CN103634069A - Downlink modulation encoding mode selection method - Google Patents
Downlink modulation encoding mode selection method Download PDFInfo
- Publication number
- CN103634069A CN103634069A CN201210300865.0A CN201210300865A CN103634069A CN 103634069 A CN103634069 A CN 103634069A CN 201210300865 A CN201210300865 A CN 201210300865A CN 103634069 A CN103634069 A CN 103634069A
- Authority
- CN
- China
- Prior art keywords
- mcs
- observation window
- error rate
- block error
- downlink
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
Images
Landscapes
- Detection And Prevention Of Errors In Transmission (AREA)
- Mobile Radio Communication Systems (AREA)
Abstract
The invention discloses a downlink modulation encoding mode selection method. The method comprises the following steps: a base station is used to perform statistics on the block error rate in an uplink modulation observation window and the block error rate in a downlink modulation observation window separately according to downlink ACK/NACK feedback; the block error rate in the downlink modulation observation window is greater than the maximum block error rate, then downlink modulation encoding mode MCS is modulated in a downlink manner; and the block error rate in the uplink modulation observation window is less than the minimum block error rate, then the MCS is modulated in a uplink manner. After applying embodiments of the invention, an uplink channel does not need to be occupied to feed back the downlink channel quality indication message, the uplink resource occupation can be reduced, so that the system uplink transmission capacity can be improved.
Description
Technical field
The application relates to communication technical field, more specifically, relates to the method for a kind of selection downlink modulation coding mode (MCS).
Background technology
In mobile communication system, the demand of high speed data transmission service constantly increases, and MCS, for transmitting downlink data faster and more accurately, need to be selected adaptively in base station, and this often need to, by means of uplink feedback passage, know the signal receiving quality of end side.In prior art, by terminal, down channel quality (CQI) is measured, and by certain ascending resource, CQI is reported to base station, then the MCS that downlink transfer is used is determined according to the CQI receiving in base station, and this is called CQI feedback mechanism.
Prior art can also be adjusted the carrier wave of terminal to report and interference-to-noise ratio by the descending error rate of statistics, using the MCS corresponding with interference-to-noise ratio of the carrier wave after adjustment as descending MCS.Or terminal estimates and receives the Signal to Interference plus Noise Ratio of signal and further determine CQI to be feedback, then descending MCS is determined according to the CQI of terminal feedback and decoded result in base station.Above-mentioned two kinds of methods need terminal to carry out the real-time report of CQI or carrier wave and interference-to-noise ratio, need to take a large amount of ascending resources, have reduced the resource of uplink traffic transmission.
More in short supply for ascending resource, and up-link capacity requires larger system, the ascending resource that this class feedback channel takies affects the volume of business of system largely.
Summary of the invention
The embodiment of the present invention proposes a kind of method of selecting downlink modulation coding mode, can reduce and take ascending resource, and then increase the uplink capacity of system
The technical scheme of the embodiment of the present invention is as follows:
Select a method for downlink modulation coding mode, described method comprises:
Base station is according to the ACK/NACK feedback of downlink transfer, and statistics raises the Block Error Rate in observation window and lowers the Block Error Rate in observation window respectively;
Block Error Rate in described downward observation window is greater than maximum Block Error Rate, lowers downlink modulation coding mode MCS;
Block Error Rate in described rise observation window is less than minimum Block Error Rate, raises MCS.
Set in advance the initial length of described rise observation window and the initial length of default described downward observation window.
After the N time MCS adjusting operation completes, if be operating as for the N time, lower MCS, be operating as for the N-1 time and raise MCS, and be operating as downward MCS for the N-2 time, adjust the length of described rise observation window for raising the twice of observation window initial length, N >=2.
Described base station comprises according to the Block Error Rate in the described rise observation window of ACK/NACK feedback statistics of downlink transfer:
Raise in the list of the inherent transmission of observation window outcome record and add up ACK number and NACK number, the Block Error Rate=NACK number in described rise observation window/(NACK number+ACK number).
Described base station comprises according to the Block Error Rate in the described downward observation window of ACK/NACK feedback statistics of downlink transfer:
Lower in the list of the inherent transmission of observation window outcome record and add up ACK number and NACK number, the Block Error Rate=NACK number in described downward observation window/(NACK number+ACK number).
Before described statistics, further comprise:
The length of pre-configured described transmission outcome record list, the length of described transmission outcome record list is more than or equal to the twice of maximum observation window initial length;
Maximum observation window is the maximum of described rise observation window initial length and described downward observation window initial length.
Described method further comprises:
Each radio frames of base station is received the list of the described transmission outcome record of feedback insertion, and deletes the data that exceed described transmission outcome record list length; Described feedback comprises ACK, NACK and NONE.
Described downward MCS comprises according to the downward step-length downward MCS setting in advance; Described rise MCS comprises according to the rise step-length rise MCS setting in advance.
Adjust after MCS for the M time, described method further comprises:
M >=2 o'clock, the adjustment type that records the M-1 time is to adjust type the M time, recording and adjusting type for the M-2 time is to adjust type the M-1 time; During M=1, recording the adjustment type of the M-1 time and the adjustment type of the M-2 time is to adjust type the M time.
Described method further comprises:
Base station is periodically according to the ACK/NACK of downlink transfer, and statistics raises the Block Error Rate and the Block Error Rate of lowering observation window in observation window respectively, and the minimum period is 1 radio frames.
After described definite downward MCS or rise MCS, further comprise: after meeting adjustment MCS condition, base station issues the order of lowering MCS or raising MCS.
From technique scheme, can find out, in embodiments of the present invention, base station is according to the ACK/NACK feedback of downlink transfer, and statistics raises the Block Error Rate and the Block Error Rate of lowering observation window in observation window respectively; Block Error Rate in described downward observation window is greater than maximum Block Error Rate, lowers MCS; Block Error Rate in described rise observation window is smaller than minimum Block Error Rate, raises MCS.The information self-adapting providing according to existing ACK/NACK feedback mechanism is adjusted MCS, does not need additionally to provide proprietary feedback channel, does not also additionally take uplink service resource, and then increases the uplink capacity of system.
Accompanying drawing explanation
Fig. 1 is for selecting the method flow schematic diagram of downlink modulation coding mode;
Fig. 2 is for selecting the embodiment of the method schematic flow sheet of descending adjustment coded system.
Embodiment
For making the object, technical solutions and advantages of the present invention express clearlyer, below in conjunction with drawings and the specific embodiments, the present invention is further described in more detail.
In example of the present invention, the ACK/NACK of base station Real-Time Monitoring downlink transfer feedback, is lowering observation window or is lowering the Block Error Rate of adding up a period of time in observation window, according to Block Error Rate, trigger descending MCS and select, if Block Error Rate is excessive, lower MCS, if Block Error Rate is too small, raise MCS.Further, in order to control flexibly the upper dynamics of lowering that is in harmonious proportion of MCS, statistics triggers the Block Error Rate of MCS rise operation and triggers MCS and lower the Block Error Rate operating respectively, makes the change of MCS both can follow the tracks of the variation of channel circumstance, guarantees that again Block Error Rate is in acceptable scope.
1 describe technical scheme of the present invention in detail by reference to the accompanying drawings, specifically comprise the following steps:
Base station is detected the ACK/NACK feedback of downlink transfer, respectively statistics of error rate in real time.Owing to being that the information self-adapting providing according to existing ACK/NACK feedback mechanism is adjusted MCS, do not need additionally to provide proprietary feedback channel, therefore additionally do not take uplink service resource.
The Block Error Rate of step 102, downward observation window is greater than maximum Block Error Rate, lowers downlink modulation coding mode MCS; The Block Error Rate raising in observation window is smaller than minimum Block Error Rate, raises MCS.
Along with Block Error Rate is adjusted MCS, and avoid the adjustment repeatedly of MCS, reduce further downlink transfer MCS and change the control channel expense of bringing.Particularly by adjustment, raise observation window and control the trigger rate that MCS rises, thereby guarantee that the Block Error Rate in whole transmitting procedure is lower.
Below in conjunction with specific embodiment, describe technical scheme of the present invention in detail.Accompanying drawing 2 is embodiment of the method schematic flow sheets of selecting descending adjustment coded system, specifically comprises the following steps:
Whether step 201, the upper radio frames of judgement receive ACK/NACK feedback, if receive, perform step 202; Otherwise perform step 204.
Whether the ACK/NACK feedback that step 202, judgement are received meets is recorded requirement, if meet record, require to perform step 203, otherwise, perform step 204.
The ACK/NACK receiving feeds back the MCS that corresponding MCS is up-to-date adjustment, determines that this feedback meets to record requirement; Otherwise, determine that this feedback does not meet to record requirement.
Outcome record list is transmitted for each user safeguards a user in base station, record this user's transmission result, this list length can be joined the length of pre-configured transmission outcome record list, and the length of transmission outcome record list is more than or equal to the twice of maximum observation window initial length; Maximum observation window is for raising observation window initial length and the maximum of lowering observation window initial length.
Wherein, the span that user is transmitted the transmission result in outcome record list is { ACK, NACK, NONE}, ACK represents the success of some data packet transmission, and NACK represents bust this, and NONE represents not receive for the feedback of some packets or the feedback of receiving and do not meet statistical requirements.The feedback that does not meet statistical requirements is: the MCS that feeds back corresponding transfer of data use is not up-to-date adjusted MCS.Like this transmission result is divided to three kinds of situation statistics, can improve Block Error Rate statistical accuracy, thereby make the judgement of rational adjustment MCS.
Receive that upgrading user after feedback result transmits outcome record list at every turn, the new transmission result of feedback is inserted to the gauge outfit of list.If the content of record exceeds configured list length, the data of table tail are deleted.
The transmission result statistics of error rate that transmits certain a period of time in outcome record list according to user, this time period is called observation window.In order to control flexibly MCS, raise, lower, arrange respectively and raise observation window, lower observation window, be designated as WINDOW_FOR_UP, WINDOW_FOR_DOWN.According to the initial length of the pre-configured rise observation window of prior art, and the initial length of lowering observation window.And the initial length of observation window is all less than or equal to the configured length that user is transmitted outcome record list.
Further have following scene: the amplitude of variation of supposing statistic SINR in a period of time is very little, select low order MCS, Block Error Rate is less, easily causes that MCS raises; Select high-order MCS, Block Error Rate increases, and the demodulation signal interference ratio that more high-order MCS requires is higher, and is more easily subject to the impact of signal interference ratio shake and makes Block Error Rate variation, easily causes that MCS lowers.So, MCS may be on best MCS and best MCS adjusts between the MCS of single order back and forth, has both brought higher re-authorization expense, is unfavorable for again reducing Block Error Rate.Therefore, raising observation window length needs adaptive change, makes MCS rise operation more careful, avoids MCS to fluctuate back and forth.
According to user, transmit the transmission result statistics of error rate in observation window in outcome record list.Statistics judgement MCS raises the rise Block Error Rate operating and is designated as BLER_FOR_UP respectively; Judgement MCS lowers the downward Block Error Rate of operation, is designated as BLER_FOR_DOWN.
The acceptable maximum Block Error Rate MAX_BLER of pre-configured transmission, value 10%; Pre-configured minimum Block Error Rate MIN_BLER, value 1%.In lowering observation window length, statistics is lowered Block Error Rate, and described downward Block Error Rate is greater than maximum Block Error Rate, lowers MCS; In raising observation window length, statistics raises Block Error Rate, and described rise Block Error Rate is less than minimum Block Error Rate, raises MCS.
When adjusting MCS, the gauge outfit of transmitting outcome record list from user, count that ACK in raising watch window counts ACK_NUM and NACK counts NACK_NUM and calculates the Block Error Rate raising in observation window:
BLER_FOR_UP=NACK_NUM/(ACK_NUM+NACK_NUM)；
When adjusting MCS, the gauge outfit of transmitting outcome record list from user, count that ACK in lowering watch window counts ACK_NUM and NACK counts NACK_NUM and calculates the Block Error Rate of lowering in observation window:
BLER_FOR_DOWN=NACK_NUM/(ACK_NUM+NACK_NUM)。
Adjusting Block Error Rate can be periodic statistics (cycle can join, and the minimum period is 1 radio frames).In judgement, adjust after MCS, base station does not issue the order of lowering MCS or raising MCS at once.But need to judge whether to meet MCS condition, meet MCS condition, issue the order of lowering MCS or raising MCS; On the contrary, do not meet MCS condition, do not issue the order of lowering MCS or raising MCS.MCS condition can be set according to specific circumstances, such as: MCS etc. is lowered in continuous three judgements.
If step 207 is lowered Block Error Rate and is greater than maximum Block Error Rate, lower MCS; Otherwise, perform step 209.
If step 208 raises Block Error Rate and is less than minimum Block Error Rate, raise MCS; Otherwise, perform step 209.
Watch window length is raised in step 209, renewal, upgrades and adjusts type.
WINDOW_FOR_DOWN, remains unchanged after configuration initial length; WINDOW_FOR_UP, configuration initial length, after MCS changes, judgement: lower operation if current wireless frame carries out MCS, last time is operating as MCS rise and the upper last time is operating as MCS downward, the length of WINDOW_FOR_UP increases the twice of initial length so, and in addition, WINDOW_FOR_UP is initial length.
MCS adjusting operation comprises mediation downward.The action type of record last time and upper last time, adjusts trend for following the tracks of MCS, changes in time the parameter that affects MCS adjusting operation.After MCS changes, the action type of record last time and upper last time.If MCS adjusts for the first time, last the and upper last time is all recorded as the type of current MCS adjusting operation; Otherwise, the last time is adjusted to type assignment to upper last action type, the last type of adjusting of record is that current MCS adjusts type.
The above, be only preferred embodiment of the present invention, is not intended to limit protection scope of the present invention.Within the spirit and principles in the present invention all, any modification of doing, be equal to replacement, improvement etc., within all should being included in protection scope of the present invention.
Claims (11)
1. a method of selecting downlink modulation coding mode, is characterized in that, described method comprises:
Base station is according to the ACK/NACK feedback of downlink transfer, and statistics raises the Block Error Rate in observation window and lowers the Block Error Rate in observation window respectively;
Block Error Rate in described downward observation window is greater than maximum Block Error Rate, lowers downlink modulation coding mode MCS;
Block Error Rate in described rise observation window is less than minimum Block Error Rate, raises MCS.
2. select according to claim 1 the method for downlink modulation coding mode, it is characterized in that, set in advance the initial length of described rise observation window and the initial length of default described downward observation window.
3. select according to claim 1 the method for downlink modulation coding mode, it is characterized in that, after the N time MCS adjusting operation completes, if be operating as for the N time, lower MCS, be operating as for the N-1 time and raise MCS, and be operating as for the N-2 time and lower MCS, adjust the length of described rise observation window for raising the twice of observation window initial length, N >=2.
4. select according to claim 1 the method for downlink modulation coding mode, it is characterized in that, described base station comprises according to the Block Error Rate in the described rise observation window of ACK/NACK feedback statistics of downlink transfer:
Raise in the list of the inherent transmission of observation window outcome record and add up ACK number and NACK number, the Block Error Rate=NACK number in described rise observation window/(NACK number+ACK number).
5. select according to claim 1 the method for downlink modulation coding mode, it is characterized in that, described base station comprises according to the Block Error Rate in the described downward observation window of ACK/NACK feedback statistics of downlink transfer:
Lower in the list of the inherent transmission of observation window outcome record and add up ACK number and NACK number, the Block Error Rate=NACK number in described downward observation window/(NACK number+ACK number).
6. according to the method for selecting downlink modulation coding mode described in claim 4 or 5, it is characterized in that, before described statistics, further comprise:
The length of pre-configured described transmission outcome record list, the length of described transmission outcome record list is more than or equal to the twice of maximum observation window initial length;
Maximum observation window is the maximum of described rise observation window initial length and described downward observation window initial length.
7. according to the method for selecting downlink modulation coding mode described in claim 4 or 5, it is characterized in that, described method further comprises:
Each radio frames of base station is received the list of the described transmission outcome record of feedback insertion, and deletes the data that exceed described transmission outcome record list length; Described feedback comprises ACK, NACK and NONE.
8. select according to claim 1 the method for downlink modulation coding mode, it is characterized in that, described downward MCS comprises according to the downward step-length downward MCS setting in advance; Described rise MCS comprises according to the rise step-length rise MCS setting in advance.
9. select according to claim 1 the method for downlink modulation coding mode, it is characterized in that, adjust after MCS for the M time, described method further comprises:
M >=2 o'clock, the adjustment type that records the M-1 time is to adjust type the M time, recording and adjusting type for the M-2 time is to adjust type the M-1 time; During M=1, recording the adjustment type of the M-1 time and the adjustment type of the M-2 time is to adjust type the M time.
10. select according to claim 1 the method for downlink modulation coding mode, it is characterized in that, described method further comprises:
Base station is periodically according to the ACK/NACK of downlink transfer, and statistics raises the Block Error Rate and the Block Error Rate of lowering observation window in observation window respectively, and the minimum period is 1 radio frames.
11. select the method for downlink modulation coding mode according to claim 1, it is characterized in that, after described definite downward MCS or rise MCS, further comprise: after meeting adjustment MCS condition, base station issues the order of lowering MCS or raising MCS.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201210300865.0A CN103634069A (en) | 2012-08-22 | 2012-08-22 | Downlink modulation encoding mode selection method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201210300865.0A CN103634069A (en) | 2012-08-22 | 2012-08-22 | Downlink modulation encoding mode selection method |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN103634069A true CN103634069A (en) | 2014-03-12 |
Family
ID=50214745
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201210300865.0A Pending CN103634069A (en) | 2012-08-22 | 2012-08-22 | Downlink modulation encoding mode selection method |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN103634069A (en) |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105024785A (en) * | 2014-04-30 | 2015-11-04 | 普天信息技术有限公司 | Method and system of determining downlink MCS |
| CN106712891A (en) * | 2015-07-17 | 2017-05-24 | 普天信息技术有限公司 | Modulation coding scheme level adjustment method and system |
| CN108768589A (en) * | 2018-05-22 | 2018-11-06 | 京信通信系统（中国）有限公司 | The adjusting method and device of initial MCS configurations |
| CN109687937A (en) * | 2017-10-19 | 2019-04-26 | 普天信息技术有限公司 | Modulation coding scheme and number of repetition selection method and device |
-
2012
- 2012-08-22 CN CN201210300865.0A patent/CN103634069A/en active Pending
Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105024785A (en) * | 2014-04-30 | 2015-11-04 | 普天信息技术有限公司 | Method and system of determining downlink MCS |
| CN105024785B (en) * | 2014-04-30 | 2019-02-26 | 普天信息技术有限公司 | Determine the method and system of downlink MCS |
| CN106712891A (en) * | 2015-07-17 | 2017-05-24 | 普天信息技术有限公司 | Modulation coding scheme level adjustment method and system |
| CN106712891B (en) * | 2015-07-17 | 2019-07-23 | 普天信息技术有限公司 | Modulation and Coding Scheme level adjustment method and system |
| CN109687937A (en) * | 2017-10-19 | 2019-04-26 | 普天信息技术有限公司 | Modulation coding scheme and number of repetition selection method and device |
| CN109687937B (en) * | 2017-10-19 | 2021-08-06 | 普天信息技术有限公司 | Modulation coding mode and repetition frequency selection method and device |
| CN108768589A (en) * | 2018-05-22 | 2018-11-06 | 京信通信系统（中国）有限公司 | The adjusting method and device of initial MCS configurations |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN102271389B (en) | Uplink power control method and system | |
| EP2816840B1 (en) | Adaptive transmission scheme with two modes of operation | |
| CN101213769B (en) | Method and apparatus for adjusting channel quality indicator feedback period to increase uplink capacity | |
| KR101024052B1 (en) | Method and system for constructing channel quality indicator tables for feedback in a communication system | |
| CN103081528B (en) | For reporting the method and apparatus of maximum transmit power in wireless communications | |
| CN101420744B (en) | Radio communication system, radio communication method, base station and radio terminal | |
| CN102378255B (en) | Method and device for improving transmission performance of physical downlink control channel (PDCCH) | |
| US7894822B2 (en) | Apparatus and method in a cellular network | |
| CA2649408A1 (en) | Method for radio resource control requested codec rate control for voip | |
| CN101133587A (en) | HSDPA parameters adjustment based on CQI age | |
| CN102790654A (en) | Method for determining downlink transmission MCS (Modulating and Coding Scheme) | |
| CN102970717B (en) | Method and device for switching different downlink transmission modes of LTE (long term evolution) system | |
| DE102012014650A1 (en) | Flow Control | |
| CN101621829B (en) | Method and device for reporting channel quality indicator | |
| EP2887572B1 (en) | Open-loop link adaption adjusting method and device | |
| CN101674654A (en) | PDCCH channel encoding rate regulation method and evolution base station | |
| CN103634069A (en) | Downlink modulation encoding mode selection method | |
| CN104348574A (en) | Method and device for adjusting modulation and coding scheme | |
| CN101466123A (en) | Selection method, device and system of ascending enhancement transformat set in mobile communication | |
| CN102611521B (en) | Adjusting method for channel quality indicator (CQI) | |
| EP2770658A1 (en) | Method and system for sending control signaling | |
| CN102377513A (en) | Adaptive modulation and coding method and device | |
| CN101651516B (en) | Method and system for encoding modulation | |
| CN105024785B (en) | Determine the method and system of downlink MCS | |
| US20140094204A1 (en) | Uplink Power Control for Machine Type Communication Devices |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| RJ01 | Rejection of invention patent application after publication |
Application publication date: 20140312 |
|
| RJ01 | Rejection of invention patent application after publication |