US008457676B2
`
`(12) United States Patent
`Michel et al.
`
`(10) Patent N0.:
`(45) Date of Patent:
`
`US 8,457,676 B2
`Jun. 4, 2013
`
`(54)
`
`(75)
`
`POWER HEADROOM REPORTING METHOD
`
`Inventors: Juergen Michel, Miinchen (DE); Klaus
`Ingemann Pedersen, Aalborg (DK);
`Claudio Rosa, Randers (DK)
`
`(73)
`
`Assignee: Nokia Siemens Networks Oy, Espoo
`(F1)
`
`Notice:
`
`Subject to any disclaimer, the term of this
`patent is extended or adjusted under 35
`U.S.C. 154(b) by 396 days.
`
`(21)
`
`Appl. N0.:
`
`12/665,427
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`(22)
`
`(86)
`
`(87)
`
`(65)
`
`(60)
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`(51)
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`(52)
`
`PCT Filed:
`
`Jun. 23, 2008
`
`PCT No.:
`
`PCT/FI2008/050384
`
`§ 371 (0X1)’
`(2), (4) Date:
`
`Jan. 22, 2010
`
`PCT Pub. No.: WO2008/155469
`
`PCT Pub. Date: Dec. 24, 2008
`
`Prior Publication Data
`
`US 2010/0173665 A1
`
`Jul. 8, 2010
`
`Related US. Application Data
`
`Provisional application No. 60/936,649, ?led on Jun.
`20, 2007.
`
`Int. Cl.
`H04B 7/00
`US Cl_
`USPC .............................. .. 455/522; 455/68; 455/69
`
`(2006.01)
`
`(58) Field of Classi?cation Search
`USPC ............. .. 455/522, 67.11, 68470, 115.3, 126,
`455/127.1, 127.2, 135, 226.3, 277.2, 296;
`370/318
`See application ?le for complete search history.
`References Cited
`
`(56)
`
`U.S. PATENT DOCUMENTS
`
`6/1999 Tiedemann et al. ........ .. 370/348
`5,914,950 A *
`7/2009 Cho et al. ...................... .. 455/69
`7,558,535 B2 *
`2/2003 Li et al.
`2003/0026324 A1
`2004/0252658 A1* 12/2004 Hosein et al. ............... .. 370/328
`2007/0015476 A1* 1/2007 Akbar Attar et a1.
`455/127.1
`2007/0097962 A1* 5/2007 Yoon et al. ....... ..
`370/352
`2007/0270175 A1* 11/2007 Malladi et al. .............. .. 455/522
`(Continued)
`FOREIGN PATENT DOCUMENTS
`1 311 076 A1
`5/2003
`1 628 413 A2
`2/2006
`WO 00/03499
`1/2000
`WO 00/62441
`10/2000
`OTHER PUBLICATIONS
`
`EP
`EP
`W0
`W0
`
`3GPP TS 36.300 V8.0.0 (Mar. 2007); 3rd Generation Partnership
`Project; Technical Speci?cation Group Radio Access Network;
`Evolved Universal Terrestrial Radio Access (E-UTRA) and Evolved
`Universal Terrestrial Radio Access Network (E-UTRAN); Overall
`Description; Stage 2 (Release 8).
`Primary Examiner * Dominic E Rego
`(74) Attorney, Agent, or Firm * Harrington & Smith
`(57)
`ABSTRACT
`A method, user equipment, network device, and software
`product enable a user equipment to determine that at least one
`of several triggering criterion have been met, in which case
`the user equipment provides a power control headroom report
`on an uplink from the user equipment. The triggering crite
`rion includes a threshold having been reached, and the thresh
`old is adjustable via a signal to the user equipment from a base
`station (such as an eNodeB).
`35 Claims, 4 Drawing Sheets
`
`I
`
`Core Network
`
`(ON)
`
`Iu
`
`104
`
`Iu
`
`126
`
`I
`
`UE Gives Power Control
`Report if Adjustable
`Criteria Are Met
`
`Apple Inc. v. Cellular Communications Equipment LLC
`APPL-1001 / Page 1 of 11
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`

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`US 8,457,676 B2
`Page 2
`
`US. PATENT DOCUMENTS
`2008/0233992 A1*
`2008/0240013 A1*
`2008/0247358 A1*
`2008/0259833 A1*
`
`9/2008 Oterietal. .................. .. 455/522
`10/2008 Johnson et a1.
`. 370/315
`10/2008 Damnjanovic et a1. ..... .. 370/329
`10/2008 Ozturketal. ............... .. 370/310
`
`2009/0034479 A1*
`2010/0029212 A1*
`2010/0046481 A1*
`
`2/2009 Wakayama et a1. ......... .. 370/332
`2/2010 Malladi et a1. ..
`455/631
`2/2010 Chen et a1. .................. .. 370/335
`
`* cited by examiner
`
`APPL-1001 / Page 2 of 11
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`APPL-1001 / Page 3 of 11
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`Jun. 4, 2013
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`Sheet 3 of4
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`US 8,457,676 B2
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`Adjusting a threshold at UE by signalling from base
`station.
`
`8)
`
`Determining at UE that a triggering criterion has been
`
`met because the threshold has been reached. 2)
`Providing power control headroom report on uplink. g)
`
`V
`
`Receiving report at base station.
`
`Providing closed loop power control correction
`command to UE
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`APPL-1001 / Page 5 of 11
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`APPL-1001 / Page 6 of 11
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`APPL-1001 / Page 6 of 11
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`

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`US 8,457,676 B2
`
`1
`POWER HEADROOM REPORTING METHOD
`
`CROSS-REFERENCE TO RELATED
`APPLICATIONS
`
`This application claims the bene?t of Provisional Applica
`tion No. 60/936,649, ?led Jun. 20, 2007, the disclosure of
`Which is incorporated herein by reference in its entirety.
`
`FIELD OF THE INVENTION
`
`The invention relates to the ?eld of Wireless telecommuni
`cations. More particularly, the present invention pertains to
`poWer control.
`
`BACKGROUND OF THE INVENTION
`
`The telecommunications industry is in the process of
`developing a neW generation of ?exible and affordable com
`munications that includes high-speed access While also sup
`porting broadband services. Many features of the third gen
`eration (3G) mobile telecommunications system have already
`been established, but many other features have yet to be
`perfected. The Third Generation Partnership Project (3GPP)
`has been pivotal in these developments.
`One of the systems Within the third generation of mobile
`communications is the Universal Mobile Telecommunica
`tions System (UMTS) Which delivers voice, data, multime
`dia, and Wideband information to stationary as Well as mobile
`customers. UMTS is designed to accommodate increased
`system capacity and data capability. E?icient use of the elec
`tromagnetic spectrum is vital in UMTS. It is known that
`spectrum ef?ciency can be attained using frequency division
`duplex (FDD) or using time division duplex (TDD) schemes.
`Space division duplex (SDD) is a third duplex transmission
`method used for Wireless telecommunications.
`As canbe seen in FIG. 1, the UMTS architecture consists of
`user equipment 102 (UE), the UMTS Terrestrial Radio
`Access NetWork 104 (UTRAN), and the Core NetWork 126
`(CN). The air interface betWeen the UTRAN and the UE is
`called Uu, and the interface betWeen the UTRAN and the
`Core NetWork is called Iu.
`High-Speed DoWnlink Packet Access (HSDPA) and High
`Speed Uplink Packet Access (HSUPA) are further 3G mobile
`telephony protocols in the High-Speed Packet Access
`(HSPA) family. They provide a smooth evolutionary path for
`UMTS-based netWorks alloWing for higher data transfer
`speeds.
`Evolved UTRAN (EUTRAN) is a more recent project than
`HSPA, and is meant to take 3G even farther into the future.
`EUTRAN is designed to improve the UMTS mobile phone
`standard in order to cope With various anticipated require
`ments. EUTRAN is frequently indicated by the term Long
`Term Evolution (LTE), and is also associated With terms like
`System Architecture Evolution (SAE). One target of
`EUTRAN is to enable all intemet protocol (IP) systems to
`e?iciently transmit IP data. The system Will have only use a
`PS (packet sWitched) domain for voice and data calls, ie the
`system Will contain Voice Over Internet Protocol (VoIP).
`Information about LTE can be found in 3GPP TS 36.300
`(V8.0.0, March 2007), Evolved Universal Terrestrial Radio
`Access (E-UTRA) and Evolved Universal Terrestrial Radio
`Access Network (E- UTRAN)iOverall description; Stage 2
`(Release 8), Which is incorporated herein by reference in its
`entirety. UTRAN and EUTRAN Will noW be described in
`some further detail, although it is to be understood that espe
`cially E-UTRAN is evolving over time.
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`The UTRAN consists of a set of Radio NetWork Sub
`systems 128 (RNS), each of Which has geographic coverage
`ofa number of cells 110 (C), as can be seen in FIG. 1. The
`interface betWeen the subsystems is called Iur. Each Radio
`NetWork Subsystem 128 (RNS) includes a Radio NetWork
`Controller 112 (RNC) and at least one Node B 114, each
`Node B having geographic coverage of at least one cell 110.
`As can be seen from FIG. 1, the interface betWeen an RNC
`112 and a Node B 114 is called Iub, and the Iub is hard-Wired
`rather than being an air interface. For any Node B 114 there is
`only one RNC 112. A Node B 114 is responsible for radio
`transmission and reception to and from the UE 102 (Node B
`antennas can typically be seen atop toWers or preferably at
`less visible locations). The RNC 112 has overall control of the
`logical resources of each Node B 114 Within the RNS 128,
`and the RNC 112 is also responsible for handover decisions
`Which entail sWitching a call from one cell to another or
`betWeen radio channels in the same cell.
`In UMTS radio netWorks, a UE can support multiple appli
`cations of different qualities of service running simulta
`neously. In the MAC layer, multiple logical channels can be
`multiplexed to a single transport channel. The transport chan
`nel can de?ne hoW traf?c from logical channels is processed
`and sent to the physical layer. The basic data unit exchanged
`betWeen MAC and physical layer is called the Transport
`Block (TB). It is composed of an RLC PDU and a MAC
`header. During a period of time called the transmission time
`interval (TTI), several transport blocks and some other
`parameters are delivered to the physical layer.
`Generally speaking, a pre?x of the letter “E” in upper or
`loWer case signi?es the Long Term Evolution (LTE). The
`E-UTRAN consists of eNBs (E-UTRAN Node B), providing
`the E-UTRA user plane (RLC/MAC/PHY) and control plane
`(RRC) protocol terminations toWards the UE. The eNBs
`interface to the access gateWay (aGW) via the S1, and are
`inter-connected via the X2.
`An example of the E-UTRAN architecture is illustrated in
`FIG. 2. This example of E-UTRAN consists of eNBs, provid
`ing the E-UTRA user plane (RLC/MAC/PHY) and control
`plane (RRC) protocol terminations toWards the UE. The
`eNBs are connected by means of the S1 interface to the EPC
`(evolved packet core), Which is made out of Mobility Man
`agement Entities (MMEs) and/or gateWays such as an access
`gateWay (aGW). The S1 interface supports a many-to-many
`relation betWeen MMEs and eNBs. Packet Data Convergence
`Protocol (PDCP) is located in an eNB.
`In this example there exists an X2 interface betWeen the
`eNBs that need to communicate With each other. For excep
`tional cases (eg inter-PLMN handover), LTE_ACTIVE
`inter-eNB mobility is supported by means of MME relocation
`via the S1 interface.
`The eNB may host functions such as radio resource man
`agement (radio bearer control, radio admission control, con
`nection mobility control, dynamic allocation of resources to
`UEs in both uplink and doWnlink), selection of a mobility
`management entity (MME) at UE attachment, scheduling and
`transmission of paging mes sages (originated from the MME),
`scheduling and transmission of broadcast information (origi
`nated from the MME or O&M), and measurement and mea
`surement reporting con?guration for mobility and schedul
`ing. The MME may host functions such as the folloWing:
`distribution of paging messages to the eNBs, security control,
`IP header compression and encryption of user data streams,
`termination of U-plane packets for paging reasons; sWitching
`of U-plane for support of UE mobility, idle state mobility
`control, System Architecture Evolution (SAE) bearer control,
`and ciphering and integrity protection of NAS signaling.
`
`APPL-1001 / Page 7 of 11
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`3
`In mobile telecommunications, the two basic types of
`power control are open-loop and closed-loop. In open-loop
`power control (OLPC), a mobile terminal measures received
`pilot signal power and accordingly sets the transmission
`power density (PDS) according to this measured quantity, and
`based on the pilot transmitted power, the S(I)NR target, and
`the interference level (these last values are usually broad
`casted by the base station). In closed-loop power control, the
`measurements are done on the other end of the connection, in
`the base station, and the results are then sent back to the
`mobile terminal so that the mobile terminal can adjust its
`transmission power. Note that the term “base station” is used
`broadly in this application, and may refer to a Node B, or an
`eNodeB, or the like.
`The current trend in the art is that uplink power control will
`include: (i) an open loop power control mechanism at the
`terminal, as well as (ii) options for the eNode-B to send closed
`loop power control correction commands to the terminal. The
`current invention solves problems that occur with uplink
`power control and associated signalling from the terminal to
`the base station (eNode-B) to facilitate e?icient uplink radio
`resource management decisions at the eNode-B.
`Given this uplink power control scheme, the eNode-B may
`be unaware of the transmit power level at which different
`terminals are operating. This information is important for the
`eNode-B, because this knowledge is needed for optimal radio
`resource management decisions such as allocating MCS
`(modulation and coding scheme) and transmission band
`width for the different terminals. It therefore has been dis
`cussed in 3GPP that terminals should be able to provide
`power control headroom reports to the eNode-B. The power
`control headroom report basically provides a measure of how
`close the ter'minal’s power spectral density (PSD) is to the
`maximum PSD limit. The maximum PSD might be derived
`from the maximum UE transmit power (typically assumed to
`be on the order of 24 dBm) and the minimum bandwidth
`(typically 1 PRB).
`Unfortunately, 3GPP has not yet been able to ?nd satisfac
`tory criteria for sending a power control headroom report
`from the user terminal to the eNode-B. In LTE uplink (UL),
`the eNode-B makes the scheduling and radio resource man
`agement decisions such as selecting the UEs to transmit,
`allocating the UE transmission bandwidths, and (as men
`tioned above) selecting the MCS they should use. These
`decisions are then signalled to the ter'minal(s) via dedicated
`signalling (e.g. UL scheduling grant message). And, in order
`to make these decisions properly, the eNode-B should be
`aware of the power level at which the terminals are transmit
`ting, or some equivalent information like the power headroom
`information, since from this information the eNodeB derives
`which MCS can be supported in the future with a targeted
`block error rate (BLER) which would be otherwise not pos
`sible. Knowing at the eNode-B the power spectral density
`used by the mobile terminals is particularly important when
`selecting the transmission bandwidth (rather than the MCS).
`Not knowing with precision the PSD used by a mobile termi
`nal when selecting the MCS has only a major impact in case
`of slow AMC (in which case the PSD is “automatically”
`increased/ decreased when the MCS is modi?ed).
`Consequently, reporting of power headroom or some
`equivalent information is needed. However, reporting of the
`power control headroom is a trade-off between uplink signal
`ling overhead versus performance improvements that result
`from having this information readily available at the eNode
`B.
`It is problematic to have the terminal periodically report the
`power control headroom at a frequency higher than the
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`adjustments of the actual terminal power spectral density
`(PSD). Further, the aim of these power adjustments at the
`terminal is basically to (partly or fully) compensate the path
`loss (including antenna-pattem, distance dependent path-loss
`and shadowing) between the eNode-B and the terminal, and
`the measurement of path-loss is done based on the DL (e.g.
`DL pilot channel). Even if the frequency of potential power
`adjustments at the terminal is high but the measured path-loss
`is not changing, UL signalling would be a waste of resources;
`the only issue then for reporting would be if closed loop
`power control commands would come from the eNodeB and
`some of those commands would be misinterpreted at the UE.
`Then, the problem occurs that the eNodeB does not know the
`used transmission power. The problem with power control
`commands being misinterpreted at the mobile terminal is
`only an issue if relative closed loop power control commands
`are used (which is also the working assumption in 3GPP).
`In HSUPA, the UE Power Headroom (UPH) is part of the
`Scheduling Information (SI), which is transmitted by the UE
`as part of the MAC-e header. If the UE is not allocated
`resources for the transmission of scheduled-data, then Sched
`uling Information can be transmitted periodically and/or
`based on speci?c triggers (i.e. when data arrives in the buffer).
`Otherwise, only periodic reporting is supported.
`
`SUMMARY OF THE INVENTION
`
`Although the present invention is applicable in the context
`of the E-UTRAN (LTE or 3 .9G), its principles are not limited
`to such an environment, and instead may also be applicable to
`various other current and future wireless telecommunications
`systems and access technologies. This invention provides
`speci?c reporting criteria that are an attractive trade-off
`between signalling overhead versus overall uplink perfor
`mance for LTE. The following triggering criteria are found to
`be very ef?cient for sending a power control headroom report
`in the uplink, while optimiZing uplink performance, and
`while minimiZing signalling overhead.
`The ?rst triggering criterion is that, once “n” closed loop
`power corrections have been received by a terminal (sent
`from the eNode-B), the power control headroom is measured
`by the terminal over the next “m” transmission time intervals
`(TTIs) and afterwards reported to the eNode-B. The reason
`for this ?rst criterion is, as already mentioned above, that the
`closed loop commands can be misinterpreted at the terminal
`and therefore tracking of power status at the eNodeB would
`lead to the accumulation of such errors. The problem with
`power control commands being misinterpreted at the mobile
`terminal is only an issue if relative closed loop power control
`commands are used (which is also the working assumption in
`3GPP).
`The second triggering criterion is that, after the ter'minal’s
`open loop power control algorithm modi?es the PSD, the
`terminal shall measure the power control headroom over the
`following “m” TTIs and afterwards report it to the eNode-B.
`The third triggering criterion is that, in order to further limit
`the signalling of uplink power control headroom reports, the
`terminal shall only send a new power control headroom report
`if the time since the last reporting exceeds “k” TTIs.
`And, the fourth triggering criterion is that, instead of the
`third triggering criterion, another embodiment of the inven
`tion is that the terminal shall only send a new power control
`headroom report if the absolute difference between the cur
`rent and the latest path-loss measurement is higher than a
`given threshold “p”.
`The three aforementioned quantities “n”, “m”, “k” (or “p”
`if the fourth rather than third triggering criterion is used) are
`
`APPL-1001 / Page 8 of 11
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`US 8,457,676 B2
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`5
`parameters that are con?gured by the eNode-B. As an
`example, these parameters can be con?gured via RRC sig
`nalling from the eNode-B to the terminal. These described
`triggering criteria can be combined (eg using a logical “OR”
`combination).
`
`BRIEF DESCRIPTION OF THE DRAWINGS
`
`FIG. 1 shoWs a UTRAN netWork.
`FIG. 2 shoWs an LTE architecture.
`FIG. 3 is a How chart shoWing and embodiment of a method
`according to the present invention.
`FIG. 4 is a block diagram of a system according to an
`embodiment of the present invention.
`
`DETAILED DESCRIPTION OF THE INVENTION
`
`6
`the CPU, the memory may reside at a single physical location,
`comprising one or more types of data storage, or be distrib
`uted across a plurality of physical systems in various forms.
`It is to be understood that the present ?gures, and the
`accompanying narrative discussions of best mode embodi
`ments, do not purport to be completely rigorous treatments of
`the method, system, mobile device, netWork element, and
`softWare product under consideration. A person skilled in the
`art Will understand that the steps and signals of the present
`application represent general cause-and-effect relationships
`that do not exclude intermediate interactions of various types,
`and Will further understand that the various steps and struc
`tures described in this application can be implemented by a
`variety of different sequences and con?gurations, using vari
`ous different combinations of hardWare and softWare Which
`need not be further detailed herein.
`The invention includes a variety of concepts, Which can be
`brie?y described as folloWs, Without in any Way limiting What
`Will be claimed in the future in reliance upon this provisional
`application. It is to be understood that the folloWing concepts
`can be further combined With each other in any multiple
`dependent manner, Without departing from the scope of the
`invention.
`
`The invention claimed is:
`1. A method comprising:
`determining that a set of at east one triggering criterion is
`met; and
`providing a poWer control headroom report on an uplink
`from user equipment, in response to determining that the
`set is met, Wherein said at least one triggering criterion
`include at least one threshold having been reached,
`Wherein said at least one threshold is adjustable via a
`signal to the user equipment, Wherein the set of at least
`one triggering criterion comprises a criterion being met
`based on reaching a threshold of the at least one thresh
`old of k transmission time intervals folloWing a previous
`poWer control headroom report, Wherein k is an integer
`and Wherein said at least one threshold adjustable via the
`signal comprises adjusting the threshold integer k.
`2. The method of claim 1, Wherein said poWer control
`headroom report is for use in a poWer control correction
`command to the user equipment.
`3. The method of claim 1, Wherein the set of at least one
`triggering criterion comprises a triggering criterion such that
`an absolute difference betWeen current and mo st recent path
`loss measurements has reached a threshold of difference.
`4. The method of claim 1, Wherein said set of at least one
`triggering criterion include any one of a plurality of criteria
`that each entail teaching a respective threshold.
`5. The method of claim 1, Wherein the set of at least one
`triggering criterion comprise a ?rst criterion, a second crite
`rion, and a third criterion.
`6. The method of claim 5, Wherein the ?rst criterion is such
`that a number of received closed loop poWer corrections has
`reached a threshold of corrections, and Wherein the second
`criterion is such that an amount of transmission time intervals
`folloWing an open loop poWer control modi?cation has
`reached a threshold of intervals since modi?cation.
`7. The method of claim 6, Wherein the third criterion is such
`that an amount of transmission time intervals folloWing a
`previous poWer control headroom report has reached a thresh
`old of intervals since reporting.
`8. The method of claim 6, Wherein the third criterion is such
`that an absolute difference betWeen current and most recent
`path-loss measurements has reached a threshold of differ
`ence.
`
`A preferred embodiment of the present invention Will noW
`be described. This is merely to illustrate one Way of imple
`menting the invention, Without limiting the scope or coverage
`of What is described elseWhere in this application.
`In this preferred embodiment, the reporting criteria are
`implemented in the terminal. HoWever, the protocol for sig
`nalling the parameters “n”, “m”, “k” and/ or “p” requires
`implementation at both the eNode-B and the terminal. This
`embodiment of the invention provides an attractive trade-off
`betWeen signalling overhead and performance.
`As seen in FIG. 3, the method 300 can begin With the base
`station adjusting 307 one or more of the thresholds “n”, “m”,
`“k” and/or “p” at the user equipment (U E) by signalling to the
`UE. At some subsequent point in time, the UE determines 315
`that a triggering criterion has been met because one of those
`thresholds have been reached (or some combination of those
`thresholds have been reached). This Will trigger the UE to
`provide 325 a poWer control headroom report on the uplink.
`When this report is received 335 at the base station, the base
`station Will then use that report to help provide 370 a closed
`loop poWer control correction command to the user equip
`ment.
`Referring noW to FIG. 4, a system 400 is shoWn according
`to an embodiment of the invention, including a netWork ele
`ment 492 and a user equipment 405. At the netWork element,
`a threshold adjustment module 468 instructs transceiver 454
`to send a threshold adjustment signal to the user equipment.
`At some subsequent point, a triggering module 413 at the user
`equipment determines that the threshold has been reached,
`and therefore instructs transceiver 411 to provide a poWer
`control headroom report to the netWork element, Which pro
`cesses the report in a report receiving module 463. The report
`receiving module 463 Will thereby help the netWork element
`to provide a closed loop poWer control correction command
`to the user equipment 405.
`Each of the embodiments described above can be imple
`mented using a general purpose or speci?c-use computer
`system, With standard operating system softWare conforming
`to the method described herein. The softWare is designed to
`drive the operation of the particular hardWare of the system,
`and Will be compatible With other system components and I/ O
`controllers. The computer system of this embodiment
`includes a CPU processor, comprising a single processing
`unit, multiple processing units capable of parallel operation,
`or the CPU can be distributed across one or more processing
`units in one or more locations, e.g., on a client and server. A
`memory may comprise any knoWn type of data storage and/or
`transmission media, including magnetic media, optical
`media, random access memory (RAM), read-only memory
`(ROM), a data cache, a data object, etc. Moreover, similar to
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`APPL-1001 / Page 9 of 11
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`US 8,457,676 B2
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`7
`9. The method of claim 1, wherein the set of at least one
`triggering criterion comprises a criterion being met based on
`reaching a threshold of the at least one threshold of n closed
`loop poWer corrections having been received by the user
`equipment over In transmission time intervals, Wherein n and
`m are integers and Wherein said at least one threshold adjust
`able via the signal comprises adjusting the threshold integers
`n and m.
`10. The method of claim 1, Wherein the set of at least one
`triggering criterion comprises a criterion being met based on
`reaching a threshold of the at least one threshold of m trans
`mission time intervals, folloWing an open loop poWer control
`modi?cation, Wherein m is an integer and Wherein said at
`least one threshold adjustable via the signal comprises adjust
`ing the threshold integer m.
`11. An apparatus comprising:
`means for determining that a set of at least one triggering
`criterion is met; and
`means for providing a poWer control headroom report on
`an uplink from user equipment, in response to the set
`having been met, Wherein said at least one triggering
`criterion include at least one threshold having been
`reached poWer correction, Wherein said at least one
`threshold is adjustable via a signal to the apparatus,
`Wherein the set of at least one triggering criterion com
`prises a criterion being met based on reaching a thresh
`old of the at least one threshold of k transmission time
`intervals folloWing a previous poWer control headroom
`report, Wherein k is an integer and Wherein said at least
`one threshold adjustable via the signal comprises adjust
`ing the threshold integer k.
`12. The apparatus of claim 11, Wherein said poWer control
`headroom report is for use in a poWer control correction
`command to the apparatus.
`13. The apparatus of claim 11, Wherein the set of at least
`one triggering criterion comprises a criterion such that an
`absolute difference betWeen current and most recent path
`loss measurements has reached a threshold of difference.
`14. The apparatus of claim 11, Wherein said set of at least
`one triggering criterion include any one of a plurality of
`criteria that each entail reaching a respective threshold.
`15. The apparatus of claim 11, Wherein the set of at least
`one triggering criteria comprise a ?rst criterion, a second
`criterion, and a third criterion.
`16. The apparatus of claim 15, Wherein the ?rst criterion is
`such that a number of received closed loop poWer corrections
`has reached a threshold of corrections, and Wherein the sec
`ond criterion is such that an amount of transmission time
`intervals folloWing an open loop poWer control modi?cation
`has reached a threshold of intervals since modi?cation.
`17. The apparatus of claim 16, Wherein the third criterion is
`such that an amount of transmission time intervals folloWing
`a previous poWer control headroom report has reached a
`threshold of intervals since reporting.
`18. The apparatus of claim 16, Wherein the third criterion is
`such that an absolute difference betWeen current and most
`recent path-loss measurements has reached a threshold of
`difference.
`19. An apparatus comprising:
`at least one processor; and
`at least one memory including software, Where the at least
`one memory and the softWare are con?gured, With the at
`least one processor, to cause the apparatus to at least:
`determine that a set of at least one triggering criterion is
`met; and
`provide a poWer control headroom report on an uplink from
`user equipment, in response to the set having been met,
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`Wherein said at least one triggering criterion include at
`least one threshold having been reached, Wherein said at
`least one threshold is adjustable via a signal to the appa
`ratus, Wherein the set of at least one triggering criterion
`comprises a criterion being met based on reaching a
`threshold of the at least one threshold of k transmission
`time intervals folloWing a previous poWer control head
`room report, Wherein k is an integer and Wherein said at
`least one threshold adjustable via the signal comprises
`adjusting the threshold integer k.
`20. The apparatus of claim 19, Wherein said poWer control
`headroom report is for use in a poWer control correction
`command to the apparatus.
`21. The apparatus of claim 19, Wherein the set of at least
`one triggering criteria comprises a triggering criterion such
`that an absolute difference betWeen current and most recent
`path-loss measurements has reached a threshold of differ
`ence.
`22. The apparatus of claim 19, Wherein said set of at least
`one triggering criterion include any one of a plurality of
`criteria that each entail reaching a respective threshold.
`23. The apparatus of claim 22, Wherein the plurality of
`criteria comprise a ?rst criterion, a second criterion, and a
`third criterion.
`24. The apparatus of claim 23, Wherein the ?rst criterion is
`such that a number of received closed loop poWer corrections
`has reached a threshold of corrections, and Wherein the sec
`ond criterion is such that an amount of transmission time
`intervals, folloWing an open loop poWer control modi?cation,
`has reached a threshold of intervals since modi?cation.
`25. The apparatus of claim 23, Wherein the second criterion
`is such that an amount of transmission time intervals folloW
`ing a previous poWer control headroom report has reached a
`threshold of intervals since reporting.
`26. The apparatus of claim 23, Wherein the third criterion is
`such that an absolute difference betWeen current and most
`recent path-loss measurements has reached a threshold of
`difference.
`27. A non-transitory computer readable medium including
`softWare that When executed by a processor, is adapted to
`carry out functions of:
`determining that a set of at least one triggering criterion is
`met; and
`providing a poWer control headroom report on an uplink
`from user equipment, in response to the set having been
`