WO2010118617A1

WO2010118617A1 - Method for sending downlink midambles in a wireless communication system

Info

Publication number: WO2010118617A1
Application number: PCT/CN2009/075881
Authority: WO
Inventors: 梁婷; 朱登魁; 刘颖; 李子荣
Original assignee: 中兴通讯股份有限公司
Priority date: 2009-04-14
Filing date: 2009-12-23
Publication date: 2010-10-21
Also published as: CN101867948A; CN101867948B

Abstract

A method for transmitting downlink midambles on a wireless communication system is provided. A base station transmits midambles at one or two symbols of the 3rd or the 4th or the 7th symbol in downlink sub-frames. When the number of transmitting antennas of the base station is 2 or 4, the base station sends midambles at the 3rd or the 4th or the 7th symbol in downlink sub-frames. When the number of transmitting antennas of the base station is 8, the base station sends midambles at the 3rd and 4th symbols or the 3rd and 7th symbols or the 4th and 7th symbols in downlink sub-frames. Transmitting midambles using the method of the present invention can, when a terminal uses dedicated pilots, accurately measure the real channel situation of a downlink, and enable Precode Matrix Indication (PMI), Rank Indication (RI) and Channel Quality Information(CQI) feedback. At the same time, the method of the present invention provides both lower complexity and improved pilot tracking capability.

Description

Method for transmitting downlink intermediate pilot in wireless communication system

The present invention belongs to the field of wireless communication technologies, and in particular, to a method for transmitting a downlink intermediate pilot in a wireless communication system. Background technique

Many new technologies have emerged in the field of wireless communications, such as Orthogonal Frequency Division Multiplexing (OFDM) and Multiple-Input Multiple-Output (MIMO), which can greatly improve communication systems. The performance to meet the growing data business needs of people. In order to further improve the transmission quality, the MIMO-encoded data stream and pilot can be pre-coded and then mapped to different antennas for transmission. This also creates a dedicated pilot. In a MIMO system using a dedicated pilot mode, a channel obtained by channel estimation is an equivalent channel after precoding, and for a system that needs to feed back a real channel condition, if an equivalent channel is converted into a real channel, It will be very complicated, even impossible to achieve; in addition, for a terminal that does not have any data transmission for a period of time, it is not possible to periodically obtain a true channel situation. To do this, there is a need to have a way to measure the current true channel conditions to meet the system feedback needs.

Intermediate pilot refers to the insertion of a specific pilot sequence on a symbol in a frame for channel measurement at the receiving end. The intermediate pilot can be used to estimate the channel of all carrier locations on the entire symbol, thus facilitating the sender to reasonably adopt an efficient transmission strategy based on the current channel conditions.

In the wireless communication system, the intermediate pilot is reasonably utilized to measure the true channel condition, and the Channel Quality Information (CQI), the Precoding Matrix Indication (PMI), and the rank of the channel ( Rank Indication) are correctly fed back. , RI ), for Improving the transmission efficiency of the system plays an important role.

Therefore, how to choose the appropriate timing to send the intermediate pilot and the format of the intermediate pilot to achieve better channel measurement is a problem that the technician must consider. Summary of the invention

The technical problem to be solved by the present invention is to provide a method for transmitting a downlink intermediate pilot in a wireless communication system, so that the terminal achieves a better channel measurement effect.

In order to solve the above technical problem, the present invention provides a method for transmitting a downlink intermediate pilot in a wireless communication system, including:

The base station transmits the intermediate pilot on one or both of the third or fourth or seventh symbols in the downlink subframe.

Preferably, when the number of transmitting antennas of the base station is 2 or 4, the base station transmits the intermediate pilot on the third or fourth or seventh symbol in the downlink subframe.

Preferably, when the number of transmitting antennas of the base station is 8, the base station transmits pilots on the third and fourth symbols or the third and seventh symbols or the fourth and seventh symbols in the downlink subframe.

In order to solve the above technical problem, the present invention further provides a method for transmitting a downlink intermediate pilot in a wireless communication system, including:

The base station sends an intermediate pilot in one or more subframes except the first subframe in the downlink frame; or the base station transmits the intermediate pilot in one downlink subframe of the downlink superframe in one or more subframes except the first subframe. .

Preferably, the base station transmits the intermediate pilot in the last downlink subframe of the downlink frame, or the base station transmits the intermediate pilot in the last subframe of a downlink frame of the downlink superframe.

Preferably, when the terminal accesses, the base station notifies the terminal of the downlink subframe position of the intermediate pilot by using the access control related message.

In order to solve the above technical problem, the present invention also provides a method for transmitting a downlink intermediate pilot in a wireless communication system, including: a base station by broadcasting a control channel and/or a unicast control channel Sending a message notifying the user terminal of the position of the intermediate pilot in the downlink frame <

Preferably, the message includes at least one of the following:

1) Whether the current frame sends measurement pilot information

2) Sub-frame index of the intermediate pilot in the frame

3) Intermediate pilot in the sub-frame symbol index

4) the boosting power corresponding to the intermediate pilot;

Preferably, the base station sends a message through the broadcast control channel and/or the unicast control channel to notify the terminal whether the current superframe and/or the frame sends the intermediate pilot. If the base station transmits, the base station sends the intermediate pilot in one of two ways:

2) transmitting an intermediate pilot on one or more symbols of the downlink frame and/or the subframe, and transmitting a message through the broadcast control channel and/or the unicast control channel to inform the terminal of the subframe and the symbol position where the intermediate pilot is located. The continuous S frame of the frame in which the current message is located is offset from the AS frame, and the intermediate pilot is transmitted in a periodic T frame, and the frame corresponding to the intermediate pilot is transmitted through the broadcast control channel and/or the unicast control channel to notify the terminal. The index of the subframe to which the pilot symbol belongs, where AS, S, and T are natural numbers.

By using the method of the present invention to transmit the intermediate pilot, it is possible to accurately measure the true channel condition of the downlink when the terminal uses the dedicated pilot, and complete the feedback of the PMI, RI and CQI. At the same time, the method of the present invention has both low complexity and good pilot tracking capability. DRAWINGS

1 is a data and pilot distribution in a basic resource block of a downlink subframe in the 802.16m standard. FIG. 2 is a flowchart of a method for transmitting an intermediate pilot according to the present invention.

Figure 3 (a) is a schematic diagram of an intermediate pilot insertion pattern of a basic resource block of Example 1. Figure 3 (b) is a schematic diagram of the intermediate pilot insertion pattern of the example 2 - basic resource block.

Figure 4 (a) is a schematic diagram of an intermediate pilot insertion mode of a basic resource block corresponding to Example 3.

Figure 4 (b) is a schematic diagram of an intermediate pilot insertion mode of a basic resource block corresponding to Example 4.

Figure 5 (a) - Figure 5 (c) is a basic pilot block intermediate pilot insertion pattern corresponding to Example 5.

Figure 6 (a) is a basic pilot block intermediate pilot insertion pattern corresponding to Example 6.

Figure 6 (b) is a schematic diagram of an intermediate pilot insertion mode of a basic resource block corresponding to Example 7.

Figure 7 (a) - Figure 7 (c) is a basic resource block intermediate pilot insertion pattern corresponding to Example 8.

Figure 8 (a) - Figure 8 (b) is a basic pilot block intermediate pilot insertion pattern corresponding to Example 9.

Figure 9 (a) - Figure 9 (b) is a basic resource block intermediate pilot insertion pattern corresponding to Example 10.

Figure 10 (a) - Figure 10 (b) is a basic resource block intermediate pilot insertion pattern corresponding to Example 11.

Figure 11 (a) - Figure 11 (b) is a basic resource block intermediate pilot insertion pattern corresponding to Example 12. detailed description

The main idea of the present invention is to select the downlink frame and the downlink subframe to which the intermediate pilot is to be transmitted, and after selecting all the data demodulation pilots on each symbol in the downlink subframe, the number of remaining carriers is the largest. One symbol (the number of transmitting antennas of the base station is 2 or 4 at this time) or two consecutive (the number of transmitting antennas of the base station is 8) transmits the intermediate pilot.

The technical solution of the present invention will be described in detail below with reference to the accompanying drawings and preferred embodiments.

Referring to FIG. 1 , it is a schematic diagram of data and pilot distribution in a basic resource block (Resource Unit, RU unit) of a downlink subframe in the 802.16m standard. According to the 802.16m standard, a basic resource block is structured to include 5 or 6 or 7 OFDM symbols in the time direction and 18 subcarriers in the frequency direction. 1 shows a basic resource block structure including 6 OFDM symbols in a time direction, in which grid line blocks represent data demodulation pilots, white squares represent data areas, and diagonal line blocks represent free areas. In the drawings of the invention, the meaning of the same blocks is the same. It can be seen from the structure of the basic resource block shown in FIG. 1 that the third and fourth symbols in the basic resource block are symbols with the least number of subcarriers occupied by the data demodulation pilot (ie, black squares), and the present invention considers The intermediate pilot is transmitted on these symbols.

Referring to FIG. 2, it is a flowchart of an intermediate pilot transmission method according to the present invention. The method includes the following steps:

Step 201: Determine a downlink frame and a downlink subframe that send the intermediate pilot.

Step 202: Select, in the downlink subframe, one symbol or two consecutive symbols with the largest number of remaining carriers after removing all data demodulation pilots on each symbol.

Step 203: Determine that the one or two consecutive symbols transmit a carrier position of the intermediate pilot in a frequency direction.

Step 204: Insert an intermediate pilot at the carrier position.

For the 802.16m standard, when the structure of a basic resource block includes 5 and 6 OFDM symbols in the time direction, the symbols with the least number of subcarriers occupied by the data demodulation pilot are the 3rd and 4th symbols. When a basic resource block is structured to include 7 OFDM symbols in the time direction, the symbols with the least number of subcarriers occupied by the data demodulation pilot are the 3rd, 4th, and 7th symbols.

The determining, by the step 201, the downlink frame that sends the intermediate pilot, includes:

The base station indicates, by using a broadcast message, the downlink subframe position of the intermediate pilot that is sent by the terminal; or the downlink subframe position of the intermediate pilot of the base station. The predetermined downlink subframe may be any subframe other than the first subframe in the downlink frame.

Specifically, the present invention provides an intermediate pilot configuration method for channel measurement in the downlink of an 802.16m wireless communication system, and the main contents include:

In the downlink frame of the 802.16m wireless communication system, the base station selects the jth of the i-th downlink frame (j, specifically, the base station transmits the intermediate pilot in one or more subframes except the first subframe in the downlink frame; or The base station transmits an intermediate pilot in one or more subframes except the first subframe in one downlink frame of the downlink superframe. The base station transmits the intermediate pilot in the last subframe of one downlink frame of the downlink superframe.

When the terminal accesses, the base station notifies the terminal by transmitting the downlink subframe position of the intermediate pilot by using the access control related message. In each downlink frame, the base station sends a message through the broadcast control channel and/or the unicast control channel to inform the terminal whether the current frame transmits the intermediate pilot. If the base station transmits, the base station transmits the intermediate pilot in one of two ways:

2) transmitting an intermediate pilot on one or more symbols of the downlink frame and/or the subframe, and transmitting a message through the broadcast control channel and/or the unicast control channel to inform the terminal of the subframe and symbol position where the intermediate pilot is located.

The sending the message includes one of the following:

1) Whether the current frame sends measurement pilot information

2) a sub-frame index of the intermediate pilot in the frame;

3) the intermediate pilot is indexed in the subframe; The consecutive S frames that are offset from the AS frame in the frame where the current message is located are sent with the intermediate pilot in a periodic T frame, and the message is sent to the terminal through the broadcast control channel and/or the single wave control channel in the frame corresponding to the intermediate pilot. The index of the subframe to which the intermediate pilot symbol belongs. Among them, AS, S, T are natural numbers.

The message sent by the unicast control channel is a non-user specific message of the downlink frame.

The criterion used by the base station to place the time-domain symbol index of the intermediate pilot in the selected subframe is: after removing all data demodulation pilots on each symbol (shown in FIG. 1), the one with the largest number of remaining carriers The symbol (in this case, the number of transmitting antennas of the base station is 2 or 4) or two consecutive (the number of transmitting antennas of the base station is 8) is used to transmit the intermediate pilot. That is, when the number of transmitting antennas of the base station is two or four, the base station selects the third or fourth or seventh symbol to transmit the intermediate pilot in the determined downlink subframe; when the number of transmitting antennas of the base station is eight The base station selects the third and fourth symbols in the determined downlink subframe to send the intermediate pilot.

Wherein, when the number of transmitting antennas of the base station is greater than 4 and less than or equal to 8, one of the two symbols used for transmitting the intermediate pilot transmits four different antennas corresponding to the intermediate pilot.

The criterion used by the base station to determine the frequency domain carrier position index (sequence number) of the intermediate pilot in the subframe is:

When the number of transmitting antennas is 2 or 4, the corresponding intermediate pilot carrier relative position index set Midamble_carrier_Set_PR U of the w + 1 antenna (0≤w≤3) in the basic resource block is:

Midamble _ Carrier _ Set _ PRU = 3 + n + k^As

Where = 0,1, 2,··· _ 1 , is the index of the intermediate pilot on the basic resource block; represents the number of intermediate pilots inserted by each antenna in one resource block; for each antenna in each basic The number of carrier spacing between two adjacent pilots within a resource block.

When the intermediate pilot is inserted over the full bandwidth, the occupied physical carrier position index Midamble_Carrier_Set is: Midamble Carrier Set - -l)/2 + 18 ^: + 3 + w + mod ₂

m , ) * Where, the DC subcarrier (zero carrier) is included in the sorting, but it is removed in advance when transmitting. The following embodiments are the same as this, and will not be described again.

When the intermediate pilot is inserted on a part of the resource block on the full bandwidth, occupying the physical carrier position index Midamble _ Carrier_Set is:

Midamble _ Carrier _ Set = S _k + + 2 + mod ( ^ ₂ , m ) ^ ΔΛ ¹ where = 0,1,2,·· ₂ _1 is the index of the intermediate pilot over the full bandwidth; The number of intermediate pilots inserted in the system bandwidth; the number of carrier spacing between two adjacent pilots within the basic resource block for each antenna; m is the number of each antenna within each basic resource block

The number of pilots; indicates the largest integer less than or equal to, mod^ ₂ , ) indicates the remainder divided by mmm; N _used indicates the number of remaining subcarriers after the system removes the guard interval subcarriers, ^{0,1,2,· ··Μ} is a basic resource block logical index set for inserting an intermediate pilot, and represents a physical location index corresponding to the first subcarrier of the first resource block inserted into the intermediate pilot.

The logical index means that the physical indexes of all the M+1 basic resource blocks inserted into the intermediate pilot are arranged from 0 to 按照 in order of decreasing from small to large, and the sequence number corresponding to the basic resource block is a logical index.

When the number of transmitting antennas of the base station is eight, the corresponding intermediate pilot carrier relative position index set Midamble_carrier_Set_PRU of the w + 1 antenna (0 ≤ w ≤ 7) within each basic resource block is:

Midamble Carrier Set PRU =3 + + LAs or:

Midamble _ Carrier _ Set _ PRU = 3 + mod (n, ) + k^ where the intermediate pilot of 4 antennas corresponds to the subcarrier of one symbol of the two symbols The intermediate pilots of the other four antennas are on the subcarriers corresponding to the other symbol of the two symbols.

And, when the intermediate pilot is inserted over the full bandwidth, occupying the physical carrier position index Midamble _ Carrier _ Set is:

Midamble― Carrier _Set =-( N - 1 ) / 2 + 18 * + 3 + + mod k ₂ ,m)* As m

Or for:

Midamble― Carrier _Set =-( N _used - 1 ) / 2 + 18 * + 3 + mod(n,4) + mod(^ ₂ ,m) m and, when the intermediate pilot is inserted on some resource blocks over the full bandwidth , occupying the physical carrier position of the cable I Midamble _ Carrier _ Set is:

Midamble _ Carrier _ Set = S _k + n + 2 + mod ( ^ ₂ , m ) * ΔΛ" where = 0, 1, 2, ... - 1, is the index of the intermediate pilot on the basic resource block; The number of intermediate pilots inserted by the antenna in a resource block; =0,1,2,... - 1, the index of the intermediate pilot for each antenna over the full bandwidth; indicating the middle of each antenna inserted in the system bandwidth Number of pilots; the number of intermediate pilots within each basic resource block for each antenna; the number of carrier spacing between two pilots adjacent to each antenna; indicates the minimum number less than or equal to; N ^ indicates system removal The number of all subcarriers remaining after guarding the subcarriers on both sides; ie {0,1,2,···Μ} is the basic resource block logical index set inserted into the intermediate pilot, and S,. indicates the first resource inserted into the intermediate pilot. The physical location index corresponding to the first subcarrier of the block.

The logical index refers to that the physical indexes of all the M+1 basic resource blocks inserted into the intermediate pilot are arranged in the order of 0 to M, and the sequence number corresponding to the basic resource block is a logical index.

Further optimized, in order to avoid mutual interference of pilots in adjacent cells, neighboring cells are selected The intermediate pilots are transmitted on the same subframe of different frames, or the intermediate pilots are transmitted on different subframes of the same frame, or the intermediate pilots are transmitted on different symbols of the same subframe.

Further optimized, when neighboring cells transmit intermediate pilots on the same symbol of the same subframe, the neighboring cells use different code sequences as pilot signals, thereby avoiding interference between cells.

Further, when the neighboring cells send the intermediate pilots on the same symbol of the same subframe, if the base station transmits two antennas, the neighboring cells insert the intermediate pilots by means of frequency division multiplexing.

The frequency division multiplexing refers to that the neighboring cell selects a different carrier set in the same symbol frequency domain in the basic resource block to transmit the intermediate pilot, and the pilot carrier used in each basic resource block of the adjacent three cells The aggregate and full bandwidth intermediate pilot carrier physical location index set is:

For cell 1:

Carrier Set _PRU =3 + n + k,As k

Midamble _ Carrier _Set =-( N _used - 1 ) / 2 + 18 : + 3 + n + mod(^ ₂ ,m) *Ay m

Carrier set used by cell 2:

Midamble _ Carrier _Set _PRU = 3 + n + k, As + A

L

•_Carrier_Set =-(N _used -l)/2 + 18 + 3 + n + mod(k ₂ ,m)*As + m

Carrier set used by cell 3:

Midamble _ Carrier _Set_PRU = 3 + n + k, As + 2Δ k

Midamble _ Carrier _Set =-( N _used -l)/2 + 18 ^: + 3 + n + mod(k ₂ ,m)*As + 2Δ m

Where is the number of carrier spacings in the frequency domain of the intermediate pilots within each basic resource block of the neighboring cell.

The terminal includes a relay station, a mobile phone, a notebook, and everything else that can implement channel measurement based on the intermediate pilot. To make the technical solution of the present invention easier to understand, the following technical examples are applied to the present invention. The program is explained. Of course, there are a plurality of specific application examples and are not limited thereto, but in view of limited space, only examples are exemplified herein.

Example 1:

This example is used to illustrate the location of the intermediate pilot in the basic resource block when the base station configures two transmit antennas: The position of the intermediate pilot in the subframe is the fourth symbol of the subframe. 3(a) shows only the carrier position where the intermediate pilot occupies the 4th symbol when the basic resource block structure is 18x6, and the carrier position of the 4th symbol when the basic resource block is 18x7. The location described below is the same. The carrier position occupied by the intermediate pilot is specifically described below.

Figure 3 (a) shows a schematic diagram of the transmission position of the intermediate pilot of the 18 x 6 basic resource block, wherein the intermediate pilot is inserted on the fourth symbol, where P1 is the intermediate pilot of antenna 1, and P2 is the antenna. 2 intermediate pilots.

Example 2:

This example is used to illustrate the position of the intermediate pilot in the basic resource block when the base station configures two transmit antennas: The position of the intermediate pilot in the subframe is the third symbol of the subframe. Figure 3 (b) shows the carrier position where the intermediate pilot occupies the third symbol when the basic resource block structure is 18 x 6, and the intermediate pilot occupies the first when the basic resource block structure is 18 x 7 or 18 x 5 The carrier positions of the three symbols are the same as those described below. The carrier position occupied by the intermediate pilot is specifically described below.

The carrier position occupied by the intermediate pilot is specifically described below with a subframe structure of 18 x 6.

3(b) is a schematic diagram of a transmission position of an intermediate pilot of an 18×6 basic resource block, where an intermediate pilot is inserted on a third symbol, where P1 is the intermediate pilot of antenna 1, and P2 is antenna 2 Intermediate pilot.

Example 3

This example is used to illustrate the location of the intermediate pilot in the basic resource block when the base station configures 4 transmit antennas: The position of the intermediate pilot in the subframe is the fourth symbol of the subframe. Figure 4 (a) shows only the carrier position where the intermediate pilot occupies the 4th symbol when the basic resource block structure is 18 x 6 When the basic resource block structure is 18x7, the carrier position of the fourth pilot occupying the fourth symbol is the same as the position described below. The carrier position occupied by the intermediate pilot is specifically described below.

4(a) is a schematic diagram of a transmission position of an intermediate pilot block of an 18×6 basic resource block, where an intermediate pilot is inserted on a fourth symbol, where P1 is the intermediate pilot of antenna 1, and P2 is the intermediate pilot of antenna 2. P3 is the intermediate pilot of antenna 3, and P4 is the intermediate pilot of antenna 4.

Example 4

This example is used to illustrate the location of the intermediate pilot in the basic resource block when the base station configures four transmit antennas: The position of the intermediate pilot in the subframe is the third symbol of the subframe. 4 shows that when the basic resource block structure is 18x6, the intermediate pilot occupies the carrier position of the third symbol, and when the basic resource block structure is 18x5 or 18x7, the intermediate pilot occupies the carrier position of the third symbol and is described below. The same location. The carrier position occupied by the intermediate pilot is specifically described below.

4(b) is a schematic diagram showing the transmission position of the intermediate pilot of the basic resource block structure of the four antennas, wherein the intermediate pilot is also inserted on the third symbol, where P1 is the intermediate pilot of the antenna 1, and P2 is the antenna 2. The intermediate pilot, P3 is the intermediate pilot of antenna 3, and P4 is the intermediate pilot of antenna 4.

Example 5

This example is used to illustrate that when a base station configures two transmit antennas, neighboring base stations adopt frequency division multiplexing to avoid interference between adjacent cells.

Referring to Fig. 5 (a) - Fig. 5 (c), the intermediate pilot corresponding to the example 5 is inserted into the pattern diagram. In this example, a basic resource block is structured to include 6 OFDM symbols in the time direction. According to the method of transmitting intermediate pilots of the present invention, the intermediate pilot is transmitted on the third or fourth symbol of the downlink. (Only the case where the fourth symbol is transmitted is shown in the figure).

In this example, where the basic resource block structure is 18x5 (frequency X time domain), the intermediate pilot is placed on the third symbol, when the basic resource block structure is 18 X 6 or 18 X 7 (frequency X time domain) When the intermediate pilot is placed on the third or fourth symbol, the following description of Figure 18 shows 18x6 The basic resource block corresponds to the carrier position occupied by the intermediate pilot when placed at the 4th symbol. When the intermediate pilot is placed on the third symbol, the intermediate pilot occupies the same carrier position as the present example.

Figure 5 (a) shows the insertion method of the intermediate pilot of the subframe structure of the two antennas of the base station 1, the intermediate pilot is inserted on the fourth symbol, and the interval of the adjacent pilots of each antenna is 8 subcarriers. Medium P1 is the intermediate pilot of antenna 1, and P2 is the intermediate pilot of antenna 2. 5(b) and 5(c) are schematic diagrams showing the transmission positions of the intermediate pilots of the adjacent base station 2 and the base station 3, respectively, wherein the transmission position of the intermediate pilot is similar to that of FIG. 5(a), and the base station 2 and the base station 3 The same intermediate pilot and base station 1 are separated by 2 and 4 subcarriers, respectively. Thus, three neighboring cells insert pilots at different subcarrier positions of the same symbol, and the intermediate pilot interval of the neighboring base stations is 2, which is orthogonal in frequency, so that the condition of the channel can be measured with less overhead.

Example 6

This example is used to illustrate the case where the intermediate pilot is placed on the seventh symbol when the base station is configured with two transmit antennas and the subframe has seven time domain symbols.

Referring to FIG. 6(a), a pattern map is inserted in the basic resource block for the intermediate pilot corresponding to Example 6. Figure 6 (a) is taken as an example to illustrate the case of two antennas, and Figure 6 (a) is a schematic diagram of the insertion mode of the intermediate pilot of each basic resource block in the subframe structure of two antennas, wherein the intermediate pilot Inserted on the seventh symbol, and the adjacent intermediate pilot interval of each antenna is 2 subcarriers, where P1 is the intermediate pilot of antenna 1, and P2 is the intermediate pilot of antenna 2.

Example 7

This example is used to illustrate the case where the intermediate pilot is placed on the seventh symbol when the base station is configured with four transmit antennas and the subframe has seven time domain symbols.

Referring to 6 (b), the mode map of the intermediate pilot corresponding to the example 7 is inserted.

Figure 6 (b) is used as an example to illustrate the situation of four antennas, and Figure 6 (b) is a schematic diagram of the insertion of intermediate pilots of the basic resource blocks of four antennas, where adjacent intermediate pilots of each antenna The interval is 4 subcarriers, where P1 is the intermediate pilot of antenna 1, and P2 is the intermediate guide of antenna 2. Frequency, P3 is the intermediate pilot of antenna 3, and P4 is the intermediate pilot of antenna 4.

Example 8

This example is used to illustrate the case where the base station has 2 antennas and the intermediate pilot is placed on the 7th symbol of the subframe with 7 time domain symbols, and the neighboring base stations avoid mutual intermediate conduction by means of frequency division. Frequency interference.

Referring to Fig. 7 (a) - Fig. 7 (c), the intermediate pilot corresponding to the example 8 is inserted into the pattern diagram. In this example, the structure of one basic resource block is 7 OFDM symbols in the time direction, and the method for transmitting intermediate pilots according to the present invention is shown in the figure, in which the intermediate pilot is transmitted in the seventh symbol, And, the intermediate pilots of the neighboring cells are at different positions in the same symbol.

7( a ) is a schematic diagram of a transmission position of an intermediate pilot of a subframe structure of two antennas of a base station 1 , wherein an intermediate pilot is inserted on a seventh symbol, and an interval of adjacent pilots of each antenna is 8 sub-intervals. Carrier, P1 is the intermediate pilot of antenna 1, and P2 is the intermediate pilot of antenna 2. 7(b) and 7(c) are schematic diagrams showing the transmission positions of the intermediate pilots of the neighboring base station 2 and the base station 3, respectively, and the transmission position of the intermediate pilot is similar to that of FIG. 7(a), and the base station 2 and the base station 3 are the same. The interval between the intermediate pilot and the base station 1 is 2 and 4 subcarriers, respectively. Such three neighboring cells insert pilots at different subcarrier positions of the same symbol and are orthogonal in frequency, so that the condition of the channel can be measured with less overhead while avoiding interference between adjacent cells.

Example 9

This example is used to illustrate the case where the base station has 8 transmit antennas and the intermediate pilots are placed on the 3rd and 4th symbols of the subframe.

8( a ) is a schematic diagram of a transmission position of an intermediate pilot in a basic resource block having 6 symbol downlink subframes when the base station uses 8 antennas, where, for a basic resource block having 7 symbol downlink subframes, The carrier position of the intermediate pilot occupying the 3rd and 4th symbols is the same as the position described below.

Where P1 is the intermediate pilot of antenna 1, P2 is the intermediate pilot of antenna 2, and P3 is antenna 3. The intermediate pilot, P4 is the intermediate pilot of the antenna 4, P5 is the intermediate pilot of the antenna 5, P6 is the intermediate pilot of the antenna 6, P7 is the intermediate pilot of the antenna 7, and P8 is the intermediate pilot of the antenna 8, Each antenna has 3 pilots in each basic resource block, and each antenna has a pilot interval of 4 carriers. Figure 8 (b) is another mapping between antenna pilots and symbols and carriers. the way.

Example 10

This example is for explaining the case where the base station has 8 transmit antennas and the intermediate pilot is placed on the 3rd and 4th symbols of the subframe having 6 time domain symbols.

9( a ) is an insertion method of intermediate pilots at different densities within a basic resource block having 6 symbol downlink subframes when the base station uses 8 antennas, and is used for a basic resource block having 7 symbol downlink subframes The carrier position of the intermediate pilot occupying the 3rd and 4th symbols is the same as the position described below.

Where P1 is the intermediate pilot of antenna 1, P2 is the intermediate pilot of antenna 2, P3 is the intermediate pilot of antenna 3, P4 is the intermediate pilot of antenna 4, P5 is the intermediate pilot of antenna 5, and P6 is the antenna 6 of antenna 5. Intermediate pilot, P7 is the intermediate pilot of antenna 7, and P8 is the intermediate pilot of antenna 8. For less overhead, each antenna has 2 pilots inside each basic resource block, and each antenna is adjacent. The pilot interval is 8 carriers; Figure 9 (b) is another way of mapping between antenna pilots and symbols and carriers.

8 is different from FIG. 9 in that each antenna in FIG. 8 has 3 pilots in each basic resource block, and each antenna adjacent pilot interval is 4 carriers; and each of FIG. The antenna has two pilots in each basic resource block, and each pilot has an adjacent pilot interval of 8 carriers. It can be seen that the intermediate pilot is transmitted by using the transmission position shown in FIG. 9, as shown in FIG. The location sends intermediate pilots, which saves system resources.

Example 11

This example is used to illustrate a case where a base station has 8 transmit antennas and an intermediate pilot is placed on the 3rd and 7th symbols of a subframe having 7 time domain symbols. 10( a ) is a schematic diagram of a transmission position of an intermediate pilot in a basic resource block having 7 symbol downlink subframes when the base station uses 8 antennas, where P1 is the intermediate pilot of antenna 1 and P2 is antenna 2 Intermediate pilot, P3 is the intermediate pilot of antenna 3, P4 is the intermediate pilot of antenna 4, P5 is the intermediate pilot of antenna 5, P6 is the intermediate pilot of antenna 6, P7 is the intermediate pilot of antenna 7, P8 For the intermediate pilot of the antenna 8, each antenna has 3 pilots within each basic resource block, and each antenna has an adjacent pilot interval of 4 carriers; FIG. 10(b) is another antenna pilot. The way of mapping between symbols and carriers.

Example 12

This example is for explaining the case where the base station has 8 transmit antennas and the intermediate pilot is placed on the 4th and 7th symbols of the subframe having 7 time domain symbols.

11( a ) is a schematic diagram of a transmission position of an intermediate pilot in a basic resource block having 7 symbol downlink subframes when the base station uses 8 antennas, where P1 is the intermediate pilot of antenna 1 and P2 is antenna 2 Intermediate pilot, P3 is the intermediate pilot of antenna 3, P4 is the intermediate pilot of antenna 4, P5 is the intermediate pilot of antenna 5, P6 is the intermediate pilot of antenna 6, P7 is the intermediate pilot of antenna 7, P8 For the intermediate pilot of the antenna 8, each antenna has 3 pilots within each basic resource block, and each antenna has a pilot interval of 4 carriers; Figure 11 (b) is another antenna pilot. The way of mapping between symbols and carriers.

Example 13

This embodiment illustrates that a neighboring cell transmits intermediate pilots at the same position of different downlink subframes to avoid mutual interference of adjacent pilots of adjacent cells.

In this example, the base station negotiates and determines when all users access: The base station sends the downlink intermediate pilot every T frame, wherein the configuration between the adjacent three base stations is as follows:

The base station 1 places an intermediate pilot on the jth (j is less than or equal to the number of subframes included in the downlink frame) of the downlink frame whose index is i+Z x T (Z is an integer greater than 0), and the base station 2 is indexed as i. The intermediate pilot is placed on the jth subframe of the downlink frame of +ZX T+1, and the base station 3 is downlinked at i+ZX T+2. An intermediate pilot is placed on the j subframes of the frame.

Example 14

This example shows that each base station determines the subframe index of the intermediate pilot according to the status of the downlink user. When the number of transmitting antennas of the base station is 2, 4, and 8, respectively, the default pilot insertion mode is adopted in the corresponding subframe. An intermediate pilot is inserted inside each basic resource block, and then the user is notified by an intermediate pilot related broadcast information, for example, the broadcast message in the downlink frame carries two indication fields:

Midamble_Enable , Midamble—Position—Index, _ When Midamble_Enable = 0, it means that the frame does not send the intermediate pilot, and the user no longer detects the position information of the intermediate pilot;

When Midamble_Enable = 1, this frame has an intermediate pilot transmission. In this case, Midamble_Position_Index can be used to indicate the index number of the subframe in which the intermediate pilot is transmitted in the frame. After detecting the message, the user can detect the intermediate pilot at the corresponding location.

Example 15

This example shows that each base station informs the user whether the intermediate pilot is transmitted by the broadcast control information or the unicast control message associated with the intermediate pilot in the downlink frame. If the intermediate pilot is transmitted, it is transmitted on the last subframe. For example, a broadcast message in a downstream frame carries an indication field:

Midamble_Enable, if Midamble_Enable = 0, no transmission, if Midamble_Enable = 1, then send the intermediate pilot on the last downlink subframe. When the number of transmitting antennas of the base station is 2, 4, and 8, respectively, the default pilot insertion mode of FIG. 3 (a), FIG. 3 (b), and FIG. 7 (a) are used in each basic resource of the subframe. The intermediate pilot is inserted inside the block.

Example 16

This example illustrates that a base station transmits an intermediate pilot on a predetermined downlink subframe, where a predetermined downlink subframe is a subframe other than the first subframe. For example, it is predetermined that the index of the downlink subframe in the downlink frame in the downlink frame is the second subframe. In each frame, the base station carries an indication field in the message transmitted by the broadcast control channel or the unicast control channel of the downlink frame: Midamble_Enable, if Midamble_Enable = 0, it is not sent, if Midamble_Enable = 1 , then The intermediate pilot is transmitted on two downlink subframes. When the number of transmitting antennas of the base station is 2, 4, or 8, the intermediate pilot is inserted into the basic resource block of the corresponding subframe by using the default intermediate pilot insertion method.

Example 17

This example illustrates that the base station notifies the user of the location of the intermediate pilot by using a broadcast control message or a unicast control downlink: The base station determines whether the current frame transmits the intermediate pilot by transmitting a broadcast control message or a unicast control message: and the base station transmits in the ith frame. A broadcast control message or a unicast control message informs the user that it will transmit the downlink intermediate pilot from the i+2th frame to the i+102 frame and the T=4 frame period, and the base station transmits the broadcast in the corresponding frame. The message informs the user that the intermediate pilot is in the subframe index to which the current frame belongs. When the number of transmit antennas of the base station is 2, 4, or 8, the default pilot insertion mode is used to insert the intermediate guide in the basic resource block of the corresponding subframe. Frequency, such that the terminal detects the corresponding intermediate pilot in the corresponding subframe.

The predetermined downlink subframe in the example 18 is the case of other subframes except the first subframe. For example, the intermediate pilot is pre-defined to be transmitted in the second subframe of the first downlink frame in the superframe. In each superframe, the base station carries an indication field in the message sent by the broadcast control channel of the downlink superframe or the unicast control channel: Midamble_Enable, if Midamble_Enable = 0, it is not sent, if Midamble_Enable = 1 , then The intermediate pilot is transmitted on the second subframe of the first downlink frame of the superframe. When the number of transmitting antennas of the base station is 2, 4, or 8, the intermediate pilot is inserted into the basic resource block of the corresponding subframe by using the default intermediate pilot insertion method.

It should be noted that the above description is only a preferred embodiment of the present invention, and is not intended to further limit the technical solution of the present invention, and the scope of protection of the present invention is not limited thereto, and any person familiar with the technology is disclosed in the present invention. Variations or substitutions that are conceivable within the scope of the invention are intended to be encompassed within the scope of the invention. Therefore, the scope of protection of the present invention should be in the claims The scope of protection shall prevail.

Claims

Claim

A method for transmitting a downlink intermediate pilot in a wireless communication system, comprising:

The method according to claim 1, wherein when the number of transmitting antennas of the base station is 2 or 4, the base station sends the middle on the third or fourth or seventh symbol in the downlink subframe. Pilot.

The method according to claim 1, wherein when the number of transmitting antennas of the base station is 8, the third and fourth symbols of the base station in the downlink subframe, or the third and seventh The pilot is transmitted on the symbol, or on the fourth and seventh symbols.

The method according to claim 1, wherein the method further comprises: the base station transmitting an intermediate pilot on a frequency domain subcarrier of one or two symbols of the downlink subframe.

The method according to claim 4, wherein the base station sends an intermediate pilot on a frequency domain subcarrier of one or two symbols of a downlink subframe;

When the number of transmitting antennas is 2 or 4, the "+1 antennas correspond to the intermediate pilot carrier relative position index set in the basic resource block. Midamble_Carrier-Set_PRU^'.

Midamble _ Carrier _ Set _ PRU = 3 + n + k^As;

Where = 0,1, 2, · · ₁ _ 1 is the index of the intermediate pilot on the basic resource block; indicates the number of intermediate pilots inserted by each antenna in one resource block; for each antenna in each basic The number of carrier spacing between two adjacent pilots within a resource block; 0 ≤ "≤ 3.

The method according to claim 5, wherein the base station sends the intermediate pilot on the frequency domain subcarrier of one or two symbols of the downlink subframe, and further includes:

When the intermediate pilot is inserted over the full bandwidth, it occupies the physical carrier position index Midamble _ Carrier _ Set is

Midamble— Carrier— Set =-(N _used -l)/2 + 18 ^: + 3 + + mod( ₂ , )*Ay; m

Midamble— Carrier— Set = S _k + + 2 + mod ( ^ ₂ , m ) ^ ΔΛ ¹ ; where = 0,1,2,·· ₂ _1 is the index of the intermediate pilot over the full bandwidth; The number of intermediate pilots inserted by the antenna over the system bandwidth; the number of carrier spacing between two adjacent pilots within the basic resource block for each antenna; m is the intermediate pilot of each antenna within each basic resource block Quantity; represents the largest integer less than or equal to ^, mod^ ₂ , ) represents the remainder of the division by mmm; N „^ represents the number of remaining subcarriers after the system removes the guard interval subcarriers, S,. indicates the first insertion of the intermediate pilot The physical location index corresponding to the first subcarrier of the resource block, {0, 1, 2, is the basic resource block index set that needs to be inserted into the intermediate pilot.

The method according to claim 4, wherein the base station sends the intermediate pilot on the frequency domain subcarriers of the two symbols of the downlink subframe, including:

When the number of transmitting antennas of the base station is eight, the corresponding intermediate pilot carrier relative position index set of the w + 1 antennas within each basic resource block is Midamble _ Carrier_Set_PRU^

Midamble Carrier Set PRU =3 +

Or for:

Midamble _ Carrier _ Set _ PRU = 3 + mod (n, ) + k^ ;

The intermediate pilot of the four antennas is on the subcarrier corresponding to one symbol of the two symbols, and the intermediate pilot of the other four antennas is on the subcarrier corresponding to the other symbol of the two symbols; <η<Ί.

The method according to claim 7, wherein the base station sends the intermediate pilot on the frequency domain subcarriers of the two symbols of the downlink subframe, and further includes:

When the intermediate pilot is inserted over the full bandwidth, it occupies the physical carrier position index

Midamble _ Carrier _ Set is:

Midamble _ Carrier _Set =-( N - 1 ) / 2 + 18 ^: + 3 + + mod k ₂ ,m)* As

Or for:

k,

Midamble _ Carrier _Set =-( N _med -l)/2 + 18 ^: + 3 + mod(n,4) + mod(^ ₂ ,m) m and, when the intermediate pilot is inserted on some resource blocks over the full bandwidth , occupying the physical carrier position of the cable I Midamble _ Carrier _ Set is:

Midamble Carrier Set =S, + n + 2 + mod k ₂ ,m)*As; where = 0,1,2,... - 1 is the index of the intermediate pilot on the basic resource block; The number of intermediate pilots inserted in the resource block; =0,1,2,... - 1, the index of the intermediate pilot for each antenna over the full bandwidth; indicates the number of intermediate pilots inserted by each antenna over the system bandwidth ; the number of intermediate pilots within each basic resource block for each antenna; the number of carrier spacing between two pilots adjacent to each antenna; represents the minimum less than or equal to

2; N „^ indicates the number of all subcarriers remaining after the system removes the guard interval subcarriers; S, indicates the physical location index corresponding to the first subcarrier of the first resource block inserted into the intermediate pilot, {0, 1 , 2, is a basic resource block index set that needs to insert an intermediate pilot;

The intermediate pilot of the four antennas is on the subcarrier corresponding to one symbol of the two symbols, and the intermediate pilot of the other four antennas is on the subcarrier corresponding to the other symbol of the two symbols.

The method according to claim 1, wherein the method further comprises: selecting, by a neighboring cell, the same subframe of different frames, or different subframes of the same frame, or sending on different symbols of the same subframe Intermediate pilot

Or, the neighboring cells send intermediate pilots on the same symbol of the same subframe, and use different code sequences as pilot signals;

Alternatively, the neighboring cells send intermediate pilots on the same symbol of the same subframe. When the base station transmits two antennas, the neighboring cells transmit the intermediate pilots by frequency division multiplexing.

The method according to claim 9, wherein the frequency division multiplexing is that the neighboring cell selects a different carrier set in the same symbol frequency domain within the basic resource block to transmit the intermediate pilot, and the adjacent three cells The set of pilot carriers used within each basic resource block, Midamble — Ozm'er — Set — PR and the full-bandwidth intermediate pilot carrier physical location index set Midamble _ Carrier _ Set are:

Cell 1 uses a carrier set:

Midamble _ Carrier _ Set PRU = 3 + n + LAs;

Midamble _ Carrier _ Set = -(U )/2 + 18: + 3 + n + mod(^ ₂ ,m) *Δ?;

m

Cell 2 uses a carrier set:

Midamble _ Carrier _ Set PRU = 3 + n + k, As + A k

Midamble _ Carrier _ Set + 3 + n + mod(k ₂ ,m)*As + A m Cell 3 uses carrier set:

Midamble _ Carrier _ Set PRU = 3 + n + LAs + 2A

Midamble Carrier Set -l)/2 + 18 ^: + 3 + n + mod k ₂ ,m ^ As -\- 2A _BS m where is the carrier of the intermediate pilot in the frequency domain of each basic resource block of the neighboring cell Room Interval.

The base station transmits a message through the broadcast control channel and/or the unicast control channel to inform the user terminal of the position of the intermediate pilot in the downlink frame.

The method according to claim 11, wherein the message includes at least one of the following information: whether the current superframe or frame transmits information of the measurement pilot, and the subframe index of the intermediate pilot in the frame. The intermediate pilot has a symbol index in the subframe and a boosting function corresponding to the intermediate pilot

The method according to claim 11, further comprising: the base station transmitting the intermediate pilot in a continuous T frame starting from the frame of the current message offset by the AS frame, and transmitting the intermediate pilot in a periodic T frame, and The subframes corresponding to the intermediate pilots are transmitted through the broadcast control channel and/or the unicast control channel to notify the subframe index to which the intermediate pilot symbols belong, where AS, S, and T are natural numbers.

14. The method according to claim 11, wherein the message sent by the unicast control channel is a non-specific user control message of a downlink frame.

The method according to claim 11, wherein the method further comprises: when the number of antennas is 2 or 4:

The base station transmits the intermediate pilot on the third or fourth or seventh symbol in the downlink subframe; and determines the relative position of the intermediate pilot carrier corresponding to the w + 1 antenna (0 ≤ w ≤ 3) within the basic resource block. Index set Midamble _ Carrier_ Set — PRU ^

Midamble _ Carrier _ Set _ PR U = 3 + n + k^As;

+ 3 + + mod ( ₂ , ) * Ay;

And, when the intermediate pilot is inserted on a part of the resource block on the full bandwidth, occupying the physical carrier position, the Imiamble_Carrier_Set is:

Midamble Carrier Set =S, + n + 2 + mod k ₂ ,m)*As; and, when the number of antennas is 8,

The base station transmits the intermediate pilot on the third and fourth symbols in the downlink subframe;

And determining that the w + 1 antenna ( 0 ≤ w ≤ 7) corresponds to the intermediate pilot carrier relative position index within the basic resource block and the Midamble-Carrier-Set-PRU and the full-bandwidth intermediate pilot carrier physical position The collection Midamble _ Carrier-Set is:

Midamble Carrier Set PRU =3 +

Or, Midamble _ Carrier _ Set _ PRU = 3 + mod (n, ) + k^s;

Midamble _ Carrier _Set =-( N _used - 1 ) / 2 + 18 ^: + 3 + + mod k ₂ ,m)* As

Or for:

k,

Midamble _ Carrier _Set =-( N _med -l)/2 + 18 ^: + 3 + mod(n,4) + mod(^ ₂ ,m) m and, when the intermediate pilot is inserted on some resource blocks over the full bandwidth , occupy the physical carrier position? I Midamble _ Carrier _ Set is:

Midamble Carrier Set =S, + n + 2 + mod k ₂ ,m)*As; where A^CA—I is the index of the intermediate pilot on the basic resource block; indicating that each antenna is within one resource block The number of intermediate pilots inserted; =0,1,2^, _1, for each The index of the intermediate pilot of the antenna over the full bandwidth; indicates the number of intermediate pilots inserted by each antenna over the system bandwidth; the number of intermediate pilots within each basic resource block for each antenna; adjacent for each antenna The number of carrier intervals between two pilots; indicates the minimum number less than or equal to; N „^ indicates the number of all remaining subcarriers after the system removes the guard interval subcarriers; S,. indicates the first resource block inserted into the intermediate pilot. The physical location index corresponding to the first subcarrier, {0, 1, 2, is the basic resource block index set to which the intermediate pilot needs to be inserted; 0 ≤ "≤ 7.

The method according to claim 11, wherein the method further comprises: selecting, by a neighboring cell, the same subframe of different frames, or different subframes of the same frame, or sending on different symbols of the same subframe Intermediate pilot

The method according to claim 16, wherein the frequency division multiplexing is to transmit an intermediate pilot to a different carrier set in a same symbol frequency domain in a neighboring cell selection basic resource block, and three adjacent cells are used. The set of pilot carriers used within each basic resource block, Midamble — Ozm'er — Set — PR and the full-bandwidth intermediate pilot carrier physical location index set Midamble _ Carrier _ Set are:

Cell 1 uses a carrier set:

Midamble _ Carrier _ Set _ PRU = 3 + n + k, As; k,

Midamble _ Carrier _ Set = - ( N _used - l) / 2 + 18 ^: + 3 + + mod ( ₂ , ) * Ay; m

Cell 2 uses a carrier set:

Midamble _ Carrier _ Set _ PRU = 3 + n + k^As + Δ Midamble— Carrier— Set = -, N _used - l)/ 2 + 18 ^: + 3 + n + mod (k ₂ , m) * As + A m Cell 3 uses carrier set:

Midamble _ Carrier _ Set _ PRU = 3 + n + k, As + 2Δ k

Midamble _ Carrier _ Set = - ( N _used - l) / 2 + 18 ^: + 3 + n + mod(k ₂ , m) * As + 2A m where is the inner pilot of each basic resource block in the adjacent cell Carrier spacing in the frequency domain.

18. A method for transmitting a downlink intermediate pilot in a wireless communication system, comprising:

The base station transmits the intermediate pilot in one or more subframes except the first subframe in the downlink frame; or, the base station transmits the intermediate pilot in one downlink subframe of the downlink superframe except one subframe other than the first subframe.

The method according to claim 18, wherein the base station sends an intermediate pilot in a last downlink subframe in a downlink frame; or, the base station sends in a last subframe of a downlink frame of a downlink superframe. Intermediate pilot.

The method according to claim 18, wherein the method further comprises: when the terminal accesses, the base station notifies the terminal by transmitting the downlink subframe position of the intermediate pilot by using the access control related message.

The method according to claim 18, wherein the method further comprises: the base station transmitting a message by using a broadcast control channel and/or a unicast control channel to notify the terminal whether the current superframe and/or the frame sends the intermediate pilot, When transmitting, the base station transmits an intermediate pilot on the determined downlink frame and/or subframe.

22. The method according to claim 18, wherein the method further comprises: The base station transmits the intermediate pilot on the third or fourth or seventh symbol in the downlink subframe; and determines the relative position of the intermediate pilot carrier corresponding to the w + 1 antenna (0 ≤ w ≤ 3) within the basic resource block. Index set Midamble _ Carrier_Set—PRU is Midamble _ Carrier _ Set _ PRU = 3 + n + k^As;

When the intermediate pilot is inserted over the full bandwidth, occupying the physical carrier position index Carrier_Set is:

Midamble _ Carrier _Set =-( N _used -l)/2 + 18 ^: + 3 + n + mod(^ ₂ ,m) * A"; m and, when the intermediate pilot is inserted on a partial resource block over the full bandwidth, Occupying the physical carrier position, the cable I Midamble _ Carrier _ Set is:

Carrier Set =S, + n + 2 + mod (^ ₂ , m) * As; When the number of antennas is 8:

And determining that the w + 1 antenna (0 ≤ w ≤ 7) corresponds to the intermediate pilot carrier relative position index within the basic resource block, and the Midamble_Carrier_Set_PRU and the full-bandwidth intermediate pilot carrier physical location index set Midamble _ Carrier—Set is

Midamble Carrier Set PRU =3 +

Or, Midamble - Carrier - Set - PRU = 3 + mod (n, 4) + As; and when the intermediate pilot is inserted over the full bandwidth, occupying the physical carrier position index Carrier_Set is:

h

Midamble _ Carrier _Set =-( N _used - 1 ) / 2 + 18 : + 3 + + mod k ₂ ,m)* As m or, Midamble _ Carrier _Set =-( N _used - 1 ) / 2 + 18 :

And, when the intermediate pilot is inserted on a partial resource block over the full bandwidth, occupying the physical carrier position? I Midamble _ Carrier _ Set is:

Midamble— Carrier— Set =S, ^ | +n + 2 + mod k ₂ ,m)*As where = 0,1,2,... - 1 is the index of the intermediate pilot on the basic resource block; The number of intermediate pilots inserted by the antenna in a resource block; =0,1,2,... - 1, the index of the intermediate pilot for each antenna over the full bandwidth; indicating the middle of each antenna inserted in the system bandwidth The number of pilots; the number of intermediate pilots within each basic resource block for each antenna; the number of carrier spacing between two pilots adjacent to each antenna; indicates the minimum number less than or equal to; N„^ indicates the system The number of all subcarriers remaining after removing the guard interval subcarriers on both sides; S,. indicates the physical position index corresponding to the first subcarrier of the resource block inserted into the intermediate pilot, {0, 1, 2, which needs to be inserted into the intermediate guide The basic resource block index set of the frequency.

The method according to claim 18, wherein the method further comprises: selecting, by the neighboring cell, the same subframe of different frames, or different subframes of the same frame, or sending on different symbols of the same subframe Intermediate pilot

The method according to claim 23, wherein the frequency division multiplexing refers to that the neighboring cell selects a different carrier set in the same symbol frequency domain within the basic resource block to transmit the intermediate pilot, and the adjacent three a set of pilot carriers used within each basic resource block of a cell, Midamble — Ozm′er — Set — PR and a full-bandwidth intermediate pilot carrier physical location index set ― Carrier _ Set is: Cell 1 uses carrier set:

Midamble _ Carrier _ Set _ PRU = 3 + n + k^As

Midamble _ Carrier _Set =-( N _used - 1 ) / 2 + 18 : + 3 + n + mod ,m)*As; m

Midamble Carrier PRU = 3 + n + LAs + A

Midamble _ Carrier _Set =-( N _used - 1 ) / 2 + 18 + 3 + n + mod(k ₂ ,m)*As + A m Cell 3 uses carrier set:

Carrier Set PRU =3 + n + k,As + 2A k

Midamble _ Carrier _Set =-( N _used - 1 ) / 2 + 18 + 3 + n + mod(k ₂ ,m)*As + 2A m where is the intermediate pilot frequency in each basic resource block of the neighboring cell Carrier between domains