CN101399589B - Multi-antenna pilot mapping method - Google Patents
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- CN101399589B CN101399589B CN 200710149999 CN200710149999A CN101399589B CN 101399589 B CN101399589 B CN 101399589B CN 200710149999 CN200710149999 CN 200710149999 CN 200710149999 A CN200710149999 A CN 200710149999A CN 101399589 B CN101399589 B CN 101399589B
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Abstract
The invention discloses a multi-antenna pilot frequency mapping method by aiming at a second frame structure of a long-term evolution system. A base station sends control information to a mobile terminal by precoding according to a request of the terminal; the mobile terminal computes a channel matrix according to a resource block in the control information, and feeds the obtained channel information to the base station; the base station determine a multi-antenna processing mode used by the data channel according to the channel information, and sends the control information of the multi-antenna processing mode to the mobile terminal; the base station sends information of the data channel by the multi-antenna processing mode, and inserts the pilot frequency with a pilot frequency structure corresponding to the multi-antenna processing mode; and the mobile terminal estimates the control channel and the data channel by the multi-antenna processing mode and the corresponding pilot frequency structure, and finishes decoding of the received data. The method supports space division multiplexing of multi-beams and improves a cell throughput; and the base station smartly selects an MIMO mode used by the mobile terminal according to the condition of the channel.
Description
Technical field
The present invention relates to Long Term Evolution (Long term evolution is called for short LTE) system, specifically, relate to a kind of multi-antenna pilot mapping method in the LTE system.
Background technology
Wave beam forms can increase the residential quarter covering, improves the link performance of Cell Edge User, but and the interference of implementation space elimination, increase power system capacity, be one of multiple-input and multiple-output (MIMO) mode main in the LTE wireless communication system.Fig. 1 shows the operation principle signal of LTE system transmitting terminal, user's information bit is through ovennodulation, the resource that modulation symbol and this UE (User Terminal) are assigned with should be set as the RB size of regulation, then after too much antenna processing, insert common pilot sequence according to the public guide frequency pattern, then after doing the OFDM conversion, launch from antenna for base station.After the UE termination is received signal, make the OFDM inverse transformation, then extract public guide frequency according to pilot frequency design, receive the detection of signal.
In the LTE system, public guide frequency inserts after multi-antenna technology is processed and transmits, and can only be used for the base station to the channel estimating of the omnidirectional channel of portable terminal, and can not estimate the directional channel after wave beam forms.Be unable to estimate the emission value that wave beam forms according to public guide frequency, so can not finish the decoding that wave beam forms rear portable terminal.
Therefore determined in frame structure 2, to define dedicated pilot in the LTE49# meeting, to support the application of beam-forming technology, inserted the Beam Forming System schematic diagram of dedicated pilot as shown in Figure 2.Formed following three kinds of comparatively main solutions in the LTE50# meeting:
Scheme 1: keep all public guide frequencies, increase dedicated pilot.The advantage of this scheme is the channel estimating quality that has guaranteed Common Control Channel, but newly-increased dedicated pilot causes expense too large.
Scheme 2: keep the pilot tone of two OFDMs (OFDM) symbol as public guide frequency, in order to the detection of Common Control Channel, other replace with dedicated pilot.The advantage of this scheme is that expense is little than scheme 1, and the channel estimating quality of data channel is better than scheme 1, but because the less quantity of public guide frequency, so reduced the channel estimating quality of Common Control Channel,
Scheme 3: all public guide frequencies are all replaced with dedicated pilot.Because Common Control Channel need to keep omnidirectional channel, be unsuitable for adopting wave beam to form, therefore this pilot frequency format covering and the data channel that how to solve Common Control Channel is consistent, and remains a key issue that needs to be resolved hurrily.
In scheme 1 and the scheme 2, for the RB that does not contain control information (Resource Block Resource Block), still insert some public guide frequencies, not only increased pilot-frequency expense, and to improving performance without any help, caused the waste of efficient resource.The main thought of scheme 1 and scheme 2 is still to be used precoding as a kind of main MIMO technology, but wave beam is formed on the throughput that improves edge customer, special advantage is arranged on the implementation space is multiplexing, especially under tdd mode, the condition ratio of channel reciprocity is easier to possess, the open loop wave beam forms can reduce feedback overhead greatly, guarantees good systematic function.Therefore wave beam forms and become the MIMO technology that has his own strong points with the precoding performance advantage in the second frame structure.By the compromise consideration to expense and performance, because the pilot configuration of scheme 1 and scheme 2 will increase pilot-frequency expense undoubtedly greatly, so compare with scheme 3, there is not the advantage on the performance.
On the other hand, stipulate in the agreement that front 0～3 OFDM symbol of each Resource Block is as control signal.In order to guarantee that omnidirectional covers, Common Control Channel can't be used public guide frequency, then adopt the covering of the data channel that wave beam forms greater than the covering of control channel, the covering of interior each symbol of RB is with difference, enlarge covering even adopt power to strengthen (power boosting), also will because of in a RB, repeatedly changing transmitting power, make the operation of system become very complicated, and because chugging causes the distortion of two ends symbol, also can greatly affect the performance of system.The covering that the mode that namely repeats with symbol improves control channel, the expense of control signal increases greatly on the one hand, also is difficult to the covering that guarantees that control channel is stable.
In view of reducing expense and the covering of being convenient to unified control channel and data channel, the present invention is based on such scheme 3 and improve.
Summary of the invention
Technical problem to be solved by this invention is to be to provide a kind of multi-antenna pilot mapping method, is intended to the MIMO mode that adopt according to the condition flexible choice portable terminal of channel the base station.
In order to solve the problems of the technologies described above, the invention provides a kind of multi-antenna pilot mapping method, for long evolving system the second frame structure, comprising:
(1) base station receives the initial access request of portable terminal, and the mode by precoding sends control information to described portable terminal;
(2) portable terminal calculates channel matrix according to the Resource Block in the described control information, with the feedback of channel information that obtains to described base station;
(3) described base station is according to described channel information, and many antenna processing mode that the decision data channel adopts send to described portable terminal with the control information of described many antenna processing mode;
(4) described base station adopts described many antenna processing mode to send the information of data channel, and employing and the corresponding pilot configuration insertion of described many antenna processing mode pilot tone;
(5) described portable terminal carries out the channel estimating of control channel and data channel according to described many antenna processing mode and corresponding pilot configuration, finishes the decoding to receive data.
Concrete pilot tone pattern such as Fig. 3,4, shown in 5,6, under many antenna processing mode MIMO of precoding pattern, pilot tone is inserted after many antenna processing, each road pilot tone is inserted at different antennas, solves the channel impulse response of each root antenna during reception according to pilot tone, and this pilot tone pattern has designed 4 tunnel pilot tones, process by the mapping greater than 4 antennas, can also support the situation greater than 4 antennas; Under many antenna processing mode MIMO mode that wave beam forms, pilot tone was inserted before many antenna processing, carrying out together wave beam with data message forms, on wave beam corresponding to each road pilot tone, if employing simple beam, then only insert one tunnel pilot tone, if adopt two wave beams, then insert the two-way pilot tone.This pilot tone pattern is supported at most three wave beams.
Further, channel information described in the described step (2) comprises the parameter of described channel matrix.
Further, the parameter of described channel matrix comprises the order of described channel matrix.
Further, many antenna processing mode described in the step (3) comprise that precoding and wave beam form.
Further, described many antenna processing mode are all adopted after judging many antenna processing mode of described data channel employing in base station described in the step (3) in this time scheduling of resource.
Further, control information comprises control bit described in the step (3).
Further, the common channel of described long evolving system and multi-medium broadcast/group broadcast single frequency network are professional, send in the Resource Block of precoding.
Further, described common channel comprises packet broadcast channel, Physical Control Format Indicator Channel and physics multileaving channel.
Further, the Resource Block of described precoding uses common pilot configuration, since 0 time slot continuous dispensing.
Further, greater than 4 situation, described precoding is to carry out first precoding according to 4 virtual-antennas first for antenna amount, then the result of 4 virtual-antenna precodings is mapped on 8 antennas or the more antennas.
Compared with prior art, the present invention has the following advantages:
(1) can support the space division multiplexing of multi-beam, greatly improve cell throughout;
(2) precoding under compatible various antenna mode and the scene and wave beam form;
(3) be convenient to the covering of unified control channel and data channel;
(4) different MIMO technology are reduced to minimum to the impact of portable terminal;
(5) support the self adaptation of multi-antenna technology to switch.
Description of drawings
Fig. 1 is the operation principle schematic diagram that LTE system transmitting terminal inserts public guide frequency;
Fig. 2 is the operation principle schematic diagram that LTE system wave beam forms transmitting terminal insertion dedicated pilot under the MIMO mode;
Fig. 3 is the mapping mode of wave beam pilot tone when being formed on short CP;
Fig. 4 is the mapping mode of wave beam pilot tone when being formed on long CP;
Fig. 5 is the mapping mode of precoding pilot tone when short CP;
Fig. 6 is the mapping mode of precoding pilot tone when long CP;
Fig. 7 is the inventive method embodiment step schematic diagram.
Embodiment
For making the purpose, technical solutions and advantages of the present invention clearer, below in conjunction with accompanying drawing the present invention is described in further detail.
Precoding and wave beam form two kinds of patterns as many antenna processing mode MIMO, and performance advantage has separately determined that the applicable situation of these two kinds of technology is different: precoding is fit to channel sequence greater than 1 situation, is suitable for multipath channel than more rich occasion; Wave beam forms and is fit to the situation that channel sequence equals 1, and the energy that is suitable for through (LOS) footpath or main footpath is obviously greater than the energy of other multipaths.But their application conditions is not completely divided, and according to the difference of channel condition, user A may be fit to adopt precoding under Same Scene, and user B then may be fit to adopt wave beam to form.Therefore design a kind of flexibly, have more compatible pilot configuration, more be conducive to the advantage of the many antennas of performance under various channel conditions, improve the availability of frequency spectrum of E-UTRA system.In sum, the present invention proposes a kind of pilot design method of compatible two kinds of MIMO technology.
Bare bones of the present invention mainly comprises:
(1) when each user resources scheduling, base station (Base Station, be called for short BS) judge the type of its multi-antenna technology, and the antenna technology type informed portable terminal (User Equipment, be called for short UE), then the RB that transmits and receives of this user adopts and the corresponding pilot configuration of its antenna technology type.
(2) common channel such as packet broadcast channel (PBCH), Physical Control Format Indicator Channel (Physical Control Format Indicator Channel, be called for short PCFICH) and physics multileaving channel (Physical Multicast Channel, be called for short PMCH), and multi-medium broadcast/group broadcast (MBMS) single frequency network (MBMS Single Frequency Network, abbreviation MBSFN) business sends in the RB of precoding, and UE carries out neighbor cell measurement by the RB of precoding.
(3) RB of precoding uses common pilot configuration, and in order to guarantee the interpolation effect of public guide frequency among the precoding RB, it is since 0 time slot continuous dispensing.The common pilot configuration of precoding is seen Fig. 3 and Fig. 4.
(4) RB of wave beam formation removes public guide frequency, and only uses dedicated pilot, and the mapping method of its pilot tone and Resource Block is seen Fig. 5 and shown in Figure 6.
(5) among the RB of precoding, 1,2,3,4 antennas such as Fig. 3 and Fig. 4 definition.In the situation greater than 4 antennas, carry out first precoding by 4 virtual-antennas, and then by other mapping mode, on the antenna of the signal map to 8 after the precoding of 4 virtual-antennas or other more antennas.Therefore for the configuration greater than 4 antennas, precoding is routinely 4 antenna situations of pattern processing still, like this can be so that the common pilot configuration of 4 antennas is still supported the precoding configuration greater than 4 antennas.
(6) among the RB that wave beam forms, the position of the pilot tone almost RB with precoding is identical, and the characteristic of just pilot tone being distinguished by antenna is replaced by the characteristic that pilot tone is distinguished by wave beam.Different UE uses different pilot demodulated to receive signal and realizes space division multiplexing (SDMA).
Based on the basic fundamental main points of the invention described above, Fig. 7 has provided the step of the embodiment of the invention, comprising:
The pilot configuration that the present invention is directed to LTE the second frame structure design a kind of compatible precoding and wave beam forms, this pilot configuration forms the essentially identical pilot tone pattern of employing for precoding and wave beam, but the pilot tone of precoding is distinguished according to antenna, and the pilot tone that wave beam forms is distinguished according to wave beam.
In when precoding, the weight coefficient that the base station wave beam forms is determined by UE, and the user is difficult to know the channel information of interference user, so can't effectively suppress interference by downlink at the base station end based on the method for precoding.If UE only has an antenna, realize that MU-MIMO will be very difficult; This also is why sometimes MU-MIMO compares the main cause that there is no too large advantage with SU-MIMO.Wave beam forms the weight coefficient that middle base station is decided downlink wave beam in its sole discretion, so have the not available interference rejection capability of precoding.Therefore, Beamforming Method is not only that than the advantage of method for precoding its weight coefficient quantization error is little, and is that it possesses the interference rejection capability that the latter does not possess, and can effectively support the MU-MIMO mode.
If pilot design is reasonable, adaptive beam can be supported plural wave beam, can realize SDMA and SU-MIMO, and for above-mentioned reasons, the performance of multi-beam space division multiplexing is better than method for precoding in the MU-MIMO situation.
The precoding of any antenna amount of pilot configuration support and antenna distance among the present invention greater than 4 precoding, is carried out precoding by 4 virtual-antennas for the antenna for base station number first, then it is mapped on 8 antennas.Therefore for the configuration greater than 8 antennas, precoding is routinely 4 antenna situations of pattern processing still, like this can be so that the common pilot configuration of 4 antennas is still supported the precoding configuration greater than 4 antennas.
Pilot configuration also supports the wave beam of any antenna amount and antenna distance to form among the present invention, supports that the maximum numbers of beams of space division multiplexing is 3.Do not form the Typical Disposition of using although large antenna distance is not wave beam, eliminate easily other users in the time of can being formed on spatial reuse by wave beam and disturb, and greatly improve the advantage of edge customer link-quality, greatly improve the throughput of residential quarter.
The pilot tone of the second frame structure down link and the mapping method of Physical Resource Block in the LTE system that the present invention proposes support wave beam to form and precoding is used in the LTE system flexible, compatiblely.Because control channel sends in different RB with the data channel that wave beam forms, can carry out increased power to whole RB, repeat to send or select lower order of modulation to enlarge the covering of control channel, the mode that in a RB, coexists with respect to public guide frequency and dedicated pilot, this pilot configuration is more convenient, carries out to better effects if the scheduling of power, coded system and modulation system.
Which kind of MIMO pattern no matter the present invention take, and only be that the complexity of base station has improved, but the method for operation of terminal is almost consistent, and the work of having saved codeword selection and feedback thereof, so only many options can increase the complexity of UE hardly.
Pilot configuration of the present invention is reduced to minimum to the complexity of UE, the MIMO mode that BS can adopt according to the condition flexible choice UE of channel, immediately inform the control bit of UE MIMO mode, then can in the RB of correspondence, adopt corresponding pilot frequency format emission or reception.
Claims (10)
1. a multi-antenna pilot mapping method for long evolving system the second frame structure, is characterized in that, comprising:
(1) base station receives the initial access request of portable terminal, and the mode by precoding sends control information to described portable terminal;
(2) portable terminal calculates channel matrix according to the Resource Block in the described control information, with the feedback of channel information that obtains to described base station;
(3) described base station is according to described channel information, and many antenna processing mode that the decision data channel adopts send to described portable terminal with the control information of described many antenna processing mode;
(4) described base station adopts described many antenna processing mode to send the information of data channel, and employing and the corresponding pilot configuration insertion of described many antenna processing mode pilot tone;
(5) described portable terminal carries out the channel estimating of control channel and data channel according to described many antenna processing mode and corresponding pilot configuration, finishes the decoding to receive data.
2. multi-antenna pilot mapping method as claimed in claim 1 is characterized in that, channel information comprises the parameter of described channel matrix described in the step (2).
3. multi-antenna pilot mapping method as claimed in claim 2 is characterized in that, the parameter of described channel matrix comprises the order of described channel matrix.
4. multi-antenna pilot mapping method as claimed in claim 1 is characterized in that, many antenna processing mode described in the step (3) comprise that precoding and wave beam form.
5. multi-antenna pilot mapping method as claimed in claim 1 is characterized in that, described many antenna processing mode are all adopted after judging many antenna processing mode of described data channel employing in base station described in the step (3) in this time scheduling of resource.
6. multi-antenna pilot mapping method as claimed in claim 1 is characterized in that, control information comprises control bit described in the step (3).
7. multi-antenna pilot mapping method as claimed in claim 1 is characterized in that, the common channel of described long evolving system and multi-medium broadcast/group broadcast single frequency network are professional, send in the Resource Block of precoding.
8. multi-antenna pilot mapping method as claimed in claim 7 is characterized in that, described common channel comprises packet broadcast channel, Physical Control Format Indicator Channel and physics multileaving channel.
9. multi-antenna pilot mapping method as claimed in claim 1 is characterized in that, the Resource Block of described precoding uses common pilot configuration, since 0 time slot continuous dispensing.
10. multi-antenna pilot mapping method as claimed in claim 1, it is characterized in that, greater than 4 situation, described precoding is to carry out first precoding according to 4 virtual-antennas first for antenna amount, and then the result with 4 virtual-antenna precodings is mapped on the many antennas.
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Families Citing this family (15)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN101932096B (en) * | 2009-06-24 | 2015-03-25 | 中兴通讯股份有限公司 | Method and system for notifying layer mapping information under multi-user multiple input multiple output mode |
| CN101998576B (en) * | 2009-08-13 | 2013-05-22 | 电信科学技术研究院 | Method and device for sending dedicated pilot using indication in advanced long-term evolution system |
| EP2485446A1 (en) * | 2009-09-29 | 2012-08-08 | Fujitsu Limited | Method and device for adding pilot |
| CN102036402B (en) * | 2009-09-30 | 2014-04-30 | 中兴通讯股份有限公司 | Layer mapping method and network equipment based on demodulating pilot frequency |
| CN101695009B (en) * | 2009-10-15 | 2014-12-10 | 中兴通讯股份有限公司 | System for sending descending control information format and method |
| US8804563B2 (en) | 2009-12-04 | 2014-08-12 | Telefonaktiebolaget L M Ericsson (Publ) | Apparatus and method for channel estimation in a wireless communications system |
| CN101867461B (en) * | 2010-04-30 | 2015-06-03 | 中兴通讯股份有限公司 | Channel information acquisition method and device and codebook construction method |
| CN102340371B (en) * | 2010-07-20 | 2014-10-22 | 大连海兰德维通信技术有限公司 | Transmission method and system of physical control format indicator channel |
| CN105680923A (en) | 2011-01-30 | 2016-06-15 | 北京新岸线移动多媒体技术有限公司 | MIMO data transmission realization method and device |
| CN103354478A (en) | 2011-03-31 | 2013-10-16 | 北京新岸线移动多媒体技术有限公司 | Method used for realizing link self adaption, network device and terminal device |
| US10383092B2 (en) * | 2015-11-03 | 2019-08-13 | Qualcomm Incorporated | Beamforming report structure |
| CN111030794A (en) * | 2015-12-03 | 2020-04-17 | 华为技术有限公司 | Data transmission method, base station and user equipment |
| CN106534030B (en) * | 2016-11-29 | 2019-05-31 | 重庆邮电大学 | A kind of channel estimation methods based on joint training sequence and pilot tone in 802.11n multiple antennas ofdm system |
| CN110166092B (en) * | 2018-02-14 | 2022-10-04 | 上海华为技术有限公司 | Method and device for generating mapping vector from data port to antenna |
| CN112929300B (en) * | 2019-12-05 | 2024-05-03 | 深圳市中兴微电子技术有限公司 | Data processing device, method, base station and storage medium |
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