WO2011075889A1

WO2011075889A1 - Method and apparatus for mapping data streams to resource block in wireless communication system

Info

Publication number: WO2011075889A1
Application number: PCT/CN2009/075866
Authority: WO
Inventors: 兰元荣; 梁生宝; 张�杰
Original assignee: 富士通株式会社
Priority date: 2009-12-23
Filing date: 2009-12-23
Publication date: 2011-06-30
Also published as: CN102640468A

Abstract

The invention provides a method and an apparatus for mapping data streams to the resource block. In which the method includes: mapping almost all the system symbol streams in the data streams to the resource elements where the channel estimation error is as small as possible in the resource block; mapping almost all the verification symbol streams in the data streams to the resource elements where the channel estimation error is as large as possible in the resource block. The method of the invention can reduce the block error rate, and reduces the retransmission times required for the correct detection.

Description

Method and device for mapping data stream to resource block in wireless communication system

The present invention relates to a wireless communication system, and in particular to a method and apparatus for mapping data streams to resource blocks in a wireless communication system. Background technique

Orthogonal Frequency Division Multiplexing (OFDM) is a high-speed transmission technique in a wireless environment that transforms high-speed serial data into multiple relatively low-speed parallel data and modulates different carriers. This parallel transmission system greatly expands the pulse width of the symbol and improves the performance against multipath fading. At present, multi-carrier wireless communication based on Orthogonal Frequency Division Multiplexing (OFDM) technology uniformly divides a frequency selective fading wideband channel into a plurality of frequency flat fading channels, and only requires a single tap frequency equalizer at the receiving end, thereby It greatly simplifies the equalization algorithm of the system receiver. On this basis, the Multiple Input Multiple Output (MIMO) technology utilizes the characteristics of the spatial channel to provide high data rate and large throughput and a larger communication distance. High spectrum utilization. Therefore, MIMO-OFDM technology will remain the key technology of the physical layer of wireless communication systems at present and for a long time to come. Applications for MIMO-OFDM technology are supported in Long Term Evolution (LTE) or Advanced Long Term Evolution (LTE-A) systems.

At present, the signal transmission process in the LTE system generally includes: the data stream passes through one or more encoders to obtain coding system bits, and after respective scrambling operations, the scrambled information bits are modulated into a signal such as QPSK by using a symbol modulator. The symbol constellation points of 16QAM, 64QAM, etc., obtain a modulated codeword stream. The modulated codewords are mapped to different layers via a layer mapper to obtain signals on multiple layers. The signal on the layer is converted to an N signal by a precoder, where N is the number of transmit antennas. The serial signal of each branch is remapped onto the time-frequency two-dimensional physical resource, and finally the OFDM signal generator generates a time domain signal on each antenna and transmits it to the physical channel via each transmitting antenna. The present invention will discuss the mapping of serial signals to time-frequency two-dimensional physical resources for each branch after precoding.

In order to facilitate efficient allocation of physical resources, a physical frame is usually divided into a plurality of subframes in the time domain, and is divided into a plurality of basic resource blocks (resource blocks) in the frequency domain. RB). For example, in the LTE standard, a 10 ms physical frame contains 10 subframes and 20 slots; each subframe contains 14 OFDM symbols in the time domain, and contains basic allocation resource blocks in units of 12 subcarriers in the frequency domain. The time-frequency resource block composed of 14 OFDM symbols in the time domain and 12 sub-carriers in the frequency domain is one RB, and the time-frequency resource block composed of one OFDM symbol in the time domain and one sub-carrier in the frequency domain is the smallest physical resource particle ( Resource element, RE

At present, in the pilot design of the transmit antenna of the MIMO-OFDM system, there is a problem of unevenness of estimation accuracy of each RE channel. However, in the prior art, when the data stream is mapped to the resource block, the accuracy of estimation of each RE channel is not considered. Uniformity, which affects the reliability of data transmission, how to map modulation symbols more efficiently to each RE becomes an important issue in system design. Summary of the invention

In view of the problems in the prior art, it is an object of the present invention to provide a method and apparatus for mapping data streams to resource blocks in a wireless communication system to improve signal transmission quality.

According to an aspect of the present invention, a data stream to resource block mapping method is provided, wherein the method comprises the steps of: substantially mapping a system symbol stream in the data stream to a channel estimation error in the resource block As small as possible on the resource particles; and substantially mapping the check symbol stream in the data stream to resource particles in the resource block where the channel estimation error is as large as possible.

According to another aspect of the present invention, there is provided a data stream to resource block mapping apparatus, wherein the apparatus comprises: a first mapping unit that substantially maps a system symbol stream in the data stream to the resource block The medium channel estimation error is on the resource particle as small as possible; and the second mapping unit basically maps the check symbol stream in the data stream to the resource particle in the resource block whose channel estimation error is as large as possible.

According to another aspect of the present invention, a computer readable program is provided, wherein, when the program is executed in a multiple input multiple output system, the program causes a computer to execute the above-described data stream to a resource in a wireless communication system The mapping method of the block.

According to another aspect of the present invention, a storage storing a computer readable program is provided The medium, wherein the computer readable program causes a computer to perform the above-described data stream to resource block mapping method in a multiple input multiple output system.

The data stream to resource block mapping method and device of the invention can effectively reduce the block error rate of data transmission and improve the reliability of data transmission.

In order to achieve the foregoing and related ends, the invention includes the features that are fully described hereinafter and are particularly pointed out in the claims. The following description and the annexed drawings are set forth in detail in detail However, these embodiments are merely illustrative of several of the various ways in which the principles of the invention may be employed. Other objects, advantages and novel features of the invention will become apparent from the Detailed Description. DRAWINGS

In the drawings, the same or corresponding technical features or components will be denoted by the same or corresponding reference numerals. among them:

FIG. 1 shows an example of a common pilot signal (CRS) pattern of one sector in an LTE system;

2a to 2d respectively show statistical distribution grayscale views of channel estimation errors of the 1-4 antennas of the CRS of FIG. 1 in the ITU-PB 3 km/h channel model;

3a to 3d are respectively a three-dimensional view corresponding to FIG. 2a to FIG. 2d;

4a to 4d respectively show statistical distribution grayscale views of channel estimation errors of the 1-4 antennas of the CRS of FIG. 1 under the ITU-VA 120 km/h channel model;

5a to 5d are respectively a three-dimensional view corresponding to FIG. 4a to FIG. 4d;

6 is a flow chart showing a method of mapping a data stream to a resource block according to an embodiment of the present invention;

7 is a flow chart showing a method of mapping a data stream to a resource block according to another embodiment of the present invention;

FIG. 8 is a flow chart showing a method of mapping data streams to resource blocks according to another embodiment of the present invention; FIG.

FIG. 9 is a flowchart showing a data flow to resource block mapping method according to another embodiment of the present invention; FIG. FIG. 10 is a block diagram showing an example of a data stream to resource block mapping apparatus of one embodiment of the present invention;

Figure 11 is a block diagram showing a simple structure of a base station or a transmitter in a user equipment in a wireless communication system. detailed description

The technical solutions in the embodiments of the present invention are clearly and completely described in the following with reference to the accompanying drawings in the embodiments of the present invention. It is obvious that the described embodiments are only a part of the embodiments of the present invention, but not all embodiments. All other embodiments obtained by a person of ordinary skill in the art based on the embodiments of the present invention without creative efforts are within the scope of the present invention.

It is also to be noted that, in order to avoid obscuring the invention by unnecessary detail, only the device structure and/or processing steps closely related to the solution according to the present invention are shown in the drawings, and are omitted. Other details that are not relevant to the present invention.

The problem to be solved by the present invention is that there is a phenomenon that the estimation accuracy of each RE channel is uneven in the pilot design of the wireless system, and the mapping method and device for the data flow to the resource block in the first transmission and the retransmission are designed to effectively Improve the reliability of system transmission, reduce the number of retransmissions required for correct detection and residual bit error rate.

The present invention will focus on the LTE system as an example to illustrate the mapping of data streams to resource blocks, but the present invention is not limited to the LTE system, and the present invention can be applied to existing MIMO systems (such as LTE and LTE-A systems) and later developed. The mapping of data streams to resource blocks in a MIMO system. Moreover, the data stream to resource block mapping method and apparatus of the present invention are not only suitable for uplink transmission but also for downlink transmission.

In the embodiment of the present invention, the mapping method of the data flow to the physical resource is determined based on the quality of the channel estimation performance on each RE of the resource block. The user equipment in LTE needs to perform channel estimation on the channels on all its data REs before demodulating the data. According to the pilot structure of LTE, the RE position of the channel estimation may be determined to be poor. In channel coding, system bits (or information bits) are more important than parity bits, so the present invention will REs with better channel estimation accuracy are used to transmit systematic bit-modulated symbols, but for channels The RE that is estimated to be less effective is used to transmit the symbols of the check bit modulation. During the retransmission process, the transmitted symbols are mapped as much as possible to the channel estimation error different from the previously transmitted RE in order to obtain the effect of diversity and improve the efficiency of retransmission. For example, in the retransmission, the symbol in the RE with the better channel estimation effect is transmitted by the RE in the channel estimation effect, and the symbol in the RE with the poor channel estimation effect is used in the channel estimation. Transmitted in a better RE.

FIG. 1 is an example of a common reference signal (CRS) pattern (which may be referred to as a pilot pattern) of a sector in an LTE system. The horizontal axis direction in Fig. 1 represents different OFDM symbols, and the vertical axis represents different subcarriers.

Since the channel estimation statistical error distribution obtained under different channel model conditions may be different, it is necessary to consider the channel estimation error performance under different channel models to increase the applicability based on the method. The ITU-PB 3km/h channel model and the ITU-VA 120km/h channel model are two typical channel models with some representativeness. 2a to 2d respectively show statistical distribution diagrams of channel estimation errors of the 1-4 antennas of the CRS in FIG. 1 under the ITU-PB 3 km/h channel model, showing the first under the ITU-PB 3 km/h channel model. The statistical results of the channel estimation of the -4 antennas, the horizontal and vertical axes of Figures 2a to 2d have the same meaning as Figure 1. Figures 3a to 3d are three-dimensional views corresponding to Figures 2a to 2d, respectively. 4a to 4d respectively show statistical distribution diagrams of channel estimation errors of the 1-4 antennas of the CRS in FIG. 1 under the ITU-VA 120 km/h channel model, showing the first under the ITU-VA 120 km/h channel model. - Statistical results of channel estimation for 4 antennas. Figures 5a to 5d are three-dimensional views corresponding to Figures 4a to 4d, respectively. The meanings of the horizontal and vertical axes in Figures 4a to 4d are the same as in Figure 1.

Here, the algorithm used by the mobile station for channel estimation is, for example, a 2-dimensional minimum mean square error (2D MMSE) based on a resource block (RB). The channel estimates on any of the resource blocks are: _

The channel estimation mean square error is:

Here, ^ and ^ are the jth OFDM symbols of the i-th subcarrier in a certain resource block. The estimated value and the true value of the channel response on the channel are the column vectors arranged for the channel response of all the pilot points in the resource block, which is an interpolation vector using the 2D MMSE criterion. The above channel estimation algorithm is not limited to the 2D MMSE criterion, and other linear interpolation methods may be used. The form of the channel estimation is exactly the same as (1), except that the element values of the .

The resource mapping method of the embodiment of the present invention is described below based on the channel estimation statistical characteristics under different channel models.

FIG. 6 is a diagram showing a method for mapping a data stream to a resource block in a wireless communication system according to an embodiment of the present invention, the method comprising the following steps:

Step S110: Basically map the system symbol stream in the data stream to resource particles in the resource block with the channel estimation error as small as possible.

For example, the system symbol stream in the data stream may be mapped to the preceding plurality of REs according to the channel estimation error of the REs in the resource block from small to large, and the number of the plurality of REs corresponds to the system symbol stream. length. The maximum channel estimation error corresponding to the preceding plurality of REs will be less than or equal to the smallest channel estimation error corresponding to the remaining REs. The remaining REs will be used to transmit the check symbols.

Step S130: Basically map the check symbol stream in the data stream to resource particles in the resource block whose channel estimation error is as large as possible.

For example, a check symbol stream can be mapped to the remaining REs.

For convenience of description, a plurality of REs in a resource block for transmitting a system symbol stream may be referred to as a first group of REs, and the remaining REs in the resource block for transmitting a check symbol stream are referred to as a second group of REs.

It should be noted that, in the embodiment of the present invention, it is not necessary to very strictly require that the channel estimation error of each RE in the first group of REs is less than or equal to the channel estimation error of each of the second groups of REs. Sometimes, in order to be simpler to implement, the channel estimation error of an individual or a very small number of REs in the first group of REs may be allowed to be slightly larger than the channel estimation error of a small number of REs in the second group of REs, as long as most system symbols are guaranteed. The flow is mapped to the RE of the resource block whose channel estimation error is small, so that the transmission reliability of the data stream can be improved relative to the prior art. Therefore, in the mapping method corresponding to Fig. 1, the expression "basic mapping to ..." is adopted in steps S110 and S130.

The first set of REs may form an area in a resource block. In an embodiment of the invention Preferably, the largest channel estimation error in the region is less than or equal to the smallest channel estimation error outside the region, in other words, all REs in the region have smaller channel estimation errors, where "Smaller channel estimation error" refers to a channel estimation error that is less than or equal to the smallest channel estimation error of the RE outside the region. In another embodiment of the invention, preferably, the region comprises an RE having a minimum channel estimation error. In practical applications, the area may be predetermined based on the magnitude of the channel estimation error. The area may be an irregular area.

In addition, in another embodiment of the present invention, an area of a shape rule conforming to the length of the system symbol stream, such as a rectangular area, may be pre-selected in the resource block for convenience of implementation, so that the shape ruled area has as many as possible Resource particles with smaller channel estimation errors, referred to herein as "smaller channel estimation errors", satisfy: The channel estimation error is less than or equal to the smallest channel estimation error of the out-of-area RE of the shape rule.

In addition, in another embodiment of the present invention, an area of a predetermined size of a predetermined rule, such as a rectangular area, may be preselected in the resource block, and if the transmission capability of the area of the shape rule is inconsistent with the length of the system symbol stream, The area of the shape rule can be appropriately widened or contracted according to the length of the system symbol stream at the time of mapping.

When performing resource mapping on the antenna 1 based on the ITU-PB 3 km/h channel model in FIG. 2a and FIG. 3a, for example, the system symbol stream may be mapped in the RE corresponding to the antenna 1 in the RE of the antenna 1 with the channel estimation error as small as possible, or Mapping into a predetermined rectangular area such that there are as many resource particles as there are smaller channel estimation errors in the rectangular area, where the smaller channel estimation error is satisfied, and the channel estimation error is less than or equal to the rectangular area The smallest channel estimation error of the outer RE. The rectangular area may be, for example, an area determined by sub-carrier 5 and sub-carrier 6 and RE corresponding to symbol 5 to symbol 8 in the resource block shown in Figs. 2a and 3a. The predetermined rectangular regions described herein are merely examples and are not intended to limit the invention, and various other predetermined region shapes may exist within the spirit of the present invention.

When performing resource mapping based on the antenna 1 under the ITU-VA 120 km/h channel model in FIGS. 4a and 5a, for example, the system symbol stream can be mapped to channel estimates corresponding to subcarrier 5 and subcarrier 6 and symbols 6 and 7 The four REs with the smallest error are centered in the regular or irregular region of the system symbol stream length, so that all or most of the system symbol streams are Mapped on an RE with a small channel estimation error, where a smaller channel estimation error means that the channel estimation error is less than or equal to the RE outside the regular or irregular region (ie, the RE used to transmit the check symbol stream) The smallest channel estimation error.

For another example, when performing resource mapping based on the antenna 2 in the ITU-VA 120 km/h channel model in FIG. 4b and FIG. 5b, for example, the system symbol stream can be mapped on each RE of the region including the RE having the smallest channel estimation error. . This is just an example. You can also use the other mapping methods described above.

Based on the channel estimation error distributions of other antennas in FIGS. 2b-2d and 3b-3d and FIGS. 4c-4d and 5c-5d, the data streams corresponding to other antennas can be performed in the same manner as described above. The mapping to the corresponding resource block.

The above method of the present invention can effectively reduce the block error rate of data transmission.

Since the foregoing steps S110 and S130 can respectively have a plurality of different specific implementation manners, specific implementations thereof will be described below based on specific examples.

Although in the above description, each step is described in sequence, it should be clear that the order of the above steps is not fixed, and step S130 may be performed before step S1 10 or in parallel with step S110. get on.

In order to further reduce the residual block error rate and correctly detect the number of retransmissions required, an embodiment of the present invention also specifically transforms the mapping manner of the data stream to the resource block according to the statistical characteristics of the channel estimation during retransmission, The transmitted symbols are mapped as much as possible to the channel estimation error that is different from the previously transmitted RE. Figure 7 shows the flow chart when the data retransmission mapping is included. The mapping method shown in FIG. 7 includes the following steps in addition to steps S110 and S130:

Step S150: When retransmitting the mapping, the system symbol stream in the data stream is basically mapped to the resource particles in the resource block with the channel estimation error as large as possible.

For example, the system symbol streams in the data stream may be mapped to the preceding plurality of REs in descending order of the channel estimation errors of the REs in the resource blocks, the number of the plurality of REs corresponding to the length of the system symbol stream.

Step S170: Basically map the check symbol stream in the data stream to resource particles in the resource block whose channel estimation error is as small as possible.

For example, a check symbol stream can be mapped to the remaining REs. The foregoing steps S150 and S170 are merely examples, and are not intended to limit the present invention. Other retransmission mapping modes exist, and steps S150 and S170 may also have different specific implementation manners respectively, and the following may also be based on specific An example is given for explanation.

Figure 8 is a specific example flow of mapping a data stream to a resource block in accordance with one embodiment of the present invention. As shown in Figure 8, the process includes:

Step S210: Mapping the system symbol stream to the resource particles in the first region of the resource block that is substantially centered on the resource particles with the smallest channel estimation error.

Step S230: Mapping a check symbol stream to resource particles outside the first area in the resource block.

Before performing step S210, the first region may be predetermined based on resource particles having the smallest channel estimation error. The first region may not be determined in advance, but the system symbol stream may be directly mapped to the resource according to the channel estimation error of the resource particle from the smallest to the largest, starting from the resource particle with the smallest channel estimation error in this step S210. The RE of the block, thereby forming the first region, at which time the maximum channel estimation error of the RE in the first region is less than or equal to the smallest channel estimation error of the RE outside the first region.

If the first area is predetermined before step S210. There are a plurality of methods for predetermining the first region, and several methods for determining are listed below:

Mode 1, selecting a first region suitable for the length of the system symbol stream from the resource blocks according to a size of a channel estimation error of each resource particle, such that a maximum channel estimation error in the first region is less than or equal to the The smallest channel estimation error outside the first region, that is, all REs in the first region have smaller channel estimation errors, where "smaller channel estimation error" means less than or equal to the first The channel estimation error of the smallest channel estimation error of the RE outside the region.

With this method, the first region can be selected conveniently for the channel estimation results corresponding to FIGS. 2a-2d and 3a-3d and FIGS. 4a-4d and 5a-5d, for example for FIG. 4a and FIG. 5a. In the channel estimation result, an irregular region conforming to the system symbol stream length centered on the four REs having the smallest channel estimation error corresponding to the subcarriers 5 and 6 and the symbols 6 and 7 can be selected.

Mode 2: Determine the suitable system symbol stream centering on the resource particles with the smallest channel estimation error The first region of a length and having a regular shape.

The regular shape may be, for example, a rectangle (including a square), and may be other axisymmetric or centrosymmetric figures.

At this time, all REs in the first region do not necessarily have a small channel estimation error with respect to each RE outside the first region, but for a certain shape, the first region should have as many as possible Smaller channel estimation error RE.

With this approach, for example, between subcarrier 1 and subcarrier 10 (including subcarrier 1 and subcarrier 10) and between symbol 1 and symbol 10 (including symbol 1 and symbol 10) can be selected based on the channel estimation errors in Figures 4c and 5c. The area is the first area, and it is assumed here that the size of the selected first area conforms to the length of the system symbol stream.

Mode 3: Determine a predetermined size and regular shape area centering on resource particles with the smallest channel estimation error, wherein the predetermined size does not necessarily match the length of the system symbol stream.

Here, the regular shape may be, for example, a rectangle (including a square), and may be other axisymmetric or centrosymmetric patterns.

At this time, the first area is obtained by expanding or contracting the rectangular area in a predetermined direction based on the size of the system symbol stream at the time of mapping. The direction of expansion or contraction can be selected in advance.

For example, with this approach, for example, a rectangular region of 14 symbols between subcarrier 3 and subcarrier 8 (including subcarrier 3 and subcarrier 8) can be selected based on the channel estimation error of the corresponding antenna 4 in Figs. 2d and 3d. It is assumed here that the size of the selected rectangular area is larger than the length of the system symbol stream.

Then, when mapping is performed, the predetermined rectangle may be contracted according to the length of the system symbol stream to be between subcarrier 3 and subcarrier 8 (including subcarrier 3 and subcarrier 8) and between symbol 1 and symbol 12 (including symbol 1 and The area between the symbols 12) and the area as the first area.

The above first area determination manner is merely an example, and other determination manners are not excluded.

By using S210 and S230 in Figure 8, the block error rate of data transmission can be effectively reduced, and the performance of transmission can be improved.

In addition, when data stream retransmission is required, the retransmission mapping is performed based on the following steps: Step S250: When the data stream is retransmitted, the check symbol stream is mapped to the resource block. The resource particle in the second region centered on the resource particle with the smallest channel estimation error.

In this step, the second region may be determined in the same manner as the first region, except that the size of the second region is adapted to the length of the check symbol stream, and the transmission capability and check symbol of the second region are The amount of data in the stream is consistent.

Step S270: Map the system symbol stream to resource particles outside the second region in the resource block.

In the retransmission mapping method shown in S250 and S270, the system symbol stream and the check symbol stream are all or incompletely reversed in the position in the resource block. When the lengths of the system symbol stream and the check symbol stream are the same, the position of the system symbol stream and the check symbol stream in the resource block can be completely reversed. When the lengths of the system symbol stream and the check symbol stream are different, the positions of the system symbol stream and the check symbol stream in the resource block may be incompletely reversed, that is, partially reversed.

The mapping scheme corresponding to FIG. 8 not only reduces the error block rate that can be transmitted for the first time, but also transforms the mapping mode according to the statistical characteristics of the channel estimation in the retransmission, increases the diversity gain, and reduces the residual error block rate. And the number of retransmissions required for proper detection.

The above steps S250 and S270 are only examples of the retransmission mapping manner, and other methods are not excluded. Steps S350 and S370 of Fig. 9 show another different retransmission mapping manner. In Fig. 9, steps S310 and S330 are the same as steps S210 and S230, and are not described in detail herein, but only steps S350 and S370 are explained.

Step S350: When retransmitting the mapping, mapping the system symbol stream to the resource particles in the first region according to a mapping order opposite to the initial transmission, to change the location of the system symbol in the first region.

Here, the reverse mapping order described above refers to the positional order of the system symbol and the RE.

The method may further include: dividing the first area into a first sub-area (such as area A) and a second sub-area (such as area B), and mapping to the area A when the data stream is initially transmitted. The system symbol stream in the map is mapped to the region B at the time of retransmission, wherein the channel estimation error of the resource particles in the first sub-region is smaller than the channel estimation error in the second sub-region.

If the sizes of the area A and the area B are not the same, the system symbol stream in the area A may be partially adjusted to the area B, or the system symbol stream in the area B may be retransmitted when the mapping is retransmitted. Partially adjusted to area A.

Step 370: Map the check symbol stream to resource particles outside the first area in the resource block according to a mapping order opposite to the initial transmission, to change the area outside the first area The position of the check symbol.

The specific implementation method can be the same as step 350 above.

The retransmission mapping step in Figure 9 keeps the area of the system symbol stream and the check symbol stream unchanged during retransmission. In each area, the system symbol stream and the check symbol stream are remapped separately.

In the foregoing embodiments, the mapping relationship between the system symbol stream and the check symbol stream and different areas in the resource block is introduced. The mapping order in the respective areas will be described below.

List several mapping sequences as follows:

(1) When the system symbol stream and the check symbol flow are mapped to respective regions, the system symbol stream and the check symbol stream may be sequentially mapped to the respective symbols in the respective regions according to the index increment or decrement of the symbols in the respective regions. On each resource particle.

§卩, mapping one symbol to one symbol in each region. Wherein, when the system symbol stream and the check symbol stream are respectively mapped to the respective regions, the corresponding mapping order may be the same or different.

(2) When the system symbol stream and the check symbol stream are mapped to the respective regions, the system symbol and the check symbol stream may be sequentially mapped to the respective subcarriers in the respective regions according to the index number of the subcarriers in the respective regions from the increasing or decreasing order. On each resource particle.

§ 卩, one subcarrier is mapped one subcarrier in each region. Wherein, when the system symbol stream and the check symbol stream are respectively mapped to the respective regions, the corresponding mapping order may be the same or different.

(3) When the system symbol stream and the check symbol flow are mapped to the respective regions, the system symbol stream and the check symbol stream may be mapped to the respective regions according to the channel estimation error of the resource particles in the respective regions from small to large or small to small. On each resource particle inside.

§卩, mapping from inside to outside or from outside to inside in their respective regions. Wherein, when the system symbol stream and the check symbol stream are respectively mapped to the respective regions, the corresponding mapping order may be the same or different. The above method of the present invention is applicable not only to an LTE system but also to an LTE-A system, and is applicable to a system in which LTE and LTE-A coexist. When coexistence in multiple systems, such as LTE Rel-8 and LTE-A Rel-10 systems, since multi-antenna transmission in Rel-10 requires channel estimation for additional antennas, a puncturing operation is performed. When performing subcarrier mapping on the Rel-8 system, it is necessary to avoid mapping the system modulation symbols to the pilot positions of the Rel-10 antenna. When the system symbol stream and the transmitted RE position of the check symbol stream are reversed, it is also avoided to map the system modulation symbols to the pilot positions of the Rel-10 antenna to prevent important data from being destroyed.

In general, in mapping a system symbol stream in the data stream to a resource particle having a small channel estimation error, avoid mapping the system modulation symbol in the system symbol stream to the multi-system coexistence mode The pilot position in the resource block structure corresponding to each system.

The mapping method of the present invention, which is described above and which will be described later, may be implemented on the network side, such as in a base station, a base station controller, and a relay station, or in a user equipment. Specifically, each of the foregoing mapping methods may be implemented in a resource mapper of a transmitter on the network side and the user equipment side.

11 is a schematic diagram showing a simple structure of a base station or a transmitter in a user equipment in a wireless communication system. In FIG. 11, a scrambler is used to scramble the encoded information bits, for example, to encode information bits with a specific one. The binary sequence is summed and then modulo 2 is operated. A symbol modulator is used to modulate the scrambled information bits into symbol constellation points such as QPSK, 16QAM, 64QAM, and the like. The module codeword to layer mapper maps the codeword stream output by the respective encoders to different layers to obtain signals on multiple layers. The precoder is used to convert the signal on the layer into n signals, where n is the number of transmit antennas. The physical resource mapper is configured to map the serial signal of each branch to the time-frequency two-dimensional physical resource, and the OFDM signal generator is configured to generate a time domain signal on each antenna by using a signal on the time-frequency two-dimensional physical resource and The respective transmit antennas are sent to the physical channel.

The present invention provides an improvement to the existing physical resource mapper, and proposes a new physical resource mapper, which is set in a transmitter in a base station or a relay station, and can also be set in a user equipment. In the transmitter. As shown in FIG. 10, the physical resource mapper includes a mapping unit 420, configured to map a data stream to a resource block at the time of initial transmission, and the mapping unit 420 further includes: A first mapping unit 421 that substantially maps a system symbol stream in the data stream to resource particles in the resource block with a channel estimation error as small as possible. For example, the first mapping unit 421 can map the system symbol stream in the data stream to each RE in the first region of the resource block that contains the RE with the smallest channel estimation error. Wherein all the REs in the first region have a smaller channel estimation error, where the smaller channel estimation error is satisfied, and the smaller channel estimation error is less than or equal to the minimum of the RE outside the first region. Channel estimation error.

A second mapping unit 422 that substantially maps the check symbol stream in the data stream to resource particles in the resource block where the channel estimation error is as large as possible. For example, the second mapping unit 422 can be configured to map the check symbol stream onto the RE outside of the first region.

In another embodiment of the present invention, the physical resource mapper further includes a remapping unit 430 for performing remapping of the data stream to the resource block. As shown in FIG. 10, the remapping unit 430 further includes:

A first remapping unit 431 that substantially maps the system symbol stream in the data stream to resource particles in the resource block where the channel estimation error is as large as possible during retransmission.

A second remapping unit 432 that substantially maps the check symbol stream in the data stream to resource particles in the resource block where the channel estimation error is as small as possible.

In another embodiment of the present invention, the first mapping unit 421 is configured to map the system symbol stream to resource resources in a first region of a resource block that is substantially centered on resource particles with the smallest channel estimation error. .

The second mapping unit 422 is configured to map the check symbol stream onto resource particles outside the first region in the resource block.

In another embodiment of the present invention, the first retransmission mapping unit 431 is configured to: when the data stream is retransmitted, map the check symbol stream to the resource block in the resource block that is substantially the smallest channel estimation error. On the resource particles in the second area of the center. The determining manner of the second area may be the same as the determining manner of the first area, except that the size of the second area is adapted to the length of the check symbol stream, and the transmission capability and the check symbol stream of the second area are The amount of data is consistent.

The second retransmission mapping unit 432 is further configured to map the system symbol stream to resource particles outside the second region in the resource block when the data stream is retransmitted. In another embodiment of the present invention, the first retransmission mapping unit 431 is further configured to: when the data stream is retransmitted, map the system symbol stream into the resource block according to a mapping order opposite to the initial transmission, and substantially estimate the channel. The resource particle with the smallest error is on the resource particle in the first region of the center to change the position of the system symbol in the first region. For example, dividing the first area into a first sub-area (such as area A) and a second sub-area (such as area B), and mapping the system symbol stream in area A when the data stream is initially transmitted is heavy. The time-transfer is mapped to region B, wherein the channel estimation error of the resource particles in the first sub-region is smaller than the channel estimation error in the second sub-region. If the sizes of the area A and the area B are not the same, the system symbol stream in the area A may be partially adjusted to the area B when the mapping is retransmitted, or the system symbol stream in the area B may be partially adjusted to the area A. .

The second retransmission mapping unit 432 is further configured to, when the data stream is retransmitted, map the check symbol stream to resource particles outside the first region in the resource block according to a mapping order opposite to the initial transmission. Upper to change the position of the check symbol in the area outside the first area.

In another embodiment of the present invention, as shown in FIG. 10, the physical resource mapper further includes: an area selecting unit 410, selecting a suitable location from the resource block according to a size of a channel estimation error of each resource particle. The first region of the size of the system symbol stream is such that a maximum channel estimation error in the first region is less than or equal to a minimum channel estimation error outside the first region. The region selection unit 410 may also determine the second region based on various manners of determining the first region as described above.

In another embodiment of the present invention, the area selection unit determines a rectangular area of a predetermined size centering on resource particles having the smallest channel estimation error; wherein the first area is based on a size of the system symbol stream The rectangular area is expanded or contracted in a predetermined direction.

In another embodiment of the present invention, the first mapping unit 421 further sequentially maps the system symbol stream to each symbol in the first area according to an order in which the index numbers of the symbols in the first area are incremented or decremented. The second mapping unit 422 further sequentially maps the check symbol stream to each resource particle of each symbol outside the first region in an order that the index number of the outer symbol of the first region is incremented or decremented. . That is, the first mapping unit 421 and the second mapping unit 422 perform one symbol and one symbol in the respective regions. Mapping. Wherein, when the system symbol stream and the check symbol stream are respectively mapped to the respective regions, the corresponding mapping order may be the same or different.

In another embodiment of the present invention, the first mapping unit 421 sequentially maps the system symbol streams to the subcarriers in the first region in an order of increasing or decreasing according to the index number of the subcarriers in terms of mapping order. The second mapping unit 422 sequentially maps the check symbol stream to the respective resources of each subcarrier outside the first area in order of increasing or decreasing in accordance with the index number of the subcarrier in terms of mapping order. On the particle. That is, the first mapping unit 421 and the second mapping unit 422 map one subcarrier by one subcarrier in each region. Wherein, when the system symbol stream and the check symbol stream are respectively mapped to the respective regions, the corresponding mapping order may be the same or different.

In another embodiment of the present invention, the first mapping unit 421 further maps the system symbol stream to the order of the channel estimation error of the resource particles in the first region from small to large or small to small in order of mapping order. Each of the resource particles in the first region; the second mapping unit 422 further checks the symbol stream according to the channel estimation error of the resource particles outside the first region in order of mapping order from small to large or small to large in order of mapping order. Mapping to each resource particle outside the first region. That is, the first mapping unit 421 and the second mapping unit 422 are mapped from inside to outside or from outside to inside in respective areas. Wherein, when the system symbol stream and the check symbol stream are respectively mapped to respective regions, the corresponding mapping order may be the same or different.

The first remapping unit 431 and the second remapping unit 432 in the remapping unit 430 may perform system symbol flow and check symbols based on the same or different mapping order as the first mapping unit 421 and the second mapping unit 422. The mapping to the resource block.

In another embodiment of the present invention, the first mapping unit further avoids mapping system modulation symbols in the system symbol stream to pilot positions in resource block structures corresponding to systems in the multi-system coexistence mode, thereby preventing important data. It is knocked out when punched.

It will be understood that two or more of the elements of the apparatus described herein may be combined into one unit, and each unit may be further subdivided into a plurality of sub-units without affecting the implementation of the present invention.

And it should be understood that the various parts of the above described invention may be implemented by hardware, software, The firmware or a combination of them is implemented. In the above-described embodiments of the present invention, a plurality of steps or methods may be implemented by software or firmware stored in a memory and executed by a suitable instruction execution system.

Any process or method description or block in the flowcharts or otherwise described herein can be understood as a module representing code that includes one or more executable instructions for implementing a particular logical function or step in a process. And a fragment, or a portion, and the scope of the preferred embodiments of the invention includes additional implementations, which may not be in the order shown or discussed, including in a substantially simultaneous manner or in reverse order depending on the functionality involved. The function is performed, which should be understood by those skilled in the art of the present invention.

The logic and/or steps represented in the flowchart or otherwise described herein, for example, may be considered as an ordered list of executable instructions for implementing logical functions, and may be embodied in any computer readable medium. And for use in an instruction execution system, apparatus, or device (such as a computer-based system, a system including a processor, or other system that can fetch instructions from an instruction execution system, apparatus, or device and execute instructions), or in conjunction with such instruction execution systems, Used for devices or equipment. For the purposes of this specification, a "computer-readable medium" can be any apparatus that can contain, store, communicate, propagate, or transport a program for use in an instruction execution system, apparatus, or device, or in conjunction with such an instruction execution system, apparatus, or device. The computer readable medium can be, for example, but not limited to, an electronic, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, device, or propagation medium. More specific examples of computer readable media (non-exhaustive list) include the following: electrical connections (electronic devices) with one or more wires, portable computer disk cartridges

(magnetic device), random access memory (RAM) (electronic device), read only memory (ROM) (electronic device), erasable programmable read only memory (EPROM or flash memory) (electronic device), optical fiber ( Optical device), and portable compact disk read only memory (CDROM) (optical device). In addition, the computer readable medium may even be a paper or other suitable medium on which the program can be printed, as it may be optically scanned, for example by paper or other medium, followed by editing, interpretation or, if appropriate, other suitable The method proceeds to obtain the program electronically and then store it in computer memory.

The above description and drawings show various features of the invention. It should be understood that one of ordinary skill in the art can prepare suitable computer code to implement the above description and The various steps and processes illustrated in the figures. It should also be understood that the various terminals, computers, servers, networks, etc. described above can be of any type and that the computer code can be prepared in accordance with the disclosure to implement the present invention with the device.

Although specific features of the present invention have been described above with respect to only one or more of the several illustrated embodiments, such features may be combined with others as desired and in terms of advantages for any given or specific application. One or more other features of the embodiments are combined. Finally, it is also to be understood that the terms "comprising", "comprising", or any other variants are intended to encompass a non-exclusive inclusion, such that the process, method, item, or It also includes other elements that are not explicitly listed, or elements that are inherent to such a process, method, item, or device.

The embodiments of the present invention have been described in detail above with reference to the accompanying drawings. Various modifications and changes may be made to the above-described embodiments without departing from the spirit and scope of the invention. Therefore, the scope of the invention is to be limited only by the appended claims and their equivalents.

Claims

Rights request

A data stream to resource block mapping method, where the method includes the following steps: mapping a system symbol stream in the data stream to a resource particle having a channel estimation error as small as possible in the resource block;

The check symbol stream in the data stream is substantially mapped to resource particles in the resource block where the channel estimation error is as large as possible.

2. The method according to claim 1, wherein the method further comprises the steps of: substantially mapping a system symbol stream in the data stream to a channel estimation error in the resource block when the data stream is retransmitted As large as possible on the resource particles;

The check symbol stream in the data stream is substantially mapped onto resource particles in the resource block where the channel estimation error is as small as possible.

3. The method of claim 1 wherein:

Mapping the system symbol stream in the data stream to the resource particles in the resource block with the channel estimation error as small as possible includes: mapping the system symbol stream into the resource block, and the resource particle having the smallest channel estimation error is Mapping the resource stream in the first region of the center; and mapping the check symbol stream in the data stream to the resource particles in the resource block where the channel estimation error is as large as possible: including: mapping the check symbol stream Going to resource particles outside the first region in the resource block.

The method according to claim 3, wherein the method further comprises the following steps: mapping, when the data stream is retransmitted, mapping the check symbol stream to the resource block with a channel estimation error being the smallest a resource particle within a second region centered on the resource particle; and mapping the system symbol stream to resource particles outside the second region of the resource block.

5. The method according to claim 3, wherein the method further comprises: when the data stream is retransmitted, mapping the system symbol stream into the resource block according to a mapping order opposite to the initial transmission, substantially using channel estimation error The smallest resource particle is centered on the resource particle in the first region to change the position of the system symbol in the first region; and/or

When the data stream is retransmitted, the check symbol is mapped in the reverse mapping order as the initial transmission. Shooting onto resource particles outside the first region in the resource block to change a location of the check symbol in a region outside the first region.

6. The method according to claim 5, wherein the mapping of the system symbol stream to a resource block in a first region centered on a resource particle having a smallest channel estimation error is mapped in a mapping order opposite to the initial transmission. The resource particle includes: dividing the first area into a first sub-area and a second sub-area, and mapping the system symbol stream in the first sub-area when the data stream is initially transmitted, at the time of retransmission Mapping to the second sub-area, wherein a channel estimation error of resource particles in the first sub-area is smaller than a channel estimation error in the second sub-area.

The method according to claim 3, wherein the method further comprises: selecting, according to a size of a channel estimation error of each resource particle, the first region suitable for a size of the system symbol stream from the resource block. And causing a maximum channel estimation error in the first region to be less than or equal to a minimum channel estimation error outside the first region.

8. The method according to claim 3, wherein the method further comprises: determining the first region of a predetermined size centering on resource particles having the smallest channel estimation error.

The method according to claim 3, wherein the method further comprises: determining a rectangular area of a predetermined size centering on resource particles having the smallest channel estimation error; wherein the first area is based on the system symbol stream The size is obtained by expanding or contracting the rectangular area in a predetermined direction.

10. The method of claim 3, wherein:

Mapping the system symbol stream to the resource particle in the first region of the resource block, which is substantially centered on the resource particle with the smallest channel estimation error, includes: the system symbol is increased or decreased according to the index number of the symbol in the first region The stream is sequentially mapped onto each resource particle of each symbol in the first area;

Mapping the check symbol stream to the resource particles outside the first area in the resource block includes: mapping the check symbol stream to the order in which the index number of the outer symbol of the first area is incremented or decremented On each resource particle of each symbol outside the first area.

11. The method of claim 3, wherein:

Mapping system symbol streams to resource particles in resource blocks that are roughly the smallest channel estimation error Included on the resource particles in the first region that is centered: sequentially mapping system symbol streams to respective resource particles of each subcarrier in the first region according to an index number of subcarriers in the first region from increasing or decreasing order on;

Mapping the check symbol stream to the resource particles outside the first area in the resource block includes: sequentially, according to the index number of the outer subcarriers of the first area, the check symbol stream is sequentially updated or decremented Mapping to each resource particle of each subcarrier outside the first area.

12. The method of claim 3, wherein:

Mapping the system symbol stream to the resource particles in the first region of the resource block, which is substantially centered on the resource particles with the smallest channel estimation error, includes: obtaining, according to the channel estimation error of the resource particles in the first region, from small to large A small sequence maps a system symbol stream to each resource particle in the first region;

Mapping the check symbol stream to the resource particles outside the first region in the resource block includes: verifying that the channel estimation error of the resource particles outside the first region arrives from small to large or small to small The symbol stream is mapped onto each resource particle outside the first region.

13. The method according to any one of claims 1 to 12, wherein in the step of substantially mapping a system symbol stream in the data stream to a resource particle having a small channel estimation error, avoiding The system modulation symbols in the system symbol stream are mapped to resource particles that need to be exclusive to another system when multiple systems coexist.

14. A mapping device for data stream to a resource block, wherein the device comprises: a first mapping unit that substantially maps a system symbol stream in the data stream to a resource with a channel estimation error as small as possible in the resource block On the particle;

A second mapping unit that substantially maps the check symbol stream in the data stream to resource particles in the resource block where the channel estimation error is as large as possible.

15. The apparatus according to claim 14, wherein the apparatus further comprises: a first remapping unit that substantially maps a system symbol stream in the data stream to a channel estimate in the resource block when retransmitting As large as possible on the resource particles; and

A second remapping unit that substantially maps the check symbol stream in the data stream to resource particles in the resource block whose channel estimation error is as small as possible.

16. Apparatus according to claim 14 wherein: The first mapping unit is further configured to map the system symbol stream onto resource particles in a first region of the resource block that is substantially centered on resource particles with the smallest channel estimation error; and the second mapping unit further And for mapping the check symbol stream onto resource particles outside the first region in the resource block.

The apparatus according to claim 16, wherein the apparatus further comprises: a first retransmission mapping unit that maps the check symbol stream to the resource block when a data stream is retransmitted Medium on a resource particle in a second region centered on resource particles with the smallest channel estimation error;

And a second retransmission mapping unit that maps the system symbol stream to resource particles outside the second region in the resource block when the data stream is retransmitted.

18. The apparatus according to claim 16, wherein the apparatus further comprises: a first retransmission mapping unit, when the data stream is retransmitted, mapping the system symbol stream to a mapping order opposite to the initial transmission to The resource block is substantially on the resource particle in the first region centered on the resource particle with the smallest channel estimation error to change the position of the system symbol in the first region; and/or

a second retransmission mapping unit, when the data stream is retransmitted, mapping the check symbol stream to resource particles outside the first region in the resource block according to a mapping order opposite to the initial transmission, To change the position of the check symbol in the area outside the first area.

The apparatus according to claim 16, wherein the apparatus further comprises: an area selecting unit that selects a size suitable for the system symbol stream from the resource block according to a size of a channel estimation error of each resource particle. The first region is such that a maximum channel estimation error in the first region is less than or equal to a minimum channel estimation error outside the first region.

The device according to claim 16, wherein the device further comprises: a region selecting unit that determines a rectangular region of a predetermined size centering on resource particles having the smallest channel estimation error;

The first area is obtained by expanding or contracting the rectangular area in a predetermined direction based on the size of the system symbol stream.

21. Apparatus according to claim 16 wherein: The first mapping unit further sequentially maps the system symbol stream to each resource particle of each symbol in the first region according to an order in which the index number of the symbol in the first region is incremented or decremented;

The second mapping unit further sequentially maps the check symbol stream to each resource particle of each symbol outside the first area in an order of increasing or decreasing the index number of the outer symbol of the first area.

22. Apparatus according to claim 16 wherein:

The first mapping unit further sequentially maps system symbol streams to respective resource particles of each subcarrier in the first region according to an index number of subcarriers in the first region from increasing or decreasing;

The second mapping unit further sequentially maps the check symbol stream to each resource particle of each subcarrier outside the first area in an increasing or decreasing order according to an index number of the outer subcarriers of the first area.

23. Apparatus according to claim 16 wherein:

The first mapping unit further maps the system symbol stream to each resource particle in the first region according to the channel estimation error of the resource particles in the first region from small to large or small to small;

The second mapping unit further maps the check symbol stream to each resource particle outside the first region according to the channel estimation error of the resource particles outside the first region from small to large or small to small.

The apparatus according to any one of claims 14 to 23, wherein the first mapping unit further avoids mapping system modulation symbols in a system symbol stream to resources that another system needs to monopolize when multiple systems coexist On the particle.

25. A computer readable program, wherein when the program is executed in a multiple input multiple output system, the program causes a computer to perform the multi-input multiple output system according to any one of claims 1-13 The data flow to the resource block mapping method.

26. A storage medium storing a computer readable program, wherein the computer readable program causes a computer to perform a data stream to a resource block according to any one of claims 1-13 in a multiple input multiple output system Mapping method.