Classifications

• • 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
  • H04L5/0044—Arrangements for allocating sub-channels of the transmission path allocation of payload
• • H—ELECTRICITY
  • H04—ELECTRIC COMMUNICATION TECHNIQUE
  • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
  • H04L1/00—Arrangements for detecting or preventing errors in the information received
  • H04L1/12—Arrangements for detecting or preventing errors in the information received by using return channel
  • H04L1/16—Arrangements for detecting or preventing errors in the information received by using return channel in which the return channel carries supervisory signals, e.g. repetition request signals
  • H04L1/18—Automatic repetition systems, e.g. Van Duuren systems
  • H04L1/1829—Arrangements specially adapted for the receiver end
  • H04L1/1854—Scheduling and prioritising arrangements
• • H—ELECTRICITY
  • H04—ELECTRIC COMMUNICATION TECHNIQUE
  • H04W—WIRELESS COMMUNICATION NETWORKS
  • H04W56/00—Synchronisation arrangements
  • H04W56/0005—Synchronisation arrangements synchronizing of arrival of multiple uplinks
• • H—ELECTRICITY
  • H04—ELECTRIC COMMUNICATION TECHNIQUE
  • H04W—WIRELESS COMMUNICATION NETWORKS
  • H04W72/00—Local resource management
  • H04W72/20—Control channels or signalling for resource management
  • H04W72/21—Control channels or signalling for resource management in the uplink direction of a wireless link, i.e. towards the network
• • H—ELECTRICITY
  • H04—ELECTRIC COMMUNICATION TECHNIQUE
  • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
  • H04L1/00—Arrangements for detecting or preventing errors in the information received
  • H04L1/12—Arrangements for detecting or preventing errors in the information received by using return channel
  • H04L1/16—Arrangements for detecting or preventing errors in the information received by using return channel in which the return channel carries supervisory signals, e.g. repetition request signals
  • H04L1/1607—Details of the supervisory signal
  • H04L1/1671—Details of the supervisory signal the supervisory signal being transmitted together with control information
• • 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

• the invention relates to channel configuration and timing for Enhanced Uplink DCH (EU-DCH) , in particular to a method for transmitting information between a UE (mobile station) and a Node B (base station or base station system) and a radio set (mobile station or base station) .
• EU-DCH Enhanced Uplink DCH
• EU-DCH will be used together with HSDPA and UE complexity as well as required processing power needs to be kept as low as possible.
• the EU-DCH should be able to accommodate different types of data traffic (long versus short packet calls) and different degrees of mobility (i.e. varying channel coherence times) .
• the EU-DCH data channel should be implemented in a backward-compatible evolutionary way and should reuse existing UMTS features wherever possible.
• Mc2 proposes to use uplink and downlink control channels with 10 ms frame size, i.e. scheduling is basically done by sending a map of resource grants for 5 consecutive 3- slot TTIs of data within one control message.
• a 3-slot (2 ms) format is used for the downlink ACK/NACK control channel.
• the timing of EU-DCH (and their relative timing to HSDPA channels) is not addressed in this paper.
• Nokia [Nok2] discusses a method, which allows to operate EU- DCH with very low physical layer signalling.
• the UE issues a rate request (RR) message and the corresponding answer of the Node B is a rate grant (RG) message.
• RR rate request
• RG rate grant
• Time alignment of channels In order to enable efficient interference management at Node B, the timing of all uplink channels which create bursty interference should be aligned. To allow this interference management and additionally to support power management at UE the uplink control channel of HSDPA (HS-DPCCH) and the data channel of the enhanced uplink (EU-DCH) shall be time aligned. These are the most important channels with bursty traffic, i.e., channels that cause bursty interference. Node B can manage the expected interference in the forthcoming TTIs and slots since it has knowledge on the time when it expects CQI, ACK/NACK messages, and data on EU-DCH.
• HSDPA HSDPA
• EU-DCH enhanced uplink
• Node B can control the received interference by appropriate scheduling and the time alignment of EU-DCH and HS-DPCCH ensures maximum efficiency and minimum complexity of this process.
• Fig. 1 gives an overview over the discussed data and control channels for EU-DCH and HSDPA.
• the network has the capability of shifting the EU-DCH and HS- DPCCH of each UE in a way that the reception of this data at Node B occur on a 3-slot grid for all UEs.
• this could be achieved by the timing parameters T n and/or ⁇ c ⁇ as defined in [25.211], which adjust the start of the DCH and HS-DPCCH with respect to the frame border.
• T e timing adjustment parameter
• T e could either adjust the timing of both, HS-DPCCH and EU-DCH or only of EU-DCH.
• the second solution would trade the alignment of HS- DPCCH and EU-DCH per UE with the alignment of all EU-DCHs to a 3-slot grid. Note, that a general drawback of this additional timing offset T e is that it increases total round trip delay. Therefore another ' solution would be not to use active per-TTI interference management but semi-static interference averaging by an assignment strategy for T n that jointly optimises power and interference for DCH and EU-DCH.
• control information like request for uplink resources, UE buffer status, transport format of the data, or information on available transmission power resources at UE must be sent from UE to the network.
• This uplink control information for EU-DCH (denoted as EU- DPCCH in this text) can either be a separate DPCCH or be multiplexed into HS-DPCCH by reducing the spreading factor and using blind format detection at Node B. Note that the separate DPCCH results in higher peak-to-average-power ratio due to multi-code transmission, while multiplexing with HS- DPCCH might reduce CQI decoding performance at Node B.
• the uplink control information for EU-DCH (denoted as EU-DPCCH in this text) shall be time aligned with the HS-DPCCH field that on average required the smallest transmit power, e.g. the CQI field of HS-DPCCH.
• the CQI field of HS-DPCCH For UE power management it is favourable not to send the EU-DPCCH in parallel to the ACK/NACK (A/N) of HS-DPCCH, since the latter will use higher transmission power than the CQI message.
• time alignment with the CQI slots allows a favourable split between processing time available at UE and at Node B, as will be detailed in the following. As a result, a 2-slot format for EU-DPCCH should be adopted.
• EU-DCH available at the UE TUEP, EU - DCH / i.e., the time interval from end of reception of the downlink control channel, denoted as EU-SCCH in the sequel, until beginning of EU-DCH transmission, is required for EU-SCCH decoding and EU-DCH encoding.
• SCCH timing shall be reused for EU-SCCH, this time is a free parameter and can be adjusted such that it is equal to the actually required processing time in the UE tu ⁇ p,re :
• Node B T NP ,Eu-DCH i.e. time between reception of EU-DCH and start of corresponding EU-SCCH transmission
• T NP EU-DCH ⁇ TRT-V EU-SCH + T UEP,EU-DCH +t EU-DCH + 2 " * prop ) r ( 1 0 )
• T RT is the total round-trip delay (a system design variable)
• t E u-sc H is the duration of the EU-SCCH sub-frame
• tEu-DCH is the duration of the EU-DCH TTI
• t pr ⁇ p is the propagation time between Node B and UE. This time is available for EU-DCH decoding, scheduling decision and EU-SCCH.
• t EU -scH ⁇ t EU -DCH and T RT p ⁇ t E u-DCH .
• the sub-frame length of the downlink control channel corresponds to the TTI length and the total round-trip delay is a multiple thereof, i.e. p is an integer.
• EU-DPCCH For power and interference management reason EU-DPCCH is time aligned with a CQI field of HS-DPCCH. Therefore the time interval between the end of reception of EU-SCCH and the start of EU-DPCCH transmission TUEP,EU-DPCCH can be set to:
• E U- DP CC H AEP, E U- DC H + 2 ( 3 • t s!ot + D - t EU _ DCH , ( 1 1 )
• t ⁇ iot s the duration of one slot .
• EU - DCH need to be used for UEs using the first, the second and the third slot of a 3-slot sub-frame (denoted as variable timing in the following) . Note, that the different values of T UEP . EU - DCH need not to be signalled to UE explicitly but can be determined using the slot number of the start of the EU-SCCH sub-frame. For example the following equation can be used:
• TUEP ,EU- D C H Tu EP , E U- D C H ,0 + TTI ⁇ ⁇ s l ot ⁇ dN m ))-t slot , ( 13 )
• TUEP,EU-DCH,O is the basic UE processing time
• N TT ⁇ is the number of slots per TTI used for EU-DCH transmission.
• the processing time becomes
• TNP,EU-D C H AP,EU-D C H, O + ( ⁇ s t ⁇ l)mod N TTI )-t sht , ( 14 ) where n slot denotes the slot number of the begin of the EU-SCCH sub-frame .
• Shorter control information sub-frames will increase the average available processing time for the same round-trip delay or equivalently allows shorter round-trip delay for identical processing time available. However, the worst-case processing time at the UE and Node B remains unchanged.
• shorter con- trol messages allow to save downlink code consumption.
• the reduced downlink code consumption in turn alleviates the need for fast switching between connection states (e.g. between
• the basic UE processing time TUEP,EU-DCH,O can be easily derived based on the considerations and equations in the previous sections.
• the use of a separate downlink control channel can result in low overall decoding processes required in the UE.
• a multi-TTI transmission which comprises L TTIs, where L is a parameter that the Node B assigns depending on various criteria, like data backlog, HARQ process states, QoS parameters, channel coherence time and interference management considerations.
• a multi-TTI transmission consists of L individual packets.
• the major advantage of the multi-TTI transmission is that only one EU- SCCH control information is required for L packets and scarce downlink code resources are saved. Furthermore the UE needs not to monitor EU-SCCH during the duration of the multi-TTI transmission.
• Multi-TTI transmission allow a simple adaptation to the traffic type and to channel coherence time while maintaining the simplicity of a N-channel Stop-And-Wait HARQ protocol.
• the parameter L must be signalled in the resource grant message from the Node B.
• each packet can be sent with its individual format and no resources on the uplink control channel EU- DPCCH can be saved.
• a multi-TTI uplink control format can be introduced, which is applied if all packets use the same transport format. This is especially useful for UEs that have slow or small variations in the channel conditions.
• multi-TTI uplink control format various alternatives are possible:
• Fig. 2 the channel configuration (time alignment of EU-DCH and HS-DPCCH) and timing is exemplified for one particular parameter setting, that provides reasonable processing time at both, Node B and UE, and at the same time results in equal round-trip delay T RT for HSDPA and EU-DCH transmission.
• a separate downlink control channel (EU-SCCH) is used.
• EU-SCCH downlink control channel
• the relative timing of EU-SCCH is simply determined by TU EP ,Eu-DCH r which in turn is chosen simply as the required processing time at the UE .
• the EU-DPCCH is sent in parallel to the first two slots of EU-DCH (and of course time aligned with a CQI field of HS-DPCCH) .
• Such a timing can be useful if the transport format of EU-DCH is (at least partly) determined by the UE . Note, that also for
• Fig. 3 shows the same implementation as depicted in Fig. 2. The only difference is that t E u-scH ⁇ t E u-DCH . i.e., a 1-slot EU-SCCH format is used and three different UEs can receive EU-SCCH within 3 slots.
• One additional slot processing time is now available at both, Node B and UE, if the "middle" EU- SCCH slot is used (orange coloured slot of EU-SCCH) .
• the grey slots of EU-SCCH and the dotted lines correspond to the timing of Fig. 2. For the first slot, only the UE would benefit from additional processing time (2 slots) , while for the last slot only Node B would have two additional slots of processing time. As already stated above, the worst-case processing time remains unchanged. However, more UEs can share one EU-SCCH channel in time multiplex.
• Abbreviations :
• HSDPA uplink control channel EU-DCH Enhanced Uplink Dedicated Channel (enhanced uplink data channel) EU-SCCH Enhanced Uplink Shared Control Channel (EU-DCH downlink control channel)
• EU-DPCCH Enhanced Uplink Dedicated Physical Control Channel

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

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• 2003
  • 2003-11-25 AU AU2003302343A patent/AU2003302343A1/en not_active Abandoned
  • 2003-11-25 WO PCT/EP2003/013260 patent/WO2004049648A2/en not_active Application Discontinuation
  • 2003-11-25 EP EP03811773A patent/EP1566027A2/de not_active Withdrawn

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