Patent Description:
Wireless communication devices have become smaller and more powerful in order to meet consumer needs and to improve portability and convenience. Consumers have become dependent upon wireless communication devices and have come to expect reliable service, expanded areas of coverage and increased functionality. A wireless communication system may provide communication for a number of wireless communication devices, each of which may be serviced by a base station. A base station may be a device that communicates with wireless communication devices.

As wireless communication devices have advanced, improvements in communication capacity, speed, flexibility and/or efficiency have been sought. However, improving communication capacity, speed, flexibility and/or efficiency may present certain problems.

For example, wireless communication devices may communicate with one or more devices using a communication structure. However, the communication structure used may only offer limited flexibility and/or efficiency. As illustrated by this discussion, systems and methods that improve communication flexibility and/or efficiency may be beneficial.

<CIT> discloses a method for transmitting an ACK/NACK signal for an HARQ (Hybrid Automatic Repeat request) in a CA (Carrier Aggregation) system. The method includes obtaining at least one transmission resource among first an second transmission resources. The document mentions that multi-access schemes applied to the wireless communication system are not limited.

<CIT> discloses a method for transmitting an acknowledgement/not-ackowledgement (ACK/NACK) of a terminal in a wireless communication system, and a terminal using the method. The method comprises the steps of: receiving uplink-downlink (UL-DL) setting information on a plurality of subframes; receiving data from at least one subframes from the plurality of the subframes; composing the ACK/NACK on the received data; and transmitting the ACK/NACK through the uplink subframe.

<CIT> discloses a method and a device for transmitting an acknowledgement/not-acknowledgement (ACK/NACK) of a terminal which is set with a plurality of serving cells. The method comprises the steps of: receiving data in a subframe n of a second serving cell; and transmitting an ACK/NACK signal for the data in a subframe n + kSCC(n) of a first serving cell connected to the subframe n of the second serving cell, wherein the first serving cell is a primary cell for the terminal to execute an initial connection establishment procedure or a connection reestablishment procedure, and uses a frequency division duplex (FDD) wireless frame, the second serving cell is a secondary cell allocated to the terminal in addition to the primary cell, and uses a time division duplex (TDD) wireless frame, and the kSCC(n) is a previously determined value.

A UE for performing carrier aggregation is disclosed. The UE includes a processor and memory that is in electronic communication with the processor. Executable instructions are stored in the memory. The UE determines an uplink control information (UCI) transmission cell in a wireless communication network with at least one FDD cell and at least one TDD cell. The UE also selects a first cell for FDD and TDD carrier aggregation. The UE further determines a set of downlink subframe associations for the first cell that indicate at least one UCI transmission uplink subframe of the UCI transmission cell. The UE additionally sends Physical Downlink Shared Channel (PDSCH) Hybrid Automatic Repeat Request Acknowledgement/Negative Acknowledgement (HARQ-ACK) information in the UCI transmission uplink subframe of the UCI transmission cell.

The UE may also determine a PDSCH scheduling for the first cell. The PDSCH scheduling may include cross-carrier scheduling. The scheduling of the first cell may be based on a scheduling cell timing. The PDSCH scheduling for the first cell may occur in a downlink allocation subframe of the scheduling cell. The scheduling cell may be a TDD cell. In one implementation not encompassed by the wording of the claims, the UE may also determine a Physical Uplink Shared Channel (PUSCH) scheduling and PUSCH HARQ-ACK associations for the first cell.

The set of downlink subframe associations for the first cell may include a PDSCH association timing of the UCI transmission cell. The UCI transmission cell may be a FDD cell and the first cell may be a TDD cell.

Determining the set of downlink subframe associations for the first cell may include maintaining a PDSCH association timing of the first cell. The UCI transmission cell may be a FDD cell and the first cell may be a TDD cell.

The UE may additionally determine a primary cell (PCell). In one implementation not encompassed by the wording of the claims, the PCell may be a TDD cell and the UCI transmission cell may be a reference cell. The reference cell may be a FDD cell.

The UE may also determine a second UCI transmission cell for UCI transmission. The UCI transmission cell and second UCI transmission cell may utilize different duplexing. The UE may additionally send PDSCH HARQ-ACK information in the UCI transmission uplink subframe of the UCI transmission cell. The PDSCH HARQ-ACK information for the FDD cell may be sent by the UCI transmission cell and the PDSCH HARQ-ACK information for the TDD cell may be sent by the second UCI transmission cell. The PDSCH HARQ-ACK information may be sent on one of a Physical Uplink Control Channel (PUCCH) or a PUSCH.

An eNB for performing carrier aggregation is also described. The eNB includes a processor and memory that is in electronic communication with the processor. Executable instructions are stored in the memory. The eNB determines an UCI transmission cell in a wireless communication network with at least one FDD cell and at least one TDD cell. The eNB also selects a first cell for FDD and TDD carrier aggregation. The eNB further determines a set of downlink subframe associations for the first cell that indicate at least one UCI transmission uplink subframe of the UCI transmission cell. The eNB additionally receives PDSCH HARQ-ACK information in the UCI transmission uplink subframe of the UCI transmission cell.

A method for performing carrier aggregation by a UE is also described. The method includes determining an UCI transmission cell in a wireless communication network with at least one FDD cell and at least one TDD cell. The method also includes selecting a first cell for FDD and TDD carrier aggregation. The method further includes determining a set of downlink subframe associations for the first cell that indicate at least one UCI transmission uplink subframe of the UCI transmission cell. The method additionally includes sending PDSCH HARQ-ACK information in the UCI transmission uplink subframe of the UCI transmission cell.

A method for performing carrier aggregation by an eNB is also described. The method includes determining an UCI transmission cell in a wireless communication network with at least one FDD cell and at least one TDD cell. The method also includes selecting a first cell for FDD and TDD carrier aggregation. The method further includes determining a set of downlink subframe associations for the first cell that indicate at least one UCI transmission uplink subframe of the UCI transmission cell. The method additionally includes receiving PDSCH HARQ-ACK information in the UCI transmission uplink subframe of the UCI transmission cell.

The 3rd Generation Partnership Project, also referred to as "3GPP," is a collaboration agreement that aims to define globally applicable technical specifications and technical reports for third and fourth generation wireless communication systems. The 3GPP may define specifications for next generation mobile networks, systems, and devices.

At least some aspects of the systems and methods disclosed herein may be described in relation to the 3GPP LTE, LTE-Advanced (LTE-A) and other standards (e.g., 3GPP Releases <NUM>, <NUM>, <NUM> and/or <NUM>). However, the scope of the present disclosure should not be limited in this regard. At least some aspects of the systems and methods disclosed herein may be utilized in other types of wireless communication systems.

A wireless communication device may be an electronic device used to communicate voice and/or data to a base station, which in turn may communicate with a network of devices (e.g., public switched telephone network (PSTN), the Internet, etc.). In describing systems and methods herein, a wireless communication device may alternatively be referred to as a mobile station, a UE, an access terminal, a subscriber station, a mobile terminal, a remote station, a user terminal, a terminal, a subscriber unit, a mobile device, etc. Examples of wireless communication devices include cellular phones, smart phones, personal digital assistants (PDAs), laptop computers, netbooks, e-readers, wireless modems, etc. In 3GPP specifications, a wireless communication device is typically referred to as a UE. However, as the scope of the present disclosure should not be limited to the 3GPP standards, the terms "UE" and "wireless communication device" may be used interchangeably herein to mean the more general term "wireless communication device.

In 3GPP specifications, a base station is typically referred to as a Node B, an eNB, a home enhanced or evolved Node B (HeNB) or some other similar terminology. As the scope of the disclosure should not be limited to 3GPP standards, the terms "base station," "Node B," "eNB," and "HeNB" may be used interchangeably herein to mean the more general term "base station. " Furthermore, the term "base station" may be used to denote an access point. An access point may be an electronic device that provides access to a network (e.g., Local Area Network (LAN), the Internet, etc.) for wireless communication devices. The term "communication device" may be used to denote both a wireless communication device and/or a base station.

It should be noted that as used herein, a "cell" may refer to any set of communication channels over which the protocols for communication between a UE and eNB that may be specified by standardization or governed by regulatory bodies to be used for International Mobile Telecommunications-Advanced (IMT-Advanced) or its extensions and all of it or a subset of it may be adopted by 3GPP as licensed bands (e.g., frequency bands) to be used for communication between an eNB and a UE. "Configured cells" are those cells of which the UE is aware and is allowed by an eNB to transmit or receive information. "Configured cell(s)" may be serving cell(s). The UE may receive system information and perform the required measurements on all configured cells. "Activated cells" are those configured cells on which the UE is transmitting and receiving. That is, activated cells are those cells for which the UE monitors the physical downlink control channel (PDCCH) and in the case of a downlink transmission, those cells for which the UE decodes a PDSCH. "Deactivated cells" are those configured cells that the UE is not monitoring the transmission PDCCH. It should be noted that a "cell" may be described in terms of differing dimensions. For example, a "cell" may have temporal, spatial (e.g., geographical) and frequency characteristics.

The systems and methods disclosed herein describe carrier aggregation. In some configurations, the systems and methods disclosed herein describe LTE enhanced carrier aggregation (eCA) with hybrid duplexing. For example, association timings are described for a case when a PCell is configured with frequency division duplexing (FDD) and a secondary cell (SCell) is configured with time division duplexing (TDD). Additionally, as another example not encompassed by the wording of the claims, association timings for a case when a PCell is configured with TDD and a SCell is configured with FDD are also described.

Currently, there are two LTE duplex systems, FDD and TDD. However, under current approaches, FDD and TDD systems cannot work together for CA. For example, under known approaches (e.g., LTE Rel-<NUM> (hereafter "Rel-<NUM>")) and proposed approaches (e.g., LTE Rel-<NUM> (hereafter "Rel-<NUM>")), carrier aggregation (CA) is allowed for either multiple FDD cells, or multiple TDD cells, but not a hybrid of both types of cells.

Carrier aggregation refers to the concurrent utilization of more than one carrier. In carrier aggregation, more than one cell may be aggregated to a UE. In one example, carrier aggregation may be used to increase the effective bandwidth available to a UE. The same TDD uplink-downlink (UL-DL) configuration has to be used for TDD CA in Rel-<NUM>, and for intra-band CA in Rel-<NUM>. In Rel-<NUM>, inter-band TDD CA with different TDD UL-DL configurations is supported. The inter-band TDD CA with different TDD UL-DL configurations may provide the flexibility of a TDD network in CA deployment. Furthermore, enhanced interference management with traffic adaptation (eIMTA) may allow flexible TDD UL-DL reconfiguration based on the network traffic load. However, CA in a hybrid duplexing network (e.g., a network with both FDD and TDD cells) is not supported in any current approach. It should be noted that the term "concurrent" and variations thereof as used herein may denote that two or more events may overlap each other in time and/or may occur near in time to each other. Additionally, "concurrent" and variations thereof may or may not mean that two or more events occur at precisely the same time.

A FDD cell requires spectrum (e.g., radio communication frequencies) in which contiguous subsets of the spectrum are entirely allocated to either UL or DL but not both. Accordingly, FDD may or may not have carriers that are paired (e.g., may DL than UL carriers). However, TDD may allocate UL and DL resources on the same carrier frequency. Therefore, TDD may provide more flexibility on spectrum usage. With the increase in wireless network traffic, and as spectrum resources become very precious, new allocated spectrum tends to be fragmented and has smaller bandwidth, which is more suitable for TDD and/or small cell deployment. Furthermore, TDD may provide flexible channel usage through traffic adaptation with different TDD UL-DL configurations and dynamic DL-UL re-configuration.

The systems and methods described herein include carrier aggregation (CA) under the same scheduler control, with a macro cell and a small cell (e.g., femtocell, picocell, microcell, etc.) heterogeneous network scenario. For the LTE network deployment, most carriers choose FDD-LTE; however, TDD-LTE is becoming more and more important in many markets. A TDD implementation may provide flexibility for small cells with fast traffic adaptation.

With TDD CA and hybrid duplexing networks, the macro cells and small cells may use different frequency bands. A frequency band is a small section of the spectrum, in which communication channels may be established. For example, in a typical CA case, the macro cell may use a lower frequency band and the small cell may use a higher frequency band. For hybrid duplexing networks, a possible combination is to have FDD on a macro cell and TDD on a small cell. Therefore, to allow seamless operation, two pairs of association timings are important for CA in a hybrid duplexing network: (<NUM>) Physical downlink shared channel (PDSCH) scheduling and PDSCH HARQ-ACK reporting, and (<NUM>) Physical uplink shared channel (PUSCH) scheduling and PUSCH HARQ-ACK timing.

The PDSCH scheduling and PUSCH scheduling may be performed by corresponding PDCCH formats. The systems and methods disclosed herein may be used for UEs that conform to proposed Rel-<NUM> and future LTE specifications. For example, a PDCCH or an enhanced PDCCH (ePDCCH) may be used to schedule PDSCH and/or PUSCH transmissions. The PDSCH HARQ-ACK of CA cells may be reported on a PUCCH or PUSCH of one cell or multiple cells if supported. The PUSCH HARQ-ACK may be signaled on a physical hybrid automatic repeat request (ARQ) indicator channel (PHICH), a PDCCH or an ePDCCH. For UE conforming to the proposed Rel-<NUM> and future LTE specifications, the enhanced PDCCH (ePDCCH) and/or enhanced PHICH (ePHICH) may also be used for PUSCH HARQ-ACK feedback.

In one implementation, a PCell may be a macro cell that may be configured with FDD, and a SCell may be a small cell (e.g., a picocell) that may be configured with TDD. A hybrid duplex CA may include at least one cell (or carrier) with FDD, and at least one cell (or carrier) with TDD. This implementation (e.g., a FDD PCell and a TDD SCell) may be further divided into two cases: self-scheduling and cross-carrier scheduling.

PDSCH scheduling for CA in a hybrid duplexing network may be performed as follows. For PDSCH self-scheduling, the PDSCH transmission on a cell may be indicated by a corresponding PDCCH (or ePDCCH) on the same cell in the same subframe (e.g., the same transmission time interval (TTI)), or for a PDCCH (or ePDCCH) on the same cell in the same subframe indicating a downlink semi-persistent scheduling (SPS) release. Because all PDSCH transmissions may be scheduled on the PDCCH (or ePDCCH) of the same cell in self-scheduling, the same technique may be used for hybrid duplexing networks. In other words, in hybrid duplexing networks, self-scheduling for PDSCH transmission may be performed by a corresponding PDCCH (or ePDCCH) on the same cell in the same subframe.

With cross-carrier scheduling, a PDSCH transmission on a cell may be scheduled by a PDCCH (or an ePDCCH) on another cell. With hybrid duplexing networks, if the scheduling cell is a FDD cell and the scheduled cell is a TDD cell, the PDSCH transmission can always be cross-carrier scheduled by the FDD scheduling cell. In other words, in cross-carrier scheduling, the PDSCH scheduling may follow the scheduling cell timing.

On the other hand, with hybrid duplexing networks, if the scheduling cell is a TDD cell and the scheduled cell is a FDD cell, a PDSCH transmission may be cross-carrier scheduled with some constraints. In one implementation not encompassed by the wording of the claims, the PDSCH transmission on the scheduled cell may be cross-carrier scheduled in the subframes where DL is allocated on the scheduling TDD cell. Therefore, with cross-carrier scheduling, PDSCH scheduling of the scheduled cell may occur in a downlink allocation subframe of the scheduling cell.

In one implementation not encompassed by the wording of the claims, PUSCH scheduling and PUSCH HARQ-ACK may be performed as follows. For PUSCH self-scheduling, the eNB may schedule a PDCCH (or ePDCCH) with a downlink control information (DCI) format <NUM>/<NUM> and/or a PHICH (or ePHICH) transmission on a serving cell in a DL subframe intended for a UE. The UE may adjust the corresponding PUSCH transmission in subframe n+k based on the PDCCH (or ePDCCH) and PHICH (or ePHICH) information, where k may be <NUM> for FDD and k may be decided by the TDD UL-DL configurations of the TDD cells. The PUSCH HARQ-ACK report may be associated with the PUSCH transmission by a PHICH (or ePHICH) or PDCCH (or ePDCCH) on the same cell following the corresponding association timing. Because the PUSCH may be scheduled on the PDCCH (or ePDCCH) of the same cell in self-scheduling, the same techniques may be used for PUSCH scheduling and PUSCH HARQ-ACK reporting in hybrid duplexing networks.

With cross-carrier scheduling, PUSCH scheduling and PUSCH HARQ-ACK reporting may follow a scheduling cell timing. For example, the PUSCH transmission on a cell may be scheduled by an UL grant or PHICH (or ePHICH) feedback from another cell. With hybrid duplexing networks, if the scheduling cell is a FDD cell and the scheduled cell is a TDD cell, the PUSCH transmission may be cross-carrier scheduled.

In one implementation, because UL may be allocated in all subframes of the scheduling FDD cell, the scheduled TDD cell may always be cross-carrier scheduled with the FDD cell timing on PUSCH scheduling and PUSCH HARQ-ACK reporting. For example, a fixed <NUM> millisecond (ms) PUSCH scheduling and the feedback association timing of a FDD cell may be used to cross-carrier schedule a TDD cell.

In another implementation, the PUSCH scheduling and PUSCH HARQ-ACK reporting timing of a TDD cell may be used for the cross-carrier scheduling by a scheduling FDD cell. This approach ensures the same PUSCH scheduling and PUSCH HARQ-ACK timing for both self-scheduling and cross-carrier scheduling cases.

On the other hand, with a hybrid duplexing network in which the scheduling cell is a TDD cell and the scheduled cell is a FDD cell, the PUSCH transmission may be cross-carrier scheduled with some constraints. The scheduled FDD cell may follow the scheduling TDD cell timing on PUSCH scheduling and HARQ-ACK reporting. But the subframes with DL allocation in the TDD scheduling cell may not be able to schedule PUSCH transmission on the scheduled FDD cell. For example, the FDD cell may have a fixed turnaround time of <NUM> for PUSCH scheduling and HARQ-ACK reporting, but all TDD UL-DL configurations have at least <NUM> turnaround time. Therefore, the FDD cell timing cannot be applied for PUSCH scheduling and HARQ-ACK reporting for CA in a hybrid duplexing network with cross-carrier scheduling when the scheduling cell is a TDD cell and the scheduled cell is FDD.

Additionally, for CA in a hybrid duplexing network with more than <NUM> cells, a reference cell for PUSCH cross-carrier scheduling and PUSCH HARQ-ACK reporting may be used. For example, if the PCell is a TDD cell, a FDD cell may be configured as a reference cell for PUSCH cross-carrier scheduling and PUSCH HARQ-ACK reporting.

PDSCH HARQ-ACK reporting for CA in a hybrid duplexing network may be scheduled as follows. The PDSCH HARQ-ACK reporting for FDD and TDD networks are very different. With FDD, the HARQ-ACK for PDSCH transmission in subframe n may be reported in subframe n+<NUM> on a PUCCH or PUSCH transmission. However, with TDD, the PDSCH HARQ-ACK may only be reported on subframes with an UL allocation. Therefore, with TDD, an UL subframe may be associated with more than one DL subframe for PDSCH HARQ-ACK reporting. Accordingly, multi-cell HARQ-ACK reporting for CA in hybrid duplexing networks may be specified.

PDSCH HARQ-ACK reporting for CA in a hybrid duplexing network may include reporting the PDSCH HARQ-ACK information on the PUCCH on one cell only. For example, the PDSCH HARQ-ACK information may be reported on the PUCCH of the PCell. In Rel-<NUM> and Rel-<NUM>, the PUCCH may be reported on the PCell for FDD CA and TDD CA with the same or different TDD UL-DL configurations. The PUCCH may also be reported on the PCell for CA in a hybrid duplexing network.

In one implementation, if the PCell is configured with FDD, the FDD PDSCH association timing may be applied to all TDD cells. For example, a TDD cell may follow the timing of a FDD cell in PDSCH HARQ-ACK reporting for CA in a hybrid duplexing network. Because a DL is available in all subframes on a FDD cell, the PDSCH HARQ-ACK information on a TDD cell may always be reported on a corresponding UL of a FDD cell (e.g., a PCell). Therefore, a TDD cell may be treated as a half-duplex FDD cell that operates on a single frequency carrier instead of separate frequency carriers for the UL and DL. In other words, the downlink subframe associations for the TDD cells may follow the PDSCH association timing of an FDD cell.

This implementation may be applied regardless of the number of TDD cells and the TDD UL-DL configurations of the TDD cells. Furthermore, this implementation may provide flexible TDD UL-DL reconfiguration without changing of association timings. Therefore, this implementation may provide better support for enhanced interference management with traffic adaption (eIMTA).

This approach may provide simple and consistent timing for CA in a hybrid duplexing network that may employ different UL-DL configurations. Furthermore, the PDSCH HARQ-ACK payload may be smaller and more evenly distributed to all UL subframes. With this implementation, CA in a hybrid duplexing network may be treated as a special case of CA in a FDD network.

For a cross-carrier scheduling case where the scheduling cell is configured with FDD and the scheduled cell is configured with TDD, this implementation may allow for the scheduling cell timing to be applied on the scheduled cell. This implementation may also be used for self-scheduling.

Besides the PDSCH HARQ-ACK, the channel state information (CSI) reports of FDD and TDD cells may also be reported on the PUCCH of the PCell only. UCI, including CSI and the PDSCH HARQ-ACK, may also be reported on the PUSCH of an allocated cell with the lowest Cell ID.

In another implementation, not encompassed by the wording of the claims, each cell in a hybrid duplexing network may follow its own timing. In an UL subframe n, the PDSCH HARQ-ACK bits of all cells may be generated based on each cell's own association timings. The PDSCH HARQ-ACK bits of all cells may then be multiplexed and reported on the PUCCH on the PCell. In the case where the PUSCH is scheduled in subframe n, the PDSCH HARQ-ACK bits may be multiplexed on the PUSCH of the cell with the lowest Cell ID.

If a PCell is configured with FDD, a TDD SCell may maintain its own PDSCH association timing. For example, in the case where a PCell is configured with FDD, an UL subframe is available in every subframe. Therefore, in one implementation of CA in a hybrid duplexing network, a TDD cell following its own PDSCH HARQ-ACK timing may always report the PDSCH HARQ-ACK on an UL on the PCell. In other words, when determining a set of downlink subframe associations for the TDD SCell, the TDD SCell may maintain the PDSCH association timing of the TDD SCell.

This implementation may be applied even if the hybrid duplexing network may include multiple TDD cell with the same or different TDD UL-DL configurations. This approach may result in unbalanced PDSCH HARQ-ACK payload in different UL subframes. In a subframe where a TDD cell is allocated with UL, the PUCCH or PUSCH reporting may carry more HARQ-ACK bits than a subframe where the TDD cell is allocated with DL.

For PDSCH transmissions with self-scheduling, this implementation may maintain the PDSCH HARQ-ACK timing of each cell. The PDSCH HARQ-ACK bits may be multiplexed and reported on the PUCCH on the PCell. For cross-carrier scheduling, this implementation may also be applied. In one case, a scheduling cell PDSCH HARQ-ACK timing may be used for PDSCH transmissions with cross-carrier scheduling. In another case, the scheduled cell PDSCH HARQ-ACK timing may be used for PDSCH transmissions with cross-carrier scheduling.

In yet another implementation, not encompassed by the wording of the claims, of PDSCH HARQ-ACK reporting for CA in a hybrid duplexing network, a reporting cell may be used if a PCell is a TDD cell. It should be noted that the macro cell and small cell configuration does not necessarily mean the PCell is the macro cell and SCell is a small cell. In some cases, the PCell may be the small cell and the SCell may be the macro cell. Therefore, though the systems and methods above are discussed mainly for the case where a PCell may be configured with FDD and a SCell may be configured with TDD, in another implementation, the PCell may be configured with TDD and the SCell may be configured with FDD.

FDD timing is simple and consistent, compared with TDD timing, which is different for different TDD UL-DL configurations that may appear in a set of small cells af-filiated with, or spatially relevant with, an area associated with a larger cell. Therefore, it may be better to use a FDD (larger) cell to report the UCI (e.g., PDSCH HARQ-ACK and CSI). Therefore, for CA in a hybrid duplexing network, a FDD cell may be configured as a PDSCH HARQ-ACK reporting cell (also denoted as a reference cell) even if the PCell is a TDD cell. In other words, the PDSCH HARQ-ACK reporting may be on a SCell that is configured with FDD. The PDSCH HARQ-ACK reporting cell or reference cell may be the UCI reporting cell (e.g., the UCI transmission cell) or reference cell so that all UCI is reported on the UCI reporting cell. The UCI may include HARQ-ACK and channel state information (CSI). The CSI may include channel quality indicator (CQI) and/or rank indication (RI) and/or precoding matrix indicator (PMI) and/or precoding type indicator (PTI) etc..

In another implementation, a PDSCH HARQ-ACK reporting cell or UCI reporting cell may be implicitly decided as the FDD cell with the lowest Cell_ID. Additionally, the PDSCH HARQ-ACK reporting cell or UCI reporting cell may be configured by physical (PHY) layer signaling (e.g., in the synchronization, broadcasting signals, system information block (SIB) <NUM> and/or SIB messages). Furthermore, the PDSCH HARQ-ACK reporting cell or UCI reporting cell may be configured by higher layer signaling (e.g., radio resource control (RRC) signaling). Therefore, the PDSCH HARQ-ACK of all cells may be reported on the PUCCH or PUSCH of the configured reporting cell.

In an example not encompassed by the wording of the claims, PDSCH HARQ-ACK reporting for CA in a hybrid duplexing network may also be separate and independent for FDD cells and TDD cells. In other words, cells for each duplex may maintain independent PUCCH and/or PUSCH reports.

TDD and FDD systems have very different PDSCH HARQ-ACK association timings. Also, there are considerable differences on the PDCCH (or ePDCCH) formats and CSI estimation and reports. Therefore, in an implementation, not encompassed by the wording of the claims, of CA in a hybrid duplexing network, the FDD cells and TDD cells may maintain separate and independent PDSCH HARQ-ACK reporting and CSI feedback mechanisms. For example, one FDD cell may be configured as the PCell (or anchor cell) for all FDD cells, and one TDD cell may be configured as the PCell (or anchor cell) for all TDD cells. The FDD cells may perform CA as in Rel-<NUM>/<NUM>, and the TDD cells may perform CA as in Rel-<NUM> if all TDD cells have the same TDD UL-DL configuration or the TDD cells may perform CA as in Rel-<NUM> if different TDD UL-DL configurations are used in the TDD cells. Therefore, if the PCell is a macro cell with FDD and the SCell is a small cell with TDD, the small cell may perform PUCCH reporting that is separate and independent from the macro cell.

In a hybrid duplexing network, the PCell may be a FDD cell or a TDD cell. The FDD PCell and the TDD PCell may be the PCell or a SCell configured to perform CA in a hybrid duplexing network. The FDD PCell may also be configured as a FDD anchor cell. Furthermore, the TDD PCell may also be configured as a TDD anchor cell. The FDD PCell (or FDD anchor cell) or the TDD PCell (or TDD anchor cell) may be the PCell or the secondary PCell.

Therefore, a PUCCH on the FDD PCell may be used to report PDSCH HARQ-ACK for all FDD cells, and a PUCCH on the TDD PCell may be used to report PDSCH HARQ-ACK information for all TDD cells. Therefore, in CA with hybrid duplexing networks, PUCCH reporting on a SCell may be supported, where the given SCell may operate as an anchor cell or secondary PCell.

In a subframe where UCI (e.g., PDSCH HARQ-ACK information and/or CSI) is reported for the FDD cells only, the UCI may be reported on the PUCCH of the FDD PCell. In a subframe where UCI (e.g., PDSCH HARQ-ACK information and/or CSI) is reported for the TDD cells only, the UCI may be reported on the PUCCH of the TDD PCell.

Two implementations may be used to report PDSCH HARQ-ACK bits on both FDD cells and TDD cells in the same subframe. In one implementation, multiple PUCCHs may be reported simultaneously on the FDD PCell (or FDD anchor cell) and the TDD PCell (or TDD anchor cell). In another implementation, only one PUCCH may be reported, and the PDSCH HARQ-ACK bits of both the FDD and TDD cells may be multiplexed and reported on the PUCCH of the PCell only.

With independent reporting for FDD and TDD cells, the PDSCH HARQ-ACK in-formation or CSI may also be reported on a PUSCH. In one implementation, the PDSCH HARQ-ACK information and CSI of all FDD cells may be reported on an allocated PUSCH of the FDD cell with the lowest Cell_ID. The PDSCH HARQ-ACK information and/or CSI of all TDD cells may also be reported on an allocated PUSCH of the TDD cell with the lowest Cell_ID. In another implementation, the PDSCH HARQ-ACK information and/or CSI reporting for FDD cells and the PDSCH HARQ-ACK information and/or CSI reporting for TDD cells may use different channel formats. For example, the PDSCH HARQ-ACK information and CSI of FDD cells may be reported on a PUCCH and the PDSCH HARQ-ACK information and CSI of TDD cells may be reported on a PUSCH, and vice versa. In yet another implementation, the PDSCH HARQ-ACK information and CSI of all FDD and TDD cells may be multiplexed together and reported on the allocated PUSCH of the cell with the lowest Cell ID.

It should be noted that independent reporting (on PUCCH or PUSCH) by FDD and TDD cells may be used if the PCell is configured with either FDD or TDD. Furthermore, it should be noted that independent reporting (on PUCCH or PUSCH) by FDD and TDD cells may be applied to both self-scheduling and cross-carrier scheduling.

The systems and methods disclosed herein may provide the following benefits. CA in a hybrid duplexing network that includes FDD and TDD cells may operate seamlessly. In an example not encompassed by the wording of the claims, resource use may be flexible when both FDD and TDD are used by a UE. HARQ-ACK reporting methods may support the dynamic UL-DL reconfiguration of TDD cells. In another example not encompassed by the wording of the claims, independent uplink control information (UCI) reporting on a PUCCH or a PUSCH may be performed by carriers with different duplexing methods. Standalone operations for carriers with different duplexing methods may be supported. The use of a FDD cell timing on a TDD cell in a hybrid CA scenario is supported. Additionally, in yet another example not encompassed by the wording of the claims, a reporting cell (or reference cell) implementation by physical (PHY) layer signaling, implicit signaling and/or higher layer signaling may be supported.

Various examples of the systems and methods disclosed herein are now described with reference to the Figures, where like reference numbers may indicate functionally similar elements. The systems and methods as generally described and illustrated in the Figures herein could be arranged and designed in a wide variety of different implementations. Thus, the following more detailed description of several implementations, as represented in the Figures, is not intended to limit scope, as claimed, but is merely representative of the systems and methods.

<FIG> is a block diagram illustrating one configuration of one or more eNBs <NUM> and one or more UEs <NUM> in which systems and methods for carrier aggregation may be implemented. The one or more UEs <NUM> communicate with one or more eNBs <NUM> using one or more antennas 122a-n. For example, a UE <NUM> transmits electromagnetic signals to the eNB <NUM> and receives electromagnetic signals from the eNB <NUM> using the one or more antennas 122a-n. The eNB <NUM> communicates with the UE <NUM> using one or more antennas 180a-n.

The UE <NUM> and the eNB <NUM> may use one or more channels <NUM>, <NUM> to communicate with each other. For example, a UE <NUM> may transmit information or data to the eNB <NUM> using one or more uplink channels <NUM>. Examples of uplink channels <NUM> include a PUCCH and a PUSCH, etc. The one or more eNBs <NUM> may also transmit information or data to the one or more UEs <NUM> using one or more downlink channels <NUM>, for instance. Examples of downlink channels <NUM> include a PDCCH, a PDSCH, etc. Other kinds of channels may be used.

Each of the one or more UEs <NUM> may include one or more transceivers <NUM>, one or more demodulators <NUM>, one or more decoders <NUM>, one or more encoders <NUM>, one or more modulators <NUM>, a data buffer <NUM> and a UE operations module <NUM>. For example, one or more reception and/or transmission paths may be implemented in the UE <NUM>. For convenience, only a single transceiver <NUM>, decoder <NUM>, demodulator <NUM>, encoder <NUM> and modulator <NUM> are illustrated in the UE <NUM>, though multiple parallel elements (e.g., transceivers <NUM>, decoders <NUM>, demodulators <NUM>, encoders <NUM> and modulators <NUM>) may be implemented.

The transceiver <NUM> may include one or more receivers <NUM> and one or more transmitters <NUM>. The one or more receivers <NUM> may receive signals from the eNB <NUM> using one or more antennas 122a-n. For example, the receiver <NUM> may receive and downconvert signals to produce one or more received signals <NUM>. The one or more received signals <NUM> may be provided to a demodulator <NUM>. The one or more transmitters <NUM> may transmit signals to the eNB <NUM> using one or more antennas 122a-n. For example, the one or more transmitters <NUM> may upconvert and transmit one or more modulated signals <NUM>.

The demodulator <NUM> may demodulate the one or more received signals <NUM> to produce one or more demodulated signals <NUM>. The one or more demodulated signals <NUM> may be provided to the decoder <NUM>. The UE <NUM> may use the decoder <NUM> to decode signals. The decoder <NUM> may produce one or more decoded signals <NUM>, <NUM>. For example, a first UE-decoded signal <NUM> may comprise received payload data, which may be stored in a data buffer <NUM>. A second UE-decoded signal <NUM> may comprise overhead data and/or control data. For example, the second UE-decoded signal <NUM> may provide data that may be used by the UE operations module <NUM> to perform one or more operations.

As used herein, the term "module" may mean that a particular element or component may be implemented in hardware, software or a combination of hardware and software. However, it should be noted that any element denoted as a "module" herein may alternatively be implemented in hardware. For example, the UE operations module <NUM> may be implemented in hardware, software or a combination of both.

In general, the UE operations module <NUM> may enable the UE <NUM> to communicate with the one or more eNBs <NUM>. The UE operations module <NUM> may include one or more of a UE UCI transmission cell determination module <NUM>, a UE first cell selection module <NUM>, a UE downlink subframe associations determination module <NUM> and a UE PDSCH HARQ-ACK module <NUM>.

The UE UCI transmission cell determination module <NUM> may determine a cell that may transmit UCI information between the UE <NUM> and the eNB <NUM>. Examples of UCI include PDSCH HARQ-ACK information and CSI. The UCI transmission cell may be either a FDD cell or a TDD cell. Therefore, the UE UCI transmission cell determination module <NUM> may determine a UCI transmission cell that is either a FDD or a TDD cell. In one implementation, the UE UCI transmission cell determination module <NUM> may select which cell may be the UCI transmission cell. In another implementation, the UE UCI transmission cell determination module <NUM> may be instructed (by the eNB <NUM>, for example) which cell to use for the UCI transmission. For example, the UE <NUM> may receive an indicator from the eNB <NUM> that indicates one or more cells for UCI transmission. Accordingly, the UE UCI transmission cell determination module <NUM> may determine one or more cells for UCI transmission based on (e.g., indicated by) the indicator. The UCI transmission cell may include a communication channel <NUM>, <NUM> between the UE <NUM> and an eNB <NUM> for transmitting UCI.

In one implementation, the UE UCI transmission cell determination module <NUM> may determine that the UCI transmission cell is a FDD cell. In one example, the UE UCI transmission cell determination module <NUM> may determine that the UCI transmission cell is a PCell configured with FDD. In this example, the UCI may be sent on one cell only (e.g., a PCell) for all of the CA cells (e.g., the FDD cell(s) and TDD cell(s)) in the hybrid duplexing network.

In another implementation, not encompassed by the wording of the claims, the UE UCI transmission cell determination module <NUM> may determine that the UCI transmission cell is a FDD reporting cell. For example, the PCell may be a TDD cell, and the UCI transmission cell may be a reporting cell configured with FDD.

In yet another implementation not encompassed by the wording of the claims, the UE UCI transmission cell determination module <NUM> may determine a UCI transmission cell and a second UCI transmission cell that utilize different duplexing. For example, the UE UCI transmission cell determination module <NUM> may determine a UCI transmission cell for one or more FDD cells, and the UE UCI transmission cell determination module <NUM> may also determine a separate second UCI transmission cell for one or more TDD cells. In this implementation, the UCI transmission cell for the FDD cells may be a FDD anchor cell, and the second UCI transmission cell for the TDD cells may be a TDD anchor cell.

The UE first cell selection module <NUM> may select a cell for FDD and TDD carrier aggregation. In one implementation not encompassed by the wording of the claims, the UE first cell selection module <NUM> may select a TDD cell that may be included with the UCI transmission cell in performing CA. Alternatively, the UE first cell selection module <NUM> may select a FDD cell that may be included with the UCI transmission cell in performing CA. In some implementations, the UE first cell selection module <NUM> may determine the cell for FDD and TDD carrier aggregation based on an indicator (from the eNB <NUM>) that indicates the cell for FDD and TDD carrier aggregation.

The UE downlink subframe associations determination module <NUM> may determine a set of downlink subframe associations for the first cell that indicate at least one UCI transmission uplink subframe of the UCI transmission cell. The set of downlink subframe associations may include timings (e.g., PDSCH HARQ-ACK associations) that correspond to a UCI transmission uplink subframe. In some implementations, the UE downlink subframe associations determination module <NUM> may determine the set of downlink subframe associations based on an indicator (from the eNB <NUM>) that indicates the set of downlink subframe associations.

In one implementation, the UE downlink subframe associations determination module <NUM> may determine that the set of downlink associations for the first cell may include the PDSCH association timing of the UCI transmission cell. For example, if the UCI transmission cell is a FDD cell and the first cell is a TDD cell, the first cell may follow the association timing of a FDD cell.

In another implementation not encompassed by the wording of the claims, the UE downlink subframe associations determination module <NUM> may determine that the set of downlink subframe associations for first cell may include maintaining the PDSCH association timing of the first cell. For example, if the UCI transmission cell is a FDD cell and the first cell is a TDD cell, the first cell may maintain its own PDSCH association timing. Therefore, the first cell may use a TDD UL-DL configuration as described below in connection with <FIG> and <FIG>.

The UE PDSCH HARQ-ACK module <NUM> may send PDSCH HARQ-ACK information in the UCI transmission uplink subframe of the UCI transmission cell. For example, the UE PDSCH HARQ-ACK module <NUM> may send PDSCH HARQ-ACK information in the UCI transmission uplink subframe corresponding to the set of downlink subframe associations. For instance, the UE PDSCH HARQ-ACK module <NUM> may inform the transmitter(s) <NUM> when or when not to send PDSCH HARQ-ACK information based on the set of downlink subframe associations.

In one implementation, the UE PDSCH HARQ-ACK module <NUM> may send PDSCH HARQ-ACK information on the PUCCH or PUSCH of one cell only. For example, the UE PDSCH HARQ-ACK module <NUM> may send PDSCH HARQ-ACK information for all cells (including the first cell) on the PUCCH of a UCI transmission cell that is a FDD cell.

In another implementation not encompassed by the wording of the claims, the UE PDSCH HARQ-ACK module <NUM> may send PDSCH HARQ-ACK information to multiple cells. For example, where the FDD and TDD cells may have separate UCI transmission cells, the UE PDSCH HARQ-ACK module <NUM> may concurrently send PDSCH HARQ-ACK information in a UCI transmission uplink subframe to the UCI transmission cell for the FDD cells and to the second UCI transmission cell for the TDD cells. In other words, PDSCH HARQ-ACK information for the FDD cells may be sent by the UCI transmission cell and the PDSCH HARQ-ACK information for the TDD cells may be sent by the second UCI transmission cell.

The UE operations module <NUM> may provide information <NUM> to the one or more receivers <NUM>. For example, the UE operations module <NUM> may inform the receiver(s) <NUM> when to receive retransmissions.

The UE operations module <NUM> may provide information <NUM> to the demodulator <NUM>. For example, the UE operations module <NUM> may inform the demodulator <NUM> of a modulation pattern anticipated for transmissions from the eNB <NUM>.

The UE operations module <NUM> may provide information <NUM> to the decoder <NUM>. For example, the UE operations module <NUM> may inform the decoder <NUM> of an anticipated encoding for transmissions from the eNB <NUM>.

The UE operations module <NUM> may provide information <NUM> to the encoder <NUM>. The information <NUM> may include data to be encoded and/or instructions for encoding. For example, the UE operations module <NUM> may instruct the encoder <NUM> to encode transmission data <NUM> and/or other information <NUM>. The other information <NUM> may include PDSCH HARQ-ACK information.

The UE operations module <NUM> may provide information <NUM> to the modulator <NUM>. For example, the UE operations module <NUM> may inform the modulator <NUM> of a modulation type (e.g., constellation mapping) to be used for transmissions to the eNB <NUM>. The modulator <NUM> may modulate the encoded data <NUM> to provide one or more modulated signals <NUM> to the one or more transmitters <NUM>.

The UE operations module <NUM> may provide information <NUM> to the one or more transmitters <NUM>. This information <NUM> may include instructions for the one or more transmitters <NUM>. For example, the UE operations module <NUM> may instruct the one or more transmitters <NUM> when to transmit a signal to the eNB <NUM>. In some configurations, this may be based on the UE downlink subframe associations determination module <NUM> (based on a UL-DL configuration, for example). For instance, the one or more transmitters <NUM> may transmit during an UL subframe. The one or more transmitters <NUM> may upconvert and transmit the modulated signal(s) <NUM> to one or more eNBs <NUM>.

The eNB <NUM> may include one or more transceivers <NUM>, one or more demodulators <NUM>, one or more decoders <NUM>, one or more encoders <NUM>, one or more modulators <NUM>, a data buffer <NUM> and an eNB operations module <NUM>. For example, one or more reception and/or transmission paths may be implemented in an eNB <NUM>. For convenience, only a single transceiver <NUM>, decoder <NUM>, demodulator <NUM>, encoder <NUM> and modulator <NUM> are illustrated in the eNB <NUM>, though multiple parallel elements (e.g., transceivers <NUM>, decoders <NUM>, demodulators <NUM>, encoders <NUM> and modulators <NUM>) may be implemented.

The transceiver <NUM> may include one or more receivers <NUM> and one or more transmitters <NUM>. The one or more receivers <NUM> may receive signals from the UE <NUM> using one or more antennas 180a-n. For example, the receiver <NUM> may receive and downconvert signals to produce one or more received signals <NUM>. The one or more received signals <NUM> may be provided to a demodulator <NUM>. The one or more transmitters <NUM> may transmit signals to the UE <NUM> using one or more antennas 180a-n. For example, the one or more transmitters <NUM> may upconvert and transmit one or more modulated signals <NUM>.

The demodulator <NUM> may demodulate the one or more received signals <NUM> to produce one or more demodulated signals <NUM>. The one or more demodulated signals <NUM> may be provided to the decoder <NUM>. The eNB <NUM> may use the decoder <NUM> to decode signals. The decoder <NUM> may produce one or more decoded signals <NUM>, <NUM>. For example, a first eNB-decoded signal <NUM> may comprise received payload data, which may be stored in a data buffer <NUM>. A second eNB-decoded signal <NUM> may comprise overhead data and/or control data. For example, the second eNB-decoded signal <NUM> may provide data (e.g., PDSCH HARQ-ACK information) that may be used by the eNB operations module <NUM> to perform one or more operations.

In general, the eNB operations module <NUM> may enable the eNB <NUM> to communicate with the one or more UEs <NUM>. The eNB operations module <NUM> may include one or more of eNB UCI transmission cell determination module <NUM>, an eNB first cell selection module <NUM>, an eNB downlink subframe associations determination module <NUM> and an eNB PDSCH HARQ-ACK module <NUM>.

The eNB UCI transmission cell determination module <NUM> may determine a cell that may transmit UCI information between the UE <NUM> and the eNB <NUM>. Examples of UCI include PDSCH HARQ-ACK and CSI. The UCI transmission cell may be either a FDD cell or a TDD cell. Therefore, the eNB UCI transmission cell determination module <NUM> may determine a UCI transmission cell that is either a FDD or a TDD cell. In one implementation, the eNB UCI transmission cell determination module <NUM> may select which cell may be the UCI transmission cell. In another implementation, the eNB UCI transmission cell determination module <NUM> may instruct (the UE <NUM>, for example) which cell is the UCI transmission cell. For example, the eNB UCI transmission cell determination module <NUM> may generate and send an indicator that indicates one or more cells for UCI transmission. The UCI transmission cell may include a communication channel <NUM>, <NUM> between the UE <NUM> and an eNB <NUM> for transmitting UCI.

In one implementation, the eNB UCI transmission cell determination module <NUM> may determine that the UCI transmission cell is a FDD cell. Additionally, the eNB UCI transmission cell determination module <NUM> may determine that the UCI transmission cell is a PCell configured with FDD. In this implementation, the UCI may be received on one cell only (e.g., a PCell) for all of the CA cells (e.g., the FDD cells and TDD cells) in the hybrid duplexing network.

In another implementation, the eNB UCI transmission cell determination module <NUM> may determine that the UCI transmission cell is a FDD reporting cell. In an example not encompassed by the wording of the claims, for example, the PCell may be a TDD cell, and the UCI transmission cell may be a reporting cell configured with FDD.

In yet another implementation not encompassed by the wording of the claims, the eNB UCI transmission cell determination module <NUM> may determine a UCI transmission cell and a second UCI transmission cell that utilize different duplexing. For example, the eNB UCI transmission cell determination module <NUM> may determine a UCI transmission cell for one or more FDD cells, and the eNB UCI transmission cell determination module <NUM> may also determine a separate second UCI transmission cell for one or more TDD cells. In this implementation, the UCI transmission cell for the FDD cells may be a FDD anchor cell, and the second UCI transmission cell for the TDD cells may be a TDD anchor cell.

The eNB first cell selection module <NUM> may select a cell for FDD and TDD carrier aggregation. In one implementation, the eNB first cell selection module <NUM> may select a TDD cell that may be included with the UCI transmission cell in performing CA. Alternatively, the eNB first cell selection module <NUM> may select a FDD cell that may be included with the UCI transmission cell in performing CA. In some implementations, the eNB first cell selection module <NUM> may generate and send an indicator (to a UE <NUM>) that indicates the cell for FDD and TDD carrier aggregation.

The eNB downlink subframe associations determination module <NUM> may determine a set of downlink subframe associations for the first cell that indicate at least one UCI transmission uplink subframe of the UCI transmission cell. The set of downlink subframe associations may include timings (e.g., PDSCH HARQ-ACK associations) that correspond to a UCI transmission uplink subframe. In some implementations, the eNB downlink subframe associations determination module <NUM> may generate and send an indicator (to a UE <NUM>) that indicates the set of downlink subframe associations.

In one implementation, the eNB downlink subframe associations determination module <NUM> may determine that the set of downlink associations for the first cell may include the PDSCH association timing of the UCI transmission cell. For example, if the UCI transmission cell is a FDD cell and the first cell is a TDD cell, the first cell may follow the association timing of a FDD cell.

In another implementation not encompassed by the wording of the claims, the eNB downlink subframe associations determination module <NUM> may determine that the set of downlink subframe associations for the first cell may include maintaining the PDSCH association timing of the first cell. For example, if the UCI transmission cell is a FDD cell and the first cell is a TDD cell, the first cell may maintain its own PDSCH association timing. Therefore, the first cell may use a TDD UL-DL configuration as described below in connection with <FIG> and <FIG>.

The eNB PDSCH HARQ-ACK module <NUM> may receive PDSCH HARQ-ACK in-formation in the UCI transmission uplink subframe of the UCI transmission cell. For example, the eNB PDSCH HARQ-ACK module <NUM> may receive PDSCH HARQ-ACK information in the UCI transmission uplink subframe corresponding to the set of downlink subframe associations. For instance, the eNB PDSCH HARQ-ACK module <NUM> may inform the receivers(s) <NUM> when or when not to receive PDSCH HARQ-ACK information based on the set of downlink subframe associations.

In one implementation, the eNB PDSCH HARQ-ACK module <NUM> may receive PDSCH HARQ-ACK information on the PUCCH or PUSCH of one cell only. For example, the eNB PDSCH HARQ-ACK module <NUM> may receive PDSCH HARQ-ACK information for all cells (including the first cell) on the PUCCH of a UCI transmission cell that is a FDD cell.

In another implementation not encompassed by the wording of the claims, the eNB PDSCH HARQ-ACK module <NUM> may receive PDSCH HARQ-ACK information on multiple cells. For example, where the FDD and TDD cells may have separate UCI transmission cells, the eNB PDSCH HARQ-ACK module <NUM> may concurrently receive PDSCH HARQ-ACK information in a UCI transmission uplink subframe on the UCI transmission cell for the FDD cells and/or on the second UCI transmission cell for the TDD cells.

The eNB operations module <NUM> may provide information <NUM> to the one or more receivers <NUM>. For example, the eNB operations module <NUM> may inform the receiver(s) <NUM> when or when not to receive PDSCH HARQ-ACK information based on the set of downlink subframe associations.

The eNB operations module <NUM> may provide information <NUM> to the demodulator <NUM>. For example, the eNB operations module <NUM> may inform the demodulator <NUM> of a modulation pattern anticipated for transmissions from the UE(s) <NUM>.

The eNB operations module <NUM> may provide information <NUM> to the decoder <NUM>. For example, the eNB operations module <NUM> may inform the decoder <NUM> of an anticipated encoding for transmissions from the UE(s) <NUM>.

The eNB operations module <NUM> may provide information <NUM> to the encoder <NUM>. The information <NUM> may include data to be encoded and/or instructions for encoding. For example, the eNB operations module <NUM> may instruct the encoder <NUM> to encode transmission data <NUM> and/or other information <NUM>.

The encoder <NUM> may encode transmission data <NUM> and/or other information <NUM> provided by the eNB operations module <NUM>. For example, encoding the data <NUM> and/ or other information <NUM> may involve error detection and/or correction coding, mapping data to space, time and/or frequency resources for transmission, multiplexing, etc. The encoder <NUM> may provide encoded data <NUM> to the modulator <NUM>. The transmission data <NUM> may include network data to be relayed to the UE <NUM>.

The eNB operations module <NUM> may provide information <NUM> to the modulator <NUM>. This information <NUM> may include instructions for the modulator <NUM>. For example, the eNB operations module <NUM> may inform the modulator <NUM> of a modulation type (e.g., constellation mapping) to be used for transmissions to the UE(s) <NUM>. The modulator <NUM> may modulate the encoded data <NUM> to provide one or more modulated signals <NUM> to the one or more transmitters <NUM>.

The eNB operations module <NUM> may provide information <NUM> to the one or more transmitters <NUM>. This information <NUM> may include instructions for the one or more transmitters <NUM>. For example, the eNB operations module <NUM> may instruct the one or more transmitters <NUM> when to (or when not to) transmit a signal to the UE(s) <NUM>. In some implementations, this may be based on an UL-DL configuration. The one or more transmitters <NUM> may upconvert and transmit the modulated signal(s) <NUM> to one or more UEs <NUM>.

It should be noted that a DL subframe may be transmitted from the eNB <NUM> to one or more UEs <NUM> and that an UL subframe may be transmitted from one or more UEs <NUM> to the eNB <NUM>. Furthermore, both the eNB <NUM> and the one or more UEs <NUM> may transmit data in a standard special subframe.

It should also be noted that one or more of the elements or parts thereof included in the eNB(s) <NUM> and UE(s) <NUM> may be implemented in hardware. For example, one or more of these elements or parts thereof may be implemented as a chip, circuitry or hardware components, etc. It should also be noted that one or more of the functions or methods described herein may be implemented in and/or performed using hardware. For example, one or more of the methods described herein may be implemented in and/or realized using a chipset, an application-specific integrated circuit (ASIC), a large-scale integrated circuit (LSI) or integrated circuit, etc..

<FIG> is a flow diagram illustrating one implementation of a method <NUM> for performing carrier aggregation by a UE <NUM>. A UE <NUM> may determine <NUM> a UCI transmission cell in a wireless communication network with at least one FDD cell and at least one TDD cell. For example, the wireless communication network may be a hybrid duplexing network in which carrier aggregation may be performed with one or more FDD cells and one or more TDD cells. Additionally, in one implementation, the wireless communication network may be an LTE network. UCI may include one or more of PDSCH HARQ-ACK information and CSI. The UCI transmission cell may include a communication channel <NUM>, <NUM> between the UE <NUM> and an eNB <NUM> for transmitting UCI. The UCI transmission cell may be either a FDD cell or a TDD cell. Therefore, the UE <NUM> may determine <NUM> a UCI transmission cell that is either a FDD or a TDD cell. In some implementations, the UE <NUM> may make this determination <NUM> based on an indicator received from an eNB <NUM> that indicates the UCI transmission cell.

In one implementation, the UE may determine <NUM> that the UCI transmission cell is a FDD cell. For example, the UCI transmission cell may be a PCell, which may be a macro cell that is configured with FDD. In this implementation, the UCI may be reported on one cell only (e.g., a PCell) for all of the cells (e.g., the FDD cells and TDD cells) in the hybrid duplexing network. The UCI may be reported on a PUCCH of the PCell. Alternatively, the UCI may be reported on the PUSCH of the allocated cell with the lowest Cell ID.

In another implementation, the UE may determine <NUM> that the UCI transmission cell is a FDD reporting cell. In an example not encompassed by the wording of the claims, the PCell may be a TDD cell, but the UCI transmission cell may be determined <NUM> to be a reporting cell configured with FDD. Therefore, in this implementation, the UCI transmission cell may be a SCell that is configured with FDD.

In yet another implementation not encompassed by the wording of the claims, the UE <NUM> may determine <NUM> a UCI transmission cell for FDD cells, and the UE <NUM> may also determine <NUM> a separate second UCI transmission cell for TDD cells. For example, the FDD cells and TDD cells may maintain independent UCI reports. In this implementation, the UE <NUM> may determine <NUM> that a FDD anchor cell may be the UCI transmission cell for the FDD cells. The FDD anchor cell may be a PCell, SCell or a secondary PCell. The UE <NUM> may also determine <NUM> that a TDD anchor cell may be the second UCI transmission cell for the TDD cells. The TDD anchor cell may be a PCell, SCell or a secondary PCell.

The UE <NUM> may select <NUM> a first cell for FDD and TDD carrier aggregation. For example, the UE <NUM> may select <NUM> a FDD cell or a TDD cell as a first cell for carrier aggregation. The first cell may be a PCell or a SCell. Additionally, the first cell may be the same cell as the UCI transmission cell, or the first cell may be a different cell than the UCI transmission cell. In some implementations, the UE <NUM> may make this selection <NUM> based on an indicator received from an eNB <NUM> that indicates the first cell for FDD and TDD carrier aggregation.

The UE <NUM> may determine <NUM> a set of downlink subframe associations for the first cell that indicate at least one UCI transmission uplink subframe of the UCI transmission cell. The set of downlink subframe associations may include timings (e.g., PDSCH HARQ-ACK associations) for at least one corresponding UCI transmission uplink subframe, as described below in connection with <FIG>, <FIG> and <FIG>. In some implementations, the UE <NUM> may make this determination <NUM> based on an indicator received from an eNB <NUM> that indicates the set of downlink subframe associations.

In one implementation, the UE <NUM> may determine <NUM> that the set of downlink associations for the first cell may include the PDSCH association timing of the UCI transmission cell. For example, if the UCI transmission cell is a FDD cell and the first cell is a TDD cell, the first cell may follow the association timing of a FDD cell. In other words, if the first cell is a TDD cell, the first cell may follow the association timing of a FDD cell in PDSCH HARQ-ACK reporting for CA in a hybrid duplexing network.

In another implementation not encompassed by the wording of the claims, the UE <NUM> may determine <NUM> that the set of downlink subframe associations for first cell may include maintaining a PDSCH association timing of the first cell. For example, if the UCI transmission cell is a FDD cell and the first cell is a TDD cell, the first cell may maintain its own PDSCH association timing. For instance, the first cell may use a TDD UL-DL configuration as described below in connection with <FIG> and <FIG>.

In this implementation, the PDSCH HARQ-ACK bits of the first cell may be multiplexed and reported on the PUCCH or PUSCH on the UCI transmission cell. Alternatively, the FDD cells and the TDD cells may maintain independent reporting mechanisms with their own PDSCH association timings.

The UE <NUM> may send <NUM> PDSCH HARQ-ACK information in the UCI transmission uplink subframe of the UCI transmission cell. For example, the UE <NUM> may send <NUM> PDSCH HARQ-ACK information in the UCI transmission uplink subframe corresponding to the determined <NUM> set of downlink subframe associations.

In one implementation, the UE <NUM> may send <NUM> PDSCH HARQ-ACK information on the PUCCH or PUSCH of one cell only. For example, if the UCI transmission cell is a FDD cell, the first cell is a TDD, and the set of downlink subframe associations for the first cell includes the PDSCH association timing of the UCI transmission cell, the UE <NUM> may send <NUM> PDSCH HARQ-ACK information for the TDD cell in an UL (e.g., PUCCH or PUSCH) of the FDD cell. Because a DL is available in all subframes on a FDD cell, the PDSCH HARQ-ACK on a TDD cell may always be reported on a corresponding UL of a FDD cell.

In another implementation, not encompassed by the wording of the claims, where the UCI transmission cell is a FDD cell, the first cell is a TDD, but the set of downlink subframe associations for the first cell may include maintaining the PDSCH association timing of the first cell, the UE <NUM> may also send <NUM> PDSCH HARQ-ACK information on the PUCCH or PUSCH of one cell only. In this implementation, the PDSCH HARQ-ACK information for each cell may be generated based on its own association timings. For example, a TDD cell may follow a TDD DL-UL configuration as described in connection with <FIG>, and a FDD cell may follow an association timing as described in connection with <FIG>. Therefore, PDSCH HARQ-ACK information for the first cell may be generated according to the association timing of the first cell. Additionally, the PDSCH HARQ-ACK information for the first cell may be multiplexed and sent <NUM> by the UE <NUM> in the UCI transmission uplink subframe of the UCI transmission cell. In other words, the UE <NUM> may send <NUM> PDSCH HARQ-ACK information for the TDD cell in an UL (e.g., PUCCH or PUSCH) of the FDD cell.

In yet another implementation not encompassed by the wording of the claims, where the FDD cells may have a UCI transmission cell and the TDD cells may have a second UCI transmission cell, the UE <NUM> may send <NUM> PDSCH HARQ-ACK information in a UCI transmission uplink subframe to one or more cells. For example, as described above, the FDD cells and TDD cells may maintain independent UCI reports. In this case, the FDD cells may include a UCI transmission cell (e.g., a FDD anchor cell) and the TDD cells may include a second UCI transmission cell (e.g., a TDD anchor cell). Multiple PUCCHs or PUSCHs may be reported concurrently on the FDD anchor cell and the TDD anchor cell. The UE <NUM> may concurrently send <NUM> PDSCH HARQ-ACK information for the FDD cells and TDD cells in a UCI transmission uplink subframe corresponding to the UCI transmission cell or the second UCI transmission cell. Alternatively, the PDSCH HARQ-ACK information for both the FDD cells and the TDD cells may be multiplexed and sent <NUM> in an UL (e.g., PUCCH or PUSCH) of one cell (e.g., a PCell).

<FIG> is a flow diagram illustrating one implementation of a method <NUM> for performing carrier aggregation by an eNB <NUM>. An eNB <NUM> may determine <NUM> a UCI transmission cell in a wireless communication network with at least one FDD cell and at least one TDD cell. For example, the wireless communication network may be a hybrid duplexing network in which carrier aggregation may be performed with one or more FDD cell and one or more TDD cell. Additionally, in one implementation, the wireless communication network may be an LTE network. UCI may include one or more of PDSCH HARQ-ACK information and CSI. The UCI transmission cell may include a communication channel <NUM>, <NUM> between the eNB <NUM> and a UE <NUM> for transmitting UCI. The UCI transmission cell may be either a FDD cell or a TDD cell. Therefore, the eNB <NUM> may determine <NUM> a UCI transmission cell that is either a FDD or a TDD cell. In some implementations, the eNB <NUM> may generate and send an indicator based on this determination <NUM> that indicates the UCI transmission cell.

In another implementation, the UE may determine <NUM> that the UCI transmission cell is a FDD reporting cell. In an example not encompassed by the wording of the claims, the PCell may be a TDD cell, but the UCI transmission cell may be determined <NUM> to be a reporting cell configured with FDD. Therefore, in this implementation, the UCI transmission cell may be an SCell that is configured with FDD.

In yet another implementation not encompassed by the wording of the claims, the eNB <NUM> may determine <NUM> a UCI transmission cell for FDD cells, and the eNB <NUM> may also determine <NUM> a separate second UCI transmission cell for TDD cells. For example, the FDD cells and TDD cells may maintain independent UCI reports. In this implementation, the eNB <NUM> may determine <NUM> that a FDD anchor cell may be the UCI transmission cell for the FDD cells. The FDD anchor cell may be a PCell, SCell or a secondary PCell. The eNB <NUM> may also determine <NUM> that a TDD anchor cell may be the second UCI transmission cell for the TDD cells. The TDD anchor cell may be a PCell, SCell or a secondary PCell.

The eNB <NUM> may select <NUM> a first cell for FDD and TDD carrier aggregation. For example, the eNB <NUM> may select <NUM> a FDD cell or a TDD cell as a first cell for carrier aggregation. The first cell may be a PCell or an SCell. In some implementations, the eNB <NUM> may generate and send an indicator based on this selection <NUM> that indicates the first cell for FDD and TDD carrier aggregation.

The eNB <NUM> may determine <NUM> a set of downlink subframe associations for the first cell that indicate at least one UCI transmission uplink subframe of the UCI transmission cell. The set of downlink subframe associations may include timings (e.g., association timings) for at least one corresponding UCI transmission uplink subframe, as described below in connection with <FIG>, <FIG> and <FIG>. In some implementations, the eNB <NUM> may generate and send an indicator based on this determination <NUM> that indicates the set of downlink subframe associations.

In one implementation, the eNB <NUM> may determine <NUM> that the set of downlink associations for the first cell may include the PDSCH association timing of a UCI transmission cell. For example, if the UCI transmission cell is a FDD cell and the first cell is a TDD cell, the first cell may follow the association timing of a FDD cell. In other words, if the first cell is a TDD cell, the first cell may follow the association timing of a FDD cell in PDSCH HARQ-ACK reporting for CA in a hybrid duplexing network.

In another implementation not encompassed by the wording of the claims, the eNB <NUM> may determine <NUM> that the set of downlink subframe associations for first cell may include maintaining a PDSCH association timing of the first cell. For example, if the UCI transmission cell is a FDD cell and the first cell is a TDD cell, the first cell may maintain its own PDSCH association timing. For instance, the first cell may use a TDD UL-DL configuration as described below in connection with <FIG> and <FIG>.

In this implementation, the PDSCH HARQ-ACK Bits of the first cell may be multiplexed and reported on the PUCCH or PUSCH on the UCI transmission cell. Alternatively, the FDD cells and the TDD cells may maintain independent reporting mechanisms with their own PDSCH association timings.

The eNB <NUM> may receive <NUM> PDSCH HARQ-ACK information in the UCI transmission uplink subframe of the UCI transmission cell. For example, the eNB <NUM> may receive <NUM> PDSCH HARQ-ACK information in the UCI transmission uplink subframe corresponding to the determined <NUM> set of downlink subframe associations.

In one implementation, the eNB <NUM> may receive <NUM> PDSCH HARQ-ACK information on the PUCCH or PUSCH of one cell only. For example, if the UCI transmission cell is a FDD cell, the first cell is a TDD, and the set of downlink subframe associations for the first cell includes the PDSCH association timing of the UCI transmission cell, the eNB <NUM> may receive <NUM> PDSCH HARQ-ACK information for the TDD cell in an UL (e.g., PUCCH or PUSCH) of the FDD cell. Because a DL is available in all subframes on a FDD cell, the PDSCH HARQ-ACK on a TDD cell may always be reported on a corresponding UL of a FDD cell.

In another implementation not encompassed by the wording of the claims where the UCI transmission cell is a FDD cell, the first cell is a TDD, but the set of downlink subframe associations for the first cell may include maintaining the PDSCH association timing of the first cell, the eNB <NUM> may also receive <NUM> PDSCH HARQ-ACK information on the PUCCH or PUSCH of one cell only. In this implementation, the PDSCH HARQ-ACK information for each cell may be generated based on its own association timings. For example, a TDD cell may follow a TDD DL-UL configuration as described in connection with <FIG>, and a FDD cell may follow an association timing as described in connection with <FIG>. Therefore, PDSCH HARQ-ACK information for the first cell may be generated according to the association timing of the first cell. Additionally, the PDSCH HARQ-ACK information for the first cell may be multiplexed and received <NUM> by the eNB <NUM> in the UCI transmission uplink subframe of the UCI transmission cell. In other words, the eNB <NUM> may receive <NUM> PDSCH HARQ-ACK information for the TDD cell in an UL (e.g., PUCCH or PUSCH) of the FDD cell.

In yet another implementation not encompassed by the wording of the claims, where the FDD cells may have a UCI transmission cell and the TDD cells may have a second UCI transmission cell, the eNB <NUM> may receive <NUM> PDSCH HARQ-ACK information in a UCI transmission uplink subframe from one or more cells. For example, as described above, the FDD cells and TDD cells may maintain independent UCI reports. In this case, the FDD cells may include a UCI transmission cell (e.g., a FDD anchor cell) and the TDD cells may include a second UCI transmission cell (e.g., a TDD anchor cell). Multiple PUCCHs or PUSCHs may be reported concurrently on the FDD anchor cell and the TDD anchor cell. The eNB <NUM> may concurrently receive <NUM> PDSCH HARQ-ACK information for the FDD cells and TDD cells in a UCI transmission uplink subframe corresponding to the UCI transmission cell or the second UCI transmission cell. Alternatively, the PDSCH HARQ-ACK information for both the FDD cells and the TDD cells may be multiplexed and received <NUM> in an UL (e.g., PUCCH or PUSCH) of one cell (e.g., a PCell).

<FIG> is a diagram illustrating one example of a radio frame <NUM> that may be used in accordance with the systems and methods disclosed herein. This radio frame <NUM> structure illustrates a TDD structure. Each radio frame <NUM> may have a length of <MAT> ms, where.

TDD UL-DL configurations <NUM>-<NUM> are given below in Table (<NUM>) (from Table <NUM>-<NUM> in 3GPP TS <NUM>). UL-DL configurations with both <NUM> millisecond (ms) and <NUM> downlink-to-uplink switch-point periodicity may be supported. In particular, seven UL-DL configurations are specified in 3GPP specifications, as shown in Table (<NUM>) below. In Table (<NUM>), "D" denotes a downlink subframe, "S" denotes a special subframe and "U" denotes an UL subframe.

In Table (<NUM>) above, for each subframe in a radio frame, "D" indicates that the subframe is reserved for downlink transmissions, "U" indicates that the subframe is reserved for uplink transmissions and "S" indicates a special subframe with three fields: a downlink pilot time slot (DwPTS), a guard period (GP) and an uplink pilot time slot (UpPTS). The length of DwPTS and UpPTS is given in Table (<NUM>) (from Table <NUM>-<NUM> of 3GPP TS <NUM>) subject to the total length of DwPTS, GP and UpPTS being equal to <MAT> ms. In Table (<NUM>), "cyclic prefix" is abbreviated as "CP" and "configuration" is abbreviated as "Config" for convenience.

UL-DL configurations with both <NUM> and <NUM> downlink-to-uplink switch-point periodicity are supported. In the case of <NUM> downlink-to-uplink switch-point periodicity, the special subframe exists in both half-frames. In the case of <NUM> downlink-to-uplink switch-point periodicity, the special subframe exists in the first half-frame only. Subframes <NUM> and <NUM> and DwPTS may be reserved for downlink transmission. UpPTS and the subframe immediately following the special subframe may be reserved for uplink transmission.

In accordance with the systems and methods disclosed herein, some types of subframes <NUM> that may be used include a downlink subframe, an uplink subframe and a special subframe <NUM>. In the example illustrated in <FIG>, which has a <NUM> periodicity, two standard special subframes 431a-b are included in the radio frame <NUM>.

The first special subframe 431a includes a downlink pilot time slot (DwPTS) 425a, a guard period (GP) 427a and an uplink pilot time slot (UpPTS) 429a. In this example, the first standard special subframe 431a is included in subframe one 423b. The second standard special subframe 431b includes a downlink pilot time slot (DwPTS) 425b, a guard period (GP) 427b and an uplink pilot time slot (UpPTS) 429b. In this example, the second standard special subframe 431b is included in subframe six <NUM>. The length of the DwPTS 425a-b and UpPTS 429a-b may be given by Table <NUM>-<NUM> of 3GPP TS <NUM> (illustrated in Table (<NUM>) above) subject to the total length of each set of DwPTS <NUM>, GP <NUM> and UpPTS <NUM> being equal to <MAT> ms.

Each subframe i 423a-j (where i denotes a subframe ranging from subframe zero 423a (e.g., <NUM>) to subframe nine 423j (e.g., <NUM>) in this example) is defined as two slots, 2i and 2i+<NUM> of length <MAT> ms in each subframe <NUM>. For example, subframe zero (e.g., <NUM>) 423a may include two slots, including a first slot.

UL-DL configurations with both <NUM> and <NUM> downlink-to-uplink switch-point periodicity may be used in accordance with the systems and methods disclosed herein. <FIG> illustrates one example of a radio frame <NUM> with <NUM> switch-point periodicity. In the case of <NUM> downlink-to-uplink switch-point periodicity, each half-frame <NUM> includes a standard special subframe 431a-b. In the case of <NUM> downlink-to-uplink switch-point periodicity, a special subframe may exist in the first half-frame <NUM> only.

Subframe zero (e.g., <NUM>) 423a and subframe five (e.g., <NUM>) 423f and DwPTS 425a-b may be reserved for downlink transmission. The UpPTS 429a-b and the subframe(s) immediately following the special subframe(s) 431a-b (e.g., subframe two 423c and subframe seven <NUM>) may be reserved for uplink transmission. It should be noted that, in some implementations, special subframes <NUM> may be considered DL subframes in order to determine a set of DL subframe associations that indicate UCI transmission uplink subframes of a UCI transmission cell.

<FIG> is a diagram illustrating some TDD UL-DL configurations 537a-g in accordance with the systems and methods described herein. In particular, <FIG> illustrates UL-DL configuration zero 537a (e.g., "UL-DL configuration <NUM>") with subframes 523a and subframe numbers 539a, UL-DL configuration one 537b (e.g., "UL-DL configuration <NUM>") with subframes 523b and subframe numbers 539b, UL-DL configuration two 537c (e.g., "UL-DL configuration <NUM>") with subframes 523c and subframe numbers 539c and UL-DL configuration three 537d (e.g., "UL-DL configuration <NUM>") with subframes 523d and subframe numbers 539d. <FIG> also illustrates UL-DL configuration four 537e (e.g., "UL-DL configuration <NUM>") with subframes 523e and subframe numbers 539e, UL-DL configuration five 537f (e.g., "UL-DL configuration <NUM>") with subframes 523f and subframe numbers 539f and UL-DL configuration six <NUM> (e.g., "UL-DL configuration <NUM>") with subframes <NUM> and subframe numbers <NUM>.

<FIG> further illustrates PDSCH HARQ-ACK associations <NUM> (e.g., PDSCH HARQ-ACK feedback on PUCCH or PUSCH associations). The PDSCH HARQ-ACK associations <NUM> may indicate HARQ-ACK reporting subframes corresponding to subframes for PDSCH transmissions (e.g., subframes in which PDSCH transmissions may be sent and/or received). It should be noted that some of the radio frames illustrated in <FIG> have been truncated for convenience.

The systems and methods disclosed herein but not encompassed by the wording of the claims may be applied to one or more of the UL-DL configurations 537a-g illustrated in <FIG>. For example, one or more PDSCH HARQ-ACK associations <NUM> corresponding to one of the UL-DL configurations 537a-g illustrated in <FIG> may be applied to communications between a UE <NUM> and eNB <NUM>. For example, an UL-DL configuration <NUM> may be determined (e.g., assigned to, applied to) a PCell. In this case, PDSCH HARQ-ACK associations <NUM> may specify PDSCH HARQ-ACK timing (e.g., a HARQ-ACK reporting subframe) for HARQ-ACK feedback transmissions corresponding to the PCell. For SCell HARQ-ACK feedback transmissions, the PDSCH HARQ-ACK associations <NUM> corresponding to a reference UL-DL configuration in accordance with the feedback parameters may be utilized.

A PDSCH HARQ-ACK association <NUM> may specify a particular (PDSCH HARQ-ACK) timing for receiving HARQ-ACK information corresponding to a PDSCH. A PDSCH HARQ-ACK association <NUM> may specify a reporting subframe in which the UE <NUM> reports (e.g., transmits) the HARQ-ACK information corresponding to the PDSCH to the eNB <NUM>. The reporting subframe may be determined based on the subframe that includes the PDSCH sent by the eNB <NUM>.

<FIG> illustrates a specific implementation, not encompassed by the wording of the claims, of association timings of a TDD cell with UL-DL configuration one <NUM>. <FIG> illustrates UL-DL configuration one <NUM> (e.g., "UL-DL configuration <NUM>") with subframes <NUM> and subframe numbers <NUM>. The PDSCH HARQ-ACK associations <NUM>, PUSCH scheduling <NUM> and PUSCH HARQ-ACK associations <NUM> are illustrated. The PDSCH HARQ-ACK associations <NUM> may indicate HARQ-ACK reporting subframes corresponding to subframes for PDSCH transmissions (e.g., subframes in which PDSCH transmissions may be sent and/or received). In one implementation, the PDSCH HARQ-ACK reporting may occur on a PUCCH or a PUSCH. The PUSCH HARQ-ACK associations <NUM> may indicate HARQ-ACK reporting subframes corresponding to subframes for PUSCH transmissions (e.g., subframes in which PUSCH transmissions may be sent and/or received). In another implementation, the PUSCH HARQ-ACK reporting may occur on a PHICH or a PDCCH. In yet another implementation, the PUSCH scheduling <NUM> may include scheduling by an UL grant or PHICH (or ePHICH) feedback from another cell.

As described above in connection with <FIG>, there are seven different TDD UL-DL configurations 537a-g, all with different association timings. Furthermore, with inter-band TDD CA with different TDD UL-DL configurations, the association timing of one TDD cell may follow the timing of a reference TDD UL-DL configuration. Moreover, in TDD CA with different UL-DL configurations, the PDSCH HARQ-ACK timing may follow one reference TDD UL-DL configuration, and the PUSCH scheduling and HARQ-ACK timing may follow another reference TDD UL-DL configuration. The reference configurations may be the same or different.

<FIG> illustrates the association timings of a FDD cell. The FDD cell may include paired downlink subframes <NUM> and uplink subframes <NUM>. The PDSCH HARQ-ACK associations <NUM>, PUSCH scheduling <NUM> and PUSCH HARQ-ACK associations <NUM> are illustrated. The PDSCH HARQ-ACK associations <NUM> may indicate HARQ-ACK reporting subframes corresponding to subframes for PDSCH transmissions (e.g., subframes in which PDSCH transmissions may be sent and/or received). In some implementations, the PDSCH HARQ-ACK reporting may occur on a PUCCH or a PUSCH. The PUSCH HARQ-ACK associations <NUM> may indicate HARQ-ACK reporting subframes corresponding to subframes for PUSCH transmissions (e.g., subframes in which PUSCH transmissions may be sent and/or received). In some implementations, the PUSCH HARQ-ACK reporting may occur on a PHICH or a PDCCH. In some implementations, the PUSCH scheduling <NUM> may include scheduling by an UL grant or PHICH (or ePHICH) feedback from another cell.

A fixed <NUM> interval may be applied to the PDSCH HARQ-ACK associations <NUM>, PUSCH scheduling <NUM> and PUSCH HARQ-ACK associations <NUM>. For example, each of the downlink subframes <NUM> and uplink subframes <NUM> may be <NUM>. Therefore, the PDSCH HARQ-ACK transmission in subframe m+<NUM> may be associated with a PDSCH transmission in subframe m. A PUSCH transmission in subframe n may be associated with the PUSCH scheduling <NUM> in subframe n-<NUM>. Furthermore, the PUSCH HARQ-ACK transmission in subframe n+<NUM> may be associated with the PUSCH transmission in subframe n. For an FDD cell, for example, a fixed <NUM> may be applied to both PDSCH and PUSCH timings.

<FIG> is a flow diagram illustrating a more specific implementation of a method <NUM> for performing carrier aggregation by a UE <NUM>. This may be accomplished as described above in connection with <FIG>, for example. A UE <NUM> may determine <NUM> a UCI transmission cell in a wireless communication network with at least one FDD cell and at least one TDD cell. For example, the wireless communication network may be a hybrid duplexing network in which carrier aggregation may be performed with one or more FDD cell and one or more TDD cell. The UCI transmission cell may be either a FDD cell or a TDD cell.

In one implementation, the UE <NUM> may determine <NUM> a UCI transmission cell is a FDD cell or a TDD cell. This may be accomplished as described above in connection with <FIG>. For example, the UCI transmission cell may be a PCell, which may be a macro cell that is configured with FDD. In this implementation, the UCI may be reported on one cell only (e.g., a PCell) for all of the cells (e.g., the FDD cells and TDD cells) in the hybrid duplexing network. For instance, the UCI may be reported on a PUCCH of the PCell.

The UE <NUM> may select <NUM> a first cell for FDD and TDD carrier aggregation. This may be accomplished as described above in connection with <FIG>, for instance. For example, the UE <NUM> may select <NUM> a TDD cell as a first cell for carrier aggregation.

The UE <NUM> may determine <NUM> a PDSCH scheduling for the first cell. For example, with PDSCH self-scheduling, the PDSCH transmission for the first cell may be indicated by a corresponding PDCCH (or ePDCCH) on the first cell in the same subframe (e.g., the same transmission time interval (TTI)), or for a PDCCH (or ePDCCH) on the first cell in the same subframe indicating a downlink semi-persistent scheduling (SPS) release.

With cross-carrier scheduling, the PDSCH transmission on the first cell may be scheduled by the PDCCH (or ePDCCH) on another cell. For example, if the scheduling cell is a FDD cell (e.g., a PCell) and the first cell is a TDD cell, the PDSCH scheduling may follow the scheduling cell timing. On the other hand, if the scheduling cell is a TDD cell and the first cell is a FDD cell, a PDSCH transmission may be cross-carrier scheduled, for example, in the subframes where DL is allocated on the scheduling TDD cell.

In an implementation not encompassed by the wording of the claims, the UE <NUM> may determine <NUM> a PUSCH scheduling <NUM>, <NUM> and PUSCH HARQ-ACK associations <NUM>, <NUM> for the first cell. For example, for PUSCH self-scheduling, the eNB <NUM> may schedule a PDCCH (or ePDCCH) with a downlink control in-formation (DCI) format <NUM>/<NUM> and/or a PHICH (or ePHICH) transmission on the first cell in a DL subframe intended for the UE <NUM>. The UE <NUM> may adjust the corresponding PUSCH transmission in subframe n+k based on the PDCCH (or ePDCCH) and PHICH (or ePHICH) information, where k may be <NUM> for FDD, and k may be decided by (e.g., based on) the TDD UL-DL configurations of the TDD cells according to Table <NUM>-<NUM> in 3GPP TS36. The PUSCH HARQ-ACK report may be associated with the PUSCH transmission by a PHICH (or ePHICH) or PDCCH (or ePDCCH) on the first cell following the corresponding PUSCH HARQ-ACK associations <NUM>, <NUM>.

With cross-carrier scheduling, the PUSCH scheduling <NUM>, <NUM> and PUSCH HARQ-ACK associations <NUM>, <NUM> for the first cell may be determined <NUM> based on a scheduling cell timing. For example, the PUSCH transmission on a cell may be scheduled by an UL grant or PHICH (or ePHICH) feedback from another cell (e.g., a scheduling cell). With hybrid duplexing networks, if the scheduling cell is a FDD cell and scheduled cell is a TDD cell, the PUSCH transmission may be cross-carrier scheduled.

In one implementation, because UL may be allocated in all subframes of the scheduling FDD cell, the scheduled TDD cell may always be cross-carrier scheduled with the FDD cell PUSCH scheduling <NUM> and PUSCH HARQ-ACK associations <NUM>. For example, a fixed <NUM> PUSCH scheduling <NUM> and the PUSCH HARQ-ACK associations <NUM> of a FDD cell (as illustrated in connection with <FIG>) may be used to cross-carrier schedule a TDD cell.

On the other hand, if the scheduling cell is a TDD cell and the first cell (e.g., the scheduled cell) is a FDD cell, the first cell may follow the scheduling cell timing on PUSCH scheduling <NUM> and PUSCH HARQ-ACK associations <NUM>. But the subframes with DL allocation in the TDD scheduling cell may not be able to schedule PUSCH transmission on the scheduled FDD cell. For example, if the first cell is a FDD cell, the first cell may have a fixed turnaround time of <NUM> for PUSCH scheduling <NUM> and PUSCH HARQ-ACK associations <NUM>. However, the TDD UL-DL configurations 537a-g have at least <NUM> turnaround time. Therefore, the FDD cell timing (e.g., PUSCH scheduling <NUM> and PUSCH HARQ-ACK associations <NUM>) may not be applied for PUSCH scheduling and PUSCH HARQ-ACK associations for cross-carrier scheduling when the scheduling cell is a TDD cell and the scheduled cell (e.g., the first cell) is a FDD cell.

Additionally, the first cell may be a reference cell for cross-carrier PUSCH scheduling <NUM>, <NUM> and PUSCH HARQ-ACK associations <NUM>, <NUM>. For example, if the PCell is a TDD cell, and the first cell is a FDD cell, the first cell may be configured as a reference cell for cross-carrier PUSCH scheduling <NUM> and PUSCH HARQ-ACK associations <NUM>.

The UE <NUM> may determine <NUM> a set of downlink subframe associations for the first cell that indicate at least one UCI transmission uplink subframe of the UCI transmission cell. This may be accomplished as described above in connection with <FIG>, for example. The set of downlink subframe associations may include timings (e.g., PDSCH HARQ-ACK associations <NUM>, <NUM>) for at least one corresponding UCI transmission uplink subframe. This may be accomplished as described above in connection with <FIG>. For example, the UE <NUM> may determine <NUM> that the set of downlink associations for the first cell may include the PDSCH HARQ-ACK associations <NUM>, <NUM> of a UCI transmission cell. If the UCI transmission cell is a FDD cell and the first cell is a TDD cell, the first cell may follow the PDSCH HARQ-ACK associations <NUM> of the UCI transmission cell configured with FDD.

The UE <NUM> may send <NUM> PDSCH HARQ-ACK information in the UCI transmission uplink subframe of the UCI transmission cell. This may be accomplished as described above in connection with <FIG>, for instance. For example, if the UCI transmission cell is a FDD cell, the first cell is a TDD, and the set of downlink subframe associations for the first cell includes the PDSCH association timing of the UCI transmission cell, the UE <NUM> may send <NUM> PDSCH HARQ-ACK information for the TDD cell in an UL (e.g., PUCCH or PUSCH) of the FDD cell.

<FIG> is a flow diagram illustrating a more specific implementation of a method <NUM> for performing carrier aggregation by an eNB <NUM>. An eNB <NUM> may determine <NUM> a UCI transmission cell in a wireless communication network with at least one FDD cell and at least one TDD cell. This may be accomplished as described above in connection with <FIG>, for instance. For example, the wireless communication network may be a hybrid duplexing network in which carrier aggregation may be performed with one or more FDD cell and one or more TDD cell. The UCI transmission cell may be either a FDD cell or a TDD cell.

In one implementation, the eNB <NUM> may determine <NUM> a UCI transmission cell is a FDD cell or a TDD cell. This may be accomplished as described above in connection with <FIG>. For example, the UCI transmission cell may be a PCell, which may be a macro cell that is configured with FDD. In this implementation, the UCI may be reported on one cell only (e.g., a PCell) for all of the cells (e.g., the FDD cells and TDD cells) in the hybrid duplexing network. For instance, the UCI may be reported on a PUCCH of the PCell.

The eNB <NUM> may select <NUM> a first cell for FDD and TDD carrier aggregation. This may be accomplished as described above in connection with <FIG>, for instance. For example, the eNB <NUM> may select <NUM> a TDD cell as a first cell for carrier aggregation.

The eNB <NUM> may determine <NUM> a PDSCH scheduling for the first cell. For example, with PDSCH self-scheduling, the PDSCH transmission for the first cell may be indicated by a corresponding PDCCH (or ePDCCH) on the first cell in the same subframe (e.g., the same transmission time interval (TTI)), or for a PDCCH (or ePDCCH) on the first cell in the same subframe indicating a downlink semi-persistent scheduling (SPS) release.

With cross-carrier scheduling, the PDSCH transmission on the first cell may be scheduled by the PDCCH (or ePDCCH) on another cell. For example, if the scheduling cell is a FDD cell (e.g., a PCell) and the scheduled cell is a TDD cell, the PDSCH scheduling may follow the scheduling cell timing. On the other hand, if the scheduling cell is a TDD cell and the scheduled cell is a FDD cell, a PDSCH transmission may be cross-carrier scheduled, for example, in the subframes where DL is allocated on the scheduling TDD cell.

In an implementation not encompassed by the wording of the claims, the eNB <NUM> may determine <NUM> a PUSCH scheduling <NUM>, <NUM> and PUSCH HARQ-ACK associations <NUM>, <NUM> for the first cell. For example, for PUSCH self-scheduling, the eNB <NUM> may schedule a PDCCH (or ePDCCH) with a downlink control information (DCI) format <NUM>/<NUM> and/or a PHICH (or ePHICH) transmission on the first cell in a DL subframe intended for the UE <NUM>. The UE <NUM> may adjust the corresponding PUSCH transmission in subframe n+k based on the PDCCH (or ePDCCH) and PHICH (or ePHICH) information, where k may be <NUM> for FDD and k may be decided by the TDD UL-DL configurations of the TDD cells according to Table <NUM>-<NUM> in 3GPP TS36. The PUSCH HARQ-ACK report may be associated with the PUSCH transmission by a PHICH (or ePHICH) or PDCCH (or ePDCCH) on the first cell following the corresponding PUSCH HARQ-ACK associations <NUM>, <NUM>.

The eNB <NUM> may determine <NUM> a set of downlink subframe associations for the first cell that indicate at least one UCI transmission uplink subframe of the UCI transmission cell. The set of downlink subframe associations may include timings (e.g., PDSCH HARQ-ACK associations <NUM>, <NUM>) for at least one corresponding UCI transmission uplink subframe. This may be accomplished as described above in connection with <FIG>, for instance. For example, the eNB <NUM> may determine <NUM> that the set of downlink associations for the first cell may include the PDSCH HARQ-ACK associations <NUM>, <NUM> of a UCI transmission cell. If the UCI transmission cell is a FDD cell and the first cell is a TDD cell, the first cell may follow the PDSCH HARQ-ACK associations <NUM> of the UCI transmission cell configured with FDD.

The eNB <NUM> may receive <NUM> PDSCH HARQ-ACK information in the UCI transmission uplink subframe of the UCI transmission cell. This may be accomplished as described above in connection with <FIG>, for instance. For example, if the UCI transmission cell is a FDD cell, the first cell is a TDD, and the set of downlink subframe associations for the first cell includes the PDSCH association timing of the UCI transmission cell, the eNB <NUM> may receive <NUM> PDSCH HARQ-ACK information for the TDD cell in an UL (e.g., PUCCH or PUSCH) of the FDD cell.

<FIG> illustrates various components that may be utilized in a UE <NUM>. The UE <NUM> described in connection with <FIG> may be implemented in accordance with the UE <NUM> described in connection with <FIG>. The UE <NUM> includes a processor <NUM> that controls operation of the UE <NUM>. The processor <NUM> may also be referred to as a central processing unit (CPU). Memory <NUM>, which may include read-only memory (ROM), random access memory (RAM), a combination of the two or any type of device that may store information, provides instructions 1065a and data 1067a to the processor <NUM>. A portion of the memory <NUM> may also include non-volatile random access memory (NVRAM). Instructions 1065b and data 1067b may also reside in the processor <NUM>. Instructions 1065b and/or data 1067b loaded into the processor <NUM> may also include instructions 1065a and/or data 1067a from memory <NUM> that were loaded for execution or processing by the processor <NUM>. The instructions 1065b may be executed by the processor <NUM> to implement one or more of the methods <NUM> and <NUM> described above.

The UE <NUM> may also include a housing that contains one or more transmitters <NUM> and one or more receivers <NUM> to allow transmission and reception of data. The transmitter(s) <NUM> and receiver(s) <NUM> may be combined into one or more transceivers <NUM>. One or more antennas 1022a-n are attached to the housing and electrically coupled to the transceiver <NUM>.

<FIG> illustrates various components that may be utilized in an eNB <NUM>. The eNB <NUM> described in connection with <FIG> may be implemented in accordance with the eNB <NUM> described in connection with <FIG>. The eNB <NUM> includes a processor <NUM> that controls operation of the eNB <NUM>. The processor <NUM> may also be referred to as a central processing unit (CPU). Memory <NUM>, which may include read-only memory (ROM), random access memory (RAM), a combination of the two or any type of device that may store information, provides instructions 1179a and data 1181a to the processor <NUM>. A portion of the memory <NUM> may also include non-volatile random access memory (NVRAM). Instructions 1179b and data 1181b may also reside in the processor <NUM>. Instructions 1179b and/or data 1181b loaded into the processor <NUM> may also include instructions 1179a and/or data 1181a from memory <NUM> that were loaded for execution or processing by the processor <NUM>. The instructions 1179b may be executed by the processor <NUM> to implement one or more of the methods <NUM> and <NUM> described above.

The eNB <NUM> may also include a housing that contains one or more transmitters <NUM> and one or more receivers <NUM> to allow transmission and reception of data. The transmitter(s) <NUM> and receiver(s) <NUM> may be combined into one or more transceivers <NUM>. One or more antennas 1180a-n are attached to the housing and electrically coupled to the transceiver <NUM>.

The various components of the eNB <NUM> are coupled together by a bus system <NUM>, which may include a power bus, a control signal bus and a status signal bus, in addition to a data bus. The eNB <NUM> may also include a digital signal processor (DSP) <NUM> for use in processing signals. The eNB <NUM> may also include a communications interface <NUM> that provides user access to the functions of the eNB <NUM>. The eNB <NUM> illustrated in <FIG> is a functional block diagram rather than a listing of specific components.

<FIG> is a block diagram illustrating one configuration of a UE <NUM> in which systems and methods for performing carrier aggregation may be implemented. The UE <NUM> includes transmit means <NUM>, receive means <NUM> and control means <NUM>. The transmit means <NUM>, receive means <NUM> and control means <NUM> may be configured to perform one or more of the functions described in connection with <FIG>, <FIG> and <FIG> above. <FIG> above illustrates one example of a concrete apparatus structure of <FIG>. Other various structures may be implemented to realize one or more of the functions of <FIG>, <FIG> and <FIG>. For example, a DSP may be realized by software.

<FIG> is a block diagram illustrating one configuration of an eNB <NUM> in which systems and methods for performing carrier aggregation may be implemented. The eNB <NUM> includes transmit means <NUM>, receive means <NUM> and control means <NUM>. The transmit means <NUM>, receive means <NUM> and control means <NUM> may be configured to perform one or more of the functions described in connection with <FIG>, <FIG> and <FIG> above. <FIG> above illustrates one example of a concrete apparatus structure of <FIG>. Other various structures may be implemented to realize one or more of the functions of <FIG>, <FIG> and <FIG>. For example, a DSP may be realized by software.

The term "computer-readable medium" refers to any available medium that can be accessed by a computer or a processor. The term "computer-readable medium," as used herein, may denote a computer- and/or processor-readable medium that is non-transitory and tangible. By way of example, and not limitation, a computer-readable or processor-readable medium may comprise RAM, ROM, EEPROM, CD-ROM or other optical disk storage, magnetic disk storage or other magnetic storage devices, or any other medium that can be used to carry or store desired program code in the form of instructions or data structures and that can be accessed by a computer or processor. Disk and disc, as used herein, includes compact disc (CD), laser disc, optical disc, digital versatile disc (DVD), floppy disk and Blu-ray (registered trademark) disc where disks usually reproduce data magnetically, while discs reproduce data optically with lasers.

It should be noted that one or more of the methods described herein may be implemented in and/or performed using hardware. For example, one or more of the methods described herein may be implemented in and/or realized using a chipset, an application-specific integrated circuit (ASIC), a large-scale integrated circuit (LSI) or integrated circuit, etc..

Each of the methods disclosed herein comprises one or more steps or actions for achieving the described method. The method steps and/or actions may be interchanged with one another and/or combined into a single step without departing from the scope of the claims. In other words, unless a specific order of steps or actions is required for proper operation of the method that is being described, the order and/or use of specific steps and/or actions may be modified without departing from the scope of the claims.

Claim 1:
A user equipment, UE, (<NUM>) for performing carrier aggregation, comprising:
a processor;
memory in electronic communication with the processor, wherein instructions stored in the memory are executable to:
send Hybrid Automatic Repeat Request Acknowledgement/Negative Acknowledgement, HARQ-ACK, information on a primary cell, in response to Physical Downlink Shared Channel, PDSCH, transmission;
wherein, in a case that the UE (<NUM>) is configured to use at least one frequency division duplexing, FDD, cell and at least one time division duplexing, TDD, cell, the UE (<NUM>) is configured to use an FDD cell as the primary cell, the UE (<NUM>) is configured to use a TDD cell as a secondary cell, and both the PDSCH transmission and physical downlink control channel, PDCCH, transmission indicating the PDSCH transmission occur in a subframe n-<NUM> of the secondary cell, the HARQ-ACK information is sent in a subframe of the primary cell in accordance with PDSCH HARQ-ACK associations, in response to the PDSCH transmission,
the PDSCH HARQ-ACK associations are associations between a) PDSCH HARQ-ACK transmissions in HARQ-ACK reporting subframes and b) PDSCH transmissions in subframes including a downlink subframe and a special subframe,
an interval between the PDSCH HARQ-ACK transmissions and the PDSCH transmissions is fixed to <NUM> subframe interval, and
subframe n is determined as the subframe for sending the HARQ ACK information based on the fixed <NUM> subframe interval.