CN103444096B - A kind of transmission method controlling signaling and device - Google Patents

Abstract

Embodiments of the present invention provide a method and device for transmitting control signaling, the method comprising: a base station sends control signaling transmission location indication information to a mobile station configured in an open-loop multi-antenna mode; if the control signaling transmits If the sending location of the control signaling indicated by the location indication information is located in the data area, the base station sends the control signaling in the data area by using an open-loop multi-antenna or transmit diversity mode. Through the method and device of the embodiment of the present invention, when the number of mobile stations that need to be scheduled in a cell increases, resulting in an increase in the scheduling information that needs to be sent in a subframe, the control of the mobile station that is configured as an open-loop multi-antenna transmission mode Signaling is transmitted in the data area, which increases user scheduling, thereby improving system throughput and solving the problem of limited PDCCH capacity.

Description

A transmission method and device for control signaling

technical field

The present invention relates to the communication field, in particular to a control signaling transmission method and device.

Background technique

In a Long Term Evolution (LTE, Long Term Evolution) system, a physical downlink control channel (PDCCH, physical downlink control channel) is used to transmit control information, including downlink scheduling information (DL-Grant), uplink scheduling information (UL-Grant), power control information, etc. The specific signaling transmitted in the PDCCH is called downlink control information (DCI, downlink control information). The base station multiplexes the PDCCHs of all mobile stations in the cell and sends them in the first few OFDM symbols of a subframe, and the latter OFDM symbols are used to send the PDSCHs of the mobile stations. The area where the PDCCH is sent is called the control area. The area of the PDSCH is called a data area. Currently, a maximum of 3 OFDM symbols can be used to transmit the PDCCH, and a typical subframe structure is shown in FIG. 1 .

However, in some scenarios, the capacity of the PDCCH may be limited, that is, the capacity of 3 OFDM symbols cannot meet the current mobile station scheduling requirements. In this scenario, as in LTE release 11, multiple radio remote headers (RRH, radio remote headers) exist in a cell at the same time, and the RRH can be deployed in the hotspot area of the cell or at the edge of the cell, so as to provide mobile stations in such areas provide better service. A typical deployment of a cell including RRH is shown in Figure 2 . Since the transmission power of RRHs is low and the RRHs are far apart, mobile stations within the coverage of different RRHs can share the same resources, that is, in a subframe resource, the resources that can be scheduled in a cell The number of mobile stations may increase greatly, so the scheduling information that needs to be sent in one subframe will also increase accordingly, and the traditional 3 OFDM symbols may not be enough to accommodate the scheduling information of all mobile stations. If this problem cannot be solved, the scheduling of users will be reduced, thereby reducing the throughput of the system.

It should be noted that the above introduction of the technical background is only for the convenience of a clear and complete description of the technical solution of the present invention, and for the convenience of understanding by those skilled in the art. It cannot be considered that the above technical solutions are known to those skilled in the art just because these solutions are described in the background of the present invention.

Contents of the invention

The purpose of the embodiments of the present invention is to provide a control signaling transmission method and device, by transmitting the control signaling of the mobile station configured in the open-loop multi-antenna transmission mode in the data area to solve the problem of limited PDCCH capacity .

According to an aspect of an embodiment of the present invention, a method for transmitting control signaling is provided, the method including:

The base station sends control signaling to the mobile station configured in the open-loop multi-antenna mode to send location indication information;

If the sending location of the control signaling indicated by the control signaling sending location indication information is located in the data area, the base station sends the control signaling in the data area in an open-loop multi-antenna or transmit diversity manner.

According to another aspect of the embodiments of the present invention, a base station is also provided, and the base station includes:

A first sending unit, which sends control signaling to a mobile station configured in an open-loop multi-antenna manner to send location indication information;

The second sending unit, when the sending position of the control signaling indicated by the control signaling sending position indication information sent by the first sending unit is located in the data area, it uses an open-loop multi-antenna or transmit diversity method to transmit the data in the data area The area sends the control signaling.

According to another aspect of the embodiments of the present invention, there is also provided a computer-readable program, wherein, when the program is executed in a base station, the program causes a computer to execute the aforementioned control signaling transmission method in the base station.

According to another aspect of the embodiments of the present invention, there is also provided a storage medium storing a computer-readable program, wherein the computer-readable program enables the computer to execute the control described in any one of claims 1-7 in the base station Signaling transmission method.

The beneficial effect of the embodiment of the present invention is that: when the number of mobile stations that need to be scheduled in a cell increases, resulting in an increase in the scheduling information that needs to be sent in a subframe, the method and device in the embodiment of the present invention will be configured as an open-loop The control signaling of the mobile station in the multi-antenna transmission mode is transmitted in the data area, which increases user scheduling, thereby improving the throughput of the system and solving the problem of limited PDCCH capacity.

With reference to the following description and accompanying drawings, there are disclosed in detail specific embodiments of the invention, indicating the manner in which the principles of the invention may be employed. It should be understood that embodiments of the invention are not limited thereby in scope. Embodiments of the invention encompass many changes, modifications and equivalents within the spirit and scope of the appended claims.

Features described and/or illustrated with respect to one embodiment can be used in the same or similar manner in one or more other embodiments, in combination with, or instead of features in other embodiments .

It should be emphasized that the term "comprising/comprising" when used herein refers to the presence of a feature, integer, step or component, but does not exclude the presence or addition of one or more other features, integers, steps or components.

Description of drawings

Many aspects of the invention can be better understood with reference to the following figures. The components in the figures are not drawn to scale, merely illustrating the principles of the invention. In order to facilitate illustration and description of some parts of the present invention, corresponding parts in the drawings may be exaggerated or reduced. Elements and features described in one drawing or one embodiment of the present invention may be combined with elements and features shown in one or more other drawings or embodiments. Furthermore, in the drawings, like numerals indicate corresponding parts in the several figures and may be used to indicate corresponding parts used in more than one embodiment. In the attached picture:

FIG. 1 is a schematic diagram of a typical subframe structure;

FIG. 2 is a schematic diagram of a cell network structure including RRH;

FIG. 3 is a flowchart of a control signaling transmission method provided in Embodiment 1 of the present invention;

Fig. 4 is a processing flowchart of sending control signaling in the data area in the TxD manner;

Fig. 5 is a flow chart of the sending end processing of the closed-loop/open-loop MIMO transmission mode in the current standard;

FIG. 6 is a flow chart of sending end processing when open-loop MIMO adopts a rank number of 1 in a future LTE system;

Fig. 7 is a flow chart of precoding processing in the open-loop MIMO transmission mode in the current standard;

FIG. 8 is a processing flow chart of a sending end for sending control signaling in a data area by using an open-loop MIMO method according to an embodiment of the present invention;

FIG. 9 is a schematic diagram of the composition of a base station provided by Embodiment 2 of the present invention.

detailed description

The foregoing and other features of embodiments of the present invention will become apparent from the following description, with reference to the accompanying drawings. These embodiments are illustrative only, and do not limit the present invention. In order to enable those skilled in the art to easily understand the principle and implementation of the present invention, the implementation of the present invention will be described by taking the transmission method of control signaling in the following LTE/LTE-A system as an example, but it can be understood that this The embodiments of the present invention are not limited to the above systems, and the embodiments of the present invention are applicable to any system involving the transmission of control signaling.

An embodiment of the present invention provides a control signaling transmission method, as described in Embodiment 1 below.

Example 1

FIG. 3 is a flowchart of a control signaling transmission method provided by Embodiment 1 of the present invention. Referring to Figure 3, the method includes:

Step 301: the base station sends a control signaling to a mobile station configured in an open-loop multi-antenna (MIMO) mode to send location indication information;

Wherein, the control signaling transmission position indication information is used to indicate the transmission position of the control signaling, where the transmission position may be in the control area, that is, the traditional PDCCH area, or in the data area, that is, the traditional PDSCH area.

Step 302: If the transmission position of the control signaling indicated by the control signaling transmission position indication information is located in the data area, the base station adopts open-loop multi-antenna (MIMO, Multiple Input Multiple Output) or transmit diversity (TxD, transmit diversity) to send the control signaling in the data area.

This embodiment provides a control signaling transmission method for a mobile station configured in the open-loop MIMO mode, changing the control signaling from the transmitted PDCCH region to the data region, and the transmission method can be an open-loop MIMO method , TxD mode can also be used.

When the control signaling is sent in the data area in the TxD manner, the sending procedure of the control signaling is the same as that in the TxD manner in the existing standard. Taking two antennas at the sending end as an example, the typical processing process is shown in Figure 4. The sending end only uses one set of modulation and coding links, that is, there is only one codeword (codeword). Source bit information, for example, the control signaling of this embodiment is channel coded and symbol modulated, and then layer mapping is performed on the generated symbols, and the number of branches (layers) after layer mapping is called rank number (rank), as shown in FIG. 4 rank=2, the layer-mapped data is precoded, and the generated symbol sequence is mapped to the allocated resource element, and finally sent out through the antenna. where the pre-encoded input symbol is a vector $\left[\begin{array}{c}{x}_1\\ x_2\end{array}\right],$ The output symbol is a matrix $\left[\begin{array}{cc}{x}_1& x_2^{*}\\ x_2& -x_1^{*}\end{array}\right].$

When the open-loop MIMO method is used to send control signaling in the data area, the modulation and coding method of the control signaling is the same as the modulation and coding method of the open-loop MIMO method in the existing standard, but the layer mapping and precoding method of the control signaling It is different from the way of layer mapping and encoding in existing standards. In order to make the method of sending control signaling in the data area using the open-loop MIMO method in this embodiment clearer and easier to understand, the method of using the open-loop MIMO method in the existing standard to send data in the data area is compared with the method used in the embodiment of the present invention below. The open-loop MIMO mode sends control signaling in the data area for detailed description.

FIG. 5 is a schematic diagram of a processing flow for sending data in a data area in an open-loop/closed-loop MIMO manner in an existing standard, please refer to FIG. 5 . A base station configured with multiple antennas has two main transmission modes, one is an open-loop multiple-antenna mode, and the other is a closed-loop multiple-antenna mode. Among them, the open-loop multi-antenna mode is mainly configured for mobile stations with relatively high moving speeds. The precoding matrix used by the base station does not require feedback from the mobile station, and the base station specifies the precoding matrix through certain rules; the closed-loop multi-antenna mode is for mobile stations. The mobile station with relatively low speed is configured, and the precoding matrix used by the base station is mainly obtained according to the precoding matrix index (PMI, precoding matrix index) fed back by the mobile station, and then corresponds to a commonly predetermined codebook (codebook).

In existing standards, the transmitter models of the open-loop multi-antenna mode and the closed-loop multi-antenna mode are similar. Taking the transmission mode with two antennas and rank=2 as an example, the transmission process at the transmission end is shown in FIG. 5 . Comparing Figure 4 and Figure 5, it can be seen that one difference between the open-loop/closed-loop multi-antenna transmission mode and the TxD transmission mode is that the number of links corresponding to the modulation and coding of the transmitting end is different when the configuration is rank>=2. For the TxD transmission mode, the number of modulation and coding links at the sending end is 1; for the open-loop/closed-loop multi-antenna transmission mode, when rank>=2, the number of modulation and coding links at the sending end is 2.

In the existing standard, if the mobile station configured in the open-loop MIMO transmission mode really adopts the open-loop MIMO transmission mode, the lowest rank=2, and the lowest rank=1 available for closed-loop MIMO. For the mobile station in the open-loop MIMO transmission mode, if the rank=2 cannot meet the requirements of the current channel, it can fall back to the transmit diversity transmission mode. In addition, in the future LTE system, the open-loop MIMO transmission mode may also support the lowest rank=1 mode, and the model of the transmission end at this time is shown in FIG. 6 .

In the existing standard, the transmitting end of the open-loop MIMO can be expressed as: y=W×D×U×x, that is, the precoding matrix includes three parts, namely matrix W, matrix D and matrix U. Taking two antennas and rank=2 as an example, the process of sending a signal through matrix D and matrix U is shown in FIG. 7 . It can be seen that before passing through the matrix W, each symbol on each layer contains signals from codeword 1 (codeword1) and codeword 2 (codeword2), that is, a diversity effect is achieved. If there is no such diversity effect, that is, the transmitted signal directly passes through the matrix W instead of the matrix D and the matrix U, then when the channel condition on a certain layer suddenly deteriorates, the codeword (codeword) mapped to this layer will be affected. Decoding has a very adverse effect. In existing standards, the precoding matrix of closed-loop MIMO only includes a matrix W'.

FIG. 8 is a schematic diagram of a processing flow for sending control signaling in the data area by using an open-loop MIMO method according to an embodiment of the present invention. In this embodiment, rank=2 and four transmitting antennas are used as an example. Please refer to FIG. 8 .

In an embodiment, when the base station uses an open-loop multi-antenna method to send control signaling in the data area, the rank number used by the base station to send the control signaling may be the lowest rank of the supported open-loop multi-antenna method. number. That is, if the supported open-loop multi-antenna mode is the existing standard open-loop MIMO mode, the rank number used for sending the control signaling in this embodiment is rank=2, if the supported open-loop multi-antenna mode The mode is the newly defined open-loop MIMO mode, and the new mode supports rank=1, then the rank number used for sending the control signaling in this embodiment is rank=1.

In another embodiment, when the base station uses an open-loop multi-antenna method to send control signaling in the data area, the rank number used by the base station to send the control signaling may also be the rank number configured by the base station for sending data . That is, the rank value used by the control signaling in this embodiment may also be equal to the rank value configured by the base station for data. For example, if the base station configures rank=2 for data, rank=2 is used in the control signaling of this embodiment; if rank=3 is configured for data at the base station, then rank=3 is used for the control signaling of this embodiment; If the base station configures rank=4 for data, the control signaling in this embodiment adopts rank=4. and so on.

In this embodiment, when the rank number used by the base station to send the control signaling in the data area is greater than or equal to 2, different from the existing standard (that is, FIG. 5 ), the base station uses a modulation and coding link to send the Control signaling. Please refer to Figure 8, firstly, channel coding is performed on the control signaling; then, the channel coded symbols are modulated; after that, layer mapping is performed on the modulated symbols according to the rank number; finally, a single pre- The coding matrix precodes the layer-mapped data.

As shown in FIG. 8, in this embodiment, the precoding (precoding) process only uses a single precoding matrix W, and does not include matrix D and matrix U. This is because only one codeword (codeword) is used, And the corresponding modulated signal is allocated to two branches (layers), which has achieved the effect of diversity.

In this embodiment, if the mobile station is configured as an open-loop MIMO transmission mode, and its demodulation of data is configured to perform channel estimation based on a dedicated pilot, then the data region and the corresponding data transmitted in the same subframe Control signaling also performs channel estimation through dedicated pilots, and then demodulates.

In this embodiment, since the data is also transmitted in the open-loop MIMO mode, as described above, based on the channel requirements, the open-loop MIMO transmission mode of the data may fall back to the transmit diversity transmission mode. Therefore, according to this embodiment In the method, when it is found that the open-loop MIMO transmission mode of data falls back to the transmission mode of transmit diversity, the control signaling also falls back to the transmission mode of transmit diversity. Specifically, when the base station uses an open-loop multi-antenna method to send the control signaling in the data area, this embodiment can also determine whether the base station falls back to sending data in transmit diversity mode, and if the base station falls back to When the data is sent in the transmit diversity mode, the base station also falls back to transmit the control signaling in the transmit diversity mode.

Through the method of the embodiment of the present invention, when the number of mobile stations that need to be scheduled in a cell increases, resulting in an increase in the scheduling information that needs to be sent in a subframe, the control signaling of the mobile station configured as the open-loop multi-antenna transmission mode Putting it in the data area for transmission increases user scheduling, thereby improving system throughput and solving the problem of limited PDCCH capacity.

An embodiment of the present invention also provides a base station, as described in Embodiment 2 below. Since the principle of the base station to solve the problem is similar to the method for transmitting control signaling based on the base station in Embodiment 1 above, the implementation of the base station can refer to the implementation of the method, and the repetition will not be repeated.

FIG. 9 is a schematic composition diagram of a base station provided by an embodiment of the present invention. Please refer to Figure 9, the base station includes:

The first sending unit 91, which sends control signaling to the mobile station configured in the open-loop multi-antenna mode to send location indication information;

The second sending unit 92, when the sending position of the control signaling indicated by the control signaling sending position indication information sent by the first sending unit 91 is located in the data area, it adopts an open-loop multi-antenna or transmit diversity method in the Send the control signaling in the data area.

It can be seen from Embodiment 1 that the base station of this embodiment provides a method for transmitting control signaling for mobile stations configured in an open-loop MIMO mode, by changing the transmission of control signaling from the PDCCH region to the data region. The transmission method may adopt an open-loop MIMO method or a TxD method. This solves the problem that the PDCCH capacity is limited for mobile stations configured in the open-loop MIMO mode.

In one embodiment, when the second sending unit 92 sends the control signaling in the data area in an open-loop multi-antenna manner, the method used by the second sending unit 92 to send the control signaling The rank number is: the lowest rank number of the open-loop multi-antenna mode that can be supported.

In another embodiment, when the second sending unit 92 uses an open-loop multi-antenna method to send the control signaling in the data area, the method used by the second sending unit 92 to send the control signaling The rank number of is: the rank number configured by the base station for sending data.

Wherein, if the rank number used by the second sending unit 92 to send the control signaling is greater than or equal to 2, the second sending unit 92 uses one modulation and coding link to send the control signaling. Wherein, the second sending unit 92 includes:

a channel coding module 921, which performs channel coding on the control signaling;

a modulation module 922, which modulates the channel-coded symbols;

A layer mapping module 923, which performs layer mapping on the modulated symbols according to the rank number;

A precoding module 924, which uses a single precoding matrix to precode layer-mapped data.

In this embodiment, the control signaling sent by the second sending unit 92 in the data area uses a dedicated pilot to perform channel estimation for demodulation.

In this embodiment, when the base station sends the control signaling in the data area in an open-loop multi-antenna manner, the base station further includes:

A judging unit 93, which judges whether the base station falls back to sending data in a transmit diversity mode;

The second sending unit 92 falls back to sending the control signaling in a transmit diversity mode when the judging unit 93 judges yes.

Through the base station in the embodiment of the present invention, when the number of mobile stations that need to be scheduled in a cell increases, resulting in an increase in the scheduling information that needs to be sent in a subframe, the base station will be configured as the control of the mobile station in the open-loop multi-antenna transmission mode Signaling is transmitted in the data area, which increases user scheduling, thereby improving system throughput and solving the problem of limited PDCCH capacity.

An embodiment of the present invention also provides a computer-readable program, wherein when the program is executed in a base station, the program causes a computer to execute the control signaling transmission method described in Embodiment 1 in the base station.

An embodiment of the present invention also provides a storage medium storing a computer-readable program, wherein the computer-readable program enables a computer to execute the control signaling transmission method described in Embodiment 1 in a base station.

The above devices and methods of the present invention can be implemented by hardware, or by combining hardware and software. The present invention relates to such a computer-readable program that, when the program is executed by a logic component, enables the logic component to realize the above-mentioned device or constituent component, or enables the logic component to realize the above-mentioned various methods or steps. Logic components such as field programmable logic components, microprocessors, processors used in computers, and the like. The present invention also relates to a storage medium for storing the above program, such as hard disk, magnetic disk, optical disk, DVD, flash memory and the like.

The present invention has been described above in conjunction with specific embodiments, but those skilled in the art should be clear that these descriptions are all exemplary and not limiting the protection scope of the present invention. Those skilled in the art can make various variations and modifications to the present invention according to the spirit and principle of the present invention, and these variations and modifications are also within the scope of the present invention.

Claims (12)

1. A method for transmitting control signaling, wherein the method comprises: The base station sends the indication information of the sending position of the control signaling to the mobile station; If the mobile station is configured in the open-loop multi-antenna mode, and the sending position of the control signaling indicated by the indication information of the sending position of the control signaling is located in the data area, the base station adopts the open-loop multi-antenna mode or sends sending the control signaling in the data area in a diversity manner; Wherein, when the base station uses an open-loop multi-antenna method to send the control signaling in the data area, the rank number used by the base station to send the control signaling is: Supportable open-loop multi-antenna method the lowest rank of . 2. A method for transmitting control signaling, wherein the method comprises: The base station sends the indication information of the sending position of the control signaling to the mobile station; If the mobile station is configured in the open-loop multi-antenna mode, and the sending position of the control signaling indicated by the indication information of the sending position of the control signaling is located in the data area, the base station adopts the open-loop multi-antenna mode or sends sending the control signaling in the data area in a diversity manner; Wherein, when the base station transmits the control signaling in the data area in an open-loop multi-antenna manner, the rank number used by the base station to transmit the control signaling is: rank number. 3. The method according to claim 1 or 2, wherein, if the rank number used by the base station to send the control signaling is greater than or equal to 2, the base station uses one modulation and coding link to send the control signaling . 4. The method according to claim 3, wherein the base station sends the control signaling using a modulation and coding link, comprising: performing channel coding on the control signaling; modulating the channel-coded symbols; performing layer mapping on the modulated symbols according to the rank number; A single precoding matrix is used to precode layer-mapped data. 5. The method according to claim 1 or 2, wherein the control signaling sent in the data area performs channel estimation through a dedicated pilot. 6. The method according to claim 1 or 2, wherein, when the base station sends the control signaling in the data area in an open-loop multi-antenna manner, the method further comprises: judging whether the base station falls back to sending data in a transmit diversity mode; If the base station falls back to sending data in a transmit diversity mode, the base station falls back to sending the control signaling in a transmit diversity mode. 7. A base station, wherein the base station comprises: a first sending unit, which sends the indication information of the sending position of the control signaling to the mobile station; The second sending unit is configured in the mobile station in an open-loop multi-antenna mode, and the sending position of the control signaling indicated by the indication information of the sending position of the control signaling sent by the first sending unit is located in the data area , sending the control signaling in the data region by using open-loop multi-antenna or transmit diversity; Wherein, when the second sending unit sends the control signaling in the data area in an open-loop multi-antenna manner, the number of ranks used by the second sending unit to send the control signaling is: supportable The lowest rank of the open-loop multi-antenna approach. 8. A base station, wherein the base station comprises: a first sending unit, which sends the indication information of the sending position of the control signaling to the mobile station; The second sending unit is configured in the mobile station in an open-loop multi-antenna mode, and the sending position of the control signaling indicated by the indication information of the sending position of the control signaling sent by the first sending unit is located in the data area , sending the control signaling in the data region by using open-loop multi-antenna or transmit diversity; Wherein, when the second sending unit sends the control signaling in the data area in an open-loop multi-antenna manner, the rank number used by the second sending unit to send the control signaling is: the The rank configured by the base station for sending data. 9. The base station according to claim 7 or 8, wherein, if the rank number used by the second sending unit to send the control signaling is greater than or equal to 2, the second sending unit uses a modulation and coding link Send the control signaling. 10. The base station according to claim 9, wherein the second sending unit comprises: a channel coding module, which performs channel coding on the control signaling; a modulation module, which modulates the channel-coded symbols; A layer mapping module, which performs layer mapping on the modulated symbols according to the rank number; The precoding module uses a single precoding matrix to precode layer-mapped data. 11. The base station according to claim 7 or 8, wherein the control signaling sent by the second sending unit in the data region is to perform channel estimation through a dedicated pilot. 12. The base station according to claim 7 or 8, wherein when the base station transmits the control signaling in the data area in an open-loop multi-antenna manner, the base station further comprises: A judging unit, which judges whether the base station falls back to sending data in a transmit diversity mode; The second sending unit falls back to sending the control signaling in a transmit diversity mode when the judging unit judges yes.