GB2447251A - Method of scheduling resources in a communication system - Google Patents

Method of scheduling resources in a communication system Download PDF

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Publication number
GB2447251A
GB2447251A GB0620921A GB0620921A GB2447251A GB 2447251 A GB2447251 A GB 2447251A GB 0620921 A GB0620921 A GB 0620921A GB 0620921 A GB0620921 A GB 0620921A GB 2447251 A GB2447251 A GB 2447251A
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United Kingdom
Prior art keywords
controlled
channel
higher level
base station
code space
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.)
Withdrawn
Application number
GB0620921A
Other versions
GB0620921D0 (en
Inventor
Volker Breuer
Thomas Malcolm Chapman
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.)
Siemens AG
Original Assignee
Siemens AG
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
Application filed by Siemens AG filed Critical Siemens AG
Priority to GB0620921A priority Critical patent/GB2447251A/en
Publication of GB0620921D0 publication Critical patent/GB0620921D0/en
Priority to PCT/GB2007/050637 priority patent/WO2008050152A1/en
Publication of GB2447251A publication Critical patent/GB2447251A/en
Withdrawn legal-status Critical Current

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Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04B—TRANSMISSION
    • H04B1/00—Details of transmission systems, not covered by a single one of groups H04B3/00 - H04B13/00; Details of transmission systems not characterised by the medium used for transmission
    • H04B1/69—Spread spectrum techniques
    • H04B1/707—Spread spectrum techniques using direct sequence modulation
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04J—MULTIPLEX COMMUNICATION
    • H04J13/00—Code division multiplex systems
    • H04J13/16—Code allocation
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04J—MULTIPLEX COMMUNICATION
    • H04J11/00—Orthogonal multiplex systems, e.g. using WALSH codes
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04J—MULTIPLEX COMMUNICATION
    • H04J13/00—Code division multiplex systems
    • H04Q7/38—
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W72/00—Local resource management
    • H04W72/50—Allocation or scheduling criteria for wireless resources
    • H04W72/56—Allocation or scheduling criteria for wireless resources based on priority criteria
    • H04W72/563—Allocation or scheduling criteria for wireless resources based on priority criteria of the wireless resources
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04J—MULTIPLEX COMMUNICATION
    • H04J13/00—Code division multiplex systems
    • H04J13/0007—Code type
    • H04J13/004—Orthogonal
    • H04J13/0044—OVSF [orthogonal variable spreading factor]
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W28/00—Network traffic management; Network resource management
    • H04W28/16—Central resource management; Negotiation of resources or communication parameters, e.g. negotiating bandwidth or QoS [Quality of Service]
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W72/00—Local resource management
    • H04W72/04—Wireless resource allocation
    • H04W72/044—Wireless resource allocation based on the type of the allocated resource
    • H04W72/0466—Wireless resource allocation based on the type of the allocated resource the resource being a scrambling code
    • 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

Landscapes

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

Abstract

A method of scheduling resources in a communication system comprising a terminal, a base station and a higher level entity than the base station, where the method comprises allocating code space for users of a channel controlled by the base station and allocating the same code space for users of a channel controlled by the higher level entity. It is determined whether there is ongoing, or imminent higher level controlled communication in each part of the code space and for any part of the code space where there is no higher level controlled communication, that part of the code space is scheduled for base station controlled communication. The specific embodiment relates to a UTRAN FDD system, where orthogonal variable spreading factor (OVSF) codes (channelisation codes) need to be reserved for users in a CELL_DCH (dedicated channel) state (who use a base station controlled HS-DSCH channel) and for users in a CELL_FACH (non dedicated channel) state, (who use a use a RNC (higher level entity) controlled S-CCPCH channel). The code allocation and scheduling method of the invention addresses the problem that the code reserved for the S-CCPCH is used infrequently and would be useful for the code limited HS-DSCH. The method may also be used in UTRA TDD, TD-SCDMA and CDMA2000 systems.

Description

A METHOD OF SCHEDULING RESOURCES INI A COMMUNICATION SYSTEM
This invention relates to a method of scheduling resources in a communication system, in particular for cellular communication systems.
This invention is particularly applicable to code division multiple access (CDMA) based cellular radio systems, such as universal terrestrial radio access network (UTRAN) freque ncy division duplex system (FDD). In Release 6 UTRAN FDD systems, an orthogonal variable spreading factor (OVSF) code space is provided, part of which needs to be reserved for communication with users that are in CELL_FACH state and is controlled from a radio network controller (RNC) using a secondary common control physical channel (S-CCPCH). The other part of the OVSF code space may be reserved for communicating with users in CELL_DCH state, controlled from the Node B using a high speed downlink shared channel (HS-DSCH).
HS-DSCH tends to be code limited, rather than power limited, whereas S-CCPCH is used relatively infrequently and hence the valuable OVSF code space allocated to S-CCPCH is wasted most of the time.
A proposal has been made in the 3'" generation partnership project (3GPP), for the HS-DSCH to be used for carrying a forward access channel (FACH) for users in CELL_FACH state rather than using the S-CCPCH. However, this approach has several disadvantages. Channel quality indication (CQI) feedback and no ACKINACK feedback is not possible. Thus, hybrid automatic repeat request (HARQ) and frequency dependent scheduling, two very important features of high speed downlink packet access (HSDPA), are not possible. Also, as the HS-DSCH has a transmit time interval (TTI) of 2msec and no power control is available, such a short TTI is disadvantageous as it offers zero time diversity. Furthermore, there is no power control information available for the high speed shared control channel (HS-SCCH), so the signalling overhead will be quite large In accordance with the present invention, a method of scheduling resources in a communication system comprising a terminal, a base station and a higher level entity than the base station comprises allocating code space for users of a channel controlled by the base station and allocating the same code space for users of a channel controlled by the higher level entity; determining whether there is ongoing or imminent higher level controlled communication in each part of the code space and for any part of the code space where there is no higher level controlled communication, scheduling that part of the code space for base station controlled communication.
In the present invention the metlud is applied to a cellular radio system in which two types of channel are present; one controlled by the basestation and a second by a higher level entity, whereby the same code space is allocated to both channels and the basestation uses the codes, only after checking that they are not being used by the higher level entity.
Preferably, at any time, the part of the code space not scheduled for higher level controlled communication is contiguous with code space permanently allocated only for base station controlled communication.
The most efficient arrangement is that the channels controlled by the higher layer entity are ordered contiguously in the code domain and the higher layer entity uses the codes in a manner that ensures a contiguous set of codes are available to the basestation.
Preferably, the terminal is informed via the higher level controlled channel that the same code space is used by the base station controlled channel, such that the terminal can switch between the higher level controlled channel and the base station controlled channel without reconfiguration of a physical layer of the terminal.
The terminal may be informed when using the channel controlled from the higher layer entity that the same codes are used for the second channel controlled by the ba.sestation, in order that it does not need to reconfigure its physical layer if it switches between the two channels Preferably, the communication system is a code division multiple access based cellular radio system.
Preferably, the system comprises a universal terrestrial radio access network frequency division duplex system.
Preferably, the higher level entity is a radio network controller.
Preferably, the base station controlled channel comprises a high speed downlink shared channel.
Preferably, the higher level entity controlled channel comprises a secondary common control physical channel.
The present invention enables a more optimal usage of the code space that does not involve wastage of S-CCPCH codes.
An example of a method of scheduling resources in a communication system will now be described with reference to the accompanying drawings in which: Fig. 1 is a block diagram of a system to which the method of the present invention can be applied; Fig. 2 illustrates a first example of the arrangement of code space for the method of the present invention; and, Fig. 3 illustrates a second example of the arrangement of codes space for the method of the present invention.
Fig.1 shows a communication system in which one or more terminals TI, T2 are variously controlled by a base station 1, or from a higher level entity than the base station, typically part of a network 2. Figs. 2 and 3 illustrate example s of how, in accordance with the present invention, a radio resource controller (RRC) 3 in the network 2 maps a group of orthogonal variable spreading factor (OVSF) codes 4 for both a secondary common control physical channel (S-CCPCH) 12, 14 and a high speed downlink shared channel (HS-DSCH) ii, 13. The group of OVSF codes are split between P-CCPCH and F-DPCH 5, HS-DSCH 6 and S-CCPCH 7. The S-CCPCH codes 7 are further subdivided into smaller code spaces 8, 9, 10.
A scheduler in the base station, or node B I, considers whether there is currently a transmission ongoing on the S-CCPCH 12, 14 for whichever terminal Ti, T2 the base station is scheduling (the S-CCPCH has a longer Ti'! than HS-DSCH, i.e. in the order of 10-4Omsec), or the scheduler determines whether the RNC has sent forward access channel (FACH) data that is imminently to be transmitted on the S-CCPCH. If the S-CCPCH is in use, or about to be in use, then the codes 8, 9, 10 are not available to used for HS-DSCH. If, however the S-CCPCH is not in use, then the Node B scheduler may schedule and send HS-DSCH data on the associated codes.
The S-CCPCH codes 8, 9, 10 are allocated and used in such a manner that a contiguous set of HS-DSCH codes are available to the Node B scheduler, if some, or all of the S-CCPCH codes are available. This can be seen in Fig.3. In Fig.3, when the RNC 3 has data to send on one of the S-CCPCH; then S-CCPCHI 1OA is selected in preference to S-CCPCH2 9, or S-CCPCH3 8, in order that the set of codes 6, 8A, 9A, available to the HS-DSCH remains contiguous. Maintenance of a contiguous set of MS-DSCH codes is useful to the Node B scheduler due to the signalling mechanism used on HS-SCCH.
To reduce re-configuration time, CELL.FACH users are made aware that the S-CCPCH codes are re-used for HS-DSCH and of any additional HS-DSCH codes. Thus, switching to CELL_DCH state does not require a re-configuration of the physical layer receivers in the terminal, or user equipment (UE), Ti, T2.
The present invention allows for re-use of the code space between S-CCPCH and HS-DSCH and faster reconfiguration between CELL_FACH and CELL_DCH states without incurring the system performance penalties described above, i.e. short iTT removing time diversity and larger signalling overhead due to lack of power control. If the option for allowing for fast reconfiguration between the states is not considered, then the re-use of the S-CCPCH codes can be implemented in the standard with no impact for existing Release 5 and 6 terminals.
For the purpose of this example, the radio system is UTRAN FDD, the first channel is the S-CCPCH controlled from the RNC and received by terminals in CELL_FACH state and the second the HS-DSCH, controlled from the basestation and received by users in CELL_FACH state. However, the names of the channels in use and the specific higher level entity may be different in other systems, for example universal terrestrial radio access (UTRA) time division duplex (TDD), time division.
synchronous code division multiple access (TD-SCDMA), or CDMA2000 and the invention is not limited to the specific example described, but is applicable to any communication system operating in a similar manner.

Claims (8)

1. A method of scheduling resources in a communication system comprising a terminal, a base station and a higher level entity than the base station; the method comprising allocating code space for users of a channel controlled by the base station and allocating the same code space for users of a channel controlled by the higher level entity determining whether there is ongoing or imminent higher level controlled communication in each part of the code space and for any part of the code space where there is no higher level controlled communication, scheduling that part of the code space for base station controlled communication.
2. A method according to claim I, wherein at any time, the part of the code space not scheduled for higher level controlled communication is contiguous with code space permanently allocated only for base station controlled communication.
3. A method according to claim 1 or claim 2, wherein the terminal is informed via the higher level controlled channel that the same code space is used by the base station controlled channel, such that the terminal can switch between the higher level controlled channel and the base station controlled channel without reconfiguration of a physical layer of the terminal.
4. A method according to any preceding claim, wherein the communication system is a code division multiple access based cellular radio system.
5. A method according to any preceding claim, wherein the system comprises a universal terrestrial radio access network frequency division duplex system.
6. A method according to any preceding claim, wherein the higher level entity is a radio network controller.
7. A method according to any preceding claim, wherein the base station controlled channel comprises a high speed downlink shared channel.
8. A method according to any preceding claim, wherein the higher level entity controlled channel comprises a secondary common control physical channel.
GB0620921A 2006-10-23 2006-10-23 Method of scheduling resources in a communication system Withdrawn GB2447251A (en)

Priority Applications (2)

Application Number Priority Date Filing Date Title
GB0620921A GB2447251A (en) 2006-10-23 2006-10-23 Method of scheduling resources in a communication system
PCT/GB2007/050637 WO2008050152A1 (en) 2006-10-23 2007-10-16 A method of scheduling resources in a communication system

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
GB0620921A GB2447251A (en) 2006-10-23 2006-10-23 Method of scheduling resources in a communication system

Publications (2)

Publication Number Publication Date
GB0620921D0 GB0620921D0 (en) 2006-11-29
GB2447251A true GB2447251A (en) 2008-09-10

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Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
ES2356211B1 (en) 2009-02-26 2012-02-15 Vodafone España, S.A.U. PROCEDURE FOR DYNAMIC ADJUSTMENT OF THE NUMBER OF HS-SCCH CHANNELS TO BE USED ON A CELL.

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2001030105A1 (en) * 1999-10-20 2001-04-26 Nokia Corporation Channel set-up in wideband, code division multiple access systems
EP1189375A1 (en) * 2000-09-12 2002-03-20 Lucent Technologies Inc. Dynamic reassignment of code space among multiple modes of operation
EP1235368A1 (en) * 2001-02-26 2002-08-28 Lucent Technologies Inc. Division of code space in mixed-service CDMA systems
GB2381711A (en) * 2001-10-31 2003-05-07 Lucent Technologies Inc A method of allocating a CDMA code to one of a group of user terminals
GB2382275A (en) * 2001-08-11 2003-05-21 Samsung Electronics Co Ltd Transmitting/receiving information about orthogonal variable spreading factor codes assigned to user data in a data packet access communication system
WO2003107707A1 (en) * 2002-06-13 2003-12-24 Nokia Corporation Method, system, and network entity, for adaptive reservation of channelization codes and power

Family Cites Families (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
ATE368993T1 (en) * 2003-08-11 2007-08-15 Alcatel Lucent METHOD FOR DYNAMIC ASSIGNMENT OF CDMA CODES TO A BASE STATION
CN100508437C (en) * 2003-12-22 2009-07-01 上海贝尔阿尔卡特股份有限公司 Method of dynamic channel code management for high-speed downlink shared channel
GB2420938B (en) * 2004-12-06 2007-04-04 Motorola Inc A cellular communication system, a base station and a method of resource allocation

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2001030105A1 (en) * 1999-10-20 2001-04-26 Nokia Corporation Channel set-up in wideband, code division multiple access systems
EP1189375A1 (en) * 2000-09-12 2002-03-20 Lucent Technologies Inc. Dynamic reassignment of code space among multiple modes of operation
EP1235368A1 (en) * 2001-02-26 2002-08-28 Lucent Technologies Inc. Division of code space in mixed-service CDMA systems
GB2382275A (en) * 2001-08-11 2003-05-21 Samsung Electronics Co Ltd Transmitting/receiving information about orthogonal variable spreading factor codes assigned to user data in a data packet access communication system
GB2381711A (en) * 2001-10-31 2003-05-07 Lucent Technologies Inc A method of allocating a CDMA code to one of a group of user terminals
WO2003107707A1 (en) * 2002-06-13 2003-12-24 Nokia Corporation Method, system, and network entity, for adaptive reservation of channelization codes and power

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WO2008050152A1 (en) 2008-05-02
GB0620921D0 (en) 2006-11-29

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