CN101253708A - Method for allocating CDMA channels - Google Patents

Abstract

A method for allocating CDMA channels applicable to a mobile communication system that performs communication by using two or more CDMA channels, the method comprising: for each active sector corresponding to a particular mobile station, independently allocating CDMA channels (i.e., frequency assignments) such that each active sector is allocated at least one CDMA channel; and transmitting packet data by using the allocated CDMA channel.

Description

Method for allocating CDMA channels

technical field

The present invention relates to a method for allocating CDMA channels, in particular to a method for allocating CDMA channels independently for each active sector.

Background technique

HRPD (High Speed Packet Data) is a standard for wireless (radio) access technology optimized for high-speed, high-capacity data transmission. The HRPD system applies Code Division Multiple Access (CDMA) technology and Time Division Multiplexing (TDM) technology to allow mobile stations to transmit data. Therefore, due to the improved data transmission rate and capacity of the HRPD system, it can provide multimedia content in applications in various technical fields, such as wireless Internet access, real-time road traffic information, wireless real-time broadcasting, movies, games, etc.

In order to send large volumes of data at a higher rate, the Nx HRPD system sends multiple packets when more than one CDMA channel is allocated to a mobile station (frequency allocation). That is, a method of transmitting packets by using multiple carriers is adopted.

According to the related art, in a system that transmits packets by using multiple carriers, active sectors are assigned the same CDMA channel (frequency assignment). That is, allocating CDMA channels (frequency allocation) to all other sectors in the same way as allocating CDMA channels to the serving sector (which is currently transmitting packet data to a particular mobile station) is problematic because from a radio resource management point of view It appears to be inefficient.

Also, in the related art, when data is transmitted by using the allocated CDMA channels (FA), it is not determined whether one of many CDMA channels (FA) should be used to transmit a control message. However, since control signals are considered more important than traffic data, there is a need to transmit such control signals in a more efficient manner.

Contents of the invention

The present invention has been developed to solve the above-mentioned problems of the related art. Accordingly, the present invention provides a method for allocating a CDMA channel (frequency allocation) to each active sector in a mobile communication system such as a HRPD (High Speed Packet Data) system in an efficient manner. Among the allocated CDMA channels, one can be selected and used for transmitting control signals.

Description of drawings

FIG. 1 shows a flowchart of an exemplary process for sending and receiving messages between a mobile station and a base station according to one embodiment of the present invention.

Figure 2 shows an example of an active sector with four sectors from three cells according to one embodiment of the invention.

FIG. 3 shows an example of a method of allocating CDMA channels (frequency allocation: FA) in an independent manner for each sector according to one embodiment of the present invention.

Detailed ways

An aspect of the present invention is the inventor's recognition of the problems and disadvantages of the related art described above and described in more detail below. Based on this recognition, the features of the present invention have been developed.

In order to solve the problems of the related art, the present invention provides a method for allocating a CDMA channel (frequency allocation) suitable for a mobile communication system that performs communication by using two or more CDMA channels, the The method comprises the steps of: for each active sector corresponding to a particular mobile station, independently assigning a CDMA channel (frequency assignment) such that each active sector is assigned at least one CDMA channel (frequency assignment); The CDMA channel (frequency allocation) to transmit packet data.

Various features and aspects of the present invention will be better understood from the following description taken in conjunction with the accompanying drawings. Referring to the drawings, some exemplary embodiments of the present invention will be described.

FIG. 1 shows a flowchart of an exemplary process for sending and receiving messages between a mobile station and a base station according to the present invention.

Referring to FIG. 1, a base station transmits information to a mobile station regarding the total number of frequency allocations (FA) (or CDMA channels) capable of handling high-speed data rate services. Here, information on the total number of CDMA channels (FA) may be transmitted via a sector parameter message (S11).

Table 1 below shows an embodiment of the sector parameter message used in the present invention.

[Table 1]

field Length (bits) MessageID 8 CountryCode 12 SectorID 128 SubnetMask 8 […] Channelcount 5

Channelcount appears in the following fields:

Channel count twenty four

[…]

reserve 0-7(according to need)

Referring again to FIG. 1, if the mobile station changes from the idle mode to the connected state, or if the active sector list is updated while in the connected state, the mobile station transmits information related to the active sectors to the base station. Information on active sectors may be sent via a routing update message (S12).

It should be noted that one cell can generally be divided into three areas (sections). An active sector can be defined as one or more areas of a single cell, or a combination of one or more areas of two or more different cells. An active sector may be said to have the strongest link to the mobile station. Such active sectors are defined to allow fast cell selection.

When fast cell selection (FCS) is used, the terminal (mobile station) recommends the best cell for downlink packet transmission and signals it to the network. The determination of the best cell may not be based solely on radio propagation conditions, but may take into account available resources (eg power and code space of cells in the active set). Different wireless systems differ from each other in terms of the actual implementation of fast cell selection, especially in terms of whether the terminal or the network determines the cell for the next downlink packet transmission. For example, in CDMA 2000 1×EV-DO the network follows the terminal’s recommendation, while in CDMA 2000 1×EV-DV the network also makes the determination taking into account available resources.

Table 2 below shows an embodiment of a routing update message according to the present invention.

[Table 2]

field Length (bits) MessageID 8 MessageSequence 8 ReferencePilotPN 9 ReferencePilotStrength 6 ReferenceKeep 1 NumPilots 4

NumPilots appears for the following fields:

field Length (bits) PilotPNPhase 15 ChannelIncluded 1 Channel 0 or 24 PilotStrength 6 Keep 1 reserve variable

Referring again to FIG. 1, upon receiving information on active sectors via a routing update message, the base station transmits CDMA channel (FA) allocation information for transmitting packet data to the mobile station. The CDMA channel (FA) allocation information may be transmitted via a traffic channel allocation message (S13).

Table 3 below shows an embodiment of the traffic channel assignment message.

[table 3]

field Length (bits) MessageID 8 MessageSequence 8 ChannelIncluded 1 Channel 0 or 24 FrameOffset 4 DRCLength 2 DRCChannelGainBase 6 ACKChannelGain 6 NumPilots 4

NumPilots appears for the following records:

PilotPN 9 Softer Handoff 1 MACIndexLSBs 6 DRCCover 3 RABLength 2 RAB Offset 3 RAChannelGainIncluded 0 or 1

NumPilots appears for the following fields:

RAChannelGain 0 or 2

MACIndexMSBsIncluded 0 or 1

NumPilots appears for the following fields:

MACIndexMSB 0 or 1 DSCChannelGainBase 0 or 5

The following fields appear 0 or N, where N is the number of SoftHandoff fields set to "0" in this message.

DSC 0 or 3 reserve variable

As can be seen from Table 3, a number of fields with different lengths (bits) are used to specify various parameters used in traffic channel allocation. Some of these fields will be explained in the context of the non-limiting embodiments described hereinafter. Specific fields that are not described in detail can still be clearly understood by those of ordinary skill in the art.

Figure 2 shows an example of an active sector with four sectors from three cells according to one embodiment of the invention. However, this is only exemplary as the number of cells and sectors can vary as required.

FIG. 3 shows an example of a method of allocating CDMA channels (frequency allocation: FA) in an independent manner for each sector according to one embodiment of the present invention. Figure 3 shows an exemplary method of how three CDMA channels (FA) are allocated to four active sectors.

In the embodiments of Figures 2 and 3, the active sectors for the mobile station have a first sector, a second sector, a third sector and a fourth sector (ie, sectors 1 to 4). As shown in Figure 3, a CDMA channel (FA) can be assigned independently for each active sector. That is, FA 1 and FA 2 may be allocated for sector 1, while FA 2 and FA 3 may be allocated for sector 2. It should be noted that the total number of CDMA channels (FA) allocated for each active sector may be different. That is, as shown in Figure 3, a total of two CDMA channels (FA) may be allocated for sectors 1 and 2, a single CDMA channel (FA) may be allocated for sector 3, and a total of three CDMA channels may be allocated for sector 4 (FA).

From a CDMA channel (frequency allocation) point of view, FA 1 is allocated to sectors 1, 3 and 4, FA 2 is allocated to sectors 1, 2 and 4, and FA 3 is allocated to sectors 2 and 4.

As described above, when CDMA channels (FA) are allocated independently for each active sector, the total number of CDMA channels (FA) that can be allocated for all active sectors is preset, and based on the channels of each sector or Load condition, the number of CDMA channels (FA) to be allocated can be determined from the total number of CDMA channels (FA). Although FIG. 5 depicts an exemplary method of allocating contiguous CDMA channels (FAs) for a single sector, CDMA channels (FAs), such as FA 1 and FA 3, may be allocated to a single sector in a discontinuous manner.

As described above, if a CDMA channel (FA) is independently assigned to each active sector, information related to the assignment of the CDMA channel (FA) needs to be transmitted to the mobile station. The FA allocation information to be transmitted may include information on all CDMA channels (FA) that can be allocated, information on the CDMA channel (FA) to be allocated to each sector, or information on the CDMA channel (FA) allocated to each sector. ) information about the sector. The FA assignment information may be sent via a traffic channel assignment message.

Table 4 below shows an embodiment of the traffic channel assignment message.

[Table 4]

field Length (bits) MessageID 8 MessageSequence 8 […] NumSectors 3 NumForwardChannels 4 […]

…………………………………………………

NumSectors appears in the following SectorInformation records:

[…] PilotPN 9 DRCCover 3 […]

……………………………………………

The following ActiveSetParameters records (starting at AssignedChannel (inclusive) and ending at MACIndex (inclusive)) appear NumForwardChannels:

{

Assigned channel 0 or 24 […] NumAssignedSectors 3

NumAssignedSectors appears for the following records:

{

AssignedSectorIndex 3 […] TrafficMACIndex 3 […] MACIndex 0 or 8

}

[…] reserve variable

The Traffic Channel Assignment message may include active sector assignment information for a specific mobile station and information on CDMA channels (FA) to be assigned to the active sector.

In the embodiment shown in Table 4, the NumSectors field represents information on the current number of active sectors for a specific mobile station. The NumForwardChannels field indicates the total number of CDMA channels (FA) allocated to all active sectors.

In addition, the traffic channel allocation message may include information related to each active cell (ie, information related to pilot PN codes and DRC coverage for each active sector). In the embodiment of Table 4, the information related to the PN code is represented by using the PilotPN field, and the information related to the DRC coverage is represented by using the DRCCover field.

In addition, the traffic channel assignment message may contain information about the active sectors assigned to each CDMA channel (FA). That is, in the embodiment shown in Table 4, the AssignedChannel field refers to a specific CDMA channel (FA). In addition, NumAssignedSectors refers to the number of sectors assigned to a specific CDMA channel (FA). And, the number (number) of information on active sectors corresponds to the total number of active sectors. In addition, in the embodiment of Table 4, the AssignedSectorIndex field indicates the active sector assigned to the specific CDMA channel (FA), and the TrafficMACIndex field refers to the index of the packet service with the mobile station assigned the CDMA channel (FA). The MAC index refers to a MAC index with power control of a reverse link to which a CDMA channel (FA) is allocated.

As with the embodiment of Table 4, based on the specific CDMA channel (FA), the traffic channel assignment message may include information related to each active sector having a specific CDMA channel (FA) assigned (i.e., AssignedSectorIndex in Table 4 ~ MACIndex), and information related to each active sector that has a specific CDMA channel (FA) assigned (ie, AssignedSectorIndex ~ MACIndex in Table 4).

By using the method described above, the traffic channel assignment message contains the information related to the CDMA channel (FA) of each CDMA channel (FA) (that is, AssignedChannel～NumAssignedSectors in Table 4), and the Information related to the active sector (that is, AssignedSectorIndex~MACIndex in Table 4).

By employing the traffic channel allocation message shown in Table 4, a CDMA channel (FA) allocation method such as the methods of FIGS. 2 and 3 can be expressed as follows.

First, the value of the NumSectors field is 4 because there are four active sectors with FA allocated. Since the total number of allocated FAs is 3, the value of the NumForwardChannels field is 3. Each of the four active sectors includes active sector information with a PilotPN field and a DRCCover field.

Also, first, an AssignedChannel field value corresponding to FA 1 is included. Since FA 1 is assigned to Sector 1, Sector 3, and Sector 4, the value of the NumAssignedSectors field is 3. At the same time, the values of the AssignedSectorIndex field to the MACIndex field are included to correspond to the total number of sectors with FA1 assigned. That is, the AssignedSectorIndex field to the MACIndex field are included for sector 1, sector 3, and sector 4.

Additionally, the AssignedChannel field value corresponding to FA 2 is included. Since FA 2 is assigned to Sector 1, Sector 2, and Sector 4, the value of the NumAssignedSector field is 3. At the same time, AssignedSectorIndex field ~ MACIndex field values are included to correspond to the total number of sectors with FA 2 assigned. That is, the AssignedSectorIndex field to the MACIndex field are included for sector 1, sector 2, and sector 4.

Additionally, the AssignedChannel field value corresponding to FA 3 is included. Since FA 3 is assigned to Sector 2 and Sector 4, the value of the NumAssignedSector field is 2. Meanwhile, AssignedSectorIndex field ~ MACIndex field values are included to correspond to the total number of sectors with FA3 assigned. That is, the fields AssignedSectorIndex to MACIndex are included for sector 2 and sector 4 .

As described above, although the traffic channel allocation message can be expressed using information on allocated sectors per CDMA channel (FA), it can also be expressed using information on allocated CDMA channels (FA) per sector.

As a result of the present invention, CDMA channels (frequency allocation: FA) are allocated independently to suit the conditions of each active sector, and thus, radio resources can be used more efficiently.

The present invention provides a method for allocating CDMA channels suitable for a mobile communication system, wherein the mobile communication system performs communication by using two or more CDMA channels, the method comprising the steps of: allocating CDMA channels in an independent manner channels, the allocation being performed for each active sector corresponding to a particular mobile station, wherein each active sector is respectively allocated at least one CDMA channel; and transmitting packet data using the allocated frequency allocation.

The method may also include the step of sending a message including information about two of the more channels and information about the active sector with the CDMA channel assigned. The message may be a Traffic Channel Assignment message. The traffic channel allocation message may include information related to the number of active sectors and the number of CDMA channels. The Traffic Channel Assignment message may also include Pilot PN information and DRC coverage information associated with each active sector. The Traffic Channel Assignment message may also include information about each CDMA channel, and information about active sectors that have one or more CDMA channels assigned to them. The traffic channel assignment message may also include information about each active sector, and information about each CDMA channel assigned to each active sector. The mobile communication system may be an Nx high-rate packet data system. A CDMA channel may be selected from a plurality of assigned CDMA channels and used to transmit forward link control signals.

Furthermore, the present invention provides a method for allocating a CDMA channel applicable to a mobile communication system which performs communication by using two or more CDMA channels for a mobile station, the method including the steps of: A first set of CDMA channels is assigned to a first sector of the mobile station's active sectors; a second set of CDMA channels is assigned to a second sector of the mobile station's active sectors; and packets are transmitted using the assigned CDMA channels.

The method may also include the step of sending a traffic channel assignment message including information about the assigned CDMA channel. The traffic channel assignment message may include: a first part, which includes information related to the number of active cells and the number of CDMA channels; a second part, which includes information on each active sector; and a third part, which includes information for each Information about the active sector for CDMA channel allocation. The traffic channel assignment message may include: a first part, which includes information related to the number of active cells and the number of CDMA channels; a second part, which includes information on each active sector; and a third part, which includes information for each Information about the CDMA channel allocated by the active sector. The method may further include the steps of: updating an active sector list including active sectors; and sending a traffic channel allocation message, wherein the traffic channel allocation message includes information of CDMA channels allocated for the updated active sectors. A CDMA channel may be selected from a plurality of assigned CDMA channels and used to transmit forward link control signals.

Furthermore, the present invention provides a method for allocating a CDMA channel applicable to a mobile communication system that performs communication by using two or more CDMA channels, the method including the steps of: receiving a traffic channel assignment message of channel-related information, wherein the CDMA channel is a CDMA channel independently assigned for each active sector corresponding to a particular mobile station; Receive packet data.

Furthermore, the present invention provides a mobile station comprising: a transceiver adapted to transmit and receive signals using a mobile communication network; and a processor adapted to receive information related to a traffic channel via the transceiver and Packet data is received from the network via the transceiver by using the traffic channel independently assigned by the network for each active sector corresponding to the mobile station based on the received information.

An active sector may refer to one or more areas of a single cell, or a combination of one or more areas of two or more different cells, and where the active sector has the strongest link to the mobile station and Allows fast cell selection. This information may be received from the network via a message indicating traffic channel allocation. The processor may cooperate with the transceiver to receive a message from the network indicating a total number of CDMA channels capable of handling high data rate service, wherein the receiving is performed prior to receiving a message indicating traffic channel assignments. If the mobile station changes from idle mode to connected state, or if the active sector list is updated in the connected state, in response to receiving a message indicating the total number of CDMA channels, the processor may cooperate with the transceiver to send to the network an active A message of sector information, wherein the sending is performed prior to receiving a message indicating a traffic channel assignment. The mobile communication network may be a CDMA network, and the traffic channels are CDMA channels. A traffic channel from a plurality of assigned traffic channels is independently selected by the network for each active sector and used to receive control signals.

It should be noted that the above features of the present invention relate to at least the 3GPP2 standard. That is, 3GPP2TSG-C WG3C.S0024-B and its relevant chapters and parts, as well as various improvements under development of the present invention all belong to the present invention. The features of the invention are described by using specific terms and notations. However, it is to be clearly understood that such designations and other terms are exemplary only, and thus may be changed (or clarified later) as a result of ongoing or future discussions.

Furthermore, the features of the present invention can be implemented in various products. A non-limiting example is a mobile station and/or network supporting cdma2000 1x EV-DO HRPD Rev. B. However, it is clearly understood that other embodiments are also possible.

This specification describes various exemplary embodiments of the invention. The scope of the claims is intended to cover various modifications and equivalent arrangements of the exemplary embodiments disclosed in the specification. Accordingly, the following claims should be construed in the broadest manner reasonably to cover modifications, equivalent structures, and features consistent with the spirit and scope of the invention disclosed herein.

Claims (25)

1. A method for allocating a CDMA channel applicable to a mobile communication system that performs communication by using two or more CDMA channels, the method comprising the steps of: allocating CDMA channels in an independent manner, said allocation being performed for each active sector corresponding to a particular mobile station, wherein each active sector is individually allocated at least one CDMA channel; and Packet data is transmitted using the allocated CDMA channel. 2. The method according to claim 1, further comprising the steps of: A message is sent including information about two of the more channels and information about the active sector to which said CDMA channel is assigned. 3. The method of claim 2, wherein the message is a Traffic Channel Assignment message. 4. The method according to claim 3, wherein the traffic channel allocation message includes information related to the number of active sectors and the number of CDMA channels. 5. The method of claim 4, wherein the traffic channel assignment message further includes pilot PN information and DRC coverage information associated with each active sector. 6. The method of claim 5, wherein the traffic channel assignment message further includes information about each CDMA channel, and information about the active sector to which one or more CDMA channels are assigned . 7. The method of claim 5, wherein the traffic channel assignment message further includes information about each active sector, and information about each CDMA channel assigned for each active sector. 8. The method of claim 1, said mobile communication system being an Nx high rate packet data system. 9. The method of claim 1, wherein a CDMA channel among a plurality of allocated CDMA channels is selected and used for transmitting forward link control signals. 10. A method for allocating a CDMA channel applicable to a mobile communication system that performs communication by using two or more CDMA channels, the method comprising the steps of: allocating a set of CDMA channels to a sector of the mobile station's active sectors; and Packet data is transmitted by using the allocated CDMA channel. 11. The method according to claim 10, further comprising the steps of: and sending a traffic channel assignment message including information about said assigned CDMA channel. 12. The method of claim 11, wherein the traffic channel assignment message comprises: The first part, the first part includes information related to the number of active cells and the number of CDMA channels; a second part that includes information for each active sector; and A third part, said third part including information of said active sectors allocated for each CDMA channel. 13. The method of claim 12, wherein the traffic channel assignment message comprises: The first part, the first part includes information related to the number of active cells and the number of CDMA channels; a second part that includes information for each active sector; and A third part that includes information on the CDMA channels assigned to each active sector. 14. The method of claim 10, further comprising the steps of: updating an active sector list to include the active sector; and Sending a traffic channel allocation message, where the traffic channel allocation message includes information about the CDMA channel allocated to the updated active sector. 15. The method of claim 10, wherein a CDMA channel is selected from a plurality of allocated CDMA channels and used for transmitting forward link control signals. 16. A method for allocating a CDMA channel applicable to a mobile communication system that performs communication by using two or more CDMA channels, the method comprising the steps of: receiving a traffic channel assignment message including information related to a CDMA channel that is independently assigned for each active sector corresponding to a particular mobile station; and Based on the received traffic channel assignment message, packet data is received from the base station by using the assigned CDMA channel. 17. A mobile station comprising: A transceiver suitable for transmitting and receiving signals using a mobile communication network; and a processor adapted to receive information related to a traffic channel via the transceiver and to receive packet data from the network via the transceiver using the traffic channel based on the received information, wherein the traffic A channel is a traffic channel independently assigned by the network for each active sector corresponding to the mobile station. 18. The mobile station of claim 17, wherein the active sector refers to one or more areas of a single cell, or a combination of one or more areas of two or more different cells, And wherein said active sector has the strongest link to said mobile station and allows fast cell selection. 19. The mobile station of claim 18, wherein the information is received from the network via a message indicative of a traffic channel assignment. 20. The mobile station of claim 19 , wherein said processor cooperates with said transceiver to receive a message from said network indicating the total number of CDMA channels capable of handling a high-speed data rate service, wherein upon receiving said Said receiving is performed prior to said message of traffic channel assignment. 21. The mobile station of claim 20, wherein said processor cooperates with said transceiver to send a message to said network comprising information of said active sector, wherein upon receiving said traffic channel assignment said The sending is performed before the message. 22. The method of claim 21, wherein the sending is performed in response to a received message indicating a total number of CDMA channels. 23. The method of claim 22, wherein said sending is performed if said mobile station changes from idle mode to connected state, or if said active sector list is updated in connected state. 24. The mobile station of claim 17, wherein the mobile communication network is a CDMA network and the traffic channel is a CDMA channel. 25. The method of claim 17, wherein a traffic channel is independently selected by the network from among a plurality of assigned traffic channels for each active sector and used to receive a control signal.