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WO2014088792A1 - Variation du niveau d'émission de spectre dans un terminal de communication sans fil programmable - Google Patents

Variation du niveau d'émission de spectre dans un terminal de communication sans fil programmable Download PDF

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Publication number
WO2014088792A1
WO2014088792A1 PCT/US2013/070654 US2013070654W WO2014088792A1 WO 2014088792 A1 WO2014088792 A1 WO 2014088792A1 US 2013070654 W US2013070654 W US 2013070654W WO 2014088792 A1 WO2014088792 A1 WO 2014088792A1
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WO
WIPO (PCT)
Prior art keywords
wireless communication
band
power
signaling
entity
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Ceased
Application number
PCT/US2013/070654
Other languages
English (en)
Inventor
Ryan J. GOEDKEN
Armin W. Klomsdorf
Thomas D. Nagode
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Motorola Mobility LLC
Original Assignee
Motorola Mobility LLC
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Priority claimed from US13/693,469 external-priority patent/US9622190B2/en
Application filed by Motorola Mobility LLC filed Critical Motorola Mobility LLC
Publication of WO2014088792A1 publication Critical patent/WO2014088792A1/fr
Anticipated expiration legal-status Critical
Ceased legal-status Critical Current

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Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W52/00—Power management, e.g. Transmission Power Control [TPC] or power classes
    • H04W52/04—Transmission power control [TPC]
    • H04W52/06—TPC algorithms
    • H04W52/14—Separate analysis of uplink or downlink
    • H04W52/146—Uplink power control
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W52/00—Power management, e.g. Transmission Power Control [TPC] or power classes
    • H04W52/04—Transmission power control [TPC]
    • H04W52/52—Transmission power control [TPC] using AGC [Automatic Gain Control] circuits or amplifiers
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L5/00—Arrangements affording multiple use of the transmission path
    • H04L5/003—Arrangements for allocating sub-channels of the transmission path
    • H04L5/0058—Allocation criteria
    • H04L5/0066—Requirements on out-of-channel emissions
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L5/00—Arrangements affording multiple use of the transmission path
    • H04L5/003—Arrangements for allocating sub-channels of the transmission path
    • H04L5/0058—Allocation criteria
    • H04L5/0073—Allocation arrangements that take into account other cell interferences
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W52/00—Power management, e.g. Transmission Power Control [TPC] or power classes
    • H04W52/04—Transmission power control [TPC]
    • H04W52/18—TPC being performed according to specific parameters
    • H04W52/24—TPC being performed according to specific parameters using SIR [Signal to Interference Ratio] or other wireless path parameters
    • H04W52/243—TPC being performed according to specific parameters using SIR [Signal to Interference Ratio] or other wireless path parameters taking into account interferences
    • H04W52/244—Interferences in heterogeneous networks, e.g. among macro and femto or pico cells or other sector / system interference [OSI]
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W52/00—Power management, e.g. Transmission Power Control [TPC] or power classes
    • H04W52/04—Transmission power control [TPC]
    • H04W52/30—Transmission power control [TPC] using constraints in the total amount of available transmission power
    • H04W52/36—Transmission power control [TPC] using constraints in the total amount of available transmission power with a discrete range or set of values, e.g. step size, ramping or offsets
    • H04W52/367—Power values between minimum and maximum limits, e.g. dynamic range
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W72/00—Local resource management
    • H04W72/12—Wireless traffic scheduling
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W72/00—Local resource management
    • H04W72/20—Control channels or signalling for resource management
    • H04W72/23—Control channels or signalling for resource management in the downlink direction of a wireless link, i.e. towards a terminal

Definitions

  • a frequency band adjacent to such a UE may be known from national or international regulations or from general deployment criteria, such as "licensed” or “unlicensed” designations to be subject to specific maximum levels of interference from the band in which the UE is operating.
  • this information is stored in the UE or made available by signaling from the network, the UE may optimize its radiated power level subject to the known adjacent band interference limits.
  • the radio resource allocated to a schedulable wireless communication entity is based on an interference impact of the schedulable wireless communication entity operating on the radio resource allocated.
  • the interference impact may be based on any one or more of the following factors: a transmission waveform type of the schedulable wireless communication entity; a maximum allowed and current power level of the schedulable wireless communication entity; bandwidth assignable to the schedulable wireless communication entity; location of the assignable bandwidth in a carrier band; radio frequency distance (path loss) relative to another wireless communications entity; variation in the maximum transmit power of the schedulable wireless communication entity for the assigned bandwidth; separation of assigned band relative to the other wireless communication entity; reception bandwidth of the victim entity, minimum SNR required for operation of the victim entity; the identified band upon which a schedulable wireless entity is supposed to transmit; the nearness of dedicated bands upon which the schedulable wireless entity is not supposed to transmit or interfere with, e.g., bands that have sensitive bands with reduced emissions requirements such as Band 13 which is adjacent to
  • the WPD accounts for waveform attributes such as modulation and number of frequency or code channels and can be determined empirically through power amplifier measurements or indicated by a waveform metric such as the Cubic Metric (CM).
  • CM Cubic Metric
  • the additional power de-rating from OBPD generally means worse cell edge coverage for wireless terminals unless mitigated. For example, a transmission with 4.5 MHz occupied bandwidth on a 5 MHz E-UTRA carrier with a fixed 5 MHz carrier separation will have a larger measured ACLR (e.g., approximately -30 dBc instead of -33 dBc) with regard to the adjacent 5 MHz carrier than a transmission with only 3.84 MHz occupied bandwidth.
  • the UE's current, or instantaneous, or local maximum power level is limited to the operational maximum power level given by PMAX-f(OBPD,WPD) where f(.) can, for example, be the simple summation of OBPD and WPD such that the operational maximum power level is PMAX-(OBPD+WPD).
  • f(.) can, for example, be the simple summation of OBPD and WPD such that the operational maximum power level is PMAX-(OBPD+WPD).
  • the difference between PMAX and the UE's current power level after power control or after assignment of an arbitrary power level less than PMAX is called the UE's power margin or power headroom. Scheduling can be used to reduce or avoid OBPD.
  • the scheduler finds a bandwidth size that reduces OBPD enough such that operational maximum power (PMAX-OBPD-WPD) does not limit current power of the schedulable wireless communication entity.
  • the user terminal is scheduled with low path loss for all but the resource blocks at the band edge to mitigate the OBPD that would otherwise be required.
  • the user terminal with high path loss would be scheduled for those band edge resource blocks because its OBPD would be less since the OBW is relatively small.
  • Signaling overhead may be reduced by using pre-determined hopping patterns, or pre-defined logical physical permutations.
  • a UE will determine the OBPD corresponding to its scheduled or allocated bandwidth size and location of the allocated bandwidth in the carrier band. The UE therefore computes an operational maximum power for every scheduled transmission to determine if the current power level will be limited.
  • a BS may execute such scheduling decisions not simply from considerations of interference offered by a UE to frequency-adjacent BS's, but may also simultaneously optimize the performance of multiple UE's whose allocated resources are derived from a common set of carrier frequency resources (possibly extending over more than one carrier frequency). That is, the BS may optimize its scheduling allocations from consideration of the mutual interference offered between a multiplicity of UE's.
  • band 26 which is a superset of band 5
  • band 26 is another band being contemplated to have strict adjacent band emissions standards similar to those of band 13.
  • band 26 may have a requirement as high as 12 dB additional maximum power reduction (A-MPR), which would be equivalent to that set forth for band 13.
  • A-MPR additional maximum power reduction
  • usage of the look-up tables 609 would provide similar current drain adjustments to that expected with band 13.
  • the communication entity is based on a maximum power available to the schedulable wireless communication entity for the radio resource allocated along or in combination with other factors, for example, the interference impact.
  • the scheduler knows the maximum transmit power of the corresponding schedulable wireless communication device. The scheduler may thus use this information to manage the scheduling of schedulable wireless communication entities, for example, to reduce interference.
  • the scheduler determines a bandwidth size of the radio
  • the scheduler allocates a radio resource to the schedulable wireless communications entity nearer an edge of a carrier band when a radio frequency distance between the schedulable wireless communication entity and the other wireless communications entity is larger, and the scheduler allocates the radio resource to the schedulable wireless communications entity farther from the edge of the carrier band when the radio frequency distance between the schedulable wireless communication entity and the other wireless communications entity is smaller.
  • FIG. 5 illustrates, for successive transmission time intervals or TTI's (frames) 508, resource allocations to UE1 502 that are centered in the allocable band about DC and allocations for UE2 504 and UE3 506 located at each band edge.
  • FIG. 5 shows a carrier band of 5 MHz with 4.5 MHz of allocable bandwidth in units of 375 kHz resource blocks (RB's) such that 12 RB's span the entire 4.5 MHz.
  • Adjacent carriers are on either side of the 5 MHz carrier and are typically separated by a guard band. Out of band emissions decrease more rapidly when band edge occupancy is reduced or avoided.
  • OBPD also decreases more rapidly 510. If, for example, two or more RB's at the band edge are not allocated then the OBPD may be less than 0.
  • Out of band emissions (and OBPD 516) for allocations that include band edge RB's as shown for UE4 512 and UE5 514 decrease more slowly as the allocation is reduced compared to Band centered allocations. In the particular example shown, not until the occupancy of a resource allocation with band edge RB's 512 UE4 drops below 1/3 of the total allocable band does the OBPD drop below zero 518.
  • the BS may enhance its ability to optimally adjust the maximum permitted power level of UE's under the control of the BS by occasionally measuring the BS receiver noise power contribution arising from reduced transmitter waveform quality among UE's.
  • FIG. 7a illustrates this method in more detail in the context of OFD transmissions, or more generally transmissions comprising multiple sub-carriers. Specifically, a UE is shown transmitting on a set of active frequency sub-carriers 701 received at the BS receiver with a specific energy per sub-carrier Esl 700 and with an associated signal-noise ratio Esl/Nt with respect to the BS receiver thermal noise power density Nt 702.
  • this band allows up to 12 dB of A-MPR to meet the tight emissions requirements.
  • Adding the look-up tables (609) described with reference to FIG. 6 above allows a controller (603) or other device to switch between the two tables based on NS 07 signaling as previously described.
  • the BS may broadcast an indication of a) the BS receiver thermal noise density Nt, b) the received noise component Ne due to UE transmitter impairments, or c) a combination, sum, or some function of those measures.
  • the UE may then optimize its maximum transmitter power level to optimize the sub-carrier signal-noise ratio or adjust the operating point as discussed above. For example, if the UE had available, from downlink power measurements, for example, an estimate of the path loss between the BS and UE, the UE may select the maximum radiated power level such that the received energy per sub-carrier and associated receiver noise power density Ne, due to transmitter impairments, is optimized.
  • the BS may elect to schedule specific time-frequency instances, or measurement opportunities, where a known set of sub-carriers 706 or other time- frequency resources are known to be absent. This permits the BS receiver to measure the desired noise power statistic (say, Nt+Ne) as shown in FIG. 7b.
  • the desired noise power statistic say, Nt+Ne
  • the BS may also transmit to a specific UE (unicast), or broadcast over a specific cell or cells or over the entire network a specified measure of the ratio, measured at the UE PA output, between the energy per active sub-carrier Es, and the equivalent noise power density in inactive sub-carriers.
  • a UE receiving such an indication, via a common or dedicated control channel, would then a) adjust their maximum power level or operating point such that the ratio Es/Ne is aligned with the specified broadcast or unicast value.
  • the BS may also transmit an upper or lower bound on this ratio.
  • the transmission on the control channel of such a measure would require quantization of the specified value or bound to an integer word of a number N of bits.
  • the TPD applied to the power amplifier is a function of OPD and
  • relaxed emissions may be signaled by the base station to a specific UE or it may be transmitted on a broadcast control signal.
  • the signaling may directly set the appropriate emissions level, or it may provide enough information for the UE to intelligently determine an appropriate emission level.
  • the UE may respond by adjusting the PA supply voltage and/or adjusting the PA load line, both resulting in improved device efficiency.
  • the appropriate emission level is the level at which all regulatory and system requirements, at the time of transmission, are met.
  • the appropriate emission level will change from location to location, with regard to regulatory requirements from time to time and with regard to the distribution of other system users.
  • Pertinent information about other users includes modulation type, modulation bandwidth, frequency offset, and transmit duration. Any of these properties can change quickly and often, for example, every 0.5 ms.
  • each UE has knowledge of every other UE's
  • an algorithm uses the provided information and transmitter characteristics to adjust the transmitter so that interference is minimized.
  • the algorithm generally uses implicit rules but may be directed by the BS to modify some of these rules and even add additional rules.
  • This signaling permits a UE to autonomously relax waveform quality, for example, based on emissions requirements.
  • This signaling may also allow the UE to adjust waveform quality during network access, for example, during Random Access Channel (RACH) access.
  • RACH Random Access Channel
  • FIG. 8 is a PA circuit 800 configured in accordance with one or more embodiments of the invention.
  • the PA circuit 800 is configured to adjust a voltage level 805 of a PA 808 based upon NS 07 signaling. Rather than using look-up tables (609) to set DCDC values based upon NS 07 signaling, the PA circuit 800 of FIG. 8 uses an envelope- tracking schema to adjust the voltage level 805.
  • the PA circuit 800 includes a baseband processor 881 that communicates with a transceiver 882 via transmit (Tx) and receive (Rx) lines to transmit and receive wireless data signals. During transmission, the transceiver 882 has an output 883 that is coupled to the PA 808.
  • the PA 808 delivers amplified signals to a frontend network 886 that is operable with an antenna 887.
  • An envelope generator 888 and power supply control circuit 889 work in tandem to track the data signals 885 and provide a variable supply voltage to the PA 808.
  • the envelope generator 888 can include an envelope detector operable to determine an envelope signal 880 from the data signals 885 as is known in the art.
  • the power supply control circuit 889 which in one embodiment is a tracking power supply, is operable to control a voltage level 805 of the PA 808 with the envelope signal 880.
  • the transceiver 882 can include input signal conditioners, such as nonlinear phase mappers, phase adjusters, nonlinear gain mappers, and gain adjusters, which can function to essentially pre-distort or otherwise condition an input signal to provide a conditioned data signal to the PA 808.
  • input signal conditioners can be included to counteract any phase and gain distortions introduced within the PA 808 from variations in the supply voltage coming from the power supply control circuit 889.
  • the inclusion of input signal conditioners working in tandem with the envelope generator 888 and the power supply control circuit 889, work to minimizes phase and gain distortions in the amplified output signal. Moreover, it can provide for effectively linear, high efficiency power amplification in broadband applications.
  • Such input signal conditioners are described in commonly assigned US Published Patent Application No. 2002/0094795, entitled "High Efficiency Wideband Linear Wireless Power Amplifier,” which is incorporated herein by reference for all purposes.
  • the envelope generator 888 may adjust the envelope signal in accordance with shaping tables stored in a memory 842 that is operable with the envelope generator 888.
  • the shaping tables may adjust the envelope signal to optimize linearity of the amplified signal from the PA 808.
  • the linearity of the PA 808 can be improved by using the envelope generator 888 to increase the power value peak above a power supply maximum level.
  • Shaping tabes stored in the memory 842 can also be used to linearize the PA response by choosing an "iso-gain" profile, rather than letting gain of the PA 808 vary as amplitude modulation drives the PA 808 into and out of compression.
  • NS 07 is not signaled
  • are more aggressive shaping table stored in the memory 842 can be used. The more aggressive shaping tables may compromise linearity of the amplified signal to achieve better emissions performance and/or reduced current drain.
  • each UE only has knowledge of its own transmit parameters. Algorithms similar to the one described above are performed at the BS and relevant results are relayed to each UE.
  • the BS may directly indicate that waveform quality may be reduced and by what amount.
  • the UE must determine the appropriate adjustments based on unique transmitter characteristics to match levels determined by the BS. Use of emission reducing filters and parameters of those filters may be defined by the BS and may change some of the implicit rules for the transmitter adjustments.

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  • Engineering & Computer Science (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Signal Processing (AREA)
  • Mobile Radio Communication Systems (AREA)

Abstract

La présente invention se rapporte à une entité de communication sans fil qui est programmable dans un réseau de communication sans fil, ladite entité comprenant un dispositif de commande (603) couplé en communication à un amplificateur de puissance (608), le dispositif de commande (603) faisant varier un niveau d'émission de spectre de l'entité de communication sans fil sur la base d'informations d'attribution de ressources radio reçues par le récepteur radio telles que savoir si la signalisation NS est active. Des exemples de la signalisation NS consistent à envoyer un drapeau de signalisation NS_07 pour permettre une signalisation de bande 13 ou l'un d'un drapeau de signalisation NS_12 à NS_15 pour la bande 26.
PCT/US2013/070654 2012-12-04 2013-11-19 Variation du niveau d'émission de spectre dans un terminal de communication sans fil programmable Ceased WO2014088792A1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US13/693,469 US9622190B2 (en) 2006-07-25 2012-12-04 Spectrum emission level variation in schedulable wireless communication terminal
US13/693,469 2012-12-04

Publications (1)

Publication Number Publication Date
WO2014088792A1 true WO2014088792A1 (fr) 2014-06-12

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Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2018069564A1 (fr) * 2016-10-10 2018-04-19 Nokia Technologies Oy Application d'exigences de performance radiofréquence minimale à des transmissions de liaison montante
US10412692B2 (en) 2014-08-08 2019-09-10 Telefonaktiebolaget Lm Ericsson (Publ) D2D power control
CN115769640A (zh) * 2020-07-02 2023-03-07 哲库科技有限公司 发射器电源管理机制和相关操作方法
US20230319736A1 (en) * 2022-03-11 2023-10-05 Apple Inc. Method for multiple power class support
US20240080233A1 (en) * 2022-09-01 2024-03-07 Qualcomm Incorporated Techniques for waveform compression

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US20020094795A1 (en) 2001-01-18 2002-07-18 Motorola, Inc. High efficiency wideband linear wireless power amplifier
US20080025254A1 (en) * 2006-07-25 2008-01-31 Motorola Inc Spectrum emission level variation in schedulable wireless communication terminal
WO2012150887A1 (fr) * 2011-05-03 2012-11-08 Telefonaktiebolaget L M Ericsson (Publ) Procédés et nœuds de réseau dans un système de télécommunication

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US20020094795A1 (en) 2001-01-18 2002-07-18 Motorola, Inc. High efficiency wideband linear wireless power amplifier
US20080025254A1 (en) * 2006-07-25 2008-01-31 Motorola Inc Spectrum emission level variation in schedulable wireless communication terminal
WO2012150887A1 (fr) * 2011-05-03 2012-11-08 Telefonaktiebolaget L M Ericsson (Publ) Procédés et nœuds de réseau dans un système de télécommunication

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Cited By (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US10412692B2 (en) 2014-08-08 2019-09-10 Telefonaktiebolaget Lm Ericsson (Publ) D2D power control
EP3178266B1 (fr) * 2014-08-08 2023-05-31 Telefonaktiebolaget LM Ericsson (publ) Commande de puissance dispositif à dispositif (d2d)
WO2018069564A1 (fr) * 2016-10-10 2018-04-19 Nokia Technologies Oy Application d'exigences de performance radiofréquence minimale à des transmissions de liaison montante
CN109804675A (zh) * 2016-10-10 2019-05-24 诺基亚技术有限公司 将最低无线电频率性能要求应用于上行链路传输
US11178615B2 (en) 2016-10-10 2021-11-16 Nokia Technologies Oy Applying minimum radio frequency performance requirements to uplink transmissions
CN109804675B (zh) * 2016-10-10 2022-03-29 诺基亚技术有限公司 将最低无线电频率性能要求应用于上行链路传输
CN115769640A (zh) * 2020-07-02 2023-03-07 哲库科技有限公司 发射器电源管理机制和相关操作方法
US20230319736A1 (en) * 2022-03-11 2023-10-05 Apple Inc. Method for multiple power class support
US12495370B2 (en) * 2022-03-11 2025-12-09 Apple Inc. Method for multiple power class support
US20240080233A1 (en) * 2022-09-01 2024-03-07 Qualcomm Incorporated Techniques for waveform compression
US12401557B2 (en) * 2022-09-01 2025-08-26 Qualcomm Incorporated Techniques for waveform compression

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