`dards, also referred to as 3GPP LTE (Long Term Evolution).
`
`25
`
`BACKGROUND
`
`30
`
`40
`
`45
`
`In the 3GPP LTE, downlink user-data transmission is
`carried out on the Downlink Shared Channel (DL-SCH)
`transport channel. In LTE, the time dimension is divided into
`radio frames of length 10 ms, where each radio frame
`consists of 10 subframes, each of length 1 ms corresponding
`to 14 OFDM (orthogonal frequency-division multiplexing)
`symbols. Each subframe consists of two slots, each of length
`0.5 ms or seven OFDM symbols. Note that, in case of Time
`35
`Division Duplex (TDD), only a subset of the subframes of
`one frame is available for downlink transmission. On the
`other hand, in case of Frequency Division Duplex (FDD), all
`subframes on a downlink carrier are available for downlink
`transmission.
`In LTE, the overall time/frequency-domain physical
`resource is divided into resource blocks, where each
`resource block consists of twelve OFDM subcarriers during
`one slot. DL-SCH transmission to a UE is carried out using
`a set of Such resource blocks during one subframe. Layer
`1/Layer 2 (L1/L2) control signaling, also known as the
`Physical Downlink Control Channel (PDCCH), is transmit
`ted at the beginning of each subframe. The L1/L2 control
`channel is typically used to inform a UEabout various items.
`For example, the L1/L2 control channel may identify
`whether the DL-SCH carries data to the UE in the given
`subframe. More specifically, the L1/L2 control channel then
`includes the RNTI (Radio Network Temporary Identifier)
`associated with the UE for which the DL-SCH carries data
`in the given subframe. The L1/L2 control channel then also
`identifies the physical resource, more specifically the spe
`cific set of resource blocks that is used for the DL-SCH
`transmission to the specific UE in the given subframe.
`Moreover, the L17L2 control channel then identifies the
`transport format (e.g. the modulation scheme and coding
`rate) used for DL-SCH transmission to the specific UE in the
`given subframe. Separate DL-SCH transmissions, using
`different physical resources (different resource blocks), can
`be carried out to different UEs during the same subframe. In
`this case there are multiple L1/L2 control channels, one for
`each UE that is to receive DL-SCH transmission in the given
`subframe.
`
`50
`
`55
`
`60
`
`65
`
`2
`In addition to user data, System information is also
`transmitted on the downlink within each cell. The system
`information may, e.g., include: public Land Mobile Network
`(PLMN) identity/identities, identifying the operator(s) to
`which the cell “belongs: Neighbor-cell list, i.e. a list of the
`cells that are neighbors to the current cell; and different
`parameters used by the user terminal when accessing the
`system, e.g. random-access parameters and cell-access
`restrictions. The system information can be divided into two
`parts, one part being fixed and the other part being dynamic.
`The fixed part of the system information is transmitted on a
`pre-determined physical resource, i.e. a specific set of
`OFDM subcarriers during a specific time interval, using a
`pre-determined transport format. There is thus no flexibility
`in the amount of information in the fixed part of the system
`information. There is also no flexibility in the transmission
`structure (the physical resource and the transport format)
`used for the fixed part of the system information. In LTE, the
`fixed part of the system information is transmitted using the
`BCH (broadcast control channel) transport channel. Further
`more, for LTE it is currently assumed that the BCH is
`transmitted in the six centre resource blocks in subframe #0
`of each frame.
`The dynamic part of the system information is assumed to
`be transmitted using the DL-SCH, or at least a DL-SCH-like
`transport channel, similar to normal data transmission as
`described above. New UEs continuously “enter the cell,
`either entering from a neighbor cell, due to power-on, or
`upon return from out-out-service, and the UEs must quickly
`acquire the system information. Thus the system informa
`tion (both the fixed part on the BCH and the dynamic part
`on the DL-SCH or a DL-SCH-like channel) should be
`repeated regularly.
`As an example, in LTE the fixed part of the system
`information (transmitted using the BCH) is assumed to be
`repeated every 40 ms. Also the dynamic part of the system
`information should be repeated more or less regularly.
`However, different portions of the dynamic part of the
`system information are more or less time critical, in the
`sense of how quickly the UE must acquire it, and thus need
`to be repeated more or less often. This can be described so
`that the dynamic part of the system information is divided
`into different so-called scheduling units, also referred to as
`System Information Messages. In general, information cor
`responding to scheduling unit number n should be repeated
`more often than information corresponding to scheduling
`unit number n+1. As an example, Scheduling unit #1 (SU-1)
`may be repeated (approximately) once every 80 ms, sched
`uling unit #2 (SU-2) may be repeated (approximately) once
`every 160 ms, scheduling unit #3 (SU-3) may be repeated
`(approximately) once every 320 ms, etc.
`
`SUMMARY
`
`The invention described below allows for transmission of
`the dynamic part of the system information fulfilling these
`requirements and desirable properties while, at the same
`time, allowing for low UE complexity. One aspect of the
`teachings presented herein is to transmit system information
`in regularly occurring (system information) windows, with
`specific RNTIs indicating the presence of system informa
`tion in a subframe, and with another specific RNTI indicat
`ing the end of system information transmission. This enables
`UES to stop receiving, demodulating and decoding Sub
`frames when no more system information is expected during
`the current window.
`
`ERICSSON EXHIBIT 2008
`Apple, Inc. v. Telefonaktiebolaget LM Ericsson
`IPR2022-00338, Page 9
`
`

`

`US 9,532,355 B2
`
`3
`In one embodiment, a method of transmitting system
`information on a downlink shared channel structured as
`Successive subframes includes transmitting system informa
`tion in regularly occurring time windows, each time window
`spanning some number of Successive subframes. The
`method further includes indicating to receiving user equip
`ment which subframes within a given time window carry
`system information.
`Of course, the present invention is not limited to the above
`features and advantages. Indeed, those skilled in the art will
`recognize additional features and advantages upon reading
`the following detailed description, and upon viewing the
`accompanying drawings.
`
`5
`
`10
`
`4
`one of the scheduling units 132 could be transmitted within
`every fourth window, and so on.
`In one embodiment, the transmission timing correspond
`ing to each scheduling unit 132 can be pre-specified when a
`limited amount of transmission periods are employed by the
`network 100. In another embodiment, the window transmis
`sion timing can be signaled to the UE 120, e.g. when more
`specific values for transmitted scheduling units 132 are
`specified. Either way, a variable window size can be used if
`the amount of system information is not the same in each
`window. In one embodiment, the window size is increased
`when system information from additional scheduling units
`132 is transmitted.
`FIG. 3 illustrates one embodiment of transmitting the
`dynamic (possibly changing) system information within
`regularly occurring windows with well-defined starting
`points (specific subframes) and of a certain size in number
`of (consecutive) Subframes. In the illustration, the system
`information windows, more generally regarded as recurring
`time windows defined for the transmission of system infor
`mation, start at subframe #5 of the frame with frame number
`8*k and have a size of 13 subframes. The network trans
`mitter 110 only transmits the dynamic part of the system
`information within these windows. Moreover, the window
`occurs (is repeated) often enough to fulfill the repetition rate
`of the most often repeated system information (in LTE
`terminology, system information corresponding to the first
`scheduling unit 132, as described above).
`In one or more embodiments, within each recurring time
`window, the transmission of system information is carried
`out similar to the transmission of user data on DL-SCH
`(dynamic resource and transport format with signaling on
`L1/L2 control channel), with some exceptions. Instead of
`using an RNTI of a specific UE 120, a specific System
`Information RNTI (SI-RNTI), indicating that system infor
`mation to be read by all UEs 120 is being transmitted, is
`included in the corresponding L1/L2 control signaling. Also,
`for the last piece of system information to be transmitted
`within the window, the SI-RNTI is replaced with an End
`of-System-Information RNTI (ESI-RNTI). The reception of
`an ESI-RNTI informs the UE 120 that no more system
`information is transmitted within the window. The UE 120
`can stop demodulating and decoding the L1/L2 control
`channel when there is no more system information to be
`transmitted in the window, thus improving UE power-saving
`performance.
`Moreover, the system information does not have to be
`transmitted in consecutive subframes. This way, the network
`transmitter 110 can dynamically avoid transmitting system
`information in certain subframes when a more pressing need
`for subframes arises, e.g., when a subframe is needed for
`high priority downlink data transmission or for uplink
`transmission in case of TDD. In addition, the set of Sub
`frames in which system information is actually transmitted
`does not have to be the same between consecutive windows.
`Furthermore, the network transmitter 110 can dynamically
`vary the number of subframes used to carry system infor
`mation without prior knowledge of the UE 120 (i.e., prior to
`the UE 120 reading the L1/L2 control channel).
`As non-limiting examples, the teachings presented herein
`for transmitting system information yields several desirable
`properties. For example, there are several requirements and
`desired properties for the transmission of the dynamic part
`of the system information. From a UE power-consumption
`point of-view, it is desirable to transmit the different parts of
`the system information as close in time as possible to each
`other, in the ideal case in a set of consecutive subframes.
`
`BRIEF DESCRIPTION OF THE DRAWINGS
`
`15
`
`FIG. 1 is a block diagram of an embodiment of a wireless
`network that overlays or otherwise defines a recurring
`sequence of time windows for the transmission of dynamic
`system information using Subframes falling within the
`defined time windows.
`FIG. 2 is a diagram of an embodiment of different
`system-information time windows having different repeti
`tion periods.
`FIG. 3 is a diagram of an embodiment of overlaying or
`otherwise defining a recurring sequence of time windows for
`the transmission of dynamic system information using Sub
`frames falling within the defined time windows.
`FIG. 4 is a flow diagram of an embodiment of program
`logic for overlaying or otherwise defining a recurring
`sequence of time windows for the transmission of dynamic
`system information using subframes falling within the
`defined time windows.
`FIG. 5 is a flow diagram of an embodiment of program
`logic for processing recurring system-information time win
`dows containing dynamic system information included in
`subframes falling within the defined time windows.
`FIG. 6 is a diagram of an embodiment of variably sized
`recurring system-information time windows for the trans
`mission of system information.
`FIG. 7 is a diagram of an embodiment of different
`system-information time windows.
`
`25
`
`30
`
`35
`
`40
`
`DETAILED DESCRIPTION
`
`45
`
`FIG. 1 illustrates an embodiment of a wireless network
`100 including one or more network transmitters 110 such as
`a radio base station which services one or more UEs 120.
`The network transmitter 110 includes a baseband processor
`130 for generating one or more scheduling units 132 (also
`referred to as System Information Messages) including
`dynamic parts of the system information. The network
`transmitter 110 sends the scheduling units 132 to the UE 120
`using different system-information windows. In one
`embodiment, the system-information windows occur with a
`period corresponding to the repetition period of the most
`frequently occurring scheduling unit 132 as shown in FIG.
`2 where “SU-n” refers to the nth scheduling unit 132.
`System information corresponding to the most frequently
`occurring scheduling unit 132 is transmitted within each
`system-information window while less frequently-occurring
`scheduling units 132 are transmitted only within a sub-set of
`the system-information windows, where system information
`is shown as a shaded area in FIG. 2. For illustrative purposes
`only, system information corresponding to a second one of
`the scheduling units 132 could be transmitted within every
`second window, system information corresponding to a third
`
`50
`
`55
`
`60
`
`65
`
`ERICSSON EXHIBIT 2008
`Apple, Inc. v. Telefonaktiebolaget LM Ericsson
`IPR2022-00338, Page 10
`
`

`

`5
`This enables the UE 120 to receive the maximum amount of
`system information during a minimum reception time,
`reducing UE reception time and UE power consumption.
`The teachings herein also allow system information to be
`transmitted in recurring time windows, where the particular
`Subframes within each window used for carrying system
`information are selectable. If current conditions, e.g., com
`peting transmission priorities permit, the system information
`can be transmitted in a contiguous set of Subframes within
`the time window.
`It is also desirable to have flexibility in terms of exactly
`where the system information is transmitted, i.e., exactly
`which set of subframes within a given time window carries
`the system information. Some subframes, depending on the
`situation, may not be available for transmitting system
`information. For example, some TDD subframes may not be
`available for downlink transmission. In another example, for
`latency reasons there may, in Some situations, be a benefit to
`not having too many consecutive subframes used for trans
`mission of system information, thus making them unavail
`able for downlink user data transmission. As such, it is also
`desirable to dynamically (with low delay) decide in exactly
`what subframes the system information is to be transmitted.
`Further, it is desirable to have flexibility in the rate by
`which different parts of the system information is repeated.
`In this way, a higher repetition rate (shorter repetition
`period) can be used, e.g. in the case of wider overall
`transmission bandwidth, when the overhead of the system
`information transmission is less of a concern. It is desirable
`to have flexibility in the number of subframes used to
`transmit the system information. As an example, in case of
`smaller overall bandwidth or larger cells, more subframes
`may be needed to transmit a given set of system information.
`Moreover, the amount of system information, e.g. neighbor
`lists and PLMN lists may be of different sizes for different
`cells.
`The teachings presented herein provide for methods and
`apparatuses where system information is transmitted within
`recurring time windows, but with flexible selection of which
`Subframes within those windows are used to carry System
`information. FIG. 4 illustrates one embodiment of program
`logic for transmitting system information from the network
`transmitter 110 to the UE 120. According to this embodi
`ment, the baseband processor 130 included in the network
`transmitter 110 initializes the first subframe in the system
`information window (Step 400). The baseband processor
`130 then determines whether the current subframe is to be
`used for transmission of system information (Step 402). If
`so, the baseband processor 130 determines whether the
`current subframe is the last subframe in the window (Step
`404). If the current subframe is the last subframe, the RNTI
`of the L17L2 control channel is set to ESI-RNTI for indi
`cating to the UE 120 that the subframe is the last subframe
`in the window containing system information. (Step 406).
`Otherwise, the control channel RNTI is set to SI-RNTI for
`indicating to the UE 120 that the subframe contains system
`information, but is not the last subframe. (Step 408). The
`corresponding system information is transmitted on the
`DL-SCH within the current subframe (Step 410). The base
`band processor 130 determines whether the last window
`subframe has been transmitted (Step 412). If not, Steps
`402-412 are repeated for the next subframe within the
`window. The system information transmission process ends
`when the last subframe is transmitted (Step 416).
`FIG. 5 illustrates one embodiment of program logic
`carried out by the UE 120 for processing the system infor
`mation transmitted by the network transmitter 110. Accord
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`ing to this embodiment, the UE 120 includes a baseband
`processor 140 for demodulating and decoding received
`subframes. A window detection and evaluation unit 150
`included in or associated with the baseband processor 140
`begins the window reception process by initializing the first
`subframe received within the window (Step 500). The
`baseband processor 150 then demodulates and decodes the
`L1/L2 control channel of the current subframe (Step 502).
`The window detection and evaluation unit 150 determines
`whether either SI-RNTI or ESI-RNTI is detected for the
`current subframe (Step 504). If so, the baseband processor
`140 demodulates and decodes the corresponding DL-SCH
`transport block to retrieve the system information provided
`therewith (Step 506). The window detection and evaluation
`unit 150 then determines whether the current subframe is the
`last Subframe in the window or the last subframe containing
`system information, e.g., whether the RNTI of the control
`channel is ESI-RNTI (Step 508). If neither condition exists,
`Steps 502-508 are repeated for the next subframe within the
`window (Step 510). The baseband processor 140 stops
`demodulating and decoding DL-SCH transport blocks when
`either the last subframe or ESI-RNTI is detected, indicating
`no more system information is forthcoming (Step 512).
`Thus, the UE 120 demodulates and decodes the control
`channel starting with the first subframe in the system infor
`mation window and checks for specific system information
`RNTIS until either the ESI-RNTI is detected or the last
`window subframe is received.
`As discussed above, Some parts of the system information
`(corresponding to the scheduling units 132) may not need to
`be repeated as often as some other parts of the system
`information, implying that certain windows will include
`more data (more scheduling units 132) than other windows.
`Thus, the window size may be of varying length, with a
`longer window at the time instances where more system
`information (more scheduling units 132) is to be transmitted.
`FIG. 6 provides an illustration of a variable-length window
`embodiment.
`Note that the window size can be specified in either the
`radio-access specification or be configurable. In case of a
`configurable window size, the UE 120 can use a default
`(large) window size before it is informed (via the system
`information) about the actual window size. Moreover, the
`RNTI may indicate more than just system information such
`as more details about the system information. In one
`embodiment, several different SI-RNTIs could be used, e.g.,
`SI-RNTI1, SI-RNTI2, SI-RNTI3, . . . . with corresponding
`multiple ESI-RNTIs, e.g., ESI-RNTI1, ESI-RNTI2, ESI
`RNTI3, etc.
`In one embodiment, the scheduling units 132 transmitted
`at the same time use the same system-information window
`as shown in the upper part of FIG. 7. Alternatively, the
`scheduling units 132 are transmitted using different system
`information windows as shown in the lower part of FIG. 7.
`In either embodiment, system information is transmitted in
`regularly occurring system-information windows, with spe
`cific RNTIs indicating the presence of system information in
`a subframe, and with another specific RNTI indicating the
`end of system information transmission.
`Of course, other variations are contemplated. Thus, the
`foregoing description and the accompanying drawings rep
`resent non-limiting examples of the methods and apparatus
`taught herein for the transmission of system information. As
`Such, the present invention is not limited by the foregoing
`description and accompanying drawings. Instead, the pres
`ent invention is limited only by the following claims and
`their legal equivalents.
`
`ERICSSON EXHIBIT 2008
`Apple, Inc. v. Telefonaktiebolaget LM Ericsson
`IPR2022-00338, Page 11
`
`

`

`What is claimed is:
`1. A method of transmitting system information on a
`downlink shared channel of a wireless communication net
`work comprising:
`transmitting system information on the downlink shared
`channel in recurring time windows, each time window
`spanning one or more subframes,
`wherein a set of subframes out of the one or more
`Subframes within a time window is used for carrying
`the system information; and
`using an indicator in each subframe in the set of Sub
`frames that is used for carrying the system information
`to indicate to receiving user equipment that the Sub
`frame carries system information, wherein the indicator
`is a System Information Radio Network Temporary
`Identifier (SI-RNTI).
`2. The method of claim 1, wherein the set of subframes
`within the time window is a contiguous set of Subframes
`within the time window.
`3. The method of claim 1, wherein the set of subframes
`within the time window is a non-contiguous set of Subframes
`within the time window.
`4. The method of claim 1, wherein the set of subframes
`within the time window used for carrying the system infor
`mation is dynamically selected in view of competing trans
`mission priorities associated with other control or data
`signaling.
`5. The method of claim 1, wherein using an indicator in
`each subframe in the set of subframes that is used for
`carrying the system information to indicate to receiving user
`equipment that the subframe carries system information
`includes using an end-of-system-information indicator in a
`last subframe of the time window that carries system infor
`mation.
`6. The method of claim 1, further comprising varying
`window sizes of the recurring time windows.
`7. The method of claim 1, further comprising dynamically
`configuring a window size for the recurring time windows.
`8. The method of claim 1, wherein using an indicator in
`each subframe in the set of subframes that is used for
`carrying the system information to indicate to receiving user
`equipment that the subframe carries system information
`includes using different indicators corresponding to different
`types of system information, Such that the indicator used for
`a particular subframe indicates the type of system informa
`tion carried in that subframe.
`9. The method of claim 1, wherein the wireless commu
`nication network is an Orthogonal Frequency Division Mul
`tiplexing (OFDM) based wireless communication network.
`10. A network transmitter comprising a baseband proces
`Sor configured to:
`generate system information for transmission on a down
`link shared channel in recurring time windows, each
`time window spanning one or more subframes, wherein
`a set of subframes out of the one or more subframes
`within a time window is used for carrying the system
`information; and
`use an indicator in each Subframe in the set of subframes
`that is used for carrying the system information to
`indicate to receiving user equipment that the subframe
`carries system information, wherein the indicator is a
`System Information Radio Network Temporary Iden
`tifier (SI-RNTI).
`11. The network transmitter of claim 10, wherein the
`network transmitter comprises a radio base station config
`ured for operation in accordance with 3GPPE-UTRA stan
`dards.
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`12. The network transmitter of claim 10, wherein the
`network transmitter is configured for operation in an
`Orthogonal Frequency Division Multiplexing (OFDM)
`based wireless communication network.
`13. A method of transmitting system information on a
`downlink shared channel structured as successive Sub
`frames, the method comprising:
`transmitting system information in regularly occurring
`time windows, each time window spanning some num
`ber of successive subframes; and
`indicating to receiving user equipment which subframes
`within the time windows carry system information, by
`using an indicator in each subframe within the time
`windows that carries system information.
`14. The method of claim 13, further comprising dynami
`cally selecting which subframes within the time windows
`are used for carrying system informa