Patent Description:
A current Long Term Evolution (Long Term Evolution, LTE) system includes two types of frame structures. A frame structure type <NUM> (as shown in <FIG>) is applied to a frequency division duplex (Frequency Division Duplexing, FDD) LTE system, and may be referred to as an "FDD frame structure". A frame structure type <NUM> (as shown in <FIG>) is applied to a time division duplex (Time Division Duplexing, TDD) LTE system, and may be referred to as a "TDD frame structure".

Each subframe (Subframe) in the frame structure type <NUM> and that in the frame structure type <NUM> both have a length of <NUM>. Currently, as shown in table <NUM>, seven uplink-downlink configurations exist in the TDD LTE system.

In an LTE system, to support hybrid automatic repeat, user equipment (User Equipment, UE) needs to feed back, to a base station by using a physical uplink control channel (Physical Uplink Control CHannel, PUCCH) and a physical uplink shared channel (Physical Uplink Shared CHannel, PUSCH), a hybrid automatic repeat request-acknowledgement (Hybrid Automatic Repeat reQuest-Acknowledgement, HARQ-ACK) of physical downlink shared channel (Physical Downlink Shared CHannel, PDSCH) transmission. The hybrid automatic repeat request-acknowledgement may also be referred to as an ACK (Acknowledgment, acknowledgment)/a NACK (Negative Acknowledgement, negative acknowledgement) for short. The UE needs to use a physical hybrid automatic repeat request indicator channel (Physical Hybrid-ARQ Indicator Channel, PHICH) to receive a HARQ-ACK corresponding to the PUSCH.

Currently, for the FDD LTE system, a HARQ-ACK corresponding to a PDSCH transmitted in a downlink subframe n-<NUM> is fed back in an uplink subframe n. For the TDD LTE system, a HARQ-ACK corresponding to a PDSCH transmitted in a downlink subframe n-k is fed back in an uplink subframe n. Herein, k belongs to a set K. A definition of K for each TDD uplink-downlink configuration is shown in table <NUM>.

For the TDD LTE system, a HARQ-ACK can be fed back in only an uplink subframe. It can be learned from table <NUM> that any value of k is greater than or equal to <NUM>, that is, a HARQ-ACK can be fed back after at least four subframes. As a result, a HARQ round trip time (Round-Trip Time, RTT) is relatively long, and a data transmission delay is relatively long.

In conclusion, in the current TDD LTE system, uplink control information such as a HARQ-ACK is not fed back in a timely manner, causing a long data transmission delay. Consequently, the TDD LTE system cannot effectively provide a low delay service. <NPL>, discusses a unified <NUM> design across spectrum types and bands.

In view of this, an apparatus, a method, and, a computer storage medium are provided in accordance with the independent claims, so as to resolve a problem that a data transmission delay is relatively long because uplink control information is not fed back in a timely manner.

According to a first aspect, an embodiment of the present invention provides a communications apparatus, and the apparatus includes:.

The fourth part is located in a tail of the first subframe. The first part is a symbol used for downlink control transmission and downlink data transmission;.

With reference to the first possible implementation of the first aspect, in a second possible implementation,
the first part is specifically a symbol used for downlink control transmission.

With reference to the second possible implementation of the first aspect, in a third possible implementation, a quantity of symbols included in the first part is <NUM>, a length of the guard period GP is one symbol, a quantity of symbols included in the third part is <NUM>, and a quantity of symbols included in the fourth part is <NUM>.

With reference to the second or third possible implementation of the first aspect, in a fourth possible implementation,.

With reference to any of the possible implementations of the first aspect and the first aspect, in an fifth possible implementation,
the first part includes five symbols, a length of the guard period GP is one symbol, the third part includes one symbol, and the fourth part includes five symbols.

With reference to any one of the first possible implementation of the first aspect and the first aspect, in a sixth possible implementation, the fourth part is located in a tail of the first subframe, or the third part is located in a tail of the first subframe.

With reference to any one of the first to the sixth possible implementations of the first aspect and the first aspect, in a seventh possible implementation, the apparatus is located in a terminal device, and the processing module is specifically configured to:
if uplink grant information corresponding to the fourth part is detected, determine that the fourth part is a symbol used for uplink transmission; or if uplink grant information corresponding to the fourth part is not detected, determine that the fourth part is a symbol used for downlink transmission.

According to a second aspect, an embodiment of the present invention provides a communications device, and the communications device includes the apparatus provided in the first aspect.

According to a third aspect, an embodiment of the present invention provides a communications device, and the communications device includes the apparatus provided in any one of the first to the seventh possible implementations of the first aspect.

With reference to the third aspect, in a first possible implementation, the communications device is a terminal device, and the processing module is specifically configured to:
if uplink grant information corresponding to the fourth part is detected, determine that the fourth part is a symbol used for uplink transmission; or if uplink grant information corresponding to the fourth part is not detected, determine that the fourth part is a symbol used for downlink transmission.

According to a fourth aspect, an embodiment of the present invention provides an information sending and receiving method, and the method includes:.

The first subframe further includes:
a fourth part: a symbol used for downlink transmission or a symbol used for uplink transmission.

With reference to the first possible implementation of the fourth aspect, in a second possible implementation,
the first part is specifically a symbol used for downlink control transmission;.

With reference to the second possible implementation of the fourth aspect, in a third possible implementation, a quantity of symbols included in the first part is <NUM>, a length of the guard period GP is one symbol, a quantity of symbols included in the third part is <NUM>, and a quantity of symbols included in the fourth part is <NUM>.

With reference to the any one of first and the second possible implementation of the second aspect and the second aspect, in a third possible implementation,.

With reference to any one of first to the third possible implementation of the second aspect and the second aspect, in an fourth possible implementation,
the first part includes five symbols, a length of the guard period GP is one symbol, the third part includes one symbol, and the fourth part includes five symbols.

With reference to any one of the first to fourth possible implementation of the second aspect and the second aspect, in a fifth possible implementation, the fourth part is located in a tail of the first subframe, or the third part is located in a tail of the first subframe.

With reference to any one of the first to the fifth possible implementations of the second aspect and the second aspect, in a sixth possible implementation, the communications device is a terminal device, and the determining, by a communications device, a frame structure of a serving cell includes:
if the communications device detects uplink grant information corresponding to the fourth part, determine that the fourth part is a symbol used for uplink transmission; or if the communications device does not detect uplink grant information corresponding to the fourth part, determine that the fourth part is a symbol used for downlink transmission.

The first subframe including the third part used for uplink control information transmission is introduced into a TDD frame structure, so that uplink control information can also be fed back in a subframe used for downlink transmission in the system. Therefore, the problem that a data transmission delay is relatively long because uplink control information is not fed back in a timely manner can be resolved, so as to reduce a user plane delay. In addition, because uplink control information can be quickly fed back, scheduling can be performed in a system in a timely manner according to the feedback uplink control information, and spectrum efficiency of the system is improved.

When the uplink control information is a HARQ-ACK, because the HARQ-ACK can also be fed back in the subframe used for downlink transmission, a HARQ RTT delay is reduced, and the user plane delay is reduced. In addition, because the HARQ-ACK can be quickly fed back, a scheduling algorithm can be adjusted in the system according to the feedback HARQ-ACK. Therefore, spectrum efficiency is improved.

In addition, in a current TDD system such as a TDD LTE system, in different uplink-downlink configurations, a quantity and locations of uplink subframes are inconsistent with a quantity and locations of downlink subframes. Therefore, each uplink-downlink configuration is corresponding to a value of k, that is, timing for feeding back a HARQ-ACK in the current TDD system is not unified. Consequently, implementation complexity and standardization complexity are relatively high.

Therefore, when the uplink control information is the HARQ-ACK, the first subframe may be used to feed back the HARQ-ACK as well as mainly used for downlink transmission, so that different uplink-downlink configurations may be corresponding to same HARQ-ACK timing. A problem that implementation complexity and standardization complexity are relatively high because HARQ-ACK timing in the current TDD system is not unified is resolved.

Further, the first subframe may further include the fourth part. The fourth part is a symbol used for downlink transmission or a symbol used for uplink transmission.

The fourth part may be dynamically configured as a symbol used for downlink transmission or a symbol used for uplink transmission, or may be half-statically configured as a symbol used for downlink transmission or a symbol used for uplink transmission. It should be noted that when the first subframe includes the fourth part, and the fourth part is a symbol used for uplink transmission, the third part in the first subframe may be a symbol used for only uplink control information transmission.

The first subframe is introduced to perform short transmission time interval (Transmission Time Interval, TTI) data transmission in the first part and/or the fourth part of the first subframe. The short TTI data transmission can reduce a user plane delay. Therefore, a low delay service can be provided by introducing the first subframe. That is, the fourth part may change dynamically, so that a service delay can be reduced without limiting an uplink-downlink configuration. Implementation is more flexible.

An information transmission apparatus, method, and system are provided, to resolve a problem that a data transmission delay is relatively long because uplink control information is not fed back in a timely manner.

A communications device determines a frame structure of a serving cell, and sends and receives information in the serving cell according to the determined frame structure of the serving cell.

In the determined frame structure of the serving cell, one radio frame includes at least one first subframe, and the first subframe includes the following three parts:.

A first subframe including a third part used for uplink control information transmission is introduced into a TDD frame structure, so that uplink control information can also be fed back in a subframe used for downlink transmission in the system. Therefore, the problem that a data transmission delay is relatively long because uplink control information is not fed back in a timely manner can be resolved, so as to reduce a user plane delay. In addition, because uplink control information can be quickly fed back, scheduling can be performed in a system in a timely manner according to the feedback uplink control information, and spectrum efficiency of the system is improved.

Further, the first subframe includes a fourth part. The fourth part is a symbol used for downlink transmission or a symbol used for uplink transmission.

The fourth part may be dynamically configured as a symbol used for downlink transmission or a symbol used for uplink transmission, or may be half-statically configured as a symbol used for downlink transmission or a symbol used for uplink transmission. It should be noted that the first subframe includes the fourth part, and when the fourth part is a symbol used for uplink transmission, the third part in the first subframe may be a symbol used for only uplink control information transmission.

The following provides description in detail with reference to accompanying drawings.

<FIG> shows a wireless communications system provided in an embodiment. As shown in <FIG>, the wireless communications system includes a terminal device <NUM> and an access network device <NUM>.

The terminal device <NUM> and the access network device <NUM> are configured to determine a frame structure of a serving cell, and send and receive information in the serving cell according to the determined frame structure of the serving cell.

The first subframe further includes a fourth part. The fourth part is a symbol used for downlink transmission or a symbol used for uplink transmission.

It should be noted that the first subframe includes the fourth part, and when the fourth part is a symbol used for uplink transmission, the third part in the first subframe may be a symbol used for only uplink control information transmission.

The wireless communications system shown in <FIG> includes but is not limited to various wireless communications systems using a TDD duplex manner, for example, a Time Division-Synchronous Code Division Multiple Access (Time Division-Synchronous Code Division Multiple Access, TD-SCDMA) system, a TDD LTE system, and various evolved wireless communications systems using the TDD duplex manner in the future.

The wireless communications system shown in <FIG> may be a single-carrier wireless communications system. A quantity of carriers configured for the terminal device <NUM> is <NUM>. The terminal device <NUM> performs information transmission by using one carrier at a time. Alternatively, the wireless communications system shown in <FIG> may be a multi-carrier wireless communications system. A quantity of carriers configured for the terminal device <NUM> is greater than <NUM>, and the terminal device <NUM> may perform information transmission by using multiple carriers at a time.

In the wireless communications system shown in <FIG>, the terminal device <NUM> may be a wireless terminal. The wireless terminal may be a device that provides voice and/or data connectivity for a user, a handheld device with a wireless connection function, or another processing device connected to a wireless modem. The wireless terminal may communicate with one or more core networks by using a radio access network (for example, RAN, Radio Access Network). The wireless terminal may be a mobile terminal such as a mobile phone (also referred to as a "cellular" phone), or a computer with a mobile terminal. For example, the wireless terminal may be a portable, pocket-sized, handheld, computer built-in, or in-vehicle mobile apparatus that exchanges voice and/or data with the radio access network. For example, the wireless terminal may be a device such as a personal communications service (PCS, Personal Communication Service) phone, a cordless phone, a Session Initiation Protocol (SIP) phone, a wireless local loop (WLL, Wireless Local Loop) station, or a personal digital assistant (PDA, Personal Digital Assistant). The wireless terminal may also be referred to as a subscriber unit (Subscriber Unit), a subscriber station (Subscriber Station), a mobile station (Mobile Station), a mobile (Mobile), a remote station (Remote Station), an access point (Access Point), a remote terminal (Remote Terminal), an access terminal (Access Terminal), a user terminal (User Terminal), a user agent (User Agent), a user device (User Device), or user equipment (User Equipment).

The access network device <NUM> may include a base station or a radio resource management device for controlling a base station, or may include a base station and a radio resource management for controlling the base station. The base station may be a macro base station or a micro base station, such as a small cell (small cell) or a pico cell (pico cell). The base station may be a home base station, such as a home NodeB (Home NodeB, HNB) or a home evolved NodeB (Home eNodeB, HeNB). The base station may include a relay node (relay) and the like.

For example, for a TDD LTE system, the access network device <NUM> may be an evolved NodeB (evolved NodeB, eNodeB), and the terminal device <NUM> may be UE. For a TD-SCDMA system, the access network device <NUM> may include a NodeB (NodeB) and/or a radio network controller (Radio Network Controller, RNC), and the terminal device <NUM> may be UE.

In a future wireless communications system such as a fifth-generation (<NUM>th Generation, <NUM>) mobile communications system, a radio access network and a core network may be combined. In this case, an access network device and a core network device are not distinguished from each other and may be collectively referred to as network devices. Therefore, the access network device <NUM> in the wireless communications system shown in <FIG> may also be a network device that performs radio transmission with the terminal device <NUM>.

The serving cell may be a cell, a carrier, or a frequency band on which the terminal device <NUM> and the access network device <NUM> perform information transmission. From the perspective of a terminal device side, the serving cell may be a serving cell configured by the access network device <NUM> for the terminal device <NUM>, a serving cell that serves the terminal device <NUM>, or a serving cell accessed by the terminal device <NUM>. From the perspective of an access network device <NUM> side, the serving cell may be a serving cell configured for the terminal device <NUM>. In addition, the serving cell may be referred to as a carrier (carrier).

Information may include one or more of data, control information, or a reference signal.

<FIG> is a flowchart in which a terminal device <NUM> or an access network device <NUM> determines a frame structure and performs information transmission in the wireless communications system shown in <FIG>. As shown in <FIG>, a procedure includes the following steps:.

In the procedure shown in <FIG>, the communications device may be the terminal device <NUM> or the access network device <NUM>.

The following separately describe step S401 and step S402 in detail.

A communications device determines a frame structure of a serving cell.

In this step, the terminal device <NUM> or the access network device <NUM> determines the frame structure of the serving cell. In the determined frame structure of the serving cell, one radio frame includes at least one first subframe, and the first subframe includes:.

Specifically, a subframe structure of the first subframe may include but is not limited to the following four examples:.

The first subframe consists of four parts: a first part: a symbol used for downlink control transmission; a second part: a guard period GP; a third part: a symbol used for uplink control transmission and/or sounding signal (Sounding Reference Signal, SRS) transmission; and a fourth part: a symbol used for downlink data transmission or a symbol used for uplink data transmission.

The symbol used for downlink data transmission herein may be a symbol used for physical downlink shared channel (PDSCH) transmission, or may be a symbol used for PDSCH transmission and downlink reference signal transmission. The symbol used for uplink data transmission herein may be a symbol used for physical uplink shared channel (PUSCH) transmission, or may be a symbol used for PUSCH transmission and demodulation reference signal transmission.

That is, in the first subframe, the first part is mainly used for downlink control (may include a downlink reference signal used for downlink control demodulation) transmission, the third part is used for uplink control information transmission and/or sounding reference signal SRS transmission, and the fourth part may be used for downlink data transmission or uplink data transmission.

It should be noted that in all the embodiments of the present invention, downlink control may include a physical downlink control channel PDCCH (and/or an enhanced physical downlink control channel EPDCCH) and/or a physical hybrid automatic repeat request indicator channel PHICH. The downlink control transmission may be physical downlink control channel (and/or an enhanced physical downlink control channel EPDCCH) transmission and/or physical hybrid automatic repeat request indicator channel transmission.

In example <NUM>, the fourth part may be located in a tail of the first subframe, for example, an order of the four parts in the first subframe may be: the first part, the second part, the third part, and the fourth part. <FIG> shows an example.

Specifically, in example <NUM>, a quantity of symbols corresponding to each part is not limited. Preferably, a maximum quantity of symbols corresponding to the first part is <NUM>, and a quantity of symbols corresponding to the third part is <NUM>. <FIG> shows an example of the first subframe. A quantity of symbols included in the first part is <NUM>, a length of the guard period GP is one symbol, a quantity of symbols included in the third part is <NUM>, and a quantity of symbols included in the fourth part is <NUM>.

The first subframe consists of four parts: a first part: a symbol used for downlink control transmission and downlink data transmission; a second part: a guard period GP; a third part: a symbol used for uplink control information transmission and/or sounding signal SRS transmission; and a fourth part: a symbol used for downlink data transmission or a symbol used for uplink data transmission.

The symbol used for downlink data transmission herein may be a symbol and downlink service volumes and a service volume of low delay services. Therefore, a low delay service can be provided without limiting an uplink-downlink configuration of the frame structure, so as to better match real-time uplink and downlink service volumes.

For example, if a low delay service at a current moment comes from downlink services, the fourth part may be dynamically determined, and a frame structure of a radio frame is shown in <FIG>; or if both uplink and downlink have a low delay service requirement at a current moment, the fourth part is dynamically determined, and a frame structure of a radio frame is shown in <FIG>.

<FIG> is a schematic structural diagram of a communications apparatus according to an embodiment. As shown in <FIG>, the communications apparatus includes a processing module <NUM> and a transceiver module <NUM>.

The processing module <NUM> is configured to determine a frame structure of a serving cell.

The transceiver module <NUM> is configured to send and receive information in the serving cell according to the frame structure, determined by the processing module <NUM>, of the serving cell.

Optionally, the first part is specifically a symbol used for downlink control transmission;.

Optionally, a quantity of symbols included in the first part is <NUM>, a length of.

S1302: The communications device sends and receives information in the serving cell according to the determined frame structure of the serving cell.

Optionally, a quantity of symbols included in the first part is <NUM>, a length of the guard period GP is one symbol, a quantity of symbols included in the third part is <NUM>, and a quantity of symbols included in the fourth part is <NUM>.

Optionally, the fourth part is located in a tail of the first subframe.

Optionally, the first part is specifically a symbol used for downlink control transmission and downlink data transmission;.

Optionally, the first part includes seven symbols, a length of the guard period GP is one symbol, the third part includes one symbol, and the fourth part includes five symbols; or
the first part includes eight symbols, a length of the guard period GP is one symbol, the third part includes one symbol, and the fourth part includes four symbols.

Optionally, the first part is specifically a symbol used for downlink control transmission and downlink data transmission;
the third part is specifically a symbol used for uplink control information transmission and/or sounding signal SRS transmission; and
time can be reduced, and a user plane delay can be reduced.

In example <NUM>, the fourth part may be located in a tail of the first subframe, for example, an order of the four parts in the first subframe may be: the first part, the second part, the third part, and the fourth part. <FIG> shows an example. In this order, an advantage is that a location of the second part GP remains unchanged regardless of whether the fourth part is used for downlink data transmission or uplink data transmission. Therefore, implementation complexity is reduced.

In example <NUM>, the third part may alternatively be located in the tail of the first subframe. In this case, when the fourth part is used for downlink data transmission, an order of the fourth parts in the first subframe is: the first part, the fourth part, the second part, and the third part; or when the fourth part is used for uplink data transmission, an order of the fourth parts in the first subframe is: the first part, the second part, the fourth part, and the third part. When the third part is located in the tail of the first subframe, an advantage is that when the fourth part is used for downlink transmission, if the first part and the fourth part belong to a same TTI, the first part is not separated from the fourth part by the second part and the third part. Therefore, implementation complexity is reduced and a decoding time is reduced.

Specifically, in example <NUM>, a quantity of symbols corresponding to each part is not limited. For example, the first part may include five symbols, a length of the guard period GP may be one symbol, the third part may include one symbol, and the fourth part may include five symbols. In this example, the first part and the fourth part have a same quantity of symbols, so as to simplify a design of a size of a data transport block.

The first subframe consists of three parts: a first part: a symbol used for downlink control transmission and downlink data transmission; a second part: a guard period GP; and a third part: a symbol used for uplink control information transmission and/or uplink data transmission. The symbol corresponding to the third part may further be used for sounding signal SRS transmission.

The symbol used for downlink data transmission herein may be a symbol used for PDSCH transmission, or may be a symbol used for PDSCH transmission and/or downlink reference signal transmission. The symbol used for uplink data transmission herein may be a symbol used for PUSCH transmission and a symbol used for demodulation reference signal transmission.

In example <NUM>, whether the third part is used for uplink data transmission may be dynamically configured. For example, if the terminal device <NUM> detects an uplink grant corresponding to the third part, the third part is used for uplink data transmission, and a subframe corresponding to the third part is the first subframe; or if the terminal device <NUM> does not detect an uplink grant, a subframe corresponding to the third part is a downlink subframe. In this case, dynamically configuring whether the third part is used for uplink data transmission may be equivalent to dynamically configuring some downlink subframes in a radio frame as the first subframe.

In addition, in example <NUM>, some uplink subframes in a radio frame may be dynamically configured as the first subframe. Therefore, a downlink low delay service may be provided by using the first part, and an uplink-downlink configuration is not limited.

In example <NUM>, whether the third part of the first subframe is used for uplink data transmission is dynamically determined, some downlink subframes in a radio frame are dynamically configured as the first subframe, or some uplink subframes in a radio frame are dynamically configured as the first subframe. Therefore, uplink and downlink low delay services can be provided without limiting an uplink-downlink configuration. For example, when an uplink low delay service is required, some downlink subframes in a frame structure may be dynamically changed into downlink subframes according to uplink and downlink service volumes and a service volume of low delay services, so as to provide an uplink low delay service. In addition, a low delay service can be provided without limiting an uplink-downlink configuration of the frame structure, so as to better match real-time uplink and downlink service volumes.

Fourth examples of the subframe structure of the first subframe are described above. In the first subframe, the fourth part may be used for downlink transmission, or may be used for uplink transmission. The fourth part may be dynamically configured as a symbol used for downlink transmission or a symbol used for uplink transmission, or may be half-statically configured as a symbol used for downlink transmission or a symbol used for uplink transmission. When the fourth part dynamically changes, optionally, the terminal device <NUM> or the access network device <NUM> may determine whether the fourth part is used for uplink transmission or downlink transmission in the following manners.

In manner <NUM>, for the terminal device <NUM>, if the terminal device <NUM> detects an uplink grant corresponding to the fourth part, the fourth part is a symbol used for uplink transmission; or if the terminal device <NUM> does not detect an uplink grant corresponding to the fourth part, the fourth part is a symbol used for downlink transmission.

Herein, the uplink grant corresponding to the fourth part may be a UL grant, and the uplink grant may be used to schedule uplink transmission of the fourth part.

In manner <NUM>, for the access network device <NUM>, if the access network device <NUM> sends an uplink grant corresponding to the fourth part, the fourth part is a symbol used for uplink transmission; or if the access network device <NUM> does not send an uplink grant corresponding to the fourth part, the fourth part is a symbol used for downlink transmission.

In manner <NUM>, for the terminal device <NUM>, the terminal device <NUM> receives downlink control information sent by the access network device <NUM>, and determines, according to the downlink control information, whether the fourth part of the first subframe is used for downlink transmission or uplink transmission.

For example, the downlink control information may be carried in the first part of the first subframe, and a domain in the downlink control information is used to indicate whether the fourth part is used for downlink transmission or uplink transmission. For example, when the domain is a first value (for example, <NUM>), the fourth part is used for downlink transmission; or when the domain is a second value (for example, <NUM>), the fourth part is used for uplink transmission.

For another example, the downlink control information may be carried in a first subframe in a radio frame and the downlink control information may indicate each first subframe in the radio frame. For example, if a quantity of first subframes in one radio frame is <NUM>, the downlink control information may include <NUM> bits, and each bit is corresponding to one first subframe. When a bit is <NUM>, it indicates that a fourth part of a corresponding subframe is used for downlink transmission; or when a bit is <NUM>, it indicates that the fourth part of the corresponding subframe is used for uplink transmission.

In manner <NUM>, for the access network device <NUM>, the access network device <NUM> sends downlink control information. The downlink control information indicates whether the fourth part corresponding to the first subframe is used for downlink transmission or uplink transmission.

A terminal device <NUM> or an access network device <NUM> transmits information, that is, sends and/or receives information in the serving cell based on the frame structure determined in step S401.

In step S402, the terminal device <NUM> transmits information in the serving cell based on the frame structure determined in step S401. Herein, the information transmission may be all information transmission performed based on the frame structure.

For example, downlink transmission may include PDSCH transmission, physical downlink control channel (Physical Downlink Control CHannel, PDCCH) transmission, physical hybrid automatic repeat request indicator channel (Physical Hybrid-ARQ Indicator Channel, PHICH) transmission, downlink reference signal transmission, and the like.

Uplink transmission may include PUSCH transmission, PUCCH transmission, uplink reference signal transmission, and the like. Generally, PDSCH-related transmission and the PUSCH transmission may be performed according to specific hybrid automatic repeat request timing (HARQ timing).

For example, when the first subframe in step S401 is the same as that described in example <NUM>, for the terminal device <NUM>, step S402 may be specifically as follows:
The terminal device <NUM> receives downlink control in the first part of the first subframe, and sends uplink control information and/or an SRS in the third part; and when the fourth part is a symbol used for downlink transmission, the terminal device <NUM> receives a PDSCH in the fourth part; or when the fourth part is a symbol used for uplink transmission, the terminal device <NUM> sends a physical uplink shared channel in the fourth part.

For the access network device <NUM>, step S402 may be specifically as follows:
The access network device <NUM> sends downlink control in the first part of the first subframe, and receives uplink control information and/or an SRS in the third part; and when the fourth part is a symbol used for downlink transmission, the access network device <NUM> sends a PDSCH in the fourth part; or when the fourth part is a symbol used for uplink transmission, the access network device <NUM> receives a physical uplink shared channel in the fourth part.

Principles of sending and receiving information by the access network device <NUM> and the terminal device <NUM> in another example of the first subframe are similar to those in example <NUM>.

The following specifically analyzes an impact exerted on information transmission when the frame structure of the first subframe is used.

The first subframe includes a third part, and the third part is used for uplink control information transmission. Therefore, in a wireless communications system using a TDD duplex manner, a HARQ-ACK can also be fed back in a subframe used for downlink transmission (for example, the fourth part is also used for downlink transmission), so as to reduce a HARQ RTT delay, and reduce the user plane delay. In addition, because the HARQ-ACK can be quickly fed back, a scheduling algorithm can be adjusted in the system according to the feedback HARQ-ACK, so as to improve spectrum efficiency.

In addition, because of the introduction of the first subframe, the first subframe may be used to feed back a HARQ-ACK as well as mainly used for downlink transmission, so that different uplink-downlink configurations may be corresponding to same HARQ-ACK timing.

An uplink-downlink configuration <NUM> listed in table <NUM> is used as an example. In this case, a frame structure in a current TDD LTE system and a new frame structure obtained after the first subframe (S1) is introduced may be shown in <FIG>.

It can be learned from <FIG> that in the new frame structure, a HARQ-ACK corresponding to a PDSCH transmitted in a subframe n may be fed back in a subframe n+<NUM>. This is similar to an FDD LTE system. However, in the current TDD LTE system, a HARQ-ACK corresponding to a PDSCH transmitted in a downlink subframe n-k is to be fed back in an uplink subframe n, where k belongs to a set K, and a definition of the set K is shown in table <NUM>. It can be learned from table <NUM> that when the uplink-downlink configuration is <NUM>, values of three elements in the set K are greater than <NUM>. However, in the new frame structure, k values corresponding to all downlink subframes are <NUM>. Therefore, a HARQ RTT delay is reduced when the new frame structure is used.

In addition, in the new frame structure, a subframe used for downlink transmission can also be used to feed back a HARQ-ACK. Therefore, unified HARQ-ACK timing can be used in any uplink-downlink configuration.

In addition, the first subframe is introduced to perform short transmission time interval data transmission in the first part and/or the fourth part of the first subframe. The short TTI data transmission can reduce a user plane delay. Therefore, a low delay can be provided by introducing the first subframe.

In addition, optionally, the fourth part of the first subframe may be half-statically configured for uplink transmission or downlink transmission. In this case, in order that an uplink delay and a downlink delay of a system using a TDD duplex manner can be similar to those of a system using an FDD duplex manner, a frame structure of the system using the TDD duplex manner may use a structure shown in <FIG> (it is assumed that a length of one TTI is a length of a half subframe).

In the frame structure shown in <FIG>, the uplink delay and the downlink delay (obtained when a HARQ RTT delay is not considered and when it is assumed that a length of one subframe is <NUM>) are shown in Table <NUM>. The delay is more close to that in the system using the FDD duplex manner, for example, a delay of an FDD LTE system is <NUM>.

A low delay may be implemented by using the frame structure shown in <FIG>. Further, in order to better match an actual uplink-downlink service ratio, optionally, whether the fourth part of the first subframe is used for uplink transmission or downlink transmission may be dynamically determined. For example, the fourth part is dynamically changed into a symbol used for downlink transmission or dynamically changed into a symbol used for uplink transmission according to uplink and downlink service volumes and a service volume of low delay services. Therefore, a low delay service can be provided without limiting an uplink-downlink configuration of the frame structure, so as to better match real-time uplink and downlink service volumes.

Optionally, the first subframe further includes:
a fourth part: a symbol used for downlink transmission or a symbol used for uplink transmission.

Optionally, the first part includes five symbols, a length of the guard period GP is one symbol, the third part includes one symbol, and the fourth part includes five symbols.

Optionally, the fourth part is located in a tail of the first subframe, or the third part is located in a tail of the first subframe.

Optionally, the apparatus is located in a terminal device, and the processing module <NUM> is specifically configured to:
if uplink grant information corresponding to the fourth part is detected, determine that the fourth part is a symbol used for uplink transmission; or if uplink grant information corresponding to the fourth part is not detected, determine that the fourth part is a symbol used for downlink transmission.

A wireless communications system including the apparatus may be the wireless communications system shown in <FIG>, and a duplex manner of the wireless communications system including the apparatus may be a TDD duplex manner, for example, a TDD LTE system, a TD-SCDMA system, various subsequent evolved wireless communications systems using the TDD duplex manner, and the like. This means that the apparatus may perform communication in the TDD duplex manner, and a communications standard may include a communications standard of any TDD wireless communications system described above.

The wireless communications system including the apparatus may be a single-carrier wireless communications system or a multi-carrier wireless communications system. This means that the apparatus may perform single-carrier communication or multi-carrier communication.

A communications device including the apparatus may be a terminal device <NUM> or an access network device <NUM>. For various communication and processing manners thereof, refer to communication and processing manners of the foregoing terminal device <NUM> and the access network device <NUM>.

For a procedure in which the apparatus sends and receives information, refer to <FIG> and related description. The processing module <NUM> may implement operations such as processing and control in the procedure, and the transceiver module <NUM> may implement operations such as information transmission in the procedure.

The subframe structure, determined by the processing module <NUM>, of the first subframe may be any one of example <NUM> to example <NUM> in the foregoing. The processing module <NUM> may also determine, in the foregoing manner <NUM> or manner <NUM>, whether the fourth part is used for uplink transmission or downlink transmission.

When the apparatus performs information transmission by using the frame structure of the first subframe, for an impact exerted on the information transmission, refer to the foregoing <FIG>, table <NUM>, and related description.

For another optional implementation of the apparatus, refer to the wireless communications system shown in <FIG> and corresponding description.

Optionally, the processing module <NUM> may be implemented by one or more processors. The transceiver module <NUM> may be implemented by one or more transceivers, or be implemented by one or more receivers and one or more transmitters.

The processor for implementing the processing module <NUM> and the transceiver for implementing the transceiver module <NUM>, or the receiver and the transmitter may be integrated into one chip or multiple chips.

<FIG> is a schematic structural diagram of a communications apparatus according to an embodiment. As shown in <FIG>, the communications apparatus includes a processor <NUM> and a transceiver <NUM>.

The processor <NUM> is configured to determine a frame structure of a serving cell.

The transceiver <NUM> is configured to send and receive information in the serving cell according to the frame structure, determined by the processor <NUM>, of the serving cell.

For various optional implementations of the processor <NUM>, refer to those of the processing module <NUM>. For various optional implementations of the transceiver <NUM>, refer to those of the transceiver module <NUM>.

In an embodiment, a communications device is provided, and the communications device may include the apparatus shown in <FIG>. The communications device may be a terminal device or an access network device. For various optional implementations of the communications device, refer to those of the apparatus shown in <FIG>.

<FIG> is a flowchart of an information sending and receiving method according to an embodiment.

S1301: A communications device determines a frame structure of a serving cell.

Optionally, the fourth part is located in a tail of the first subframe or the third part is located in a tail of the first subframe.

Optionally, that a communications device determines a frame structure of a serving cell in step S1301 includes:
if the communications device detects uplink grant information corresponding to the fourth part, determining that the fourth part is a symbol used for uplink transmission; or if the communications device does not detect uplink grant information corresponding to the fourth part, determining that the fourth part is a symbol used for downlink transmission.

In this method, information sending and receiving may be performed in a TDD duplex manner, and a communications standard may include but is not limited to a communications standard used in a TDD LTE system, a TD-SCDMA system, various subsequent evolved wireless communications systems using the TDD duplex manner, and the like.

In this method, during information sending and receiving, communication may be performed based on a single-carrier manner or a multi-carrier manner.

In this method, the communications device may be a terminal device <NUM> or an access network device <NUM>. For various communication and processing manners of the two types of communications devices, refer to communication and processing manners of the foregoing terminal device <NUM> and the access network device <NUM>.

In this method, for a procedure of the information sending and receiving, refer to <FIG> and related description.

In this method, the subframe structure, determined in step S1301, of the first subframe may be any one of example <NUM> to example <NUM> in the foregoing. Whether the fourth part is used for uplink transmission or downlink transmission may be determined in manner <NUM> or manner <NUM> in the foregoing.

When information transmission is performed by using the frame structure of the first subframe, for an impact exerted on the information transmission, refer to the foregoing <FIG>, table <NUM>, and related description.

For another optional implementation of this method, refer to processing and information transmission of the communications device in the wireless communications system shown in <FIG>.

In conclusion, the first subframe including the third part used for uplink control information transmission is introduced into a TDD frame structure, so that uplink control information can also be fed back in a subframe used for downlink transmission in the system. Therefore, the problem that a data transmission delay is relatively long because uplink control information is not fed back in a timely manner can be resolved, so as to reduce a user plane delay. In addition, because uplink control information can be quickly fed back, scheduling can be performed in a system in a timely manner according to the feedback uplink control information, and spectrum efficiency of the system is improved.

Further, the first subframe further includes a fourth part. The fourth part is a symbol used for downlink transmission or a symbol used for uplink transmission.

Persons skilled in the art should understand that the embodiments of the present invention may be provided as a method, a system, or a computer program product. Therefore, the present invention may use a form of hardware only embodiments, software only embodiments, or embodiments with a combination of software and hardware. Moreover, the present invention may use a form of a computer program product that is implemented on one or more computer-usable storage media (including but not limited to a disk memory, a CD-ROM, an optical memory, and the like) that include computer-usable program code.

The present invention is described with reference to the flowcharts and/or block diagrams of the method, the device (system), and the computer program product according to the embodiments of the present invention. It should be understood that computer program instructions may be used to implement each process and/or each block in the flowcharts and/or the block diagrams and a combination of a process and/or a block in the flowcharts and/or the block diagrams. These computer program instructions may be provided for a general-purpose computer, a dedicated computer, an embedded processor, or a processor of any other programmable data processing device to generate a machine, so that the instructions executed by a computer or a processor of any other programmable data processing device generate an apparatus for implementing a specific function in one or more processes in the flowcharts and/or in one or more blocks in the block diagrams.

Claim 1:
A communications apparatus for a time division duplexing long term evolution, TDD LTE, system, comprising:
a processing module (<NUM>), configured to determine a frame structure of a serving cell, wherein
in the determined frame structure of the serving cell, one radio frame comprises at least one first subframe, and the first subframe comprises:
a first part comprising a symbol used for downlink transmission;
a second part that is a guard period, GP;
a third part that is a symbol used for uplink transmission, wherein the uplink transmission comprises uplink control information transmission; and
a fourth part comprising a symbol used for downlink transmission or a symbol used for uplink transmission; and
a transceiver module (<NUM>), configured to send and receive information in the serving cell according to the frame structure, determined by the processing module, of the serving cell;
characterized in that
the fourth part is located in a tail of the first subframe, wherein
the first part is a symbol used for downlink control transmission and downlink data transmission;
the third part is a symbol used for uplink control information transmission and/or sounding reference signal SRS transmission; and
the fourth part is specifically a symbol used for downlink data transmission or a symbol used for uplink data transmission.