In order that the invention may be readily understood and put into practical effect, reference will now be made to exemplary embodiments as illustrated with reference to the accompanying figures, wherein like reference numbers refer to identical or functionally similar elements throughout the separate views. The figures together with a detailed description below, are incorporated in and form part of the specification, and serve to further illustrate the embodiments and explain various principles and advantages, in accordance with the present invention, where:
Skilled artisans will appreciate that elements in the figures are illustrated for simplicity and clarity and have not necessarily been drawn to scale. For example, the dimensions of some of the elements in the figures may be exaggerated relative to other elements to help to improve understanding of embodiments of the present invention.
According to one aspect, the present invention is a method for processing, in a wireless communication device, data concerning a group resource allocation. The method includes processing a group properties message received from a radio access network. The group properties message comprises group properties for a scheduling group, and the group properties comprise a group identifier that identifies the scheduling group. A group assignment message received from the radio access network is then processed. The group assignment message comprises the group identifier and a position assignment within the scheduling group. The group properties are then associated with the group assignment message.
Advantages of some embodiments of the present invention therefore include enabling efficient processing of control data, in the form of scheduling group control channel messages, concerning group radio frequency resource allocations. Control channel overhead can be reduced as group properties for multiple scheduling groups can be stored at an access terminal. Individual access terminals in a wireless communications network therefore can be efficiently assigned to a particular scheduling group. Such assignments may be based on various considerations such as improving overall network efficiency or improving a quality of service (QoS) for a particular access terminal. Access terminals further can be efficiently reassigned from one scheduling group to another, and the group properties of a group can be efficiently updated when, for example, network circumstances change.
Before describing in detail embodiments that are in accordance with the present invention, it should be observed that the embodiments reside primarily in combinations of method steps and apparatus components related to a method and system for processing group resource allocations. Accordingly, the apparatus components and method steps have been represented where appropriate by conventional symbols in the drawings, showing only those specific details that are pertinent to understanding the embodiments of the present invention so as not to obscure the disclosure with details that will be readily apparent to those of ordinary skill in the art having the benefit of the description herein.
In this document, relational terms such as first and second, top and bottom, and the like may be used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. The terms “comprises,” “comprising,” or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. An element preceded by “comprises a . . . ” does not, without more constraints, preclude the existence of additional identical elements in the process, method, article, or apparatus that comprises the element.
Referring to
The BSC 110 and the base stations 105 form a Radio Access Network (RAN). The RAN may comprise any number of BSCs 110, each controlling a number of base stations 105. The BSC 110 may alternatively be implemented as a distributed function among the base stations 105. Regardless of specific implementations, the BSC 110 comprises various modules for packetized communications, such as a packet scheduler module, packet segmentation and reassembly module, etc., and modules for assigning appropriate radio resources to the various ATs 125.
The base stations 105 can communicate with the ATs 125 via various standard air interfaces and using various modulation and coding schemes. For example, Universal Mobile Telecommunications System (UMTS), Evolved UMTS (E-UMTS) Terrestrial Radio Access (E-UTRA) or CDMA2000 schemes can be employed. Further, E-UMTS may employ Orthogonal Frequency Division Multiplexing (OFDM) and CDMA2000 may employ orthogonal spreading codes such as Walsh codes. Semi-orthogonal spreading codes also may be utilized to achieve additional channelization over the air interface. Further the network 100 can be an Evolved High Rate Packet Data (E-HRPD) network. Thus various appropriate radio interfaces may be employed in the network 100.
The BSC 110 is also operatively connected to a packet data serving node (PDSN) 130 that connects the BSC 110 to other internet protocol (IP) networks. Further, the BSC 110 is operatively connected to an IP multimedia subsystem (IMS) core 135 for supporting a range of IP-based services over both packet switched (PS) and circuit switched (CS) networks.
The BSC 110, the base stations 105, or some other network infrastructure component, can assign the ATs 125 to one or more scheduling groups for data transmission scheduling purposes. The ATs 125 may be grouped based on various factors such as radio channel quality or other conditions associated with the ATs 125. For example, such conditions can include channel quality information reported by the ATs 125, Doppler statistics reported by the ATs 125, and distance from a base station 105. Alternatively, or additionally, the ATs 125 may be grouped based on one or more access terminal operating characteristics other than participation in a common communication session. Exemplary mobile station operating characteristics include power headroom of an AT 125, macro diversity considerations, capability of an AT 125, service of an AT 125, and codec rate. Further, ATs 125 having an active VoIP session may be grouped together.
Referring to
Where the wireless communications network 100 employs orthogonal frequency division multiple access (OFDMA) technology, the frequency domain is divided into subcarriers. For example, a 5 MHz OFDMA carrier may be divided into 480 subcarriers, with a subcarrier spacing of 9.6 kHz. An OFDMA frame may be divided into multiple orthogonal frequency division multiplexing (OFDM) symbols. For example, a frame may occupy 0.91144 msec and contain 8 OFDM symbols, where each symbol occupies approximately 113.93 μsec. The subcarriers are then grouped to form block resource channels (BRCHs) and distributed resource channels (DRCHs). A BRCH is a group of contiguous subcarriers that may hop within a larger bandwidth, while a DRCH is a group of noncontiguous sub-carriers.
Referring to
Referring to
At arrows 455, a series of scheduling group control channel messages are sent and received between the AT 425 and the base station 405. According to some embodiments of the present invention, the scheduling group control channel messages enable the AT 425 to be grouped with other ATs to efficiently allocate limited radio frequency resources in the wireless communications network 400. As described in detail below, the scheduling group control channel messages may enable: 1) the AT 425 to be efficiently assigned to a scheduling group; 2) the AT 425 to be efficiently changed from one scheduling group to another; and 3) the properties of the scheduling group to which the AT 425 is assigned to be efficiently changed. As will be understood by those skilled in the art, the order of the scheduling group control channel messages associated with the arrows 455 can change according to various circumstances and embodiments of the present invention. Further, some of the scheduling group control channel messages can be deleted or repeated according to various circumstances and embodiments of the present invention.
Following the scheduling group control channel messages, at arrow 460, the IMS core 435 transmits a session initiation protocol (SIP) session in progress message to the AT 425. At arrow 465, the AT 425 then responds by transmitting an SIP provisional response acknowledgment (PRACK) message to the IMS core 435. Finally, at block 470, VoIP bearer traffic is transmitted between the AT 425 and the IMS core 435. The VoIP bearer traffic can be managed using, for example, physical layer and medium access control (PHY/MAC) bitmap signaling.
The scheduling group control channel messages associated with the arrows 455 are each described in detail below.
Referring to
The Time-Frequency Resource Information field 525 comprises several fields relating to the shared time-frequency resources assigned to a scheduling group. First, a Block Size field 530 is used to indicate the size of one block. A Number of Blocks field 535 is used to indicate the number of blocks assigned to a scheduling group. Where an OFDMA system is defined by logical blocks, where each block has an index, then a First Block field 540 is used to indicate an index of the first block assigned to a scheduling group. An Ordering Pattern field 545 is used to indicate an order in which resources are allocated. An Interlace Pattern field 550 is used to identify an interlace pattern associated with the scheduling group. For example, the Interlace Pattern field 550 may comprise radio frequency resource information including a starting frame and a frame spacing that identifies an interlace pattern.
A Group Resource Allocation Bitmap Information field 555 is used to convey information about a scheduling group resource allocation bitmap. In particular, a Bitmap Interpretation field 560 is used to show how the bitmap should be interpreted. A Bitmap Length field 565 is used to indicate a length of the bitmap itself A Bitmap Channel field 570 is used to indicate a channel (i.e., a set of blocks) on which the scheduling group resource allocation bitmap will be transmitted.
Finally, a Packet Information field 575 is used to indicate information about packets that will be transmitted to scheduling group members. A Modulation field 580 is used to indicate the modulation applied to the packets, while a Coding field 585 is used to indicate an encoder rate, puncturing pattern, or repetition of the packets. The fields of the GP message 500 as described above are intended to be exemplary in nature. It is understood that not all fields are necessary in all embodiments of the present invention, and that additional fields may be required in some cases. Also, the fields of the GP message 500 can be transmitted for one scheduling group at a time or can be transmitted for multiple scheduling groups at once.
Referring to
Referring to
When the base station 405 transmits a GP message 500, several ATs may then need to transmit a GPC message 700. It is generally not desirable for all ATs in a scheduling group to transmit a GPC message 700 at the same time. Therefore, according to some embodiments of the present invention, only ATs currently assigned to the scheduling group associated with the received GP message 500 will transmit a GPC message 700. Further, the ATs may wait an amount of time proportional to its assigned group position, which group position is described in detail below, before transmitting a GPC message 700. In this way, the various GPC messages 700 are distributed in the time domain. Also, according to some embodiments of the present invention, a GPC message 700 is transmitted to a radio access network, such as to the base station 405, only if the GPC message 700 contains an update to a current scheduling group.
Referring to
According to some embodiments of the present invention, the MAC ID field 830 is not transmitted as part of a payload of a GA message 800, but is rather used by the base station 405 to scramble and thus encode a GA message 800. In that way, each AT receiving a GA message 800 descrambles the message with its own MAC ID, but only a targeted AT, such as the AT 425, will be able to decode the GA message 800.
A Position ID field 835 can be used to indicate to the AT 425 its assigned group position within a scheduling group, such as a bitmap position. An Interlace Offset field 840 is used to indicate to the AT 425 in which long frame of an interlace pattern its first HARQ transmission will occur. The fields of a GA message 800 as described above are intended to be exemplary in nature. It is understood that not all fields are necessary in all cases, and that additional fields may be required in some cases. According to some embodiments of the present invention, the fields of a GP message 500 are also included in a GA message 800. In other embodiments of the present invention, the fields of a GP message 500 for multiple groups are also included in a GA message 800, and an AT can be assigned to multiple interlace offsets. This allows an access network to begin a new packet transmission for a particular AT in multiple interlace offsets, where there are multiple occurrences of the Position ID field 835 and the Interlace Offset field 840.
Referring to
If at block 920 it is determined that a GA message 800 having a GA Message Sequence indicated in a received GA Message Sequence field 810 has not been received in the last N seconds, then at block 930 it is determined whether a received GP Message Sequence field 815 and Group ID field 820 correspond to a GP Message Sequence and Group ID for a set of Group Properties in a memory of the AT 425. If so, then at block 935 a GAC message 1000 is transmitted to the base station 405. At block 940, the AT 425 begins receiving VoIP data using the Group Properties corresponding to the received Group ID field 820 and GP Message Sequence field 815 according to the Timing Field 822. However, if at block 930 it is determined that a received GP Message Sequence field 815 and Group ID field 820 do not correspond to a GP Message Sequence and Group ID for a set of Group Properties in a memory of the AT 425, then at block 945 the AT 425 transmits a Group Properties Request message 1100 to the base station 405.
Referring to
Referring to
According to some embodiments of the present invention, an AT such as the AT 425 also can request that its group assignment be changed from one group to another group. An AT may request that its group assignment be changed for various reasons including, for example, changes in radio channel conditions and movement of the AT relative to a base station. For example, a group change can be initiated by the AT 425 transmitting a Group Change Request (GCR) message 1200 to the base station 405. The base station 405 then transmits a Group Change (GC) message 1300 back to the AT 425.
Referring to
Referring to
Below are illustrative examples of the operation of the scheduling group control channel messages described above, according to some embodiments of the present invention. For purposes of brevity and clarity, some of the fields described above of the scheduling group control channel messages are deleted from and are not described in the present examples.
Consider that at time 0, the AT 425, having MAC ID ‘111100001111’, does not have any Group Properties stored in its memory. Further, at time 0, the base station 405 transmits a first GP message 500 having the following binary field values:
At time 0, the AT 425 successfully receives and processes the first GP message 500, so it stores the second through fourth values above in memory and transmits a Group Properties Complete (GPC) message 700 to the base station 405 with the following binary field values:
At time 1, the base station 405 transmits a second GP message 500 having the following binary field values:
At time 1, the AT 425 successfully receives and processes the second GP message 500, and determines that properties for Group ID ‘010’ do not already exist in memory, so it stores the second through fourth values above in memory and transmits a GPC message 700 to the base station 405 having the following binary field values:
At time 2, the base station 405 transmits a third GP message 500 having the following binary field values:
At time 2, the AT 425 successfully receives and processes the third GP message 500, and determines that properties for Group ID ‘001’ already exist in memory, as the properties for Group ID ‘001’ were already received with the first GP message 500. The AT 425 therefore replaces the memory contents associated with Group ID ‘001’ with the second through fourth values above and transmits a GPC message 700 to the base station 405 having the following binary field values:
For clarity, the arrows 455 of
At time 3, the base station transmits a fourth GP message 500 having the following binary field values:
At time 3, consider that the AT 425 does not receive the fourth GP message 500, so the AT 425 does not respond to the fourth GP message 500.
At time 4, the base station 405 transmits a Group Assignment (GA) message 800 to the AT 425 with MAC ID ‘111100001111’ having the following binary field values:
At time 4, the AT 425 successfully receives and processes the GA message 800, and determines that properties for Group ID ‘011’ and GP Message Sequence ‘100’ are not already stored in memory, therefore the AT 425 needs to obtain such properties from the base station 405 before the AT 425 can transmit a Group Assignment Complete (GAC) message 1000 to the base station 405. The AT 425 therefore transmits to the base station 405 a Group Properties Request (GPR) message 1100 having the following binary field values:
At time 5, in response to the GPR message 1100, the base station 405 retransmits the fourth GP message 500 having the following binary field values:
At time 5, the AT 425 successfully receives and processes the fourth GP message 500. The AT 425 is then able to begin receiving data according to the fourth GP message 500 and the GA message 800. The group properties for a first scheduling group identified by Group ID ‘001’ and the additional group properties for the additional scheduling groups identified by Group ID ‘010’ and Group ID ‘011’ are all stored in a memory of the wireless communication device. The AT 425 therefore transmits a Group Assignment Complete (GAC) message 1000 to the base station 405 having the following binary field values:
At time 6, the AT 425 transmits a Group Change Request (GCR) Message 1200 to the base station 405 having the following binary field values:
At time 7, the base station 405 then transmits a Group Change (GC) Message 1300 to the AT 425 having the following binary field values:
The examples above are intended to provide a concise illustration of a use of each of the scheduling group control channel messages described herein. Those skilled in the art will appreciate that the complete sequence of messages provided in the examples may not be applicable to actual working embodiments of the present invention.
It is sometimes necessary for an AT to be handed off from one base station (i.e., an original base station) to another base station (i.e., a new base station). The following is an example of how the messages described above are used to perform such a handoff. First, the AT indicates its desire to be handed off to the new base station, using a message, as is well known in the art. The new base station receives the message and assigns the AT temporary time-frequency resources for receiving data. The new base station then transmits a GP message 500, followed by a GA message 800. Note that the GP message 500 and the GA message 800 can be received from a radio access network in one message, as was previously described. The Timing field 822 of the GA message 800 is set to the index of a future superframe, so the AT knows when to stop using the temporary time-frequency resource and begin using shared time-frequency resources of a scheduling group assigned using the GA message 800. Under normal operation, the AT receives the GA message 800 and transmits a GAC message 1000 to the new base station. If the new base station receives the GAC message 1000, the new base station transmits data to the AT using the shared time-frequency resources of the scheduling group at the superframe corresponding to the Timing field 822 of the GA message 800. If the new base station does not receive the GAC message 1000 before the superframe index indicated in the Timing field 822 of the GA message 800, then the new base station transmits data to the AT on both the temporary time-frequency resources and the shared time-frequency resources of the scheduling group. The new base station then transmits another GA message 800. The process above is then repeated until the new base station receives a GAC message 1000, at which time the new base station discontinues transmitting data to the AT on the temporary time-frequency resources.
Referring to
At block 1425, a group assignment message received from the radio access network is processed. The group assignment message comprises a group identifier and a position assignment within a scheduling group. For example, the AT 425 receives from the base station 405 and processes a GA message 800. At block 1430, group properties received in one of the group properties messages for a group identified in the group assignment message are associated with the group assignment message. Such association can occur by comparing a group properties message sequence identifier included in the group assignment message with the message sequence identifier included in the group properties message; or by comparing the group identifier included in the group assignment message with the group identifier included in the group properties message. For example, a counter included in a GA message 800, such as the GP Message Sequence field 815, can be compared with the GP Message Sequence field 510 of a GP message 500. If the GP Message Sequence field 815 of a GA message 800 for a particular Group ID matches the GP Message sequence field 510 of a GP message 500, then the AT 425 knows that is has the current set of Group Properties for the scheduling group, such as those contained in the Time-frequency resource information field 525 in a GP message 500, and can begin receiving information on group resources according to the Timing field 822. At block 1435, a group assignment complete message is transmitted to the radio access network. For example, the AT 425 transmits a GAC message 1000 to the base station 405.
Referring to
Referring to
It is to be understood that
The memory 1615 comprises a computer readable medium that records the operating system 1620, the applications 1625, and the general file storage 1630. The computer readable medium also comprises computer readable program code components 1650 for processing data concerning a group radio frequency resource allocation. When the computer readable program code components 1650 are processed by the processor 1610, they are configured to cause the execution of the method 600, the method 900, the method 1400 or the method 1500 as described above, according to some embodiments of the present invention.
Referring to
Advantages of some embodiments of the present invention therefore include enabling efficient processing of control data, in the form of scheduling group control channel messages, concerning group radio frequency resource allocations. Control channel overhead can be reduced as group properties for multiple scheduling groups can be stored at an access terminal. Individual access terminals in a wireless communications network therefore can be efficiently assigned to a particular scheduling group. Such assignments may be based on various considerations such as improving overall network efficiency or improving a quality of service (QoS) for a particular access terminal. Access terminals further can be efficiently reassigned from one scheduling group to another, and the group properties of a scheduling group can be efficiently updated when, for example, network circumstances change.
It will be appreciated that embodiments of the invention described herein may be comprised of one or more conventional processors and unique stored program instructions that control the one or more processors to implement, in conjunction with certain non-processor circuits, some, most, or all of the functions of processing group resource allocations as described herein. The non-processor circuits may include, but are not limited to, a radio receiver, a radio transmitter, signal drivers, clock circuits, power source circuits, and user input devices. As such, these functions may be interpreted as steps of a method for processing group resource allocations. Alternatively, some or all functions could be implemented by a state machine that has no stored program instructions, or in one or more application specific integrated circuits (ASICs), in which each function or some combinations of certain of the functions are implemented as custom logic. Of course, a combination of the two approaches could be used. Thus, methods and means for these functions have been described herein. Further, it is expected that one of ordinary skill, notwithstanding possibly significant effort and many design choices motivated by, for example, available time, current technology, and economic considerations, when guided by the concepts and principles disclosed herein will be readily capable of generating such software instructions and programs and ICs with minimal experimentation.
In the foregoing specification, specific embodiments of the present invention have been described. However, one of ordinary skill in the art appreciates that various modifications and changes can be made without departing from the scope of the present invention as set forth in the claims below. Accordingly, the specification and figures are to be regarded in an illustrative rather than a restrictive sense, and all such modifications are intended to be included within the scope of the present invention. The benefits, advantages, solutions to problems, and any elements that may cause any benefit, advantage, or solution to occur or become more pronounced are not to be construed as critical, required, or essential features or elements of any or all of the claims. The invention is defined solely by the appended claims including any amendments made during the pendency of this application and all equivalents of those claims.