The present invention relates generally to wireless communication systems, and more particularly to a system and method for partitioning a resource in a wireless communications system.
Wireless communication systems are widely used to provide voice and data services for multiple users using a variety of access terminals such as cellular telephones, laptop computers and various multimedia devices. Such communications systems can encompass local area networks, such as IEEE 801.11 networks, cellular telephone and/or mobile broadband networks. The communication system can use one or more multiple access techniques, such as Frequency Division Multiple Access (FDMA), Time Division Multiple Access (TDMA), Code Division Multiple Access (CDMA), Orthogonal Frequency Division Multiple Access (OFDMA), Single Carrier Frequency Division Multiple Access (SC-FDMA) and others. Mobile broadband networks can conform to a number of system types or partnerships such as, General Packet Radio Service (GPRS), 3rd-Generation standards (3G), Worldwide Interoperability for Microwave Access (WiMAX), Universal Mobile Telecommunications System (UMTS), the 3rd Generation Partnership Project (3GPP), Evolution-Data Optimized EV-DO, or Long Term Evolution (LTE).
In an OFDMA communication system, the time-frequency resources of the system are shared among a plurality of mobile stations. The base station assigns resources to mobile stations using an assignment message, which is transmitted as part of a control channel. It is known to partition a set of resources into one or more resource partitions to facilitate resource allocation, control channel transmission, and the like. In prior art systems, however, the overhead associated with transmitting the resource partition information can be high.
As an additional example, in an FDD system with 8 subframes, the numbering of subframes for the DL can be 000, 001, 010, 011, 100, 101, 110, and 111, and the numbering of subframes for the UL can be 000, 001, 010, 011, 100, 101, 110, and 111.
In
Partitioning resources of a particular subframe into one or more partitions in order to enable different traffic types, reduces control channel overhead, enables fractional frequency reuse groups, etc. To partition the resources of a particular subframe, the BS transmits a subframe partition index to the set of mobile stations with which it is communicating in the subframe. The mobile stations then use this subframe partition index to determine their resource allocation or isolate their resource allocation to be contained within a particular resource partition.
The subframe partition scheme of
In accordance with an embodiment of the present invention, a method of operating a base station includes transmitting a first control channel to a user device. The first control channel has a subframe partition index that partitions resources of an associated subframe into at least one partition. The at least one partition has a size limited to only a set of possible partition sizes.
In accordance with another embodiment of the present invention, a method of operating a base station includes partitioning resources of an associated subframe into at least one partition, generating a subframe partition index from a set of equations configured to transform the at least one partition to a corresponding subframe index, and transmitting a first control channel to a user device. The first control channel includes the subframe partition index
In accordance with a further embodiment of the present invention, a wireless base station includes a transmitter configured to transmit a first control channel to a user device. The first control channel has a subframe partition index, which partitions resources of an associated subframe into at least one partition. The at least one partition has a size limited to only a set of possible partition sizes.
In accordance with an embodiment of the present invention, a wireless base station includes a transmitter configured to transmit a first control channel to a user device. The first control channel has a subframe partition index, which partitions resources of an associated subframe into at least one partition. The wireless base station is configured to generate the subframe partition index from a set of equations and the sizes of the at least one partition.
The foregoing has outlined rather broadly the features of an embodiment of the present invention in order that the detailed description of the invention that follows may be better understood. Additional features and advantages of embodiments of the invention will be described hereinafter, which form the subject of the claims of the invention. It should be appreciated by those skilled in the art that the conception and specific embodiments disclosed may be readily utilized as a basis for modifying or designing other structures or processes for carrying out the same purposes of the present invention. It should also be realized by those skilled in the art that such equivalent constructions do not depart from the spirit and scope of the invention as set forth in the appended claims.
For a more complete understanding of the present invention, and the advantages thereof, reference is now made to the following descriptions taken in conjunction with the accompanying drawing, in which:
Corresponding numerals and symbols in the different figures generally refer to corresponding parts unless otherwise indicated. The figures are drawn to clearly illustrate the relevant aspects of the embodiments and are not necessarily drawn to scale.
The making and using of various embodiments are discussed in detail below. It should be appreciated, however, that the present invention provides many applicable inventive concepts that can be embodied in a wide variety of specific contexts. The specific embodiments discussed are merely illustrative of specific ways to make and use the invention, and do not limit the scope of the invention.
The present invention will be described with respect to various embodiments in a specific context, namely resource management in wireless networks. The invention may also be applied to resource management in other types of networks. In embodiments of the present invention, memory efficient resource partitioning is provided.
Any set of limited partition sizes can be used. The ones described herein are only examples. For example, the possible partition sizes can be (0, 1, 2, 3, 4, 6, 10, and 16) for the case when there are 16 total subchannels. The candidate partition sizes can change based on the total number of subchannels. In some embodiments, the BS indicates which set of candidate partition sizes are being used in a broadcast control channel message, for example the broadcast message 605 of
In some embodiments, the control message 810 is transmitted in each DL subframe. The control message 810 may be repeated for DL traffic and UL traffic. In some embodiments, the control message 810 is transmitted every K subframes and the resource partitions are valid until the next occurrence of the control message 810.
Depending on the number of subchannels and the number of partitions, the number of combinations for partitioning the subchannels into the partitions can be large, potentially greater than 1000 combinations. Therefore, embodiment systems and methods provide a simple, memory efficient way, for the BS and MS to transform the partitions into a subframe partition index and visa versa. In one embodiment of the present invention, a set of equations are used to transform the partitions to the corresponding subframe partition index. At the BS side, the BS first determines the values of a, b, c, and d for the case when there are four partitions. The BS then uses the following procedures to transform a, b, c, and d into an index. The equations use 24 total subchannels for illustration, therefore it is implicit that d=24−a−d−c. The equations are valid of the scheme with resource partition sizes beginning at 0 and ending at the total number of resources, inclusive as in
The equations can be formulated into pseudo-code as follows:
It should be understood that the embodiment pseudo-code shown above can be implemented using a variety of different systems and methods including software of various languages, such as C++, or by hardware. For example, a hardware description language could be used to implement a hardware version of the above pseudo-code in some embodiments.
At the MS side, the procedures are reversed. The equations can be extended to any number of partitions and any total number of subchannels. In an embodiment, partitions are allocated at the BS and the MS determines the partitions based on received data from the BS, and the MS uses resources within only one of these partitions.
In the formulation below, the number of subchannels is defined as M and there are five partitions, a, b, c, d, and e. The output of the equations and pseudo code (result) is the subframe partition index, and the inputs are the sizes of the partitions. Because there are M subchannels, the number of subchannels in partition e is M−a−b−c−d.
The equations can be formulated into pseudo-code as follows:
Again, it should be understood that the embodiment pseudo-code shown above can be implemented using a variety of different systems and methods including software of various languages, such as C++, or by hardware. For example, a hardware description language could be used to implement a hardware version of the above pseudo-code in some embodiments.
A block diagram of an embodiment base station 1300 is illustrated in
A block diagram of an embodiment user device 1400 is illustrated in
Although present embodiments and its advantages have been described in detail, it should be understood that various changes, substitutions and alterations can be made herein without departing from the spirit and scope of the invention as defined by the appended claims. For example, many of the features and functions discussed above can be implemented in software, hardware, or firmware, or a combination thereof.
Moreover, the scope of the present application is not intended to be limited to the particular embodiments of the process, machine, manufacture, composition of matter, means, methods and steps described in the specification. As one of ordinary skill in the art will readily appreciate from the disclosure of the present invention, processes, machines, manufacture, compositions of matter, means, methods, or steps, presently existing or later to be developed, that perform substantially the same function or achieve substantially the same result as the corresponding embodiments described herein may be utilized according to the present invention. Accordingly, the appended claims are intended to include within their scope such processes, machines, manufacture, compositions of matter, means, methods, or steps.
This patent application claims priority to U.S. Provisional Application No. 61/118,000 filed on Nov. 26, 2008, entitled “Method and Apparatus for Partitioning a Resource in a Wireless Communication System,” which application is hereby incorporated by reference herein.
Number | Date | Country | |
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61118000 | Nov 2008 | US |