Patent Description:
This section is intended to provide a background or context to the invention disclosed below. The description herein may include concepts that could be pursued, but are not necessarily ones that have been previously conceived, implemented or described. Therefore, unless otherwise explicitly indicated herein, what is described in this section is not prior art to the description in this application and is not admitted to be prior art by inclusion in this section.

The principle on 'in resource' control (CTRL) signaling has been discussed in literature. A relevant background document is<NPL>. The main idea is to use embedded "on-the-fly" information to the users on its allocated time-frequency resources, as well as the additional information which is needed to decode the data. The physical layer (PHY) in-resource control channel (CCH) is mapped at the start of the resource allocation for the user in the first time symbol(s) and over a limited part of the frequency resources.

Another known concept is presented in LTE Rel-<NUM>, where PCFICH indicates the number of OFDMA symbols available for PDCCH/PHICH. PCFICH contains four different values: <NUM>, <NUM>, <NUM>, (and <NUM>, which is available only for the narrowband case). PDSCH starts from the next symbol indicated by PCFICH. For example, if two symbols are allocated for PDCCH (and indicated by PCFICH), PDSCH will start from the third OFDMA symbol. UE derives this info from PCFICH included in each subframe.

The current invention moves beyond these techniques.

Abbreviations that may be found in the specification and/or the drawing figures are either defined in the text or defined below after the detailed description section.

As discussed in detail below, the current invention maximizes the spectral efficiency of the system, by maximizing the number of data symbols within a subframe or transmission time interval (TTI).

Since the UL control plane may be one of the bottlenecks of hybrid beamforming architecture, this invention also includes multiple xPDCCH symbols with relatively low load to also maximize the resource usage efficiency at least in scenarios discussed herein.

In order to more effectively deal with the challenges inherent in future wireless communications system and overcome some of the disadvantages of the current state of affairs, exemplary embodiments of the current invention modify the usage of control resources for data transmission by focusing on reducing overhead of the control channel.

Assuming, for example, that one subframe includes <NUM> symbols, defining either <NUM> or <NUM> symbol downlink control block would mean <NUM>% or <NUM> % overhead from only downlink control symbols for the system (min is <NUM> % assuming one control symbol in each <NUM> symbol subframe).

Thus, in order to maximize the spectral efficiency of the system, the target is to maximize data symbols or enable maximizing number of data symbols within a subframe or TTI rather than saying minimizing control symbols. Considering the downlink control signaling that is used mainly for downlink and uplink grant signaling, and for uplink HARQ ACK/NACK feedback, the number of symbols required should be minimized.

However, it should be noted that in certain scenarios, overhead is not the only problem. Usage of two symbols may be needed also due to the limitations of RF beamforming. Capabilities of hybrid beamforming architecture are limited by eNB implementation.

A narrow RF beam can serve just one direction at a time. Hence, each UE requires typically dedicated beam resources; such that xPDCCH multiplexing capacity/symbol is limited by the number of Transmitter RF beams. In order to provide sufficient performance for xPDCCH at least two (X-pol) Transmitter RF beams are allocated by embodiments of this invention towards one UE transmitting xPDCCH. In practice the number of UEs/symbol may equal to the number of Transmitter RF beams/<NUM>. The number of Receiver RF beams available at eNB depends on the implementation.

On the other hand the number of UEs Receiving xPDCCH varies depending on the eNB scheduler decisions (covering both UL/DL).

To summarize, UL control plane may be one of the bottlenecks of hybrid beamforming architecture. For this reason, multiple xPDCCH symbols with relatively low load may be needed, at least in some scenarios. It would make sense to maximize the resource usage efficiency also in these scenarios.

Before turning to a further discussion of the current invention, we turn to <FIG>, which is a block diagram of one possible and non-limiting exemplary system in which the exemplary embodiments may be practiced.

Please note that the word "exemplary" is used herein to mean "serving as an example, instance, or illustration.

In <FIG>, a user equipment (UE) <NUM> is in wireless communication with a wireless network <NUM>. A UE is a wireless, typically mobile device that can access a wireless network. The UE <NUM> includes one or more processors <NUM>, one or more memories <NUM>, and one or more transceivers <NUM> interconnected through one or more buses <NUM>. The one or more buses <NUM> may be address, data, or control buses, and may include any interconnection mechanism, such as a series of lines on a motherboard or integrated circuit, fiber optics or other optical communication equipment, and the like. Note that the YYY module allows functionality for the usage of control resources for data transmission where any method or examples of such embodiments discussed herein can be practiced. The UE <NUM> includes a YYY module <NUM>, comprising one of or both parts <NUM>-<NUM> and/or <NUM>-<NUM>, which may be implemented in a number of ways. The YYY module <NUM> may be implemented in hardware as YYY module <NUM>-<NUM>, such as being implemented as part of the one or more processors <NUM>. The YYY module <NUM>-<NUM> may be implemented also as an integrated circuit or through other hardware such as a programmable gate array. In another example, the YYY module <NUM> may be implemented as YYY module <NUM>-<NUM>, which is implemented as computer program code <NUM> and is executed by the one or more processors <NUM>. For instance, the one or more memories <NUM> and the computer program code <NUM> may be configured to, with the one or more processors <NUM>, cause the user equipment <NUM> to perform one or more of the operations as described herein. The UE <NUM> communicates with eNB <NUM> via a wireless link <NUM>.

The eNB (evolved NodeB) <NUM> is a base station (e.g., for LTE, long term evolution, or <NUM> base station) that provides access by wireless devices such as the UE <NUM> to the wireless network <NUM>. The eNB <NUM> includes one or more processors <NUM>, one or more memories <NUM>, one or more network interfaces (N/W I/F(s)) <NUM>, and one or more transceivers <NUM> interconnected through one or more buses <NUM>. Note that the ZZZ module allows functionality for the usage of control resources for data transmission where any method or examples of such embodiments discussed herein can be practiced. The eNB <NUM> includes a ZZZ module <NUM>, comprising one of or both parts <NUM>-<NUM> and/or <NUM>-<NUM>, which may be implemented in a number of ways. The ZZZ module <NUM> may be implemented in hardware as ZZZ module <NUM>-<NUM>, such as being implemented as part of the one or more processors <NUM>. The ZZZ module <NUM>-<NUM> may be implemented also as an integrated circuit or through other hardware such as a programmable gate array. In another example, the ZZZ module <NUM> may be implemented as ZZZ module <NUM>-<NUM>, which is implemented as computer program code <NUM> and is executed by the one or more processors <NUM>. For instance, the one or more memories <NUM> and the computer program code <NUM> are configured to, with the one or more processors <NUM>, cause the eNB <NUM> to perform one or more of the operations as described herein. Two or more eNBs <NUM> communicate using, e.g., link <NUM>. The link <NUM> may be wired or wireless or both and may implement, e.g., an X2 interface.

The one or more buses <NUM> may be address, data, or control buses, and may include any interconnection mechanism, such as a series of lines on a motherboard or integrated circuit, fiber optics or other optical communication equipment, wireless channels, and the like. For example, the one or more transceivers <NUM> may be implemented as a remote radio head (RRH) <NUM>, with the other elements of the eNB <NUM> being physically in a different location from the RRH, and the one or more buses <NUM> could be implemented in part as fiber optic cable to connect the other elements of the eNB <NUM> to the RRH <NUM>.

It is noted that description herein indicates that "cells" perform functions, but it should be clear that the eNB that forms the cell would perform the functions. The cell makes up part of an eNB. That is, there can be multiple cells per eNB. For instance, there could be three cells for a single eNB carrier frequency and associated bandwidth, each cell covering one-third of a <NUM>-degree area so that the single eNB's coverage area covers an approximate oval or circle. Furthermore, each cell can correspond to a single carrier and an eNB may use multiple carriers. So if there are three <NUM>-degree cells per carrier and two carriers, then the eNB has a total of <NUM> cells.

The wireless network <NUM> may include a network control element (NCE) <NUM> that may include MME (Mobility Management Entity)/SGW (Serving Gateway) functionality, and which provides connectivity with a further network, such as a telephone network and/or a data communications network (e.g., the Internet). The eNB <NUM> is coupled via a link <NUM> to the NCE <NUM>. The link <NUM> may be implemented as, e.g., an S1 interface. The NCE <NUM> includes one or more processors <NUM>, one or more memories <NUM>, and one or more network interfaces (N/W I/F(s)) <NUM>, interconnected through one or more buses <NUM>. The one or more memories <NUM> and the computer program code <NUM> are configured to, with the one or more processors <NUM>, cause the NCE <NUM> to perform one or more operations.

Note that the virtualized entities that result from the network virtualization may still be implemented, at some level, using hardware such as processors <NUM> or <NUM> and memories <NUM> and <NUM>, and also such virtualized entities create technical effects.

The computer readable memories <NUM>, <NUM>, and <NUM> may be of any type suitable to the local technical environment and may be implemented using any suitable data storage technology, such as semiconductor based memory devices, flash memory, magnetic memory devices and systems, optical memory devices and systems, fixed memory and removable memory. The computer readable memories <NUM>, <NUM>, and <NUM> may be means for performing storage functions. The processors <NUM>, <NUM>, and <NUM> may be of any type suitable to the local technical environment, and may include one or more of general purpose computers, special purpose computers, microprocessors, digital signal processors (DSPs) and processors based on a multi-core processor architecture, as non-limiting examples. The processors <NUM>, <NUM>, and <NUM> may be means for performing functions, such as controlling the UE <NUM>, eNB <NUM>, and other functions as described herein.

In general, the various embodiments of the user equipment <NUM> can include, but are not limited to, cellular phones such as smart devices, tablets, personal digital assistants (PDAs) having wireless communication capabilities, portable computers having wireless communication capabilities, image capture devices such as digital cameras having wireless communication capabilities, gaming devices having wireless communication capabilities, music storage and playback appliances having wireless communication capabilities, internet appliances permitting wireless Internet access and browsing, tablets with wireless communication capabilities, as well as portable units or terminals that incorporate combinations of such functions. In addition, various embodiments of the user equipment include machines, communicators and categories of equipment, which are not primarily or not at all in use by human interaction.

In this invention, we show a new scheme to reduce DL control channel overhead of pre-<NUM> standard.

As seen in <FIG>, which is a time/frequency structure of DL subframe according to <NUM> pre-standard, the subframe contains one or two xPDCCH symbols: <NUM>/<NUM> % overhead (i.e. one or two out of <NUM> symbols). Frequency Division Multiplexing (FDM) between parallel xPDCCH channels is within each xPDCCH symbol. A minimum allocation unit for xPDCCH equals to <NUM> sub-carriers; <NUM> data sub-carriers (<NUM> bits assuming QPSK modulation); <NUM> pilot subcarriers (<NUM> per FDM layer).

In particular, item <NUM> represents the minimum control allocation unit <NUM> subcarriers. Item <NUM> represents <NUM> x <NUM> subcarriers. Item <NUM> represents the minimum data allocation unit <NUM> subcarriers. Item <NUM> represents <NUM> carrier <NUM> x <NUM> subcarriers. Item <NUM> represents downlink control of <NUM>-<NUM> OFDMA symbols. Item <NUM> represents downlink data of <NUM>-<NUM> OFDMA symbols.

A single user can have <NUM>, <NUM>, <NUM>, or <NUM> allocation unit(s).

A UE searches downlink control information (DCI) from both two symbols that can be mapped to xPDCCH. The search space is common for each symbol independently, which means that the UE shall monitor all the candidates for two symbols if not restricted by separate configuration or pre-determined rules.

As discussed earlier regarding 'in resource' CTRL signaling, the physical layer (PHY) in-resource control channel (CCH) is mapped at the start of the resource allocation for the user in the first time symbol(s) and over a limited part of the frequency resources, as shown in <FIG>, which illustrates the principle of in-resource CTRL signaling.

In particular, item <NUM> represents the in-resource control channel (CCH) with downlink scheduling grant, while item <NUM> represents the downlink data payload. Note the CCH content summary: UE identifier; PHY configuration for data payload; HARQ information; and MIMO information.

However, there are problems with this approach including that the UL grants require a specific solution and a UE blind detection burden may be an issue.

Regarding the other concept of LTE Rel-<NUM> discussed above, problems with the LTE approach include that each symbol is allocated either for data or control. Hence, the LTE Rel-<NUM> approach does not support multiplexing of control and data within a symbol.

In contrast to these methodologies, the current invention has the BS/system configuring the physical resources in at least two parts as shown in <FIG> and <FIG>, namely, (A) the resources available for control and data transmission and (B) the resources available for data transmission only. Such a configuration may be semi-static and be provided via higher layer control signaling (such as system information, or RRC signaling).

In <FIG>, item <NUM> represents a minimum frequency allocation unit. Items <NUM> and <NUM> represent the resources available for parts A and B respectively, namely, item <NUM> represents the resources available for control and data and item <NUM> represents the resources available for data. In <FIG>, the key therein defines those the unshaded blocks <NUM> as representing resources available for control and data and the shaded blocks <NUM> as representing resources available for data.

Parts A and B consist of multiple allocation units. An allocation unit consists of a predetermined amount of OFDMA symbols in time and subcarriers in frequency. An allocation unit may have different size in parts A and B).

The current invention has the BS allocating: DCIs into one or more allocation units for part A depending on the aggregation level; and data into one or more allocation units for both parts A and B or only for part B.

The UE monitors the DCI candidates for the part A.

The DCI contains information about data allocation in both parts A and B. Information of data allocation for part A may be inverse, such that it contains, for instance, a bitmap about allocation units used for CTRL (other signaling solutions can be used as well, for example, those which allow indicating one or multiple clusters of contiguous allocation units).

Then the UE derives the frequency domain allocation of data in part A based on the frequency allocation in part B and knowledge about allocation units used for CTRL in part A. The data transport block may be rate-matched around reserved CTRL control blocks in part A.

One exemplary embodiment of the invention has a separate DCI format to support the data transmission in part A. Utilizing separate DCIs keeps the DCI format size small, as in the case when there is no need to use part A for data transmission.

A further embodiment of the above exemplary embodiment has separate DCI formats to support data transmission is part A to limit usage of the DCI format for the subset of aggregation levels when the size of part A is small. For instance, a DCI format to support data transmission in part A where the size of part A is smaller than certain pre-determined size would be possible for n lowest aggregation levels from all aggregation levels m, where n < m (n e.g. <NUM> or <NUM>). Since high aggregation levels consume resource elements from part A, usage of part A for data REs (resource elements) with high aggregation levels may not provide improvement when part A has a limited number of REs. Correspondingly, in those cases, the blind decoding effort for the UE can be reduced.

In yet another example of an embodiment of the current invention, a beam switching gap is included between the 1st and the 2nd (or in general between consecutive) OFDMA symbols carrying DCI.

Another exemplary embodiment of the invention, as seen in <FIG>, allows flexible multiplexing between traffic having different QoS requirements. In this case, traffic having a higher QoS is transmitted similar to CTRL information. For example: multiplexing between UL CTRL and data with non-scheduled access; and multiplexing between URLCC and MBB in UL direction. In this case service having tighter latency requirement (e.g. URLCC (Ultra Reliable Low latency Communication)) is transmitted in region A and MBB (Mobile BroadBand) in region B and also in region A when URLCC is not exist. The UE monitors the URLCC candidates for the part A.

<FIG> shows an exemplary implementation of the invention on the top of pre-<NUM> standard. As can be seen from the key in <FIG>, lightly shaded blocks <NUM> represent data allocation while the darkly shaded block <NUM> represents control allocation. In the example of figure, only one allocation unit is allocated to CTRL respect to overhead of <NUM>% (<NUM>*<NUM>/(<NUM>*<NUM>). Overhead reduction can translated to <NUM> or <NUM> % throughput gain depending on the number of OFDMA symbols allocated to xPDCCH. The only change needed is to the signaling of allocation units used for CTRL. The signaling can realized by adding bitmap of <NUM> bits in the DCI or introducing additional DCI format to support data transmission in CTRL region. The bitmap required can be also compressed down to X bits e.g. down to <NUM> bits in such that each bit indicates two consecutive CTRL regions. Information about the potential RF beam switching gap may also be included in the DCI.

Embodiments herein may be implemented in software (executed by one or more processors), hardware (e.g., an application specific integrated circuit), or a combination of software and hardware. In an example of an embodiment, the software (e.g., application logic, an instruction set) is maintained on any one of various conventional computer-readable media. In the context of this document, a "computer-readable medium" may be any media or means that can contain, store, communicate, propagate or transport the instructions for use by or in connection with an instruction execution system, apparatus, or device, such as a computer, with one example of a computer described and depicted, e.g., in <FIG>. A computer-readable medium may comprise a computer-readable storage medium (e.g., <NUM>, <NUM>, or other device) that may be any media or means that can contain, store, and/or transport the instructions for use by or in connection with an instruction execution system, apparatus, or device, such as a computer. A computer-readable storage medium does not comprise merely propagating signals.

<FIG> is a logic flow diagram for dynamic segmentation, and illustrates the operation of an exemplary method <NUM>, a result of execution of computer program instructions embodied on a computer readable memory, functions performed by logic implemented in hardware, and/or interconnected means for performing functions in accordance with exemplary embodiments. Parts or all of method <NUM> could be performed in module YYY or module ZZZ as appropriate.

Step <NUM> depicts configuring physical resources in a wireless communication system into two parts for an allocation into one or more allocation units of (<NUM>) control information, depending on an aggregation level, for the first part, and (<NUM>) data for both the first part and the second part or only for the second part. Step <NUM> depicts receiving a signal comprising downlink control information and data. Step <NUM> depict, based on the received downlink control information, deriving the data allocation in the first part based on the data allocation in the second part and the control information allocation in the first part.

Without in any way limiting the scope, interpretation, or application of the claims appearing below, an advantage or a technical effect of one or more of the example embodiments disclosed herein is up to <NUM>% throughput gain without any blind decoding impacts. Another technical effect or advantage of one or more of the example embodiments disclosed herein is that application of the concepts has no impact to UE blind decoding burden. A still further advantage or technical effect of embodiments of the present invention is that it allows multiplexing control and data within the same symbol while maintaining the opportunity to ascertain part of control and data.

It is also noted herein that while the above describes example embodiments of the invention, these descriptions should not be viewed in a limiting sense. Rather, there are several variations and modifications which may be made without departing from the scope of the present invention as defined in the appended claims.

Claim 1:
A method performed by a mobile device, said method comprising:
receiving configuration information on physical resources in a wireless communication system, wherein the physical resources are configured into a first part and a second part, the first part comprising one or more allocation units for control information, depending on an aggregation level of resource elements, and data, and the second part comprising one or more allocation units for data;
receiving downlink control information in the first part and data transmission; and
based on the received downlink control information, deriving an allocation for the data transmission in the first part based on an allocation for the data transmission in the second part and on an allocation for the control information in the first part.