BR112016026166B1 - HARQ HD-FDD OPERATION - Google Patents

Abstract

HARQ HD-FDD OPERATION These are methods, systems and devices for hybrid automatic repeat request (HARQ) operation of half-duplex frequency division duplexing (HD-FDD). The base station may receive a message from a user equipment (UE) indicative of a duplexing capability of the UE. The base station can then select a HARQ process threshold based on the duplexing capability. In some examples, the base station may anticipate a collision between an uplink (UL) transmission and a downlink (DL) subframe based on the selected HARQ process limit. The base station can then schedule a transmission to avoid the anticipated collision. In some instances, the base station may limit various available settings for the channel quality indicator (CQI) or for a precoding matrix indicator (PMI).

Description

CROSS REFERENCES

[0001] The present patent application claims priority of the patent application in the U.S. 14/706,856 to Sakhnini et al, entitled "HD-FDD HARQ Operation", filed May 7, 2015 and Provisional Patent Application in the U.S. 61/991,230 to Sakhnini et al, entitled "HD-FDD HARQ Operation", filed May 9, 2014; among which, each one is assigned to the assignee of this document.

BACKGROUND

[0002] The present invention relates, in general, to wireless communication and, more specifically, to the hybrid automatic repeat request (HARQ) operation of half-duplex frequency division duplexing (HD-FDD). Wireless communication systems are widely installed to deliver various types of communication content such as voice, video, packet data, messaging, broadcasting and so on. These systems may be multiple access systems capable of supporting communication with multiple users by sharing available system resources (eg time, frequency and power). Examples of such multiple access systems include code division multiple access (CDMA) systems, time division multiple access (TDMA) systems, frequency division multiple access (FDMA) systems, and orthogonal frequency division (OFDMA), for example a Long Term Evolution (LTE) system.

[0003] In general, a wireless multiple access communications system may include multiple base stations, each of which simultaneously supports communication to multiple mobile devices or to other user equipment (UE) devices. Base stations can communicate with UEs on upstream and downstream links. Each base station has a range of coverage, which can be called the coverage area of the cell. Some types of wireless devices can provide automated communication. Wireless automated devices can include those that implement machine-to-machine (M2M) or Machine-Type Communication (MTC) communication. M2M and/or MTC may refer to data communication technologies that allow devices to communicate with each other or with a base station without human intervention. For example, M2M and/or MTC may refer to communications from devices that integrate sensors or meters to measure or capture information and relay that information to a central server or application program that can use the information or present the information to interacting humans. with the program or with the application.

[0004] MTC devices can be used to collect information or enable automated behavior of machines. Examples of applications for MTC devices include smart metering, inventory monitoring, water level monitoring, equipment monitoring, healthcare monitoring, wildlife monitoring, meteorological and geological event monitoring, fleet management and tracking, remote security capture, physical access control, and transaction-based business pricing.

[0005] Some wireless devices, including some MTC devices, may be an appropriate low-cost (eg, low-power, low-complexity, etc.) means of wireless communication with a base station. However, in some cases, certain communications between a base station and a low-complexity MTC device may be inefficient or unmanageable if the base station fails to account for limitations of the MTC device. As a consequence, it may be beneficial to adapt the base station and/or network operation to account for operational constraints of certain user equipment, such as MTC devices.

SUMMARY OF THE INVENTION

[0006] The features described refer, in general, to one or more improved systems, methods and/or apparatus for hybrid automatic repeat request (HARQ) operation of half-duplex frequency division duplex (HD-FDD) that takes responsibility for, or compensates for, operating restrictions or capabilities of user equipment. The base station may receive a message from a user equipment (UE) indicative of a duplexing capability of the UE. The base station can then select a HARQ process threshold based on the duplexing capability. In some examples, the base station may anticipate a collision between an uplink (UL) transmission and a downlink (DL) subframe based on the selected HARQ process limit. The base station can then schedule a transmission to avoid the anticipated collision. In some instances, the base station may limit various available settings for the channel quality indicator (CQI) or for a precoding matrix indicator (PMI).

[0007] A method of operation of HARQ HD-FDD is described. The method may include receiving a message from a UE indicative of a duplexing capability of the UE and selecting a HARQ process threshold based, at least partially, on the duplexing capability of the UE.

[0008] An apparatus for operation of HARQ HD-FDD is described. The apparatus may include means for receiving a message from a UE indicative of a duplexing capability of the UE and means for selecting a HARQ process threshold based at least partially on the duplexing capability of the UE.

[0009] An additional apparatus for operation of HARQ HD-FDD is described. The apparatus may include a processor, memory in electronic communication with the processor, and instructions stored in the memory, the instructions being executable by the processor to cause the apparatus to receive a message from a UE indicative of a duplexing capability of the UE and select a HARQ process limit based at least partially on the duplexing capability of the UE.

[0010] A non-transient computer-readable medium for HARQ HD-FDD operation is also described. Non-transient media may store code that may include executable instructions for receiving a message from a UE indicative of a UE's duplexing capability and selecting a HARQ process limit based, at least partially, on the UE's duplexing capability .

[0011] In some examples of the non-transient methods, apparatus, or computer-readable media described herein, the message identifies the duplexing capability of the UE. In some examples, the HARQ process boundary may be or may include a scheduling mode for the UE. In some examples, the duplexing capability of the UE is an HD-FDD capability.

[0012] In some examples of the non-transient methods, apparatus, or computer-readable media described herein, the HARQ process limit includes a restriction to less than eight (8) UL HARQ processes. In some examples, the HARQ process limit comprises a restriction to three (3) UL HARQ processes.

[0013] Some examples of the non-transient method, apparatus or computer-readable media described in this document may additionally include computer-executable resources, means and/or instructions for anticipating a collision between a UL transmission and a DL subframe with based on the selected HARQ process limit and schedule a transmission to avoid the early collision. Some examples include scheduling the transmission to avoid the early collision that comprises puncturing a UL subframe.

[0014] In some examples of the non-transient method, apparatus, or computer-readable media described herein, puncturing a UL subframe includes withholding the transmission of a UL grant. In some examples, puncturing a UL subframe includes suspending a UL retransmission by transmitting an early acknowledgment (ACK) message.

[0015] Some examples of the non-transient method, apparatus, or computer-readable media described in this document may additionally include computer-executable facilities, means, and/or instructions for transmitting a UL grant to continue an HARQ transmission in a subframe subsequent collision by avoiding the anticipated collision. Some examples comprise the DL subframe comprising a zero subframe (SF0) or a five subframe (SF5).

[0016] In some examples of the method, apparatus or non-transient computer-readable media include a (PBCH) transmission, a paging transmission, a system information message or a synchronization channel.

[0017] Some examples of the non-transient method, apparatus, or computer-readable media described in this document may additionally include computer-executable resources, means, and/or instructions to limit various configurations available for CQI or for PMI.

[0018] The further scope of applicability of the described methods and apparatus will become apparent from the detailed description, claims and drawings below. The detailed description and specific examples are provided by way of illustration only, as various changes and modifications within the scope of the description will be apparent to those skilled in the art.

BRIEF DESCRIPTION OF THE DRAWINGS

[0019] A further understanding of the nature and advantages of the present disclosure may be realized by reference to the following drawings. In the accompanying Figures, similar components or features may have the same reference marking. Furthermore, several components of the same type can be distinguished by following the reference marking by a dash and a second marking that distinguishes between similar components. If only the first reference tag is used in the descriptive report, the description is applicable to any of the similar components that have the same first reference tag regardless of the second reference tag.

[0020] Figure 1 illustrates an example of a wireless communications system in accordance with various aspects of the present disclosure;

[0021] Figure 2 illustrates an example of communication within a wireless communication system that supports operation of HARQ HD-FDD in accordance with various aspects of the present disclosure;

[0022] Figure 3A illustrates an example of a schedule based on three (3) HARQ HD-FDD processes, in accordance with various aspects of the present disclosure;

[0023] Figure 3B illustrates an example of a programming based on (1) HARQ HD-FDD process, in accordance with various aspects of the present disclosure;

[0024] Figure 4A illustrates an example of a schedule for HARQ HD-FDD operation in accordance with various aspects of the present disclosure;

[0025] Figure 4B illustrates an example of a schedule for HARQ HD-FDD operation in accordance with various aspects of the present disclosure;

[0026] Figure 5 shows a block diagram of a device that supports HARQ HD-FDD operation, in accordance with various aspects of the present disclosure;

[0027] Figure 6 shows a block diagram of a device that supports HARQ HD-FDD operation, in accordance with various aspects of the present disclosure;

[0028] Figure 7 shows a block diagram of a device that supports HARQ HD-FDD operation, in accordance with various aspects of the present disclosure;

[0029] Figure 8 illustrates a block diagram of a system supporting HARQ HD-FDD operation in accordance with various aspects of the present disclosure;

[0030] Figure 9 shows a flow chart illustrating a method for operating HARQ HD-FDD in accordance with various aspects of the present disclosure;

[0031] Figure 10 shows a flow chart illustrating a method for operating HARQ HD-FDD in accordance with various aspects of the present disclosure; It is

[0032] Figure 11 shows a flow chart illustrating a method for operating HARQ HD-FDD in accordance with various aspects of the present disclosure.

DETAILED DESCRIPTION

[0033] The features described refer, in general, to one or more improved systems, methods and/or apparatus for hybrid automatic repeat request (HARQ) operation of half-duplex frequency division duplexing (HD-FDD). User equipment, including MTC devices, employing HD-FDD communications can switch a radio from transmit mode to receive mode in order to communicate bi-directionally with a base station. That is, the device may not be able to transmit and receive simultaneously. There may be a delay (eg 1ms) associated with transitioning (eg switching) from transmit mode to receive mode. This delay can interfere with synchronous uplink (UL) HARQ operation, where there can be a constant delay (for example, 4ms or subframes) between the UL subframes and the associated downlink (DL) HARQ response. . In synchronous UL HARQ operation, there can also be a constant delay between DL control frames and UL subframes. HD-FDD operation can result in circumstances where a device is not able to receive (or transmit) the proper response since it is in the wrong radio mode. As a consequence, a base station may adjust its operation relative to an MTC device (or other user equipment) to take responsibility for such HD-FDD operation.

[0034] The base station MAY receive a message from a user equipment (UE) indicative of a duplexing capability of the UE. The base station can then select a HARQ process threshold based on the duplexing capability. In some examples, the base station may anticipate a collision between an uplink (UL) transmission and a downlink (DL) subframe based on the selected HARQ process limit. The base station can then schedule a transmission to avoid the anticipated collision. In some instances, the base station may limit various available settings for the channel quality indicator (CQI) or for a precoding matrix indicator (PMI). In this way, a base station can enable an HD-FDD device (e.g. an MTC device) to perform synchronous UL HARQ processes while avoiding conflicts between the timing for the uplink and downlink transmissions. downward.

[0035] The following description provides examples and does not limit the scope, applicability or configuration presented in the claims. Changes may be made in the function and arrangement of the elements discussed without departing from the scope of the disclosure. The various modalities may omit, replace, or add various procedures or components, as appropriate. For example, the methods described may be performed in a different order than described, and multiple steps may be added, omitted, or combined. Additionally, the features described in relation to certain modalities can be combined in other modalities.

[0036] Figure 1 illustrates an example of a wireless communication system 100 in accordance with various embodiments. The system 100 includes base stations 105, communication devices, also known as a user equipment, user equipment (UE) 115, and a core network 130. The base stations 105 can communicate with the UEs 15 under control of a base station controller (not shown) which may form part of the core network 130 or the base stations 105 in various embodiments. Base stations 105 may communicate control information and/or user data with main network 130 via return traffic links 132. In embodiments, base stations 105 may communicate, directly or indirectly, with each other. the other through return traffic links 134 which may be wired or wireless communication links. System 100 can support operation on multiple carriers (waveform signals of different frequencies). The wireless communication links 125 can be modulated according to various radio technologies. Each modulated signal can carry control information (eg reference signals, control channels, etc.), overload information, data, etc.

[0037] Bidirectional communications between a base station 105 and a UE 115 can be achieved according to a process known as duplexing. For example, devices (e.g., a base station 105 or a UE 115) can communicate according to a time division duplexing (TDD) method in which a single frequency band can be used for both uplink as for downlink. The devices can also communicate according to a frequency division duplexing (FDD) method in which different frequencies are used for uplink and downlink. Devices can also use full-duplex (FD) or half-duplex (HD) communication methods. A FD device can transmit and receive simultaneously. An HD device can switch between transmitting and receiving. Some devices may be capable of more than one communication mode. For example, a device might be capable of both TDD and FDD or both FD and HD communications.

[0038] The base stations 105 can communicate wirelessly with the UEs 115 through one or more base station antennas. Each of the base station locations 105 may provide communication coverage for a respective geographic coverage area 110. In some embodiments, the base stations 105 may be referred to as a transceiver base station, a radio base station, a access point, a radio transceiver, a basic service set (BSS), an extended service set (ESS), a NodeB, evolved B-node (eNB), Home NodeB, a Home eNodeB, or other suitable terminology. The geographic coverage area 110 for a base station can be divided into sectors that form a portion of the coverage area (not shown). The system 100 may include base stations 105 of different types (e.g. macro, micro and/or pico base stations). There may be overlapping coverage areas for different technologies.

[0039] The system 100 may be a Heterogeneous Long Term Evolution (LTE/LTE-A) network in which different types of base stations provide coverage for various geographic regions. For example, each base station 105 can provide communication coverage for a macrocell, a picocell, a femtocell, and/or other cell types. A macrocell usually covers a relatively large geographic area (for example, several kilometers in radius) and can allow unrestricted access by UEs with service subscriptions with the network provider. A picocell generally covers a relatively smaller geographic area and can allow unrestricted access by UEs with service subscriptions with the network provider. A femtocell also usually covers a relatively small geographic area (e.g., a household) and, in addition to unrestricted access, can also provide restricted access by UEs that have an association with the femtocell.

[0040] The core network 130 can communicate with the base stations 105 via a return traffic link 132 (eg, SI etc.). The base stations 105 can also communicate with each other, for example, directly or indirectly through return traffic links 134 (e.g. X2 etc.) and/or through return traffic links 132 (e.g. , via main network 130). Wireless communications system 100 can support synchronous or asynchronous operation. For synchronous operation, base stations can have similar frame timing, and transmissions from different base stations can be approximately time-aligned. For asynchronous operation, base stations may have different frame timing, and transmissions from different base stations may not be time-aligned. The techniques described in this document can be used for both synchronous and asynchronous operations.

[0041] The UEs 115 can be dispersed throughout the wireless communication system 100, and each UE can be stationary or mobile. A UE 15 may also be referred to by those skilled in the art as a mobile station, subscriber station, mobile unit, subscriber unit, wireless unit, remote unit, mobile device, wireless device, wireless communications device, remote device, mobile subscriber station, access terminal, mobile terminal, wireless terminal, remote terminal, handset, user agent, mobile client, client or some other suitable terminology. A UE 115 can be a TCM device, a cell phone, a personal digital assistant (PDA), a wireless modem, a wireless communication device, a handheld device, a tablet-type computer, a laptop-type computer , a cordless phone, a wireless local circuit (WLL) station, or the like. A UE may have the ability to communicate with macroeNBs, picoeNBs, femtoeNBs, relays, and the like. Some of the UEs 115 within the system 100 may be low complexity MTC devices configured for HD-FDD communication.

[0042] The wireless communication link 125 shown in the system 100 may include uplink (UL) transmissions from a UE 115 to a base station 105, and/or downlink (DL) transmissions from a base station 105 to a UE 115 via DL carriers. Downlink transmissions can also be called forward link transmissions whereas uplink transmissions can also be called reverse link transmissions. Base stations 105 may receive a message over a wireless communication link 125 from a UE 115, such as a low complexity MTC device, indicative of a duplexing capability of UE 115. Base station 105 , or in embodiments the core network 130, may select a HARQ process limit based on the duplexing capability of the UE 115.

[0043] Figure 2 illustrates an example of wireless communication 200 within a system (eg, system 100 of Figure 1) configured for HARQ HD-FDD operation in accordance with various modalities. Example 200 may include a UE 115-a (e.g., an MTC device) and a base station 105-a which may be examples of a UE 115 and a base station 105 of Figure 1. The base station 105 -a can receive a 205 message from the UE that indicates a duplex capability. For example, the message may explicitly state that the UE is an HD-FDD device. In another example, base station 105-a may infer based on another aspect of the message (or based on multiple transmissions from the UE) that UE 115-a is an HD-FDD device. In some examples, UE 115-a may be capable of other modes of operation, but may be operating concurrently in HD-FDD mode, for example, to convert power.

[0044] Based on message 205, base station 105-a may select a HARQ process limit 210. Base station 105-a may select a maximum number of concurrent HARQ UL processes to be scheduled. For example, there may be a constant delay (for example, a 4ms delay) between a DL transmission of a resource grant, a UL transmission, and/or a DL acknowledgment (ACK)/negative acknowledgment (NACK). In this way, the base station 105-a can limit the number of HARQ processes to 3 so that the UE 115-a can have time to do a radio switch between UL and DL HARQ frames.

[0045] In some cases, the base station 105-a may also anticipate collisions 215 between UL transmissions and DL transmissions based on the selected HARQ process limit. Base station 105-a can then schedule transmissions to avoid collisions. For example, scheduling the transmission to avoid early collision includes punching a UL subframe. In some examples, puncturing a UL subframe includes abstaining from transmitting a UL grant. In some examples, puncturing a UL subframe includes suspending a UL retransmission by transmitting an early ACK message (or an ACK in place of a NACK). Base station 105-a may transmit an UL grant to continue a HARQ transmission in a subsequent subframe after the anticipated collision. For example, the DL subframe can be a zero subframe (SF0) or a five subframe (SF5). That is, in a system that specifies 10 subframes in each 10ms frame with subframe numbers from 0 to 9, the DL subframes that the base station can schedule can be either the first subframe (SF0) or the sixth subframe (SF5 ). The DL subframe may be or may include a physical broadcast channel (PBCH) transmission, a paging transmission, a system information message, or a synchronization channel. The 10-to-5 base station can limit various available settings for the channel quality indicator (CQI) or for a precoding matrix indicator (PMI).

[0046] Base station 105-a may then send a DL transmission 225 to UE 115-a based on the HARQ process limit and/or scheduling in order to avoid collisions. For example, the DL broadcast may be a resource grant for a UL broadcast 230. In some examples, the UE 115-a may perform a radio switch 220-a from transmit mode to receive mode prior to transmission. 225. UE 115-a may then perform another radio switch 220-b from receive mode to transmit mode in order to make a UL 230 transmission. The base station may receive the UL 230 transmission and sending an ACK 235. The UE 115-a may perform another radio switch 220-c to receive the ACK. In general, the UE 115-a may perform a radio switch 220 after sending or receiving multiple transmissions based on the HARQ process limit. For example, UE 115-a may transmit 3 subframes and then perform a radio switch 220 to receive an ACK or NACK for each of the subframes. This may allow UE 115-a to send and receive transmissions according to a synchronous schedule with a delay of 4 subframes.

[0047] Figure 3A illustrates an example of a 301 schedule based on three (3) HARQ HD-FDD operations, in accordance with various embodiments. In some cases, HD-FDD operations include a delay of 1 subframe (e.g. 1 ms) for a UE 115 to complete a transmit-to-receive (Tx-to-Rx) and receive-to-transmit switch (Rx-to-Tx). In some examples, HD-FDD operation may be defined as part of an LTE "Frame Structure Type 1". In this way, HD-FDD can follow the HARQ timeline defined for Frame Structure Type 1. That is, it can employ synchronous programming to program UL HARQ operations. For example, there may be a delay of 4 subframes between Physical Uplink Shared Channel (PUSCH) transmissions and HARQ-ACK transmissions. There may also be a delay of 4 subframes between Physical Downlink Control Channel (PDCCH) transmissions, Evolved PDCCH (EPDCCH) or Physical HARQ Indicator Channel (PHICH) transmissions, and PUSCH transmissions.

[0048] Scheduling for an HD-FDD UE that initiates UL data transfer may be triggered primarily by UL HARQ limitations. In some examples, the maximum number of UL HARQ processes may be limited to 3. That is, three DL transmissions (e.g., DL HARQ subframes) 305 may be sent by a base station 105 after which one UE 115 may perform a radio switch 315 lasting one subframe. In some examples, DL transmissions (e.g., HARQ subframes of DL) 305 may include allowances for a UL transmission or for an ACK/NACK transmission. Then, UE 115 may transmit three UL 310 transmit/retransmit subframes, followed by another radio switch 315. UE 115 UL 310 transmit/retransmit subframe 315 may include data transmissions or retransmissions based on a NACK from the station -base 105. Each subframe in a frame can be numbered from 0 to 9. Whereas for a HARQ process cycle based on a HARQ process limit of 3 8 subframes may be required and there are 10 subframes in each frame , HARQ processes may not be synchronized with frame numbers. That is, the least common multiple of 8 and 10 is 40, so the HARQ process can loop five times (40 subframes) before starting at a subframe that has the same subframe number.

[0049] Figure 3B illustrates an example of a 302 schedule based on one (1) HARQ HD-FDD process, in accordance with various embodiments. Downlink (DL) HARQ subframes 305 may be used for downlink transmissions associated with a HARQ process (e.g., a resource grant or ACK/NACK subframes). For a single transmission (or retransmission) of UL 310, 4 subframes may be programmed before and after each HARQ subframe of DL 305. A radio switch 315 may be performed before and after each transmission/retransmission subframe of UL 310. Additional or non-HARQ related HARQ 320 can be programmed as well so there is a 4ms delay for synchronous HARQ UL operations. As in Figure 3A, the cycle can consist of 8 subframes so that after 5 cycles, the HARQ process starts at the subframe with the same number. In some examples, a schedule might be based on a HARQ process of 2 as well as 1 or 3, as depicted in Figures 3A and 3B.

[0050] Figure 4A illustrates an example of a programming 401 for the operation of HARQ HD-FDD, in accordance with various embodiments. Schedule 401 may include a cycle of 3 HARQ processes and may incorporate aspects of Figure 3A. Additionally, schedule 401 shows exemplary scheduler behavior for 3 UL HARQ processes with UL puncturing to maintain the PBCH. Three HARQ subframes of DL 305 may be followed by a radio switch 315, followed by three transmit/retransmit subframes of UL 310, followed by another radio switch 315. However, programming 401 may be changed to ensure that each SF0 410 occurs in a HARQ subframe of DL 305. PBCH transmissions can be sent in SF0 410 of each radio frame, so if SF0 falls in a transmit/retransmit subframe of UL 310 or a switch subframe of radio 315, the UE may not be able to receive the PBCH transmissions.

[0051] Changing the schedule may be known as "punching" the HARQ process schedule. That is, a network scheduler (e.g., at a base station 105) can prevent the transmission of UL in SF0 410 of each radio frame by suspending the grant transmission for the retransmission of four (4) previously subframes (for example, in SF6) or by suspending UL retransmissions by sending an ACK in PHICH four (4) subframes earlier. DL subframes 405 represent subframes programmed in this manner. The scheduler (eg, base station 105) can then use the PDCCH to continue transmission of HARQs in subsequent subframes. This can result in improved reception of PBCH by UE 115. Reception of other DL messages, such as system information block 1 (SIB1) or paging messages, in subframes other than SF0 can be improved as well. manner depicted for the PBCH.

[0052] Figure 4B illustrates an example of a programming 402 for the operation of HARQ HD-FDD, in accordance with various embodiments. Schedule 402 may include a cycle of 3 HARQ processes and may incorporate aspects of Figure 3A and 4A. Additionally, schedule 402 shows an example of scheduler behavior for 3 UL HARQ processes with UL puncturing to maintain identification reliability of both the PBCH and the cell. That is, the DL HARQ subframes 305 may be followed by a radio switch 315, followed by the UL transmit/retransmit subframes 310, followed by another radio switch 315. However, scheduling 402 may be configured to ensure that every SF0 (or, in some cases, most SF0s) occur within a HARQ subframe of DL 305. The 402 schedule can also be configured to ensure that every SF5 415 (or, in some cases, the largest of the SF5s 415 ) occurs in a DL HARQ subframe 305 or in subframe 405, which may be a DL piercing subframe.

[0053] Figure 5 shows a block diagram 500 of a base station 105-b for HARQ HD-FDD operation in accordance with various embodiments. Base station 105-b can be an example of one or more aspects of a base station 105 described with reference to Figures 1 to 4. Base station 105-b can include a receiver 505, a HARQ operation module 510 and/or a transmitter 515. Base station 105-b may also include a processor. Each of these components can be in communication with each other.

[0054] The base station components 105-b may, individually or collectively, be deployed with an application-specific integrated circuit (ASIC) adapted to perform some or all of the applicable functions in hardware. Alternatively, the functions may be performed by one or more other processing units (or cores) in the at least one IC. In other embodiments, other types of circuitry (e.g., Structured/Platform ASICs, a field-programmable gate array (FPGA), or other semi-custom IC) that can be programmed in a manner known in the art may be used. The functions of each unit can also be implemented, partially or completely, with instructions embedded in a memory, formatted to be executed by one or more general purpose or specific application processors.

[0055] Receiver 505 may receive information such as packets, user data, and/or control information associated with various information channels (eg, control channels, data channels, etc.). Information may be passed to the HARQ operator module 510 and other base station components 105-b.

[0056] The HARQ operation module 510 may be configured to receive a message from a UE indicative of a duplexing capability of the UE. The HARQ operation module 510 can be configured to select a HARQ process threshold based, at least partially, on the duplexing capability of the UE.

[0057] Transmitter 515 may transmit the one or more signals received from other components of base station 105-b. In some embodiments, transmitter 515 may be co-located with receiver 505 in a transceiver module. Transmitter 515 can include a single antenna or can include a plurality of antennas.

[0058] Figure 6 shows a block diagram 600 of a base station 105-c for HARQ HD-FDD operation in accordance with various embodiments. Base station 105-c can be an example of one or more aspects of base stations 105 described with reference to Figures 1 to 5. Base station 105-c can include a receiver 505-a, a HARQ 510-a and/or a 515-a transmitter. Base station 105-c may also include a processor. Each of these components can be in communication with each other. The HARQ operation module 510-a may also include a duplex capability module 605 and a HARQ process module 610.

[0059] Base station components 105-c may be deployed, individually or collectively, with at least one ASIC adapted to perform some or all of the applicable functions in hardware. Alternatively, the functions may be performed by one or more other processing units (or cores) in the at least one IC. In other embodiments, other types of integrated circuits may be used (e.g., Structured/Platform ASICs, an FPGA or other semi-custom IC) that may be programmed in a manner known in the art. The functions of each unit can also be implemented, partially or completely, with instructions embedded in a memory, formatted to be executed by one or more general purpose or specific application processors.

[0060] The receiver 505-a can receive information that can be passed to the HARQ operator module 510-a and to other components of the base station 105-c. HARQ operating module 510-a may be configured to perform the operations described above with reference to Figure 5. Transmitter 515-a may transmit the one or more signals received from other components of base station 105-c.

[0061] The duplex capability module 605 may be configured to receive a message from a UE indicative of a duplex capability of the UE. In some examples, the message identifies the duplexing capability of the UE. In some examples, the duplexing capability of the UE may be an HD-FDD capability.

[0062] The HARQ process module 610 can be configured to select a HARQ process threshold based, at least partially, on the duplexing capability of the UE. In some examples, the HARQ process boundary may be or may include a scheduling mode for the UE. The HARQ process module 610 can be configured so that the HARQ process limit can include a restriction of less than eight (8) UL HARQ processes. In some examples, the HARQ process limit comprises a restriction to three (3) UL HARQ processes.

[0063] Figure 7 shows a block diagram 700 of a HARQ operation module 510-b for operation of HARQ HD-FDD in accordance with various embodiments. The HARQ operation module 510-b may be an example of one or more aspects of a HARQ operation module 510 described with reference to Figures 5 to 6. The HARQ operation module 510-b may include a capability module 605-a duplexing module and a 610-a HARQ process module. Each of these modules can perform the functions described above with reference to Figure 6. The HARQ process module 610-a can also include a programming module 705 and the HARQ operation module 510-b can also include a configuration module channel state information (CSI) 710.

[0064] The components of the HARQ 510-b operation module can be implemented, individually or collectively, with one or more ASICs adapted to perform all or part of the applicable functions in hardware. Alternatively, the functions may be performed by one or more other processing units (or cores) in the at least one IC. In other embodiments, other types of integrated circuits may be used (e.g., Structured/Platform ASICs, an FPGA or other semi-custom IC) that may be programmed in a manner known in the art. The functions of each unit can also be implemented, partially or completely, with instructions embedded in a memory, formatted to be executed by one or more general purpose or specific application processors.

[0065] Programming module 705 can be configured to anticipate a collision between a UL transmission and a DL subframe based on the selected HARQ process threshold. Scheduling module 705 can be configured to schedule a transmission to avoid early collision. In some examples, scheduling the transmission to avoid early collision comprises puncturing a UL subframe. In some examples, puncturing a UL subframe comprises withholding the transmission of a UL grant. In some examples, puncturing an UL subframe comprises suspending an UL retransmission by transmitting an early ACK message. Scheduling module 705 may also be configured to transmit an UL grant to continue a HARQ transmission in a subsequent subframe upon early collision avoidance. In some examples, the DL subframe comprises a zero subframe (SF0) or a five subframe (SF5).

[0066] The CSI 710 configuration module can be configured to select a configuration for either the CQI or the PMI. For example, it can limit a CSI configuration of a UE 115 based on the UE 115 operating in HD-FDD mode. For the Periodic CSI reporting configuration, since the timeline of UL HARQs can be aligned to 8 ms, all CQI/PMI settings (for example, the CQI/PMI settings defined in table 7.2. -1 A of 3GPP TS 36.213) may not be supported. For example, since the least common multiple of 8 (UL HARQ alignment) and 10 (number of subframes in a frame) is 40, it may not be possible to use a CQI/PMI (also called Npd) cycle of 5, 10 or 20 frames. That is, the CSI configuration module can limit the CQI and/or PMI configuration to more cycles that are multiples of 40.

[0067] Figure 8 shows a diagram of a system 800 for the operation of HARQ HD-FDD in accordance with various embodiments. System 800 may include a base station 105-d which may be an example of a base station 105 described with reference to Figures 1 and 7. Base station 105-d may include a HARQ operation module 810 which may being an example of a HARQ operation module described with reference to Figures 5 and 7. Base station 105-d may also include a broadcast module 825. Base station 105-d may include components for two-way voice communications and data, including components for transmitting communications and components for receiving communications. For example, base station 105 can communicate with other base stations 105 (not shown) via an X2 interface via, for example, base station communication module 830, or it can communicate with a UE of MTC 115-b or a non-MTC 115-c UE.

[0068] The broadcasting module 825 can be configured to send PBCH transmissions, system information messages, synchronization channels and other data that is directed to multiple UEs 115 in the geographic coverage area 110 of the base station 105. broadcasting module 825 may operate in coordination with transceiver 835 to transmit these messages and may coordinate with HARQ operating module 810 to adjust HARQ operating schedules to avoid collisions with broadcast information.

[0069] The base station 105-d may also include a processor module 805 and memory 815 (including software (SW) 820) and one or more antenna (or antennas) 840 that can communicate, directly or indirectly, a with one another (for example, via one or more 845 buses). Transceiver 835 may be configured to communicate bidirectionally, through antenna (or antennas) 840 and/or one or more wired or wireless links, with one or more networks, as described above. For example, transceiver 835 may be configured to communicate bi-directionally with a UE 115. Transceiver 835 may include a modem configured to modulate the packets and deliver the modulated packets to antenna (or antennas) 840 for transmission and for demodulation. packets received from antenna (or antennas) 840. While base station 105-d may include a single antenna 840, base station 105-d may also have multiple antennas 840 capable of concurrently transmitting and/or receiving multiple transmissions without wire. Transceiver 835 may also be capable of simultaneously communicating with one or more base stations 105.

[0070] Memory 815 can include Random Access Memory (RAM) and Read Only Memory (ROM). Memory 815 can store computer-readable, computer-executable software/firmware code 820 that contains instructions that, when executed, are configured to cause processor module 805 to perform various functions described herein (e.g., identifying capabilities of duplexing a UE 115, selecting a HARQ process limit, avoiding UL and PBCH HARQ transmission collisions, limiting CQI/PMI settings, etc.). Alternatively, software/firmware code 820 may not be directly executable by processor module 805 but may be configured to cause a computer (eg, when compiled and executed) to perform the functions described herein. Processor module 805 may include an intelligent hardware device, for example, a central processing unit (CPU), microcontroller, ASIC, etc., may include RAM and ROM. Memory 815 can store computer-readable, executable software/firmware code 820 that contains instructions that are configured to, when executed, cause processor module 805 to perform various functions described herein (e.g., call processing, database management, processing of carrier mode indicators, reporting CSI, etc.). Alternatively, software/firmware code 820 may not be directly executable by processor module 805 but may be configured to cause a computer (eg, when compiled and executed) to perform the functions described herein. Processor module 805 may include the intelligent hardware device, for example, a CPU, microcontroller, ASIC, etc.

[0071] Figure 9 shows a flowchart 900 illustrating a method for operating HARQ HD-FDD in accordance with various embodiments. Flowchart functions 900 may be implemented by a base station 105 or components thereof, as described with reference to Figures 1 to 8. In certain examples, flowchart blocks 900 may be implemented by the HARQ operation module described with references to Figures 5 to 8.

[0072] At block 905, base station 105 may receive a message from a UE indicative of a duplexing capability of the UE. For example, the message may state the UE capability explicitly, or the base station 105 may infer based on one or more messages that the UE is an HD-FDD device. In certain examples, block functions 905 may be implemented by duplexing capability module 605, as described above with reference to Figure 6.

[0073] In block 910, the base station 105 may select a HARQ process limit based, at least partially, on the duplexing capability of the UE. In certain examples, block functions 910 may be performed by HARQ process module 610, as described above with reference to Figures 6. In some examples, flowchart steps 900 may be performed by a network scheduler that is not co-located with a base station.

[0074] It should be noted that the flowchart method 900 is only one deployment and that the method operations and steps may be arranged or otherwise modified so that other deployments are possible.

[0075] Figure 10 shows a flowchart 1000 illustrating a method for operating HARQ HD-FDD in accordance with various embodiments. Flowchart functions 1000 may be implemented by a base station 105 or components thereof, as described with reference to Figures 1 to 8. In certain examples, flowchart blocks 1000 may be implemented by the HARQ operation module described with references to Figures 5 through 8. The method described in flowchart 1000 may also incorporate aspects of flowchart 900 of Figure 9.

[0076] In block 1005, base station 105 may receive a message from a UE indicative of a duplexing capability of the UE. For example, the message may state the UE capability explicitly, or the base station 105 may infer based on one or more messages that the UE is an HD-FDD device. In certain examples, block functions 1005 may be performed by duplexing capability module 605, as described above with reference to Figure 6.

[0077] In block 1010, the base station 105 may select a HARQ process limit based, at least partially, on the duplexing capability of the UE. In certain examples, block functions 1010 may be performed by HARQ process module 610, as described above with reference to Figure 6.

[0078] In block 1015, base station 105 may anticipate a collision between a UL transmission and a DL subframe based on the selected HARQ process threshold. In certain examples, block functions 1015 may be performed by programming module 705, as described above with reference to Figure 7.

[0079] In block 1020, base station 105 may schedule a transmission to avoid the anticipated collision. In certain examples, block functions 1020 may be implemented by programming module 705, as described above with reference to Figure 7.

[0080] It should be noted that the flowchart method 1000 is only one deployment and that the method operations and steps may be arranged or otherwise modified so that other deployments are possible.

[0081] Figure 11 shows a flowchart 1100 illustrating a method for operating HARQ HD-FDD in accordance with various embodiments. Flowchart functions 1100 may be implemented by a base station 105 or components thereof, as described with reference to Figures 1 to 8. In certain examples, flowchart blocks 1100 may be implemented by the HARQ operation module described with references to Figures 5 to 8. The method described in flowchart 1100 may also incorporate aspects of flowcharts 900 to 1000 of Figures 9 to 10.

[0082] In block 1105, base station 105 may receive a message from a UE indicative of a duplexing capability of the UE. For example, the message may state the UE capability explicitly, and/or the base station 105 may infer based on one or more messages that the UE is an HD-FDD device. In certain examples, block functions 1105 may be performed by duplexing capability module 605, as described above with reference to Figure 6.

[0083] In block 1110, base station 105 may select a HARQ process limit based, at least partially, on the duplexing capability of the UE. In certain examples, block functions 1110 may be performed by HARQ process module 610, as described above with reference to Figures 6.

[0084] In block 1115, base station 105 may limit various available settings for a CQI or for a precoding matrix (PMI) indicator. In certain examples, block functions 1115 may be performed by CSI configuration module 710, as described above with reference to Figures 7.

[0085] It should be noted that the flowchart method 1100 is only one deployment and that the method operations and steps may be arranged or otherwise modified so that other deployments are possible.

[0086] The techniques described in this document can be used for various wireless communication systems, such as code division multiple access (CDMA), time division multiple access (TDMA), frequency division multiple access ( FDMA), Orthogonal Frequency Division Multiple Accesses (OFDMA), Single Carrier Frequency Division Multiple Accesses (SC-FDMA) and other systems. The terms "system" and "network" are often used interchangeably. A CDMA system can deploy a radio technology such as CDMA2000, Universal Terrestrial Radio Access (UTRA), etc. CDMA2000 covers the IS-2000, IS-95 and IS-856 standards. IS-2000 releases 0 and A are commonly referred to as CDMA2000 1X, 1X, etc. IS-856 (TIA-856) is commonly referred to as 1xEV-DO of CDMA2000, High Rate Packet Data (HRPD), etc. UTRA includes Broadband CDMA (WCDMA) and other variants of CDMA. A TDMA system can deploy a radio technology such as the Global System for Mobile Communications (GSM). An OFDMA system can deploy a radio technology such as Ultra Mobile Broadband (UMB), Evolved UTRA (E-UTRA), IEEE 802.11, IEEE 802.16, IEEE 802.20, Flash-OFDM", etc. UTRA and E -UTRA are parts of Universal Mobile Telecommunication System (UMTS) Long Term Evolution (LTE) of 3GPP and LTE Advanced (LTE-A) are Universal Mobile Telecommunication System (UMTS) releases using E-UTRA. UTRA, E-UTRA, UMTS, LTE, LTE-A and Global System for Mobile Communications (GSM) are described in the organization's documents titled "3rd Generation Partnership Project" (3GPP). CDMA2000 and UMB are described in the documents from an organization called "Partnership Project on 3rd Generation 2" (3GPP2). The techniques described in this document can be used for the radio systems and technologies mentioned above, as well as other radio systems and technologies. The description below, however, it describes an LTE system by way of example, and LTE terminology is used throughout much of the description below, although the techniques are applicable beyond LTE applications.

[0087] The detailed description set forth above in connection with the accompanying drawings describes exemplary embodiments and does not represent only the embodiments that can be implemented or that are within the scope of the claims. The detailed description includes specific details for the purpose of providing an understanding of the described techniques. However, these techniques can be practiced without these specific details. In some examples, well-known structures and devices are shown in block diagram form in order to avoid incompressibility of the concepts of the described embodiments.

[0088] Information and signals can be represented using any of a variety of different technologies and set of procedures. For example, data, instructions, commands, information, signals, bits, symbols, and integrated circuits that can be referenced throughout the above description can be represented by voltages, electric currents, electromagnetic waves, particles or magnetic fields, particles or optical fields or any combination thereof.

[0089] The various illustrative blocks and modules described in connection with the disclosure herein may be implemented or realized with a general purpose processor, a digital signal processor (DSP), an ASIC, an FPGA or other programmable logic device, port separate or transistor logic, separate hardware components, or any combination thereof designed to perform the functions described herein. A general purpose processor may be a microprocessor, but alternatively, the processor may be any conventional processor, controller, microcontroller or state machine. A processor can also be deployed as a combination of computing devices, for example, a combination of a DSP and a microprocessor, multiple microprocessors, one or more microprocessors in conjunction with a DSP core, or any other such configuration.

[0090] The functions described in this document may be implemented in hardware, software executed by a processor, firmware, or any combination thereof. If implemented in software executed by a processor, functions may be stored or transmitted via one or more instructions or code on computer-readable media. Other examples and implementations are within the scope of the accompanying disclosure and claims. For example, due to the nature of software, the functions described above can be implemented using software running through a processor, hardware, firmware, wired connection, or combinations of any of these. Feature deployment functions can also be physically located in multiple locations, which includes being distributed such that portions of the functions are deployed in different physical locations. Additionally, as used herein, including the claims, "or" as used in a list of items (e.g., a list of items preceded by a phrase such as "at least one of" or "one or more of" ), indicates a disjunctive list so that, for example, a list of "at least one of A, B, or C" means A or B or C or AB or AC or BC or ABC (that is, A and B and C ).

[0091] Computer-readable media include both non-transient computer storage media and communication media, including any media that facilitates the transfer of a computer program from one location to another. Non-transient storage media can be any available media that can be accessed by a general-purpose or purpose-built computer. By way of example, but not limitation, non-transient computer readable media may comprise RAM, ROM, Electrically Erasable Programmable Read Only Memory (EEPROM), Compact Disk (CD) ROM or other optical disk storage, magnetic disk storage or other magnetic storage devices or any other non-transient media that can be used to carry or store desired program code medium in the form of instructions or data structures and that can be accessed by a general purpose or special purpose computer or by a general purpose or general purpose processor. Furthermore, any connection is appropriately termed computer-readable media. For example, if instructions are transmitted from a website, server, or other remote source using coaxial cable, fiber optic cable, twisted pair, digital signage line (DSL), or wireless technologies such as such as infrared, radio and microwave, then coaxial cable, fiber optic cable, twisted pair, DSL or wireless technologies such as infrared, radio and microwave are included in the definition of media. Magnetic disk and optical disk, as used herein, include CD, laser disk, optical disk, digital versatile disk (DVD), floppy disk and blu-ray disk, where magnetic disks often reproduce data magnetically, whereas optical discs reproduce data optically with lasers. Combinations of the foregoing are also included within the scope of computer-readable media.

[0092] The foregoing description of the disclosure is provided to enable anyone skilled in the art to produce or use the disclosure. Various modifications to such embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein can be applied to other variations without departing from the scope of the disclosure. Throughout the present disclosure, the terms "example" or "exemplary" indicate an example or occurrence and do not imply or require any preference for the example noted. Accordingly, the present disclosure is not to be limited to the embodiments set forth in this document, but is to be accorded the broadest scope consistent with the principles and innovative features disclosed in this document.

Claims (15)

1. Method (1000) of wireless communication, comprising at a base station: receiving (1005) a message (205) from a user equipment, UE, (115) indicative of operation in a division duplexing mode half-duplexing frequency, HD-FDD, and selecting (1010) a hybrid auto-repeat request process limit, HARQ, based, at least in part, on the HD-FDD capability of the UE (115), where the limit process HARQ is a maximum number of simultaneous uplink, UL, HARQ processes for scheduling, characterized by: anticipating (1015) a collision between an uplink transmission, UL, and a downlink, DL subframe, based on the HARQ process limit; and scheduling (1020), based on the selected HARQ process limit, the transmission of UL to avoid early collision. Method according to claim 1, characterized in that the message identifies the capability for HD-FDD of the UE. Method according to claim 1, characterized in that the HARQ process boundary comprises a scheduling mode for the UE. Method according to claim 3, characterized by the ability for HARQ to comprise a restriction to less than eight UL HARQ processes. Method according to claim 1, characterized by scheduling the transmission to avoid early collision comprising: punching a UL subframe. 6. Method according to claim 5, characterized in that it further comprises: transmitting an UL grant to continue a HARQ transmission in a subsequent subframe upon early collision avoidance. Method according to claim 4, characterized in that the DL subframe comprises a zero subframe, SF0, or a five subframe, SF5. Method according to claim 6, characterized in that the DL subframe comprises at least one of a physical broadcast channel transmission, PBCH, a paging transmission, a system information message or a synchronization channel. 9. Method according to claim 1, further comprising: limiting a diversity of available settings for a channel quality indicator, CQI, or a pre-coding matrix indicator, PMI. 10. Base station apparatus for wireless communication, comprising: means for receiving (505-a) a message from a user equipment, UE, indicative of (115) operation in a frequency division duplexing mode of half-duplexing, HD-FDD; and means for selecting (510) a hybrid auto-repeating request process limit, HARQ, based at least in part on the HD-FDD capability of the UE (115), wherein the HARQ process limit is a number maximum concurrent uplink, UL, HARQ processes for scheduling, further comprising: means for anticipating (705) a collision between an uplink, UL, transmission and a downlink, DL, subframe based on the HARW process; and means for scheduling (705), based on the selected HARQ process threshold, the UL transmission to avoid early collision. 11. Apparatus according to claim 10, characterized in that the message identifies the duplexing capability of the UE. Apparatus according to claim 10, characterized in that the means for scheduling transmission to avoid early collision comprises: means for puncturing an UL subframe. 13. Apparatus according to claim 12, further comprising: means for transmitting an UL grant to continue a HARQ transmission in a subsequent subframe upon early collision avoidance. Apparatus according to claim 10, further comprising: means for limiting a variety of available settings for the channel quality indicator, CQI, or a pre-coding matrix indicator, PMI. 15. Memory characterized by comprising instructions stored therein that, when executed, perform a method as defined in any one of claims 1 to 9.