CN103379616B

CN103379616B - A kind of time advance method of adjustment for LTE and device

Info

Publication number: CN103379616B
Application number: CN201210120087.7A
Authority: CN
Inventors: 余秋星; 刘丛
Original assignee: ZTE Corp
Current assignee: ZTE Corp
Priority date: 2012-04-23
Filing date: 2012-04-23
Publication date: 2016-09-07
Anticipated expiration: 2032-04-23
Also published as: CN103379616A

Abstract

The present invention provides a kind of time advance method of adjustment for Long Term Evolution LTE and device, and wherein, the method comprises the following steps: that Timing Advance TA measured value is smoothed by A, scheduler, and adds up in scheduled time window length effectively TA population of measured values；B, carry out time advance adjustment according to TA smooth value；C, effective TA population of measured values is compared with predetermined number threshold value, if less than predetermined number threshold value, then perform step D；Otherwise, terminate；D, scheduler are leading to LTE high level application-specific, and wherein, Special leader refers to the predefined targeting sequencing for non-competing Stochastic accessing.The present invention can be greatly improved the precision that time advance adjusts.

Description

A kind of time advance method of adjustment for LTE and device

Technical field

The present invention relates to wireless communication technology, particularly to a kind of time advance method of adjustment for LTE And device.

Background technology

In Long Term Evolution (Long Term Evolution, LTE) system, Timing Advance (Time Advance, TA) it is one and receives subscriber equipment (User for characterizing evolution base station (evolved NodeB, eNodeB) Equipment, UE) parameter of timing offset of sent data.In order to keep uplink synchronous, base station refers to Show UE regulation time point send uplink demodulation reference signal (Demodulation reference signal, DMRS) or detection reference signal (sounding reference signal, SRS), obtain through Timing measurement By Physical Downlink Shared Channel, time advance adjusts order to TA, eNodeB to be handed down to UE and adjust Whole, to keep the uplink synchronous of UE Yu eNodeB.

In LTE, it is relative to current up timing that time advance adjusts order, with 16 times of Ts (1Ts The basic time unit of LTE) multiple represent, and by the time adjust MAC Control Element Issue.Time adjusts the time advance adjustment order TA carrying 6 bits in MAC Control Element, uses Indicate relative to current definitely adjustment amount N_{TA, old}Relative adjustment amount, span is T_A=0,1 ..., 63, The newest absolute adjustment amount is expressed as N_{TA, new}=NTA, old+ (T_A-31) × 16, unit is Ts.

In prior art, usually base station is according to the instantaneous TA value measured, or puts down based on instantaneous value The sliding smooth value that obtains, then notice UE carries out the adjustment of TA.But, under low signal-to-noise ratio, owing to surveying The instantaneous value of amount is easily affected by noise and interference and is become inaccurate.If it addition, the TA that can obtain Measured value is less, considers further that UE mobility can make actual TA value have time varying characteristic, based on existing Technology carries out the adjustment of time advance, base station can be made not reach when adjusting the up delivery time of UE intended As a result, even disturb (ISI) between created symbol, thus greatly deteriorate the performance of uplink demodulation so that be System throughput degradation.

Summary of the invention

In order to solve the problems referred to above, the present invention provides a kind of time advance method of adjustment for LTE and dress Put, it is possible to increase the precision of time advance adjustment and efficiency.

The time advance method of adjustment for Long Term Evolution LTE of the present invention, comprises the following steps:

Timing Advance TA measured value is smoothed by A, scheduler, and it is long to add up scheduled time window Interior effectively TA population of measured values；

B, carry out time advance adjustment according to TA smooth value；

C, effective TA population of measured values is compared with predetermined number threshold value, if less than pre- Fixed number threshold value, then perform step D；Otherwise, terminate；

D, scheduler are leading to LTE high level application-specific, and wherein, Special leader refers to predefined use Targeting sequencing in non-competing Stochastic accessing.

Wherein, in described step A, effective TA measured value refers to, it is thus achieved that corresponding during TA measured value Signal to Interference plus Noise Ratio is higher than predetermined Signal to Interference plus Noise Ratio thresholding.

Wherein, in described step B, carry out time advance adjustment according to TA smooth value, put down including TA Issue TA to UE when sliding value meets regularization condition and adjust order, and exceed predetermined at TA timer Issuing to UE when time gate limit value and TA smooth value are unsatisfactory for regularization condition maintains synchronize not adjust TA Command process.

Wherein, described TA smooth value meets regularization condition and refers to based on TA smooth value once or continuous several times More than the condition of TA expectation adjusting range, wherein, TA expectation adjusting range referred to through the scheduled time The interval of convergence of TA value after time advance adjustment.

Wherein, to be that TA timer period deducts a fixing non-negative time inclined for described predetermined time gate limit value Shifting amount.

It addition, after described step D, may further include: judge whether that Special leader is arrived in application, If it is, perform step E；Otherwise, step G is performed；

E, issuing Special leader to UE, notice UE initiates Stochastic accessing；

F, after receiving the accidental access signal of UE, issue accidental access response, then terminate；

G, judge whether TA timer exceedes scheduled time thresholding, if it does, then issue unregulated TA order, is then back to step A；If be less than, the most directly return step A.

The time advance adjusting apparatus for Long Term Evolution LTE of the present invention, including scheduler and request slip Unit, wherein, described scheduler, for Timing Advance TA measured value is smoothed, and add up Effective TA population of measured values in scheduled time window length；And for according to the notice of described application unit to LTE high level application-specific is leading；Described application unit, for carrying out time advance tune according to TA smooth value Whole；Effective TA population of measured values is compared with predetermined number threshold value, if less than predetermined Number threshold value, then notify that described scheduler is leading to LTE high level application-specific, wherein, and Special leader Refer to the predefined targeting sequencing for non-competing Stochastic accessing.

Wherein, described effective TA measured value refers to, it is thus achieved that Signal to Interference plus Noise Ratio corresponding during TA measured value is higher than Predetermined Signal to Interference plus Noise Ratio thresholding；Described carry out time advance adjustment according to TA smooth value, including TA smooth value Issue TA to UE when meeting regularization condition and adjust order, and exceed the predetermined time at TA timer Issuing to UE when threshold value and TA smooth value are unsatisfactory for regularization condition maintains synchronize not adjust TA order Processing, wherein, described predetermined time gate limit value is that TA timer period deducts a fixing non-negative time Side-play amount.

Furthermore it is also possible to farther include judging unit, it is used for judging whether application unit applies for before special Lead, if application to; issue Special leader to UE, notice UE initiation Stochastic accessing, and receiving After the accidental access signal of UE, issue accidental access response；If not applying for arriving, then judge TA timing Whether device exceedes scheduled time thresholding, if it does, then issue unregulated TA order, then notifies to adjust Timing Advance TA measured value is smoothed by degree device, and adds up effectively TA in scheduled time window length Population of measured values；If be less than, the most directly Timing Advance TA measured value is put down by notice scheduler Sliding process, and add up in scheduled time window length effectively TA population of measured values.

The invention has the beneficial effects as follows: according to the time advance method of adjustment for LTE and the dress of the present invention Put, according to sharpening result and effective TA population of measured values statistics of TA measured value, less effectively in acquisition By triggering non-competing random access procedure during TA measured value, when obtaining more effective TA measured value Carry out time advance adjustment by TA smooth value, substantially increase the precision that time advance adjusts, it is to avoid When effectively TA measured value is less, TA smooth value cannot reflect that actual TA value changes, and smooths based on this Value carries out time advance and adjusts inaccurate, the problem even introducing ISI, it is achieved maintenance rapidly and efficiently is up Synchronize, thus finally improve throughput of system.

Accompanying drawing explanation

Fig. 1 is the basic procedure schematic diagram of the time advance method of adjustment of the embodiment of the present invention.

Detailed description of the invention

Hereinafter, the time advance method of adjustment for LTE and the dress of the present invention is described in detail with reference to accompanying drawing 1 Put.

100, Timing Advance TA measured value is smoothed by scheduler, and adds up scheduled time window Effective TA population of measured values in long；

200, time advance adjustment is carried out according to TA smooth value；

300, effective TA population of measured values is compared with predetermined number threshold value, if be less than Predetermined number threshold value, then perform step 400；Otherwise, terminate；

400, scheduler is leading to LTE high level application-specific, and wherein, Special leader refers to predefined Targeting sequencing for non-competing Stochastic accessing.

Wherein, in described step 100, effective TA measured value refers to, it is thus achieved that corresponding during TA measured value Signal to Interference plus Noise Ratio higher than predetermined Signal to Interference plus Noise Ratio thresholding.

Wherein, in described step 200, carry out time advance adjustment according to TA smooth value, including TA Issue TA to UE when smooth value meets regularization condition and adjust order, and exceed predetermined at TA timer Time gate limit value and TA smooth value issue to UE when being unsatisfactory for regularization condition and maintain synchronize not adjust TA Command process.

It addition, after described step 400, may further include: judge whether that Special leader is arrived in application, If it is, perform step 500；Otherwise, step 700 is performed；

500, issuing Special leader to UE, notice UE initiates Stochastic accessing；

600, after receiving the accidental access signal of UE, issue accidental access response, then terminate；

700, judge whether TA timer exceedes scheduled time thresholding, do not adjust if it does, then issue TA order, be then back to step 100；If be less than, the most directly return step 100.

The time advance adjusting apparatus for Long Term Evolution LTE of the present invention, including scheduler and request slip Unit, wherein, scheduler, for Timing Advance TA measured value is smoothed, and add up predetermined Effective TA population of measured values in time window；And it is high to LTE for the notice according to described application unit Layer application-specific is leading；Application unit, for carrying out time advance adjustment according to TA smooth value；Will be effectively TA population of measured values compares with predetermined number threshold value, if less than predetermined number threshold value, Then notifying that described scheduler is leading to LTE high level application-specific, wherein, Special leader refers to pre-define The targeting sequencing for non-competing Stochastic accessing.

Wherein, effective TA measured value refers to, it is thus achieved that Signal to Interference plus Noise Ratio corresponding during TA measured value is higher than predetermined Signal to Interference plus Noise Ratio thresholding；Described carry out time advance adjustment according to TA smooth value, meet including TA smooth value Issue TA to UE during regularization condition and adjust order, and exceed predetermined time threshold at TA timer Issuing to UE when value and TA smooth value are unsatisfactory for regularization condition maintains synchronize not adjust TA command process, Wherein, described predetermined time gate limit value is that TA timer period deducts a fixing non-negative time offset.

Wherein, TA smooth value meets regularization condition and refers to that once or continuous several times exceedes based on TA smooth value The condition of TA expectation adjusting range, wherein, TA expectation adjusting range refers to carry through the time of the scheduled time The interval of convergence of TA value after front adjustment.

Reference accompanying drawing 1, the basic procedure schematic diagram of the timing advance method of adjustment that the embodiment of the present invention provides, The flow process of this embodiment can be realized by base station, specifically includes following steps:

S101, TA measured value is smoothed by scheduler, and adds up effectively TA in scheduled time window length Population of measured values.Wherein, effective TA measured value refers to obtain Signal to Interference plus Noise Ratio height corresponding during TA measured value In predetermined Signal to Interference plus Noise Ratio thresholding.

Specifically, physical layer is measured by eNodeB scheduler and the TA measured value that reports is smoothed, Wherein physical layer can by the demodulated reference signal of physical uplink Traffic Channel (PUSCH), physically Row controls demodulated reference signal or detection reference signal (Sounding) the acquisition TA of channel (PUCCH) Measured value.

Time counter is set, the effective TA population of measured values in statistics scheduled time window length, wherein, time Between the initial time of counter zero setting be that eNodeB issues accidental access response in UE initial access process Moment, and zero setting after reaching scheduled time window length.

Wherein it is possible to use following formula to be smoothed:

TASoomthed_k=(1-α) TAMeasured_k-1+α·TAMeasured_k

Wherein, TAMeasured_kRepresent kth effective TA measured value, TASoomthed_kRepresent that kth TA is put down Sliding value, α represents forgetting factor, and 0≤α≤1.

S102, carries out time advance adjustment according to TA smooth value.

Specifically, carry out time advance adjustment according to TA smooth value, meet including TA smooth value and adjust bar Issue TA to UE during part and adjust order, and exceed predetermined time threshold and TA at TA timer and put down Issuing to UE when sliding value is unsatisfactory for regularization condition maintains synchronize not adjust TA command process.

Wherein, TA smooth value meets regularization condition and refers to that once or continuous several times exceedes based on TA smooth value The condition of TA expectation adjusting range.

Wherein, scheduled time thresholding is to deduct a fixing non-negative time offset by TA timer period Obtain.

Wherein, TA expectation adjusting range refers to the convergence of TA value after time advance after a while adjusts Interval.

For the uplink loss preventing TA timer expiry from causing, need in TA timer predetermined time Thresholding and time now TA smooth value is unsatisfactory for regularization condition, issues a unregulated timing advance to UE Adjust order.

S103, effective TA population of measured values of statistics compares with predetermined number threshold value.If do not surpassed Cross predetermined number threshold value, then perform step S104；Otherwise, step S111 is performed.

S104: scheduler is leading to high-rise application-specific.

Wherein, this Special leader refers to the predefined targeting sequencing for non-competing Stochastic accessing.? In LTE, high level carry out leading management and distribution.

S105: judge whether that application is to Special leader: if application is arrived, then perform step S106；If Apply for less than, then perform step S108.

S106: issue Special leader to UE, notice UE initiates Stochastic accessing.

Specifically, eNodeB controls instruction (Downlink Control Indication, DCI) by descending 1A issues the configuration index of Special leader and Stochastic accessing to UE, and notice UE initiates Stochastic accessing. UE, after receiving DCI 1A, initiates Stochastic accessing in the corresponding time with corresponding form.

S107: after receiving the accidental access signal of UE, issues accidental access response, and forwards step to S111。

Specifically, after UE receives DCI1A, Stochastic accessing can be initiated；ENodeB receives the random of UE Access after signal, issue accidental access response message, including timing adjustment information, uplink authorization and interim C-RNTI (Cell Radio Network Temporary Identifier, Cell Radio Network Temporary Identifier/Identity, Cell-RNTI).

S108: judge whether TA timer exceedes scheduled time thresholding, if be less than, the most directly returns Step 101；If it does, then issue unregulated TA order, it is then back to step 101；

S109: terminate.

In sum, according to the time advance method of adjustment for LTE and the device of the present invention, according to TA The sharpening result of measured value and effective TA population of measured values statistics, when obtaining less effective TA measured value By triggering non-competing random access procedure, smoothed by TA when obtaining more effective TA measured value Value carries out time advance adjustment, substantially increases the precision that time advance adjusts, it is to avoid measure at effective TA When being worth less, TA smooth value cannot reflect that actual TA value changes, and carries based on this smooth value time of carrying out Front adjustment is inaccurate, the problem even introducing ISI, it is achieved maintenance uplink synchronous rapidly and efficiently, thus Improve throughput of system eventually.

Be above to make those of ordinary skill in the art understand the present invention, and the present invention is carried out detailed Describe, however, it is contemplated that can also be made it in the range of the claim without departing from the present invention is contained Changing and modifications of it, these change and modifications the most within the scope of the present invention.

Claims

1. the time advance method of adjustment for Long Term Evolution LTE, it is characterised in that include following Step:

B, carry out time advance adjustment according to TA smooth value；

2. the time advance method of adjustment for LTE as claimed in claim 1, it is characterised in that In described step A, effective TA measured value refers to, it is thus achieved that Signal to Interference plus Noise Ratio corresponding during TA measured value is higher than Predetermined Signal to Interference plus Noise Ratio thresholding.

3. the time advance method of adjustment for LTE as claimed in claim 1, it is characterised in that In described step B, carry out time advance adjustment according to TA smooth value, meet including TA smooth value and adjust During condition to UE issue TA adjust order, and TA timer exceed predetermined time gate limit value and Issuing to UE when TA smooth value is unsatisfactory for regularization condition maintains synchronize not adjust TA command process.

4. the time advance method of adjustment for LTE as claimed in claim 3, it is characterised in that institute State TA smooth value meet regularization condition refer to based on TA smooth value once or continuous several times more than TA expect The condition of adjusting range, wherein, TA expectation adjusting range refers to that the time advance through the scheduled time adjusts The interval of convergence of rear TA value.

5. the time advance method of adjustment for LTE as claimed in claim 3, it is characterised in that institute Stating predetermined time gate limit value is that TA timer period deducts a fixing non-negative time offset.

6. the time advance method of adjustment for LTE as according to any one of claim 1 to 5, its It is characterised by, after described step D, farther includes: judge whether that Special leader is arrived in application, as Fruit is, then perform step E；Otherwise, step G is performed；

E, issuing Special leader to UE, notice UE initiates Stochastic accessing, then performs step F；

F, after receiving the accidental access signal of UE, issue accidental access response, then method terminates；

7. the time advance adjusting apparatus for Long Term Evolution LTE, it is characterised in that include scheduling Device and application unit, wherein,

Described scheduler, for being smoothed Timing Advance TA measured value, and adds up pre-timing Between effective TA population of measured values in window length；And it is high-rise to LTE for the notice according to described application unit Application-specific is leading；

Described application unit, for carrying out time advance adjustment according to TA smooth value；Effective TA is measured Value number compares with predetermined number threshold value, if less than predetermined number threshold value, then notified Described scheduler is leading to LTE high level application-specific, wherein, Special leader refer to predefined for The targeting sequencing of non-competing Stochastic accessing.

8. the time advance adjusting apparatus for Long Term Evolution LTE as claimed in claim 7, its feature It is,

Described effective TA measured value refers to, it is thus achieved that Signal to Interference plus Noise Ratio corresponding during TA measured value is higher than predetermined letter Dry making an uproar compares thresholding；

Described carry out time advance adjustment according to TA smooth value, when meeting regularization condition including TA smooth value Issue TA to UE and adjust order, and exceed predetermined time gate limit value and TA at TA timer and smooth Issuing to UE when value is unsatisfactory for regularization condition maintains synchronize not adjust TA command process, wherein, described Predetermined time gate limit value is that TA timer period deducts a fixing non-negative time offset.

9. the time advance adjusting apparatus for Long Term Evolution LTE as claimed in claim 7, its feature Being, described TA smooth value meets regularization condition and refers to that once or continuous several times exceedes based on TA smooth value The condition of TA expectation adjusting range, wherein, TA expectation adjusting range refers to carry through the time of the scheduled time The interval of convergence of TA value after front adjustment.

10. the time advance for Long Term Evolution LTE as according to any one of claim 7 to 9 adjusts Device, it is characterised in that farther include judging unit, is used for judging whether application unit applies for special Leading, if application to; issue Special leader to UE, notice UE initiation Stochastic accessing, and receiving After the accidental access signal of UE, issue accidental access response；If not applying for arriving, then judge TA timing Whether device exceedes scheduled time thresholding, if it does, then issue unregulated TA order, then notifies to adjust Timing Advance TA measured value is smoothed by degree device, and adds up effectively TA in scheduled time window length Population of measured values；If be less than, the most directly Timing Advance TA measured value is put down by notice scheduler Sliding process, and add up in scheduled time window length effectively TA population of measured values.