CN101159475B - Cell coordination method for suppressing terminal transmitted signal interference in OFDM system - Google Patents
Cell coordination method for suppressing terminal transmitted signal interference in OFDM system Download PDFInfo
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Abstract
The invention discloses a cell coordinating method of suppressing the interference of a terminal-emitted signal in a orthogonal frequency division multiplexing access system, which includes the steps as following: according to the overlapped coverage relation between the cells that need to coordinate interference and the carrier mapping mode that can be used by a terminal, a media access control layer determines the logical sub channel distributed to the terminal in each cell that needs to coordinate interference; according to the feedback information of the terminal accessing to a cell base station, the cell base station determines whether the terminal is in the overlapped coverage region between the cells that need to coordinate interference; and if the terminal is in the overlapped coverage region, the cell base station informs the terminal of using the carrier mapping mode which the terminal can use, and transmits signals in the logical sub channel determined by the media access control layer.
Description
Technical field
The present invention relates to the communications field, relate more specifically to the cell coordination method that a kind of inhibition terminal that is used for OFDM access system transmits and disturbs.
Background technology
The uplink frame signal that send at overlapping covered terminal between the sub-district can receive concerning each sub-district.When these terminals employings were sent with frequency band signals, for the base station, the signal that is not linked into the terminal transmission of this base station was a kind of interference.As shown in Figure 1, three base station cells that drawn among the figure are respectively A cell base station, B cell base station and C cell base station.Wherein, terminal MS 1 is linked into the A cell base station, and terminal MS 2 is linked into the B cell base station.For the A cell base station, the signal that terminal MS 2 is sent is a kind of interference signal so.
The method of existing head it off is partial frequency multiplexing (FractionalFrequency Reuse is called for short a FFR) method, promptly to the different frequency range of the terminal distribution of different districts.As shown in Figure 2; A cell base station, B cell base station and C cell base station in Non-overlapping Domain in order to utilize bandwidth to greatest extent; Allow the terminal to send the up link frame signal of full frequency band F1+F2+F3; Because it is different that each sub-district Non-overlapping Domain receives signal strength signal intensity, even, also can not produce interference with frequently.For the overlapping region, the A cell base station is given the terminal distribution band segment F1 that is linked into the overlapping region, and the B cell base station is given the terminal distribution band segment F2 that is linked into the overlapping region, and the C cell base station is given the terminal distribution band segment F3 that is linked into the overlapping region.Like this; Because the sub-frame of uplink that send at the terminal of A, B, overlapping region, C sub-district can not take same frequency range; So the A cell base station can not go demodulation to be in the signal at the terminal, overlapping region of frequency range F2 or F3, the terminal is sent between the uplink frame and can not produced interference like this.
But the prerequisite of this solution is the transmission of terminal support sector frequency-division section, and promptly the terminal is supported in and carries out the subcarrier mapping mapping mode of (partial usage of subchannels is called for short PUSC) in the parton channel.In present communication field; The OFDM of a lot of producers inserts (Orthogonal Frequency Division Multiple Access; Be called for short OFDMA) the up transmit frame of system terminal not support sector divide the mapping of the carrier wave in the subchannel, and can only support the carrier wave whole subchannels in to shine upon.When these terminals were in the overlapping region, the base station just can't adopt FFR to coordinate to eliminate the interference between the different terminals transmit frame.Like this, under fixing frequency range, for the terminal of only supporting whole subchannel intercarrier mappings, the uplink signal interference that how to suppress between the sub-district is exactly a problem.
Summary of the invention
One or more problems in view of the above the invention provides the cell coordination method that a kind of inhibition terminal that is used for OFDM access system transmits and disturbs.
The cell coordination method that transmits and disturb according to the inhibition terminal that is used for OFDM access system of the embodiment of the invention; May further comprise the steps: media access control layer is the overlapping covering relation between the sub-district of coordinates interference and the terminal carrier wave mapping mode that can use as required, confirms to distribute to the logical sub-channel at the terminal in the sub-district that respectively needs coordinates interference; Cell base station is according to the feedback information at the terminal of inserting it, confirms whether the terminal is in overlapping covered between the sub-district that needs coordinates interference; And if the terminal be in overlapping covered in, then its carrier wave mapping mode that can use is used at cell base station notice terminal, on the logical sub-channel that media access control layer is confirmed, sends signal.
Wherein, need definite process of the sub-district of coordinates interference may further comprise the steps: cell base station is measured the overlay area of himself, and gives media access control layer with reporting measuring result; Media access control layer is confirmed the overlapping covering relation between each sub-district according to the measurement result that cell base station reports, and confirms the sub-district of needs coordinates interference according to the overlapping covering relation between each sub-district.
Wherein, cell base station uses the carrier wave mapping mode in whole subchannels to send signal through the terminal that uplink map (UpLink Map, be called for short ULMAP) message informing is in overlapping covered.Cell base station is in use at overlapping covered interior terminal needs the sub-district of coordinates interference with other logical sub-channel different logical subchannel transmission signal through the ULMAP message informing.Cell base station is in overlapping covered interior terminal use through uplink path description (Uplink ChannelDescriptor is called for short UCD) message informing needs the identical carrier wave mapping parameters of carrier wave mapping parameters of the sub-district of coordinates interference to send signal with other.
Wherein, In the OFDMA system; The carrier wave mapping mode mainly contains following several kinds: use parton channel (partial usage of subchannels is called for short PUSC), optional PUSC arrangement mode (optional permutations of PUSC is called for short OptionalPUSC), use whole subchannels (full usage of subchannels; Be called for short FUSC) and self adaptation arrangement mode (adaptive modulation and coding is called for short AMC).Wherein, PUSC belongs to part subchannel carrier mapping mode, and Optional PUSC and FUSC belong to whole subchannel intercarrier mapping modes.
The present invention is different with the FFR method of partial frequency multiplexing, and the FFR method of partial frequency multiplexing requires the terminal must support sector to divide the subchannel intercarrier to shine upon and sends the uplink frame signal.And whole subchannel intercarrier mappings are only supported at the terminal that the present invention is suitable for, and do not support the PUSC parton channel intercarrier mapping of branch sector.The difference of the intercarrier mapping of PUSC parton channel and all subchannel intercarriers mappings can be referring to the 802.16e consensus standard not within declared range of the present invention when dividing the sector.
Description of drawings
Accompanying drawing described herein is used to provide further understanding of the present invention, constitutes the application's a part, and illustrative examples of the present invention and explanation thereof are used to explain the present invention, do not constitute improper qualification of the present invention.In the accompanying drawings:
Fig. 1 is the interference sketch map between the terminal uplink signal in overlapping covered;
Fig. 2 is to use the FFR method to coordinate the sketch map of the method for area interference;
Fig. 3 is the transmit flow chart of the cell coordination method that disturbs of the inhibition terminal that is used for OFDM access system according to the embodiment of the invention;
Fig. 4 is the sketch map of the situation of the coordination sub-frame of uplink allocated bandwidth of informing that in overlapping covered the terminal is adopted;
Fig. 5 is that sub-district A has adopted according to the uplink allocated bandwidth sketch map after the method for the embodiment of the invention;
Fig. 6 is that sub-district B has adopted according to the uplink allocated bandwidth sketch map after the method for the embodiment of the invention; And
Fig. 7 is that sub-district C has adopted according to the uplink allocated bandwidth sketch map after the embodiment of the invention method.
Embodiment
With reference to accompanying drawing, specify embodiment of the present invention below.
With reference to figure 3, the cell coordination method that the inhibition terminal that is used for OFDM access system according to the embodiment of the invention transmits and disturbs is described.As shown in Figure 3, this method may further comprise the steps:
S302, each cell base station is measured the overlay area of this base station, confirms non-overlapped overlay area and overlapping covered, and report measurement information is given media access control layer (MediaAccess Control is called for short MAC).Mac layer need be confirmed the overlapping covering relation between each sub-district, thereby need to confirm the base station of coordinates interference.For example, under the networking mode as shown in Figure 1, the base station that needs coordinates interference is A cell base station, B cell base station and C cell base station (the present invention is not limited to three cell base stations).Have three cell base stations and need coordinates interference.Then, mac layer confirms to distribute to the logical sub-channel at the terminal in the sub-district that respectively needs coordinates interference.In coordinating sub-frame of uplink, whole subchannels are divided into three parts.For the communication system of a 10M bandwidth, sub-frame of uplink has 35 logical sub-channel.The logical sub-channel of wherein, distributing for the A cell base station is 0～9.The logical sub-channel of distributing for the B cell base station is 10～19.The logical sub-channel of distributing for the C cell base station is 20～34 (sub-district is overlapping covered informs that the situation of the coordination sub-frame of uplink allocated bandwidth that adopts of accessing terminal is as shown in Figure 4).
S304, cell base station confirms that according to the feedback information that accesses terminal that is linked into it each position that accesses terminal is in non-overlapped overlay area or is in overlapping covered.
S306; Cell base station is in overlapping covered interior accessing terminal through the ULMAP message informing and uses the carrier wave mapping mode in whole subchannels to send signal, is in overlapping covered interior accessing terminal used needs the sub-district of coordinates interference with other logical sub-channel different logical subchannel transmission signal through the ULMAP message informing.Be in overlapping covered interior accessing terminal used needs the sub-district of coordinates interference with other the identical carrier wave mapping parameters transmission signal of carrier wave mapping parameters through the UCD message informing.
In order to satisfy the requirement of agreement to sub-frame of uplink, the bandwidth of the logical sub-channel that this sub-district is assigned to must be filled up, and does not promptly have remaining bandwidth.For example, the overlapping region has only a terminal use MS1 in the A cell base station, and the logical sub-channel of distributing to the A cell base station is 0～9 subchannel.If sub-frame of uplink has taken 15 symbols (supposing does not have control channel), the MS1 available bandwidth is 10*15/3=50 time slot (slot) bandwidth so.If this moment, the transmission data of terminal MS 1 only took 40 slot bandwidth, terminal MS 1 must be added the bandwidth that padding (filling) adapts to 50 slot of distribution in remaining bandwidth so.Suppose that the overlapping region also has only a terminal use MS2 in the B cell base station, the logical sub-channel of distributing to the B sub-district is 10～19 subchannels.At this moment, terminal MS 2 just can be discharged the data of oneself since the 10th subchannel.Because preceding 10 subchannel have been got well by the MS1 complete filling.Such fill rule mainly is must be according to beginning from first subchannel in order to satisfy protocol requirement different terminals user data; The emissions data and then from first symbol to a last symbol, and then discharge the regulation (distribution condition of the uplink of A, B, C sub-district such as Fig. 5 are to shown in Figure 7) of second subchannel.
Specify as follows, in the OFDMA system, in the uplink frame, and then data burst must discharge according to symbol sequence in a subchannel, and can not have vacant.When the method used according to the embodiment of the invention; Certain accesses terminal and has been assigned with the N subchannel; But the data that this request of accessing terminal is sent are fewer, fill out the bandwidth of discontented this N subchannel, and this moment is in order to satisfy protocol requirement; Cell base station can be distributed to the unnecessary bandwidth that accesses terminal to adapt to the total bandwidth of N subchannel in ULMAP, access terminal like this and must the bandwidth of all distribution have been filled according to agreement.Have only last data that access terminal not need such processing, because do not had terminal data thereafter.
In order to guarantee to coordinate the identical carrier wave mapping ruler of the whole employings of frame signal that accessing terminal in the sub-district sent, the MAC layer can mark off terminal use's data of overlapping region a zone in addition.For example, as shown in Figure 5, the uplink frame allocated bandwidth among the zone-1 is given accessing terminal of Non-overlapping Domain, and the uplink frame allocated bandwidth among the zone-2 is given accessing terminal of overlapping region.At this moment, all relevant parameters of queueing discipline of coordinating to adopt among the zone-2 of sub-district all must be identical.This parameter information is told to each by the unification of MAC layer and is coordinated cell base station.In second zone, promptly among the zone-2, the distribution of the uplink frame of A cell base station takies 0～9 logical sub-channel.The uplink frame of B cell base station is distributed in zone-2 and is taken 10～19 logical sub-channel.The uplink frame of C cell base station takies 20～34 logical sub-channel.
Wherein, need the transmit frame signals that accesses terminal in the sub-district of coordinates interference must all adopt identical carrier wave mapping rulers, promptly physical carrier all is identical with mapping relations between the logic carrier wave in each overlapping region, sub-district.Respectively need accessing terminal in the sub-district of coordinates interference must adopt the different logical subchannel.Wherein, logical sub-channel is a set of logic carrier wave.Like this, because the different logical carrier wave is adopted in accessing terminal of different districts, again because physical carrier all adopts identical mapping relations with the mapping relations of logic carrier wave, so accessing terminal of different districts also just used different physical carrier.Adopt between the data sending of access terminal of different physical carrier and can not produce interference.
The above is merely embodiments of the invention, is not limited to the present invention, and for a person skilled in the art, the present invention can have various changes and variation.All within spirit of the present invention and principle, any modification of being done, be equal to replacement, improvement etc., all should be included within the claim scope of the present invention.
Claims (7)
1. the cell coordination method that the inhibition terminal that is used for OFDM access system transmits and disturbs is characterized in that, may further comprise the steps:
Media access control layer is the overlapping covering relation between the sub-district of coordinates interference and the terminal carrier wave mapping mode that can use as required, confirms to distribute to the logical sub-channel at the terminal in each said sub-district that needs coordinates interference;
Cell base station is according to the feedback information at the terminal of inserting it, confirms whether said terminal is in overlapping covered between the said sub-district that needs coordinates interference; And
If said terminal be in said overlapping covered in, then said cell base station notifies said terminal to use its carrier wave mapping mode that can use, and on the said logical sub-channel that said media access control layer is confirmed, sends signal.
2. method according to claim 1 is characterized in that, the said definite process of the sub-district of coordinates interference that needs may further comprise the steps:
Said cell base station is measured the overlay area of himself, and gives said media access control layer with reporting measuring result;
Said media access control layer is confirmed the overlapping covering relation between each sub-district according to the measurement result that said cell base station reports, and confirms the sub-district of said needs coordinates interference according to the overlapping covering relation between said each sub-district.
3. method according to claim 2 is characterized in that, said cell base station is in said overlapping covered interior said terminal through the uplink map message informing and uses the carrier wave mapping mode in whole subchannels to send signal.
4. method according to claim 3; It is characterized in that said cell base station is in said overlapping covered interior said terminal through said uplink map message informing to be used and other said logical sub-channel different logical subchannels transmission signals that need the sub-district of coordinates interference.
5. method according to claim 4; It is characterized in that said cell base station is in said overlapping covered interior said terminal use through uplink path describing message notice and other said identical carrier wave mapping parameters of carrier wave mapping parameters of the sub-district of coordinates interference that need send signals.
6. method according to claim 5; It is characterized in that; Said cell base station is in said overlapping covered interior said terminal through said uplink map message informing must fill up the bandwidth that said logical sub-channel is occupied with the bandwidth of sending data; Wherein, the said logical sub-channel bandwidth of occupying is meant assignable data bandwidth on all the symbol time slots in the said logical sub-channel scope.
7. according to each described method in the claim 1 to 5, it is characterized in that,, then need not coordinate control said cell base station if said terminal is in the non-overlapped overlay area between the said sub-district that needs coordinates interference.
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| Application Number | Priority Date | Filing Date | Title |
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| CN2007101672631A CN101159475B (en) | 2007-11-02 | 2007-11-02 | Cell coordination method for suppressing terminal transmitted signal interference in OFDM system |
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| CN2007101672631A CN101159475B (en) | 2007-11-02 | 2007-11-02 | Cell coordination method for suppressing terminal transmitted signal interference in OFDM system |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| US8670432B2 (en) * | 2009-06-22 | 2014-03-11 | Qualcomm Incorporated | Methods and apparatus for coordination of sending reference signals from multiple cells |
| CN102013903B (en) * | 2009-09-29 | 2013-11-06 | 电信科学技术研究院 | Method and equipment for space coordination among cells |
| CN105210315B (en) * | 2013-05-07 | 2017-12-19 | Lg电子株式会社 | The method and its equipment of measurement are performed in a wireless communication system |
| CN104869094B (en) * | 2015-04-29 | 2018-04-20 | 清华大学 | The uplink multi-address cut-in method of united orthogonal multiple access and non-orthogonal multiple |
| CN107733591A (en) * | 2016-08-10 | 2018-02-23 | 北京信威通信技术股份有限公司 | Transmission method and device |
| US11411635B2 (en) * | 2018-03-19 | 2022-08-09 | Mediatek Singapore Pte. Ltd. | Spatial reuse in WLAN multi-AP network |
| CN112118580A (en) * | 2019-06-19 | 2020-12-22 | 华为技术有限公司 | Spectrum resource allocation method and device |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1251699A (en) * | 1997-03-31 | 2000-04-26 | 摩托罗拉公司 | Method and apparatus in radio communication system for implementing frequency reuse plan |
| WO2006086788A1 (en) * | 2005-02-11 | 2006-08-17 | Qualcomm Incorporated | Method and apparatus for mitigating interference in a wireless communication system |
| CN101031127A (en) * | 2007-02-01 | 2007-09-05 | 上海交通大学 | Method for decreasing same channel interference between users of upper FDMA cellular system |
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Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1251699A (en) * | 1997-03-31 | 2000-04-26 | 摩托罗拉公司 | Method and apparatus in radio communication system for implementing frequency reuse plan |
| WO2006086788A1 (en) * | 2005-02-11 | 2006-08-17 | Qualcomm Incorporated | Method and apparatus for mitigating interference in a wireless communication system |
| CN101031127A (en) * | 2007-02-01 | 2007-09-05 | 上海交通大学 | Method for decreasing same channel interference between users of upper FDMA cellular system |
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