Patent Application
20140348040
The present invention relates to a semi-full-duplex single-carrier transmission technique. More specifically, the present invention relates to measures (including methods, apparatuses and computer program products) for enabling a semi-full-duplex single-carrier transmission technique.
In the field of communication systems, including wireless and/or cellular communication systems, various techniques are known for concurrently utilizing a physical channel for both transmitting and receiving operations, i.e. for communication in both transmitting and receiving directions from the viewpoint of a system entity in questions.
One of these known channel utilization techniques is Time Division Duplex (TDD) in which transmitting and receiving channels utilize a common frequency spectrum or carrier while being temporally separated from each other. The TDD technique is effective by offering flexible deployments without requiring a pair of spectrum resources, which is especially beneficial in wireless communication systems having limited spectrum resources. Further, the TDD technique is effective by allowing an asymmetric uplink-downlink (UL-DL) resource allocation in that a different number of resources (e.g. blocks, frames, subframes or the like) are allocated for uplink and downlink communications. In view of these features, TDD is currently utilized in various communication systems, including wireless and/or cellular communication systems, e.g. LTE, LTE-A and WiMAX.
When all system entities communicating with each other use TDD as the channel utilization technique, the thus adopted transmission technique is a half-duplex transmission technique. That is, while the same frequency spectrum or carrier is used for transmitting and receiving operations at each system entity, it is not feasible to simultaneously transmit and receive on the same frequency spectrum or carrier at the same time.
In terms of channel utilization efficiency, it would however be preferable to enable simultaneous transmitting and receiving operations on the same frequency spectrum or carrier at the same time. When all system entities communicating with each other could use such channel utilization technique, the thus adopted transmission technique would be a full-duplex transmission technique.
The full-duplex transmission technique has been known to be feasible in theory for some time, but it has been deemed to be unfeasible in practice so far. Specifically, the full-duplex transmission has been deemed to be an unfeasible concept for mobile communications and device deployments because the device's own transmit signal leaks into its own receiver chain causing problems in detection of wanted signals. Although interference cancellation schemes and other baseband signal processing operations have been constantly developed during the recent years, practically implementing full-duplex transmission is still a huge challenge from the point of view of conventional cellular systems and cellular devices.
While there are recent proposals for achieving full-duplex transmission on the same carrier, there remain challenging problems in terms of complexity of protocol and/or system design. Namely, in a full-duplex transmission technique, at least scheduling and interference cancellation at the communicating system entities, such as eNB and UE, would be highly complicated to be realized.
In view thereof, it is desirable to improve channel utilization efficiency or spectrum efficiency (as compared with a half-duplex transmission technique) while avoiding excessive complexity of protocol and/or system design e.g. in terms of at least scheduling and interference cancellation (as compared with a full-duplex transmission technique).
Thus, there is a desire to improve existing channel utilization techniques or duplex transmission techniques, particularly for single-carrier communications.
Various exemplary embodiments of the present invention aim at addressing at least part of the above issues and/or problems and drawbacks.
Various aspects of exemplary embodiments of the present invention are set out in the appended claims.
According to an exemplary aspect of the present invention, there is provided a method comprising classifying each one of served terminals into one of two transmission groups, assigning an uplink-downlink configuration of a frame structure for time division duplex communication for each one of the two transmission groups such that uplink subframes for one transmission group and downlink subframes of the other transmission group coincide with each other, and scheduling uplink and downlink transmissions for the served terminals on a single carrier according to the assigned uplink-downlink configurations for the two transmission groups.
According to an exemplary aspect of the present invention, there is provided a method comprising identifying classification into one of two transmission groups of terminals being served by a serving access node or base station, setting an uplink-downlink configuration of a frame structure for time division duplex communication according to the identified transmission group classification, wherein the set uplink-downlink configuration is such that uplink subframes coincide with downlink subframes of the other transmission group and downlink subframes coincide with uplink subframes of the other transmission group, and scheduling uplink and downlink transmissions on a single carrier according to the set uplink-downlink configuration.
According to an exemplary aspect of the present invention, there is provided an apparatus comprising at least one processor, at least one memory including computer program code, and at least one interface configured for communication with at least another apparatus, the at least one processor, with the at least one memory and the computer program code, being configured to cause the apparatus to perform: classifying each one of served terminals into one of two transmission groups, assigning an uplink-downlink configuration of a frame structure for time division duplex communication for each one of the two transmission groups such that uplink subframes for one transmission group and downlink subframes of the other transmission group coincide with each other, and scheduling uplink and downlink transmissions for the served terminals on a single carrier according to the assigned uplink-downlink configurations for the two transmission groups.
According to an exemplary aspect of the present invention, there is provided an apparatus comprising at least one processor, at least one memory including computer program code, and at least one interface configured for communication with at least another apparatus, the at least one processor, with the at least one memory and the computer program code, being configured to cause the apparatus to perform: identifying classification into one of two transmission groups of terminals being served by a serving access node or base station, setting an uplink-downlink configuration of a frame structure for time division duplex communication according to the identified transmission group classification, wherein the set uplink-downlink configuration is such that uplink subframes coincide with downlink subframes of the other transmission group and downlink subframes coincide with uplink subframes of the other transmission group, and scheduling uplink and downlink transmissions on a single carrier according to the set uplink-downlink configuration.
According to an exemplary aspect of the present invention, there is provided a computer program product comprising computer-executable computer program code which, when the program is run on a computer (e.g. a computer of an apparatus according to any one of the aforementioned apparatus-related exemplary aspects of the present invention), is configured to cause the computer to carry out the method according to any one of the aforementioned method-related exemplary aspects of the present invention.
Such computer program product may comprise or be embodied as a (tangible) computer-readable (storage) medium or the like on which the computer-executable computer program code is stored, and/or the program may be directly loadable into an internal memory of the computer or a processor thereof.
Advantageous further developments or modifications of the aforementioned exemplary aspects of the present invention are set out in the following.
By way of exemplary embodiments of the present invention, there is provided a semi-full-duplex single-carrier transmission technique (in/for cellular communication systems). More specifically, by way of exemplary embodiments of the present invention, there are provided measures and mechanisms for enabling a semi-full-duplex single-carrier transmission technique (in/for cellular communication systems).
Thus, enhancements are achieved by methods, apparatuses and computer program products enabling a semi-full-duplex single-carrier transmission technique (in/for cellular communication systems).
For a more complete understanding of exemplary embodiments of the present invention, reference is now made to the following description taken in connection with the accompanying drawings in which:
Exemplary aspects of the present invention will be described herein below. More specifically, exemplary aspects of the present are described hereinafter with reference to particular non-limiting examples and to what are presently considered to be conceivable embodiments of the present invention. A person skilled in the art will appreciate that the invention is by no means limited to these examples, and may be more broadly applied.
It is to be noted that the following description of the present invention and its embodiments mainly refers to specifications being used as non-limiting examples for certain exemplary network configurations and deployments. Namely, the present invention and its embodiments are mainly described in relation to 3GPP specifications being used as non-limiting examples for certain exemplary network configurations and deployments. In particular, a LTE/LTE-Advanced communication system is used as a non-limiting example for the applicability of thus described exemplary embodiments. As such, the description of exemplary embodiments given herein specifically refers to terminology which is directly related thereto. Such terminology is only used in the context of the presented non-limiting examples, and does naturally not limit the invention in any way. Rather, any other network configuration or system deployment, etc. may also be utilized as long as compliant with the features described herein, such as e.g. WiMAX and other systems.
Hereinafter, various embodiments and implementations of the present invention and its aspects or embodiments are described using several alternatives. It is generally noted that, according to certain needs and constraints, all of the described alternatives may be provided alone or in any conceivable combination (also including combinations of individual features of the various alternatives).
According to exemplary embodiments of the present invention, in general terms, there are provided mechanisms, measures and means for enabling a semi-full-duplex single-carrier transmission technique (in/for cellular communication systems).
In the following, exemplary embodiments of the present invention are described with reference to methods, procedures and functions, as well as with reference to structural arrangements and configurations.
As shown in
As shown in
Accordingly, the base station or access node realizes a full-duplex transmission technique (i.e. simultaneous transmitting and receiving operations on the same frequency spectrum or carrier at the same time), while the terminals or user equipments realize a half-duplex transmission technique (i.e. only transmitting or receiving operation on the same frequency spectrum or carrier at the same time).
In view thereof, exemplary embodiments of the present invention provide a semi-full-duplex single-carrier transmission technique, including a full-duplex single-carrier operation at a network entity side and a half-duplex single-carrier operation at a terminal entity side.
Hereinafter, procedures and functions relating to such semi-full-duplex single-carrier transmission technique according to exemplary embodiments of the present invention are described in more detail with reference to
As shown in
According to the above-outlined procedure, a full-duplex single-carrier operation at a network entity side may be realized.
As shown in
According to the above-outlined procedure, a half-duplex single-carrier operation at a terminal entity side may be realized.
From a system perspective, after the procedures according to
According to exemplary embodiments of the present invention, referring to the exemplary system scenario according to
According to exemplary embodiments of the present invention, multiple configurations, i.e. assignments of UL-DL configurations, may be designed to allow a different number of full-duplex subframes.
As shown in
In the exemplary configuration of
In Table 1 below, these specified UL-DL configurations are shown, wherein it is evident that the exemplary UL-DL configurations according to
According to exemplary embodiments of the present invention, a group-based UL-DL configuration assignment according to
As shown in
In the exemplary configuration of
As another example for UL-DL configurations for a transmission group classification according to exemplary embodiments, it may be assumed that that the UL-DL configuration assigned to UE group #1 has the subframe pattern DDUUUUDDDD, while the UL-DL configuration exemplarily assigned to UE group #2 has the subframe pattern UUDDDDUUUU.
According to exemplary embodiments of the present invention, a group-based UL-DL configuration assignment according to
According to exemplary embodiments of the present invention, the assigned uplink-downlink configurations for the two transmission groups comprise uplink-downlink configurations with a period of a predetermined number of subframes. That is to say, UL-DL configurations for a transmission group classification according to exemplary embodiments of the present invention may have any period.
As evident from a comparison of
As shown in
As evident from the scheduling example according to
As shown in
According to exemplary embodiments of the present invention, the reference sequence for each one of the two transmission groups comprises a primary or secondary synchronization signal (PSS/SSS).
In view thereof, an (automatic) group selection according to exemplary embodiments of the present invention on the basis of the procedure according to
The eNB may place and transmit two PSS/SSS or similar sequences in offseted subframes, i.e. subframes for different transmission times, one for each of the two groups. For example, referring to the exemplary configuration according to
According to exemplary embodiments of the present invention, a procedure according to
As shown in
In view thereof, an (automatic) group selection according to exemplary embodiments of the present invention on the basis of the procedure according to
The eNB should advantageously be able to dynamically change any UE's operating group (i.e. timing and DL/UL pattern) after an UE has connected to the network. To this end, the eNB may decide and signal a corresponding group index and/or a corresponding UL-DL configuration (i.e. subframe pattern) in a configuration signaling to the UE in question. Thereupon, the UE may identify the eNB-controlled UE group classification on the basis of the received group index when the UL-DL pattern is known implicitly or on the basis of the received UL-DL pattern.
According to exemplary embodiments of the present invention, the signaling may comprise sending a bitmap indication of the least one of the group index and the uplink-downlink configuration, or the signaling may comprise sending an indication of one of a predefined number of specified uplink-downlink configurations and an offset of a predetermined number of subframes.
In the case of a signaling based on a bitmap indication, a radio resource control (RRC) message or transmission may be used for signaling the respective information. Thereby, any freely/arbitrarily designed subframe patterns may be efficiently signaled, for example.
For example, such signaling may be accomplished in a pre-specified RRC information element, such as RadioResourceConfigDedicated. This may for example be realized as follows, assuming that a frame period of 8 subframes is adopted.
In the case of a signaling based on an indication of specified uplink-downlink configuration and offset, i.e. offset indication, the number of the specified uplink-downlink configuration and the offset in terms of a number of subframes may be signaled. Thereby, any pre-designed subframe patterns may be efficiently signaled, for example.
For example, referring to the exemplary configuration of
According to exemplary embodiments of the present invention, a procedure according to
In view of the above, exemplary embodiments of the present invention may provide the following beneficial technical effects.
Basically, a semi-full-duplex single-carrier transmission technique or system, including a full-duplex single-carrier operation at a network entity side and a half-duplex single-carrier operation at a terminal entity side, may be achieved.
In this regard, an improve channel utilization efficiency or spectrum efficiency (as compared with a half-duplex transmission technique) may be achieved, while avoiding excessive complexity of protocol and/or system design e.g. in terms of at least scheduling and interference cancellation (as compared with a full-duplex transmission technique). Also, significant performance gain can be expected in view of the network entity side is supporting full-duplex, while the complexity on the terminal entity side is not remarkably increased.
Further, the UL-DL configurations, i.e. subframe patterns, are configurable/adjustable, thereby enabling balancing between improvement in channel utilization efficiency or spectrum efficiency and increase in complexity. Accordingly, a flexible configuration scheme may be provided, which may also take into account factors regarding UL-DL asymmetry or the like.
Generally, the above-described procedures and functions may be implemented by respective functional elements, processors, or the like, as described below.
While in the foregoing exemplary embodiments of the present invention are described mainly with reference to methods, procedures and functions, corresponding exemplary embodiments of the present invention also cover respective apparatuses, network nodes and systems, including both software and/or hardware thereof.
Respective exemplary embodiments of the present invention are described below referring to
In
Further, in
In view of the above, the thus described apparatuses 10 and 20 are suitable for use in practicing the exemplary embodiments of the present invention, as described herein. The thus described apparatus 10 may represent a (part of an) network entity, such as a base station or access node, e.g. eNB of
According to exemplary embodiments of the present invention, any one of the thus illustrated apparatuses 10 and 20 may be operable in any conceivable wireless and/or cellular communication system, e.g. LTE, LTE-A and WiMAX, or the like.
An terminal entity according to exemplary embodiments of the present invention may for example comprise any (short range, cellular, satellite, etc.) wireless communication device such as car communication devices, mobile phones, smart phones, communicators, USB devices, laptops, finger computers, machine-to-machine terminals, device-to-device terminals, routers, terminals of pico/micro/femto cells and the like with wireless communication capability, and so on.
As indicated in
The processor 11/21 and/or the interface 13/23 may be facilitated for communication over a (hardwire or wireless) link, respectively. The interface 13/23 may comprise a suitable receiver or a suitable transmitter-receiver combination or transceiver, which is coupled to one or more antennas or communication means for (hardwire or wireless) communications with the linked or connected device(s), respectively. The interface 13/23 is generally configured to communicate with another apparatus, i.e. the interface thereof.
The memory 12/22 may store respective programs assumed to include program instructions or computer program code that, when executed by the respective processor, enables the respective electronic device or apparatus to operate in accordance with the exemplary embodiments of the present invention. For example, the memory 12/22 may store pre-specified or configured UL-DL configurations, information regarding the classification of terminal entities, and the like.
In general terms, the respective devices/apparatuses (and/or parts thereof) may represent means for performing respective operations and/or exhibiting respective functionalities, and/or the respective devices (and/or parts thereof) may have functions for performing respective operations and/or exhibiting respective functionalities.
When in the subsequent description it is stated that the processor (or some other means) is configured to perform some function, this is to be construed to be equivalent to a description stating that at least one processor, potentially in cooperation with computer program code stored in the memory of the respective apparatus, is configured to cause the apparatus to perform at least the thus mentioned function. Also, such function is to be construed to be equivalently implementable by specifically configured means for performing the respective function (i.e. the expression “processor configured to [cause the apparatus to] perform xxx-ing” is construed to be equivalent to an expression such as “means for xxx-ing”).
According to exemplary embodiments of the present invention, an apparatus representing the apparatus 10 comprises at least one processor 11, at least one memory 12 including computer program code, and at least one interface 13 configured for communication with at least another apparatus. The processor (i.e. the at least one processor 11, with the at least one memory 12 and the computer program code) is configured to perform classifying each one of served terminals into one of two transmission groups, assigning an uplink-downlink configuration of a frame structure for time division duplex communication for each one of the two transmission groups such that uplink subframes for one transmission group and downlink subframes of the other transmission group coincide with each other, and scheduling uplink and downlink transmissions for the served terminals on a single carrier according to the assigned uplink-downlink configurations for the two transmission groups.
According to exemplary embodiments of the present invention, the processor (i.e. the at least one processor 11, with the at least one memory 12 and the computer program code) may be configured to:
According to exemplary embodiments of the present invention, an apparatus representing the network entity 20 comprises at least one processor 20, at least one memory 22 including computer program code, and at least one interface 23 configured for communication with at least another apparatus. The processor (i.e. the at least one processor 21, with the at least one memory 22 and the computer program code) is configured to perform identifying classification into one of two transmission groups of terminals being served by a serving access node or base station, setting an uplink-downlink configuration of a frame structure for time division duplex communication according to the identified transmission group classification, wherein the set uplink-downlink configuration is such that uplink subframes coincide with downlink subframes of the other transmission group and downlink subframes coincide with uplink subframes of the other transmission group, and scheduling uplink and downlink transmissions on a single carrier according to the set uplink-downlink configuration.
According to exemplary embodiments of the present invention, the processor (i.e. the at feast one processor 21, with the at least one memory 22 and the computer program code) may be configured to perform:
As outlined above, for example, the uplink-downlink configurations for the two transmission groups may comprise subframe patterns of a predefined number of specified uplink-downlink configurations, which are offset against each other by a predetermined number of subframes, the uplink-downlink configurations for the two transmission groups may comprise arbitrarily designed subframe patterns, and the uplink-downlink configurations for the two transmission groups may comprise uplink-downlink configurations with a period of a predetermined number of subframes.
For further details of specifics regarding functionalities according to exemplary embodiments of the present invention, reference is made to the foregoing description in conjunction with
According to exemplarily embodiments of the present invention, a system may comprise any conceivable combination of the thus depicted devices/apparatuses and other network elements, which are configured to cooperate as described above.
In general, it is to be noted that respective functional blocks or elements according to above-described aspects can be implemented by any known means, either in hardware and/or software, respectively, if it is only adapted to perform the described functions of the respective parts. The mentioned method steps can be realized in individual functional blocks or by individual devices, or one or more of the method steps can be realized in a single functional block or by a single device.
Generally, any procedural step or functionality is suitable to be implemented as software or by hardware without changing the idea of the present invention. Such software may be software code independent and can be specified using any known or future developed programming language, such as e.g. Java, C++, C, and Assembler, as long as the functionality defined by the method steps is preserved. Such hardware may be hardware type independent and can be implemented using any known or future developed hardware technology or any hybrids of these, such as MOS (Metal Oxide Semiconductor), CMOS (Complementary MOS), BiMOS (Bipolar MOS), BiCMOS (Bipolar CMOS), ECL (Emitter Coupled Logic), TTL (Transistor-Transistor Logic), etc., using for example ASIC (Application Specific IC (Integrated Circuit)) components, FPGA (Field-programmable Gate Arrays) components, CPLD (Complex Programmable Logic Device) components or DSP (Digital Signal Processor) components. A device/apparatus may be represented by a semiconductor chip, a chipset, system in package, or a (hardware) module comprising such chip or chipset; this, however, does not exclude the possibility that a functionality of a device/apparatus or module, instead of being hardware implemented, be implemented as software in a (software) module such as a computer program or a computer program product comprising executable software code portions for execution/being run on a processor. A device may be regarded as a device/apparatus or as an assembly of more than one device/apparatus, whether functionally in cooperation with each other or functionally independently of each other but in a same device housing, for example.
Apparatuses and/or means or parts thereof can be implemented as individual devices, but this does not exclude that they may be implemented in a distributed fashion throughout the system, as long as the functionality of the device is preserved. Such and similar principles are to be considered as known to a skilled person.
Software in the sense of the present description comprises software code as such comprising code means or portions or a computer program or a computer program product for performing the respective functions, as well as software (or a computer program or a computer program product) embodied on a tangible medium such as a computer-readable (storage) medium having stored thereon a respective data structure or code means/portions or embodied in a signal or in a chip, potentially during processing thereof.
The present invention also covers any conceivable combination of method steps and operations described above, and any conceivable combination of nodes, apparatuses, modules or elements described above, as long as the above-described concepts of methodology and structural arrangement are applicable.
In view of the above, the present invention and/or exemplary embodiments thereof provide measures for enabling a semi-full-duplex single-carrier transmission technique. Such measures may exemplarily comprise classifying each one of served terminals into one of two transmission groups, assigning an uplink-downlink configuration of a frame structure for time division duplex communication for each one of the two transmission groups such that uplink subframes for one transmission group and downlink subframes of the other transmission group coincide with each other, and scheduling uplink and downlink transmissions for the served terminals on a single carrier according to the assigned uplink-downlink configurations for the two transmission groups.
Even though the present invention and/or exemplary embodiments are described above with reference to the examples according to the accompanying drawings, it is to be understood that they are not restricted thereto. Rather, it is apparent to those skilled in the art that the present invention can be modified in many ways without departing from the scope of the inventive idea as disclosed herein.
eNB evolved Node B (E-UTRAN base station)
WiMAX Worldwide Interoperability for Microwave Access
| Filing Document | Filing Date | Country | Kind | 371c Date |
|---|---|---|---|---|
| PCT/CN2011/084342 | 12/21/2011 | WO | 00 | 6/19/2014 |
