WO2009152737A1

WO2009152737A1 - Method and system of reporting channel information in time division duplex system

Info

Publication number: WO2009152737A1
Application number: PCT/CN2009/072203
Authority: WO
Inventors: 潘学明; 喻晓冬; 肖国军; 丁昱; 索士强
Original assignee: 大唐移动通信设备有限公司
Priority date: 2008-06-20
Filing date: 2009-06-10
Publication date: 2009-12-23
Also published as: CN101610523A; CN101610523B

Abstract

A method and system of reporting channel information in TDD system are provided by the present invention, the method includes: a base station sends a RRC signaling to an UE to indicate the periodic sub-frame offset position configuration of the channel information reported in the Physical Uplink Control Channel (PUCCH) by UE; the RRC signaling comprises: the periodic sub-frame offset position parameter of the wideband Channel Quality Information (CQI) or Pre-coding Matrix Indicator (PMI) reported periodically in PUCCH, and the periodic sub-frame offset position parameter of the sub-band CQI or PMI reported periodically in PUCCH, and the periodic sub-frame offset position parameter of the Rank Indicator (RI) reported periodically in PUCCH; the length of the parameter is determined by the TDD frame structure configuration in such way: determining the possibility number of the periodic sub-frame offset position according to the TDD frame structure configuration, then determining the length of the parameter, and performing the report in PUCCH at UE according to the configuration. The present invention can save the signaling spending in TDD system and make the switch information spending in TDD system more close to FDD system, and the compatibility of two systems is improved.

Description

Method and system for reporting channel information in time division duplex system

Technical field

The present invention relates to the field of time division duplex (TDD) systems, and in particular, to a method and system for reporting channel information in a TDD system. Background of the invention

The channel information includes a channel quality indicator (CQI), a precoding matrix indication (PMI), and a rank indication (RI), and the base station sends high layer signaling, such as radio resource control (RRC) signaling, to the user equipment (UE), indicating that the UE is in the physical A period of reporting channel information on the uplink control channel (PUCCH) and a periodic subframe offset position configuration. The UE reports the channel information on the PUCCH according to the periodic subframe offset position configuration.

In the prior art, for the frequency division duplex (FDD) mode, each subframe can be used to report channel information, and the period of reporting channel information is 2ms, 5ms, 10ms, 20ms, 40ms, 80ms, and 160ms. For the two different situations, the maximum period is 40ms or 160ms, the RRC signaling sent by the base station to the UE includes two sets of system parameters of different lengths to notify the UE to report channel information. The following are introduced separately:

Referring to Table 1, Table 1 is a list of system parameters for reporting channel information sent by the base station to the UE in the case where the maximum period is 40 ms in the prior art.

Format indicates broadband combined subband reporting

PUCCH Last week 7 Periodically reported broadband CQI/PMI on PUCCH:

Reporting broadband o N _p = 2ms, 5ms, 10ms, 20ms, 40ms, OFF

CQI/PMI (not indicated)

Period (Np) sub-N. _FFSET and N _{p are} missing, N. Li _{Γ =} 0, _1, -2 frame offset - (^ - 1)

( N ); Bit ο Total number of possibilities: 2+5+10+20+40+1=78

PUCCH Last week 7 Periodically report the subband CQI on the PUCCH:

Period report sub-band o N _p = 2ms, 5ms, 10ms, 20ms, 40ms, OFF

Cycle of CQI (represents not reported)

(N _p) subframe about ^ spirit and vinylidene _{^0, N OFFSET = 0, _1,} -2 shift (N); - (^ - 1)

o Total number of possibilities: 2+5+10+20+40+1=78

The PUCCH reports the RI periodically on the PUCCH last week, and provides the periodic information of the RI to report the RI and the subframe offset:

Period sub-frame partial o period information: M _RI = 1, 2, 5, 10, 20, 40, shift position OFF (indicating no report), RI period is _3⁄4 times of CQI or CQI/PMI period

o Subframe offset: Depending on the maximum period (40ms),

The subframe offset (N _0FFSET ) reported by the wideband period on the PUCCH corresponds to the correlation. RI subframe offset 0 = 0, -1, -2

- ( ^ - 1 )

o Total number of possibilities: 7x40 = 280 Table 1

Table 1 is to be explained as follows: As in the third row of Table 1, when N _p = 2ms, N _0FFSET = 0, - 1, that is, there are two kinds of periodic sub-frame offset positions for reporting the wideband CQI/PMI. Possible cases: Reported by subframes 0, 2, 4, 6, and 8, or reported by subframes 1, 3, 5, 7, and 9. When 5ms, N 0 - 1, -2, -3, -4, that is, the periodic sub-frame offset position of the wideband CQI/PMI is reported. There are five possible cases: Subframe 0 and 5 are reported, sub-frame 1 is used. 6 reporting, reporting by subframes 2 and 7, reporting by subframes 3 and 8, or reporting by subframes 4 and 9. And so on, the total number of possibilities is: 2+5+10+20+40+1=78. The 78 possible cases can be represented by a minimum of 7-bit binary parameters. Therefore, the period of the periodic sub-frame offset position parameter of the wide-band CQI/PMI reported on the PUCCH is 7 bits.

Referring to Table 2, Table 2 is a list of system parameters for reporting channel information sent by the base station to the UE in the case where the maximum period is 160 ms in the prior art.

Parameter name Usage Description

Bit

Number

PUCCH last week 1 indicates the following two cases:

Reported CQI broadband report

Format indication broadband combined subband reporting

PUCCH last week 9 reports broadband CQI/PMI on PUCCH:

Period reported broadband o N _p = 2ms, 5ms, 10ms, 20ms, 40ms, 80ms, 160ms of CQI/PMI, OFF (not indicating)

Period ( Np ) ⁰ N _FFSET ^ N _{p is} lost, N _OFFSET =0, -1, -2 subframe offset - N _p - \ )

(N); bit o total number of possibilities: 2+5+ 10+20+40+80+ 160+1=338

Period sub-frame partial o period information: M _R1 = 1, 2, 5, 10, 20, 40, shift position OFF (indicating no report), RI period is _3⁄4 times of CQI or CQI/PMI period

o Subframe offset: Depends on the maximum period (160ms), which is related to the subframe offset (N) reported by the wideband period on the PUCCH. Subframe offset 0 = 0, - 1, - 2 - ( N _p

- 1 )

o Total number of possibilities: 7x160 = 1120

Table 2

The process of the base station notifying the UE to report the channel information is as follows: For example, referring to Table 1, the base station sends the RRC signaling to the UE, where the RRC signaling includes a periodic sub-frame offset position of the cyclically reported wideband CQI/PMI on the PUCCH. "Parameters, indicating that the UE reports the wideband CQI/PMI according to the specified period and location; according to the parameter, the UE may report the broadband CQI/PML other parameters on the PUCCH according to the specified period and location, and notify the UE to report the channel information. This is similar.

For the TDD mode, since not every subframe can be used to report channel information, the period of reporting channel information currently prepared is 5ms, 10ms, 20ms, 40ms, 80ms, and 160ms. For the two different cases where the maximum period is 40ms or 160ms, the system uses the system parameters of Tables 1 and 2 above to notify the UE to report channel information. Since the period and location configuration of the reported channel information in the TDD mode is less likely than in the FDD mode, the required system parameter length is shorter than the system parameter length in the FDD mode. Therefore, using the system parameters of Table 1 and Table 2 will result in waste of signaling overhead of the TDD system. Summary of the invention

The embodiment of the invention provides a method for reporting channel information in a TDD system, which can save signaling overhead of the TDD system.

The embodiment of the present invention provides a system for reporting channel information in a TDD system, which can save signaling overhead of the TDD system.

The technical solution of the present invention is implemented as follows:

A method for reporting channel information in a TDD system includes:

The eNB sends the RRC signaling to the UE, and indicates the period in which the UE reports the channel information on the PUCCH and the periodic subframe offset position configuration.

The RRC signaling includes: a cyclic subframe offset position parameter periodically reporting a wideband CQI or PMI on a PUCCH, a periodic subframe offset position parameter periodically reporting a sub-band CQI or a PMI on a PUCCH, and a period of periodically reporting an RI on a PUCCH a sub-frame offset position parameter; the length of the three parameters is determined by a TDD frame structure configuration, and the determining manner is: determining, according to the TDD frame structure configuration, a probability number of a periodic sub-frame position of the reported channel information, according to the The number of possibilities determines the length of the parameter;

The UE reports channel information on the PUCCH according to the periodic subframe offset position configuration; and a system for uplink channel information in the TDD system, including:

a base station, configured to send RRC signaling to the UE, to indicate a period in which the UE reports channel information on the PUCCH, and a periodic subframe offset position configuration;

The RRC signaling includes: a cyclic subframe offset position parameter periodically reporting a wideband CQI or PMI on a PUCCH, a periodic subframe offset position parameter periodically reporting a sub-band CQI or a PMI on a PUCCH, and a period of periodically reporting an RI on a PUCCH Subframe offset position parameter; the length of the three parameters is determined by a TDD frame structure configuration, and the determined manner is: The TDD frame structure configuration determines a probability number of a periodic subframe offset position of the reported channel information, and determines a length of the parameter according to the number of possibilities;

The UE is configured to report channel information on the PUCCH according to the periodic subframe offset position configuration.

It can be seen that, in the method and system of the embodiment of the present invention, when the base station sends a system parameter for reporting channel information to the UE, the length of the used parameter is shorter than the length of the parameter in the prior art, so that the TDD system can be saved. Signaling overhead. Mode for carrying out the invention

As mentioned above, the current period for reporting channel information in the TDD mode is 5ms, 10ms, 20ms, 40ms, 80ms and 160ms. To clearly explain the position configuration at various cycles, the following describes the frame structure of the TDD mode. Referring to Table 3, Table 3 is a list of frame structures of different configuration types of the TDD mode in the prior art, where "D" represents a downlink subframe, "S" represents a special subframe, and "U" represents an uplink subframe.

table 3

According to Table 3, when the period of reporting channel information is 5ms, there are up to 3 possible In the case of selecting subframes 2 and 7, subframes 3 and 8, or subframes 4 and 9, the channel information is reported; when the period of reporting channel information is 10 ms, there are at most six possible cases, that is, selecting subframes 2 and 3 4, 7, 8, or 9 report channel information; When the period of reporting channel information is 20ms, there are up to 12 possible cases (can be regarded as selecting from 2 10ms frames); when the period of reporting channel information is 40ms There are up to 24 possible cases (can be regarded as selecting from 4 10ms frames); when the period of reporting channel information is 80ms, there are up to 48 possible cases (can be regarded as selecting from 8 10ms frames) When the period of reporting channel information is 160ms, there are up to 96 possible cases (can be regarded as selecting from 16 10ms frames).

It can be seen that, for the TDD mode, the periodic subframe offset position configuration of the reported channel information is less than that of the FDD mode. To be compatible with the existing system, the parameters in Tables 1 and 2 above can still be used as the system for reporting channel information. Parameters, but the length of the parameters used can be reduced. The length of the parameters is determined according to the uplink subframe configuration of the TDD frame structure.

The method for reporting channel information in the TDD system according to the embodiment of the present invention includes: the base station sends RRC signaling to the UE, instructing the UE to report the channel information period on the PUCCH, and the periodic subframe offset position configuration; the UE according to the period Frame offset position configuration, reporting channel information on the PUCCH;

The RRC signaling includes: a cyclic subframe offset position parameter periodically reporting a wideband CQI or PMI on a PUCCH, a periodic subframe offset position parameter periodically reporting a sub-band CQI or a PMI on a PUCCH, and a period of periodically reporting an RI on a PUCCH Subframe offset position parameter; the length of the three parameters is determined by a TDD frame structure configuration, and the determined manner is:

The TDD frame structure configuration determines the number of possible sub-frame partial positions of the reported channel information, and the length of the parameter is determined based on the number of possibilities.

The following specific examples are given:

Embodiment 1:

Referring to Table 4, Table 4 is a base station in the case where the maximum period is 40 ms according to the embodiment of the present invention. A list of system parameters for reporting channel information sent to the UE.

_3⁄4 times the cycle

o Subframe offset: depends on the maximum period (40ms), and

The subframe offset (N _0FFSET ) reported by the wideband period on the PUCCH is correlated.

o Total number of possibilities: 7x24 = 168

Table 4

It can be seen from the above Table 4 that for the TDD mode, in the case where the maximum period is 40 ms, there may be 46 cases of reporting the periodic subframe offset position of the wideband CQI/PMI, so "the cycle of reporting the wideband CQI/PMI on the PUCCH cycle" The frame offset position "parameter length can be reduced to 6 bits; there may be 46 cases of the periodic sub-frame offset position of the sub-band CQI/PMI, so the "period reporting sub-band CQI periodic sub-frame offset position on PUCCH" parameter The length of the periodic sub-frame offset position of the reported RI may be 168. Therefore, the length of the "periodic subframe offset position of the periodic report of RI on PUCCH" parameter can be reduced to 8 bits.

Embodiment 2:

Referring to Table 5, Table 5 is a system parameter list for reporting channel information sent by the base station to the UE in the case where the maximum period is 160 ms in the second embodiment of the present invention.

80ms, 160ms, OFF of CQI/PMI (not indicating)

Period (Np) sub-O ^ ^ is related to ^

Frame offset o Total number of possible possibilities:

( N ); Bit 3+6+12+24+48+96+1=190

o Subframe offset: depends on the maximum period (160ms), and

The subframe offset (N) reported by the wideband period on the PUCCH is correlated.

o Total number of possibilities: 7x96 = 672

table 5

As can be seen from the above Table 5, for the TDD mode, in the case where the maximum period is 160 ms, the "period CQI/PMI periodic subframe offset position on the PUCCH" parameter and the "period subframe offset of the periodic report RI on the PUCCH" The number of bits in the position parameter can be reduced to 8bit and lObito respectively.

In addition, the minimum period of the reported channel information in the TDD mode in the prior art is 5 ms. The embodiment of the present invention also proposes a configuration in which the reporting period is 1 ms and 2 ms, as follows:

(1) The period of reporting the channel information in the TDD mode is 2 ms, which means: Selecting two uplink subframes to report channel information in the previous field of each frame, or respectively in the two frames before and after each frame Select 2 uplink subframes to report channel information, specifically: (1) For the TDD frame structure configuration types 0, 1, and 6, two subframes are respectively selected in the previous two fields for reporting channel information;

(2) For the TDD frame structure configuration types 3 and 4, select 2 subframes in the previous field for reporting channel information;

(3) For the TDD frame structure configuration types 2 and 5, the 2ms period cannot be reported, ignoring this situation.

As shown in Table 6, Table 6 is an example of an uplink subframe list used when the period of reporting channel information is 2 ms.

Table 6

As can be seen from Table 6, for TDD frame structure configuration types 0, 1, and 6, you can select a subframe. 2, 3, 7 and 8 channel information; For TDD frame structure configuration types 3 and 4, subframes 2 and 3 can be selected to report channel information.

For TDD frame structure configuration type 0, subframes 2, 4, 7, and 9, or subframes 3, 4, 8, and 9 may be selected for reporting channel information; for TDD frame structure configuration type 3, subframe 2 may also be selected. And 4, or select subframes 3 and 4 to report channel information. It can be seen that when the period of reporting channel information is 2ms, there are three possible situations for the CQI/PMI period and position configuration.

(2) The period of reporting the channel information in the TDD mode is lms, which means: In a frame, each uplink subframe is used to report channel information, specifically:

(1) For the TDD frame structure configuration types 0, 3, and 6, each uplink subframe is selected for reporting channel information.

(2) For other TDD frame structure configuration types, this situation is ignored because it is the same as other reporting periods.

As shown in Table 7, Table 7 is a list of uplink subframes used when the period of reporting channel information is lms.

5 10ms DS u DDDDDDD

6 10ms D s channel channel channel D S channel channel D

Information information information information information

Table 7

It can be seen from Table 7 that for the TDD frame structure configuration types 0, 3, and 6, all the uplink subframes can be selected for channel information reporting. When the period of reporting channel information is lms, the period and location configuration of the reported channel information is only one of the above possible cases.

When the reporting period proposed by the present invention is increased to the lms and 2 ms configuration, the system parameters in Tables 4 and 5 of the above embodiments can still be employed. For example, as shown in Table 4, the "Period reporting of wideband CQI/PMI on PUCCH" parameter, the total possible time for reporting CXI/PMI on the PUCCH due to the increase of the configuration of the period of lms and 2ms The number of sexes is: 46+1+3 = 50, and all possible cases can still be represented by a 6-bit length parameter. The case of other parameters is similar, and the parameter length is sufficient to indicate all the cases, and will not be described here.

Therefore, in the method provided by the present invention, the period and location configuration may include: a period of 2 ms, and the location is: in the TDD frame structure configuration type 0, 1, or 6, two uplinks in the previous field 2 uplink subframes of the corresponding position in the frame and the next field; or 2 uplink subframes in the previous field in the TDD frame structure configuration type 3 or 4; or, the period is lms, and the position is: All uplink subframes in type 0, 3 or 6 are configured in the TDD frame structure.

In addition, as mentioned above, the period in which the channel information is reported in the TDD mode is lms: in each frame, each uplink subframe is used to report channel information; and in Table 6, it can be seen: For the TDD frame structure configuration type 1 Selecting subframes 2, 3, 7, and 8 to report channel information. For TDD frame structure configuration type 4, selecting subframes 2 and 3 to report channel information, both of which satisfy the requirement that the period of reporting channel information is lms. Therefore, for the sake of convenience, the above two cases can be combined with the case where the reporting period shown in Table 7 is lms to form a new report letter. The channel information period is lms configuration, as shown in Table 8.

Table 8

The embodiment of the present invention further provides a system for reporting channel information in a TDD system, including: a base station, configured to send RRC signaling to a UE, instructing a UE to report channel information on a PUCCH, and a periodic subframe offset position configuration;

The RRC signaling includes: a cyclic subframe offset position parameter periodically reporting a wideband CQI or ΡΜΙ on a PUCCH, a periodic subframe offset position parameter periodically reporting a sub-band CQI or a PMI on a PUCCH, and a period of periodically reporting an RI on a PUCCH a subframe offset position parameter; the length of the three parameters is determined by a TDD frame structure configuration, and the determined manner is: determining a probability number of a periodic subframe offset position of the reported channel information according to the TDD frame structure configuration, Determining the length of the parameter according to the number of possibilities;

In the above system, when the maximum period of the upper 4 艮 channel information is 40 milliseconds, the length of the periodic subframe offset position parameter periodically reporting the wideband CQI or PMI on the PUCCH is 6 bits; the periodic reporting of the sub-band CQI or PMI on the PUCCH The length of the periodic subframe offset position parameter is 6 bits; the length of the periodic subframe offset position parameter of the periodic reporting RI on the PUCCH is 8 bits.

When the maximum period of the uplink channel information is 160 milliseconds, the length of the periodic subframe offset position parameter of the period 艮艮 wideband CQI or ΡΜΙ on the PUCCH is 8 bits; the periodic subframe offset position of the periodic report RI on the PUCCH The length of the parameter is 10 bits.

In the above system, the period and location configuration may include: a period of 2 milliseconds, and the location is: in the TDD frame structure configuration type 0, 1 or 6, 2 uplink subframes and the next subframe in the previous field 2 uplink subframes corresponding to the location; or 2 uplink subframes in the previous half frame in the TDD frame structure configuration type 3 or 4.

The period and location configuration may also include: The period is 1ms, and the location is: All uplink subframes in the TDD frame structure configuration type 0, 3 or 6.

Alternatively, the foregoing period and location configuration may include: a period of 1 millisecond, and the location is: all uplink subframes in the TDD frame structure configuration type 0, 1, 3, 4 or 6.

It can be seen that the method and the system provided by the present invention are characterized in that the system parameters of the channel information are reported to the UE when the base station sends the system parameters for reporting the channel information to the UE, so that the system parameters of the shorter length are used. The signaling overhead of the TDD system can be saved, and the switching information overhead in the TDD system is closer to the FDD system, thereby improving the compatibility of the two systems. In addition, the embodiment of the present invention also proposes a channel information location configuration with a period of 1 ms and 2 ms, so that the minimum period of reporting channel information in the TDD system can be reached. Lms, can improve the performance of TDD systems

Claims

Claim

A method for time-dividing four-channel information in a TDD system, the method comprising:

The base station sends the radio resource control RRC signaling to the user equipment UE, and indicates the period in which the UE reports the channel information on the physical uplink control channel PUCCH, and the periodic subframe offset position configuration;

The RRC signaling includes: periodically reporting a wideband channel quality information CQI on a PUCCH or a periodic subframe offset position parameter of a precoding matrix indicating PMI, a periodic subframe offset position parameter of a periodic reporting subband CQI or a PMI on a PUCCH, and The periodic sub-frame offset position parameter of the rank indication RI is periodically reported on the PUCCH; the length of the three parameters is determined by the TDD frame structure configuration, and the determined manner is: determining a periodic subframe for reporting channel information according to the TDD frame structure configuration The number of possible positions of the partial position, determining the length of the parameter according to the number of possibilities;

The UE reports the channel information on the PUCCH according to the periodic subframe offset position configuration.

The method according to claim 1, wherein when the maximum period of the reported channel information is 40 milliseconds, the length of the periodic subframe offset position parameter periodically reporting the wideband CQI or PMI on the PUCCH is 6 bits. The length of the periodic subframe offset position parameter of the cyclically reported sub-band CQI or PMI on the PUCCH is 6 bits; the length of the periodic subframe offset position parameter of the periodic reporting RI on the PUCCH is 8 bits.

The method according to claim 1, wherein when the maximum period of the reported channel information is 160 milliseconds, the length of the periodic subframe offset position parameter of the wideband CQI or PMI on the PUCCH is 8 bits; the length of the periodic subframe offset position parameter periodically reporting RI on the PUCCH is 10 bits.

The method according to claim 1, wherein the period subframe offset bit The configuration includes: The period is 1 millisecond, and the position is: All uplink subframes in the TDD frame structure configuration type 0, 1, 3, 4 or 6.

A system for uplink channel information in a TDD system, the system comprising:

The system according to claim 5, wherein when the maximum period of the reported channel information is 40 milliseconds, the length of the periodic subframe offset position parameter periodically reporting the wideband CQI or PMI on the PUCCH is 6 bits. The length of the periodic subframe offset position parameter of the cyclically reported sub-band CQI or PMI on the PUCCH is 6 bits; the length of the periodic subframe offset position parameter of the periodic reporting RI on the PUCCH is 8 bits.

The system according to claim 5, wherein when the maximum period of the reported channel information is 160 milliseconds, the length of the periodic subframe offset position parameter of the wideband CQI or PMI on the PUCCH period is 8 bits; the length of the periodic subframe offset position parameter periodically reporting RI on the PUCCH is 10 bits.

The system according to claim 5, wherein the periodic subframe offset location configuration comprises: a period of 1 millisecond, the location is: in the TDD frame structure configuration type 0, 1, 3, Or all uplink subframes in 6.