CN103841633A

CN103841633A - TD-LTE automatic gain control method and device

Info

Publication number: CN103841633A
Application number: CN201210490955.0A
Authority: CN
Inventors: 唐凯; 谢一宁; 李焱
Original assignee: ZTE Corp
Current assignee: Sanechips Technology Co Ltd
Priority date: 2012-11-27
Filing date: 2012-11-27
Publication date: 2014-06-04
Anticipated expiration: 2032-11-27
Also published as: CN103841633B; WO2014082504A1

Abstract

The invention provides a TD-LTE automatic gain control method. According to the TD-LTE automatic gain control method, average power of corresponding symbols in each TD-LTE frame is calculated with the frame size as the unit in the frequency point scanning and main synchronous symbol SS detection stage, with half of the frame size as the unit in the auxiliary synchronous symbol SSS detection and PBCH reading stage, and with the subframe length as the unit in the downlink service channel receiving stage; the most reasonable power gain control values in all stages can be obtained by comparing the average power with a power upper limit and/or power lower limit, a first target power value and a second target power value. The invention further provides a TD-LTE automatic gain control device. According to the TD-LTE automatic gain control method, the environmental characteristics of the three stages are distinguished, and the flexibility of power control is improved.

Description

A kind of TD-LTE auto gain control method and equipment

Technical field

The present invention relates to Long Term Evolution (LTE, Long Term evolution) wireless communication technology, be specifically related to a kind of time-division Long Term Evolution (TD-LTE, Time Division Long Term Evolution) automatic gain control (AGC, Automatic Gain Control) method and apparatus.

Background technology

LTE is the third generation (3G, Third Generation) evolution of mobile communication system, because using OFDM (OFDM, Orthogonal Frequency Division Multiplexing) core technology such as technology and multiple-input and multiple-output (MIMO, Multiple-Input Multiple-Out-put) technology can be counted as accurate 4G technology.LTE system can provide the peak rate of descending 100Mbps, up 50Mbps under 20MHz spectral bandwidth, can improve the performance of Cell Edge User, improves cell capacity.

At present, LTE system comprises TD-LTE and Frequency Division Duplexing (FDD) Long Term Evolution (FDD-LTE, FrequencyDivision Duplexing Long Term evolution), because TD-LTE can carry out with identical frequency the transmission of data in uplink downlink, can save band resource, and more be subject to researcher's favor.

In TD-LTE system, a TD-LTE frame is 10ms, can be divided into the field of two 5ms, and the field of each 5ms can be made up of the subframe of 5 1ms, and the subframe of each 1ms has a uniquely identified frame number.

In prior art, in TD-LTE down link signal processing procedure, comprise following three phases: frequency point scanning and main synchronizing symbol (PSS, Primary Synchronization Signal) detection-phase, auxiliary synchronizing symbol (SSS, Secondary Synchronization Signal) detect and Physical Broadcast Channel (PBCH, Physical Broadcasting Channel) fetch phase, the downlink traffic channel reception stage; Wherein, frequency point scanning is mainly used in the signal power mean value in main diversity antenna, power maximum and power minimum to scan and investigate interference signal, by the investigation to interference signal, PSS detects and determines the position of PSS symbol in TD-LTE half frame length, and now UE can know 5ms synchronizing information; SSS detects for determining that SSS symbol is in the position of frame length, and now UE can know 10ms synchronizing information, meanwhile, and the readable taking-up of PBCH TD-LTE frame number synchronization information; Described 5ms synchronizing information, 10ms synchronizing information and frame number synchronization information aggregate become TD-LTE downlink synchronization information, frame synchronization information can make subscriber equipment (UE, UserEquipment) be received smoothly under base station and be signaled by downlink traffic channel.

In above-mentioned three phases, the signal that send base station unavoidable meeting when processing layer by layer adds interference, and then has weakened the intensity of signal, for guaranteeing to signal and can arrive smoothly UE under base station, all can introduce certain Poewr control method in this three phases.In prior art, customary means is same Poewr control method to be incorporated into respectively to each stage guarantee signal strength signal intensity stability, but but ignore the feature of the signal environment of living in of this three phases, so, same Poewr control method is applied to these three different stages and will seems dumb, therefore in the urgent need to a kind of can flexible Application to the Poewr control method of this three phases.

Summary of the invention

In view of this, main purpose of the present invention is to provide a kind of TD-LTE auto gain control method and equipment, can solve the inflexible problem of Poewr control method in prior art.

For achieving the above object, technical scheme of the present invention is achieved in that

The invention provides a kind of TD-LTE auto gain control method, described method comprises:

Respectively at frequency point scanning and main synchronizing symbol PSS detection-phase take frame length as unit, auxiliary synchronizing symbol SSS detect and Physical Broadcast Channel PBCH fetch phase take half frame length as unit, downlink traffic channel receives the stage take subframe length as unit, the average power of respective symbol in each TD-LTE frame is calculated; By the comparison of described average power and power upper limit and/or power lower limit, first object performance number, the second target power value, draw the most reasonable power gain control value in each stage respectively.

In such scheme, at described frequency point scanning and PSS detection-phase, described method comprises:

Take each Symbol average performance number definite maximum average power value of 10ms frame length current TD-LTE frame as unit calculates, maximum average power value and power upper limit and/or power lower limit are compared, according to comparative result, export current TD-LTE frame and detect and PBCH fetch phase or carry out the processing of next TD-LTE frame to SSS at this stage power gain control value.

In such scheme, detect and PBCH fetch phase at described SSS, described method comprises:

Received power gain control value, take 5ms half frame length of TD-LTE frame as unit calculates current field PSS symbol, SSS Symbol average performance number, the current field PSS symbol, SSS Symbol average performance number and the first object performance number that calculate are compared, according to comparative result upgrade and export current field this stage power gain control value to downlink traffic channel receive the stage carry out the processing of next field simultaneously or carry out the processing of next field.

In such scheme, receive the stage in described downlink traffic channel, described method comprises:

Received power gain control value, take the 1ms subframe length of TD-LTE frame as unit, to calculate current subframe RS Symbol average performance number, and the current subframe RS Symbol average performance number and the second target power value that calculate are compared, upgrade current subframe at this stage power gain control value and notify to current user equipment UE or carry out the processing of next subframe according to comparative result.

In such scheme, described method comprises:

The power gain scope that received RF chip is indicated, and power gain scope is on average divided into multiple subsegments, obtain average power change in gain amount;

The value that the first frame initial power yield value that renewal current UE receives is minimum gain value, utilize average power calculating method, calculate each Symbol average performance number in the first frame length, relatively and find out maximum average power content, as the first frame maximum average power value;

In the time that the first frame maximum average power value is greater than power upper limit, upgrade the first frame initial power yield value, as the second frame initial power yield value;

Be less than under power in limited time when the first frame maximum average power value is less than power upper limit simultaneously, upgrade the first frame initial power yield value, as the second frame initial power yield value;

Be greater than under power in limited time when the first frame maximum average power value is less than power upper limit simultaneously, upgrade the first frame initial power yield value, as the second frame initial power yield value;

Output to described PSS detects and PBCH fetch phase the first frame maximum average power value as the second frame power gain control value;

Utilize average power calculating method, calculate each Symbol average performance number in the second frame length, relatively and find out maximum average power content, as the second frame maximum average power value,

In the time that the second frame maximum average power value is greater than power upper limit, upgrade the second frame initial power yield value, as the 3rd frame initial power yield value;

Be less than under power in limited time when the second frame maximum average power value is less than power upper limit simultaneously, upgrade the second frame initial power yield value, as the 3rd frame initial power yield value;

Be greater than under power in limited time when the second frame maximum average power value is less than power upper limit simultaneously, upgrade the second frame initial power yield value, as the 3rd frame initial power yield value;

Output to described PSS detects and PBCH fetch phase the second frame maximum average power value as the second frame power gain control value;

By that analogy, until complete all frames that UE receives.

In such scheme, described method comprises:

Receive the power stage controlling value of being sent by described frequency point scanning and PSS detection-phase present frame, and as present frame the first field initial power yield value;

According to average power calculating method, calculate the first field PSS symbol, the average power of SSS symbol in frequency domain, carry out filtering via loop filtering circuit, now average power content is as present frame the first field average power content;

Judge whether the first field average power content equates with first object performance number, in the time that the first field average power content equates with first object performance number, enter present frame the second field processing; When the first field average power content and first object performance number are when unequal, upgrade the first field average power yield value, as current field power gain control value, output to described downlink traffic channel and receive the stage, enter simultaneously present frame the second field is processed;

Described entering is treated to present frame the second field:

According to average power calculating method, calculate the second field PSS symbol, the average power of SSS symbol in frequency domain, carry out filtering via loop filtering circuit, now average power content is as the second field average power content;

Judge whether the second field average power content equates with first object performance number, in the time that the second field average power content equates with first object performance number, enter present frame the 3rd field processing; When the second field average power content and first object performance number are when unequal, upgrade the second field average power yield value, as current field power gain control value, output to described downlink traffic channel and receive the stage, enter simultaneously present frame the 3rd field is processed;

By that analogy, until complete all fields that UE receives.

In such scheme, described method comprises:

The described downlink traffic channel reception stage receives the current field power gain control value by described PSS detects and PBCH fetch phase sends, and current field power gain control value is carried out to variable bandwidth processing, the first subframe initial power yield value using current field power gain control value after treatment as current field;

According to average power calculating method, calculate the average power of the first subframe RS symbol in frequency domain, after loop filtering circuit filtering, now average power content is current field the first subframe average power content;

Relatively whether the first subframe average power content equates with the second target power value, in the time that the first subframe average power content equates with the second target power value, enters current field the second subframe processing; When the first subframe average power content and the second target power value are when unequal, upgrade the first subframe average power yield value, as current subframe power gain control value, notice is to current UE; Meanwhile, enter current field the second subframe processing;

Described entering is treated to current field the second subframe:

According to average power calculating method, calculate the average power of the second subframe RS symbol in frequency domain, after loop filtering circuit filtering, now average power content is current field the second subframe average power content;

Relatively whether the second subframe average power content equates with the second target power value, in the time that the second subframe average power content equates with the second target power value, enters the 3rd subframe processing of current field; When the second subframe average power content and the second target power value are when unequal, upgrade the second subframe average power yield value, as current subframe power gain control value, notice is to current UE; Meanwhile, enter the 3rd subframe processing of current field;

By that analogy, until complete all subframes that current UE receives.

The present invention also provides a kind of TD-LTE automatic gain control apparatus, and described equipment comprises: first stage power gain control module, second stage power gain control module, phase III power gain control module and loop filtering circuit; Wherein,

Described first stage power gain control module, be used for take 10ms frame length as unit, calculate each Symbol average performance number of current TD-LTE frame and determine maximum average power value, maximum average power value and power upper limit and/or power lower limit are compared, draw the most reasonable power gain control value of this stage;

Described second stage power gain control module, for take 5ms half frame length of TD-LTE frame as unit, calculate the average power content of current field PSS symbol, SSS symbol, and the current field PSS symbol calculating, average power content and the first object performance number of SSS symbol are compared, draw the most reasonable power gain control value of this stage;

Described phase III power gain control module, for take the 1ms subframe length of TD-LTE frame as unit, calculate the average power content of current subframe RS symbol, and the average power content of the current subframe RS symbol calculating and the second target power value are compared, draw the most reasonable power gain control value of this stage;

Described loop filtering circuit, carries out filtering for the average power content that second stage power gain control module and phase III power gain control module are calculated.

In such scheme, described first stage power gain control module comprises: first processes submodule and first upgrades output sub-module; Wherein,

Described first processes submodule, be used for take 10ms frame length as unit, calculate each Symbol average performance number of current TD-LTE frame, and each Symbol average performance number size of more current TD-LTE frame, determine present frame maximum average power value, to present frame maximum average power value and power upper limit and/or power lower limit are compared;

Described first upgrades output sub-module, be used for according to comparative result, upgrade current TD-LTE frame power gain control value, as next frame initial power yield value and send to described first and process submodule or export current TD-LTE frame power gain control value to described second stage power gain control module, the power gain control value as present frame in described first stage power gain control module;

Described first processes submodule, also, for after the next frame initial power yield value receiving from described the first renewal output sub-module, starts to carry out next frame processing.

In such scheme, described second stage power gain control module comprises: second processes submodule and second upgrades output sub-module;

Described second processes submodule, for take 5ms frame length as unit, calculates current field PSS symbol, SSS Symbol average performance number; And the current field PSS symbol, SSS Symbol average performance number and the first object performance number size that relatively calculate;

Described second upgrades output sub-module, be used for according to comparative result, upgrade current field power gain value and output to described phase III power gain control module, notify described the second processing submodule to carry out next field processing simultaneously or notify described the second processing submodule to carry out next field processing;

Described second processes submodule, also, for receiving after the notice of being sent by described the second renewal output sub-module, starts next field to process.

In such scheme, described phase III power gain control module comprises: the 3rd processes submodule and the 3rd upgrades output sub-module; Wherein,

The described the 3rd processes submodule, for calculating current subframe reference signal RS Symbol average performance number, and the current subframe RS Symbol average performance number relatively calculating and the second target power value size;

The described the 3rd upgrades output sub-module, be used for according to comparative result, upgrade current subframe power gain control value, and notice is to current UE, notifies described the 3rd processing submodule to carry out next subframe processing simultaneously or notifies described the 3rd processing submodule to carry out next subframe processing;

The described the 3rd processes submodule, also, for after receiving the notice of being sent by described the 3rd renewal output sub-module, starts next subframe to process.

TD-LTE auto gain control method provided by the invention and equipment, for the environmental quality of included three phases in TD-LTE down link signal processing procedure, respectively take frame length, half frame length, subframe length as unit, average power to the respective symbol in each TD-LTE frame is calculated, and respectively by the comparison of described average power and power upper limit and/or power lower limit, first object performance number, the second target power value, draw the most reasonable power gain control value in each stage; The present invention has distinguished the environmental quality of included three phases in TD-LTE down link signal processing procedure, has increased the flexibility of power control.

Accompanying drawing explanation

Fig. 1 is the realization flow schematic diagram of TD-LTE auto gain control method of the present invention;

Fig. 2 is the realization flow schematic diagram at frequency point scanning and PSS detection-phase TD-LTE auto gain control method of the present invention;

Fig. 3 is the realization flow schematic diagram at SSS detection and PBCH fetch phase TD-LTE auto gain control method of the present invention;

Fig. 4 receives the realization flow schematic diagram of stage TD-LTE auto gain control method of the present invention in downlink traffic channel;

Fig. 5 is the composition structural representation of TD-LTE automatic gain control apparatus of the present invention.

Embodiment

TD-LTE auto gain control method provided by the invention, described method comprises:

Respectively at frequency point scanning and PSS detection-phase take frame length as unit, SSS detect and PBCH fetch phase take half frame length as unit, downlink traffic channel receives the stage take subframe length as unit, the average power of respective symbol in each TD-LTE frame is calculated; By the comparison of described average power and power upper limit and/or power lower limit, first object performance number, the second target power value, draw the most reasonable power gain control value in each stage respectively.

What here, frequency point scanning and PSS detection-phase calculated is the average power of each symbol of each TD-LTE frame; What SSS detection and PBCH fetch phase calculated is the PSS symbol in each TD-LTE field, the average power of SSS symbol; What the downlink traffic channel reception stage calculated is the average power of RS symbol in each TD-LTE subframe.

As shown in Figure 1, described method specifically comprises step 10, step 20 and step 30:

Step 10: take each Symbol average performance number definite maximum average power value of 10ms frame length current TD-LTE frame as unit calculates, and the maximum average power value calculating and power upper limit and/or power lower limit are compared, export current TD-LTE frame according to comparative result and detect and PBCH fetch phase or carry out next TD-LTE frame processing to SSS at this stage power gain control value;

Here, for the environmental quality of frequency point scanning and PSS detection-phase, take 10ms frame length as unit;

Concrete, due to for frequency point scanning and PSS detection-phase, current UE does not also get any synchronizing information, so, be in the time of 10ms at a TD-LTE frame length, up, downstream signal in whole community are all likely estimated as average power by current UE.So, for the environmental quality that this stage has, adopt the method for AGC of statistics a kind of, can obtain good power gain control.

Current UE received RF circuit signal, described radio circuit includes power amplifier, analog to digital converter (ADC, Analog Digital Conversion), radio frequency chip etc.; Wherein, the power gain scope that this radio frequency chip is applicable has been indicated in the time that described radio frequency chip dispatches from the factory by radio frequency chip production firm: from minimum gain value G_min to maxgain value G_max; Described power gain scope is because of the model difference difference of radio frequency chip, also because production firm is different.

As shown in Figure 2, the concrete processing procedure of step 10 can be:

The power gain scope M that radio frequency chip is indicated is on average divided into N subsegment, and the average power gain of each subsegment is M/N (db), and using M/N (db) as average power change in gain amount, wherein, N is positive integer;

Here, the number of supposing all TD-LTE frames that current UE receives is i, and i is positive integer, so, all TD-LTE frames that receive can be arranged as to the first frame, the second frame ... i frame;

First the first frame is processed, upgrading the first frame initial power yield value A_G (1) is the value of minimum gain value G_min;

The first frame power gain initial value A_G (1) is updated in average power value calculating method of the prior art, calculates each Symbol average performance number in the first frame length;

Relatively each Symbol average performance number size in the first frame length, and find out maximum average power value, as the first frame maximum average power value;

Relatively the first frame maximum average power value and power upper limit P _maxlimsize, when the first frame maximum average power value is greater than power upper limit P _maxlimtime, upgrade first frame initial power yield value A_G (2)=A_G (1)+M/N, as the second frame initial power yield value, enter the second frame processing; When the first frame maximum average power value is less than power upper limit P _maxlimtime, then compare the first frame maximum average power value and power lower limit P _minlimsize;

When the first frame maximum average power value is less than power lower limit P _minlimtime, upgrade first frame initial power yield value A_G (2)=A_G (1)-M/N, as the second frame initial power yield value, enter the second frame processing; When the first frame maximum average power value is greater than power lower limit P _minlimtime, output the first frame initial power yield value A_G (1) detects and PBCH fetch phase to SSS, the power gain control value result1 as the first frame in frequency point scanning and the output of PSS detection-phase;

Described entering is specifically as follows the second frame processing:

The second frame power gain initial value A_G (2) is updated to average power value calculating method of the prior art, calculates the average power content of each symbol in the second frame length;

Compare the average power content size of each symbol in the second frame length and find out maximum average power value, as the second frame maximum average power value;

Relatively the second frame maximum average power value and power upper limit P _maxlimsize, when the second frame maximum average power value is greater than power upper limit P _maxlimtime, upgrade second frame initial power yield value A_G (3)=A_G (2)+M/N, as the 3rd frame initial power yield value, enter the 3rd frame processing; When the second frame maximum average power value is less than power upper limit P _maxlimtime, then compare the second frame maximum average power value and power lower limit P _minlimsize;

When the second frame maximum average power value is less than power lower limit P _minlimtime, upgrade second frame initial power yield value A_G (3)=A_G (2)-M/N, as the 3rd frame initial power yield value, enter the 3rd frame processing; When the second frame maximum average power value is greater than power lower limit P _minlimtime, output the second frame initial power yield value A_G (2), the power gain control value result1 as the second frame in frequency point scanning and the output of PSS detection-phase;

Described enter detailed process to the 3rd frame processing and above-mentioned enter the implementation procedure of the second frame processing similar, by that analogy, until handle all frames that current UE receives.

In step 10, described power upper limit P _maxlim, power lower limit P _minlimpre-set; For different frames, described power upper limit P _maxlim, power lower limit P _minlimdesirable identical value, also desirable different value;

Wherein, power upper limit P _maxlimspan be 10log10 (2 ^m)+15 (db), power lower limit P _minlimspan is 10log10 (2 ^m)-15 (db), m is the bit wide of ADC device; The bit wide of ADC device has been indicated bit wide scope in the time that ADC device dispatches from the factory.

In addition, the span of Parameter N is 3～6, can adjust flexibly according to actual environment (such as field testing); When actual environment requires to have compared with rapid convergence and when not high to gain accuracy area requirement, desirable N is smaller value; Otherwise desirable N is relatively large value; Because this stage is the processing that frame is carried out, therefore this stage is after each Symbol average performance number of calculating in each frame length, without carrying out filtering processing through loop filtering circuit again.

Illustrate above, after frequency point scanning and PSS detection-phase finish, can determine the position of PSS symbol in TD-LTE half frame length, determined field sync, that is to say, current UE has now been known 5ms synchronizing information, detects and PBCH fetch phase at SSS, carries out the automatic gain control of SSS detection and PBCH fetch phase by making full use of 5ms synchronizing information.

Step 20: received power gain control value, take 5ms half frame length of TD-LTE frame as unit calculates current field PSS symbol, SSS Symbol average performance number, the current field PSS symbol, SSS Symbol average performance number and the first object performance number that calculate are compared, according to comparative result upgrade and export current field this stage power gain control value to downlink traffic channel receive the stage carry out the processing of next field simultaneously or carry out the processing of next field;

Here, detect and the environmental quality of PBCH fetch phase for PSS, take 5ms half frame length of TD-LTE frame as unit;

From such scheme, can find out, frequency point scanning and PSS detection-phase are the processing of carrying out for TD-LTE frame of 10ms, and after frequency point scanning and PSS detection-phase finish, current UE has been known 5ms synchronizing information, be field sync information, determined the signal time window of PSS symbol; So, in SSS detects, can determine the signal time window of SSS symbol;

Here, the signal time window of PSS symbol and SSS symbol can be regarded two points at time coordinate axle as, that is: PSS symbol and the SSS symbol position in TD-LTE half frame length is determined, just can be by PSS symbol in half frame length and SSS symbol extraction out; Can find out thus, this stage is mainly for the processing of TD-LTE field progress row; At this, the TD-LTE frame of current 10ms is divided into the first field and the second field, described the first field and the second field are the frame length of 5ms.

As shown in Figure 3, the concrete processing procedure of step 20 can be:

Receive the result1 of frequency point scanning and the output of PSS detection-phase as this stage initial power yield value;

For TD-LTE system, first the first subframe initial power yield value using result1 as this stage, after extracting TD-LTE frame the first field PSS symbol and SSS symbol of current 10ms, utilize prior art to calculate the first field PSS symbol, the average power of SSS symbol in frequency domain, and carry out repeatedly cumulative mean, carry out filtering through loop filtering circuit again, so that filtering noise, acquired results is the first field average power content p1;

Judge whether the first field average power content p1 equates with first object performance number Target, in the time that p1 equals Target, using result1 as the second field initial power yield value, enter the processing of TD-LTE frame the second field to current t0ms; In the time that p1 is not equal to Target, upgrade the power gain control value result2=result1+ (Target-p1) of the first field in this stage, and export result2 to the downlink traffic channel reception stage, using result2 as the second field initial power yield value, enter the processing of TD-LTE frame the second field to current 10ms;

The described processing that enters TD-LTE frame the second field to current 10ms is specially: extract TD-LTE frame the second field PSS symbol and the SSS symbol of current 10ms, and utilize prior art to calculate the second field average power content p2; Then, judge that whether the second field average power content p2 equates with target power value Target, in the time that p2 equals Target, enters the first field of next TD-LTE frame; In the time that p2 is not equal to Target, upgrade the second field at this stage power gain control value result 2=p_old+ (Target-p2) and export result 2 receiving the stage to downlink traffic channel;

Here, set up and carry out to now when the condition from " when p1 is not equal to Target ", get p_old=result2; Set up and carry out to now when the condition from " when p1 equals Target ", get p_old=result1;

By that analogy, until handle all fields that current UE receives.

Here, the value of first object performance number Target will design according to saturated risk in the bit wide m of the actual ADC device of selecting in TD-LTE system and larger noise/interference situation, conventionally gets Target=2 ^m.

Meanwhile, because this stage processes for TD-LTE field, half frame time is shorter, in loop filtering circuit, need to set in advance relatively large loop filtering coefficient, to guarantee the Fast Convergent of field symbol.

Under this explanation, when technical solution of the present invention is illustrated, every loop filtering coefficient that relates to, the span of the loop filtering coefficient of getting is 0.04～0.5.

In addition, carrying out step 20 while illustrating, mainly, take the TD-LTE system of 1.4M bandwidth as example, technical scheme of the present invention includes but not limited to the TD-LTE system of 1.4M bandwidth, can also be applicable to the TD-LTE system of other bandwidth, as TD-LTE system of 10M, 15M, 20M bandwidth etc.

Step 30: received power gain control value, take the 1ms subframe length of TD-LTE frame as unit calculates current subframe RS Symbol average performance number, and the current subframe RS Symbol average performance number and the second target power value that calculate are compared, upgrade current subframe at this stage power gain control value according to comparative result, and notify current UE or carry out next subframe processing;

Here, receive the environmental quality in stage for downlink traffic channel, take the 1ms subframe length of TD-LTE frame as unit;

Receive the stage for downlink traffic channel, current UE has been known the TD-LTE downlink synchronization information such as 5ms synchronizing information, 10ms synchronizing information and frame number synchronization information, that is to say, can determine the reference signal (RS in each 1ms subframe by downlink synchronization current UE, Referenc Signal) position of symbol in subframe separately, so, just RS in each subframe can be extracted; This shows, this stage processes mainly for each 1ms subframe of TD-LTE;

At this, the TD-LTE field of current 5ms is divided into the first subframe, the second subframe, the 3rd subframe, the 4th subframe, the 5th subframe, each subframe length is 1ms.

Owing to detecting for SSS and the bandwidth in PBCH fetch phase and this stage exists different situation, this stage, because the proportional relation of power and bandwidth,, along with bandwidth increase, power is corresponding enhancing also take the TD-LTE system of 20M bandwidth as example.In order to reach, SSS detects and PBCH fetch phase is connected with the better of this stage,, need to first carry out variable bandwidth processing to the power gain control value result2 that SSS detects and PBCH fetch phase sends here.

As shown in Figure 4, the concrete processing procedure of step 30 can be:

The power gain control value result2 that SSS detects and PBCH fetch phase sends is carried out to variable bandwidth to be processed as shown in formula (1):

result2_new＝result2-10*log10(B _new/B _old)(1)

Wherein, variable B _oldfor the TD-LTE system bandwidth that SSS detects and PBCH fetch phase adopts; B _newby this stage is adopted TD-LTE system bandwidth.

Reading result2_new is the first subframe initial power yield value in this stage;

After extracting TD-LTE field the first subframe RS symbol of current 5ms, utilize prior art to calculate the average power of current field the first subframe RS symbol in frequency domain, utilize loop filtering circuit to carry out loop filtering, so that filtering noise, acquired results is the first subframe average power content M_p1;

Judge whether the first subframe average power content M_p1 equates with the second target power value Tar, in the time that M_p1 equals Tar, using result2_new as the second subframe initial power yield value, the second subframe is processed; In the time that M_p1 is not equal to Tar, upgrade the power gain control value result3=result2_new+ (Tar-M_p1) of the first subframe in this stage, and by result3 value notice current UE, take result3 as the second subframe initial power yield value, the second subframe is processed;

Wherein, described the second subframe is processed and is specifically as follows: TD-LTE field the second subframe RS symbol that extracts current 5ms, and utilize prior art to calculate the average power of the second subframe RS symbol in frequency domain, utilize loop filtering circuit to carry out loop filtering, so that filtering noise, acquired results is the second subframe average power content M_p2;

Judge whether the second subframe average power content M_p2 equates with the second target power value Tar, in the time that M_p2 equals Tar, take result2_new as the second subframe initial power yield value, the 3rd subframe is processed; In the time that M_p2 is not equal to Tar, upgrade the second subframe at this stage power gain control value result3=Y+ (Tar-M_p2), and by result3 value notice current UE, take result3 as the 3rd subframe initial power yield value, the 3rd subframe is processed;

Here, when setting up and carry out to now from " M_p1 equals Tar " condition, Y=result2_new; When setting up and carry out to now from " M_p1 is not equal to Tar " condition, Y=result3;

By that analogy, until handle each subframe that current UE receives.

In step 30, the second target power value Tar designs according to the bit wide m of the actual ADC device of selecting in TD-LTE system, conventionally gets Target=2m, and described ADC device bit wide m has indicated bit wide in the time dispatching from the factory.

Consider that this stage control frequency of requirement is higher, in loop filtering circuit, need to select compared with minor loop filter factor, to guarantee the stable of down link.

Based on above-mentioned TD-LTE auto gain control method.The present invention also provides a kind of TD-LTE automatic gain control apparatus, as shown in Figure 5, described equipment comprises: first stage power gain control module 50, second stage power gain control module 51, phase III power gain control module 52 and loop filtering circuit 53; Wherein,

Described first stage power gain control module 50, be used for take 10ms frame length as unit, calculate each Symbol average performance number of current TD-LTE frame and determine maximum average power value, maximum average power value and power upper limit and/or power lower limit are compared, draw the most reasonable power gain control value of this stage;

Described second stage power gain control module 51, for take 5ms half frame length of TD-LTE frame as unit, calculate the average power content of current field PSS symbol, SSS symbol, and the current field PSS symbol calculating, average power content and the first object performance number of SSS symbol are compared, draw the most reasonable power gain control value of this stage;

Described phase III power gain control module 52, for take the 1ms subframe length of TD-LTE frame as unit, calculate the average power content of current subframe RS symbol, and the average power content of the current subframe RS symbol calculating and the second target power value are compared, draw the most reasonable power gain control value of this stage;

Described loop filtering circuit 53, carries out filtering for the average power content that second stage power gain control module 51 and phase III power gain control module 52 are calculated.

Here, the first stage is frequency point scanning and PSS detection-phase, and second stage is that SSS detects and PBCH fetch phase, and the phase III is that downlink traffic channel receives the stage.

Concrete, described first stage power gain control module 50, the power gain scope M that received RF chip is indicated, and M is on average divided into N subsegment, using M/N (db) as average power change in gain amount; Then the value that to upgrade the first frame initial power yield value that current UE receives be minimum gain value, utilize average power calculating method of the prior art, calculate each Symbol average performance number in the first frame length, relatively and find out maximum average power content, as the first frame maximum average power value;

In the time that being greater than power upper limit, the first frame maximum average power value upgrades the first frame initial power yield value, as the second frame initial power yield value;

Be greater than under power in limited time when the first frame maximum average power value is less than power upper limit simultaneously, upgrade the first frame initial power yield value, as the second frame initial power yield value; The first frame initial power yield value outputs to described second stage power gain control module 51 as present frame power gain control value simultaneously;

According to technique scheme, the second frame that described first stage power gain control module 50 receives current UE is processed, until complete all frames that receive.

Here, power gain scope, minimum gain value have been indicated value in the time that described radio frequency chip dispatches from the factory.

Described second stage power gain control module 51 receives the present frame power stage controlling value of being sent by described first stage power gain control module 50, as present frame the first field initial power yield value;

According to prior art average power calculating method, described second stage power gain control module 51 can calculate present frame the first field PSS symbol, the average power of SSS symbol in frequency domain, then described second stage power gain control module 51 sends the average power calculating to described loop filtering circuit 53, undertaken after filtering by described loop filtering circuit 53, return to described second stage power gain control module 51, now returning to average power content is the first field average power content again;

Described second stage power gain control module 51, receives and judges whether the first field average power content equates with first object performance number;

In the time that the first field average power content equates with first object performance number, described the second power gain control module 51, the present frame power stage controlling value sending using described first stage power gain control module 50, as the second field initial power yield value, starts the second field of present frame to process according to technique scheme;

When the first field average power content and first object performance number are when unequal, described second stage power gain control module 51 is upgraded the first field average power yield value, as current field power gain control value, output to institute's phase III power control module 52; Meanwhile, using the first field average power yield value after upgrading as the second field initial power yield value, start the second field of present frame to process according to technique scheme;

According to technique scheme, described second stage power gain control module 51 is processed the second field of present frame, until handle all fields that current UE receives.

Described phase III power gain control module 52, receive and send current field power gain control value by described second stage power gain control module 51, and utilize formula (1) to carry out variable bandwidth processing to current field power gain control value, using current field power gain control value after treatment as current field the first subframe initial power yield value;

According to prior art average power calculating method, described phase III power gain control module 52 calculates the average power of the first subframe RS symbol in frequency domain, the average power that transmission calculates is to described loop filtering circuit 53, undertaken after filtering by described loop filtering circuit 53, return to described phase III power gain control module 52, now returning to average power content is the first subframe average power content again;

Relatively whether the first subframe average power content equates with the second target power value;

In the time that the first subframe average power content equates with the second target power value, using the first subframe initial power yield value as the second frame initial power yield value, described phase III power gain control module 52 starts the second subframe of current field to process according to technique scheme;

When the first subframe average power content and the second target power value are when unequal, described phase III power gain control module 52 is upgraded the first subframe average power yield value, and as current subframe power gain control value, notice is to current UE; Simultaneously, using the first subframe average power yield value after upgrading as the second frame initial power yield value, start the second subframe of current field to process according to technique scheme;

According to technique scheme, described phase III power gain control module 52 is processed the second subframe of current field, until handle all subframes that current UE receives.

Described first stage power gain control module 50 further comprises that the first processing submodule 500 and first upgrades output sub-module 501; Wherein,

Described first processes submodule 500, be used for take 10ms frame length as unit, calculate each Symbol average performance number of current TD-LTE frame, and each Symbol average performance number size of more current TD-LTE frame, determine present frame maximum average power value, to present frame maximum average power value and power upper limit and/or power lower limit are compared;

Described first upgrades output sub-module 501, be used for according to comparative result, upgrade current TD-LTE frame power gain control value, as next frame initial power yield value and send to described first and process submodule 500 or export current TD-LTE frame initial power yield value, as current TD-LTE power gain control value to described second stage power gain control module 51;

Described first processes submodule 500 also for after the next frame initial power yield value receiving from described the first renewal output sub-module 501, starts to carry out to next frame processing;

Described second stage power gain control module 51 further comprises that the second processing submodule 510 and second upgrades output sub-module 511;

Described second processes submodule 510, for take 5ms frame length as unit, calculates current field PSS symbol, SSS Symbol average performance number; And the current field PSS symbol, SSS Symbol average performance number and the first object performance number size that relatively calculate;

Described second upgrades output sub-module 511, for according to comparative result, upgrades and exports current field power gain value to described phase III power gain control module 52, notifies described the second processing submodule 510 to carry out next field processing simultaneously; Or only notify described the second processing submodule 510 to carry out next field processing;

Described second processes submodule 510 also for receiving after the notice of being sent by described the second renewal output sub-module 511, starts next field to process.

Described phase III power gain control module 52 further comprises that the 3rd processes submodule 520 and the 3rd renewal output sub-module 521; Wherein,

The described the 3rd processes submodule 520, for calculating after variable bandwidth, calculates current subframe RS Symbol average performance number, and the current subframe RS Symbol average performance number relatively calculating and the second target power value size;

The described the 3rd upgrades output sub-module 521, and for upgrade current subframe power gain control value according to comparative result, and notice is to current UE, notifies described the 3rd processing submodule 520 to carry out next subframe processing simultaneously; Or only notify described the 3rd processing submodule 520 to carry out next subframe processing;

The described the 3rd processes submodule 520 also for after receiving the notice of being sent by described the 3rd renewal output sub-module 521, starts next subframe to process.

Concrete, in the time that current UE is in frequency point scanning and PSS detection-phase, first, described first processes the power gain scope M that submodule 500 received RF chips are indicated, and M is on average divided into N subsegment, so, M/N (db) is each subsegment average power gain;

Here,, using M/N (db) as average power change in gain amount, wherein N is positive integer; Described radio frequency chip, in the time dispatching from the factory, is indicated minimum gain value G_min and maxgain value G_max;

Current UE being received to all frames and arrange in numerical order in order, is the first frame, the second frame ... i frame, and i is positive integer;

Described first processes submodule 500, first the first frame is processed, and upgrading the first frame initial power yield value A_G (1) is the value of minimum gain value G_min;

Utilize average power calculating method of the prior art, described first processes submodule 500 calculates each Symbol average performance number in the first frame length; And compare the interior each Symbol average performance number size of the first frame length and find out maximum average power value, as the first frame maximum average power value;

When the first frame maximum average power value is greater than power upper limit P _maxlimtime, described first upgrades output sub-module 501 upgrades first frame initial power yield value A_G (2)=A_G (1)+M/N, as the second frame initial power yield value, described first upgrades output sub-module 501 outputs to described the first processing submodule 500 by A_G now (2);

When the first frame maximum average power value is less than power upper limit P _maxlimtime, first processes submodule 500 compares the first frame maximum average power value and power lower limit P again _minlimsize,

When the first frame maximum average power value is less than power lower limit P _minlimtime, described first upgrades output sub-module 501 upgrades first frame initial power yield value A_G (2)=A_G (1)-M/N, as the second frame initial power yield value, described first upgrades output sub-module 501 outputs to described the first processing submodule 500 by A_G now (2);

When the first frame maximum average power value is greater than power lower limit P _minlimtime, described the first renewal output sub-module 501 is exported A_G (1) value and is sent to described second stage power gain control module 51, specifically send to described second to process submodule 510, the power gain control value result1 as the first frame in frequency point scanning and the output of PSS detection-phase;

Described first processes submodule 500 receives A_G (2) afterwards, utilizes average power calculating method of the prior art, and described first processes submodule 500 calculates each Symbol average performance number in the second frame length; And compare the interior each Symbol average performance number size of the second frame length and find out maximum average power value, as the second frame maximum average power value;

When the second frame maximum average power value is greater than power upper limit P _maxlimtime, described first upgrades output sub-module 501 upgrades second frame initial power yield value A_G (3)=A_G (2)+M/N, as the 3rd frame initial power yield value, described first upgrades output sub-module 501 outputs to described the first processing submodule 500 by A_G now (3);

When the second frame maximum average power value is less than power upper limit P _maxlimtime, first processes submodule 500 compares the second frame maximum average power value and power lower limit P again _minlimsize,

When the second frame maximum average power value is less than power lower limit P _minlimtime, described first upgrades output sub-module 501 upgrades second frame initial power yield value A_G (3)=A_G (2)-M/N, as the 3rd frame initial power yield value, described first upgrades output sub-module 501 outputs to described the first processing submodule 500 by A_G now (3);

When the first frame maximum average power value is greater than power lower limit P _minlimtime, described the first renewal output sub-module 501 is exported A_G (2) value and is sent to described second stage power gain control module 51, specifically send to described second to process submodule 510, the power gain control value result1 exporting in first stage power gain control module 50 as the second frame;

According to technique scheme, described first processes submodule 500 is receiving A_G (3) afterwards, completes the processing to the 3rd frame in conjunction with the first renewal output sub-module 501, by that analogy, until complete, current UE is received to all frame processing.

Here described power upper limit P, _maxlim, power lower limit P _minlimin described first stage power gain control module 50, pre-set, concrete in described first processes submodule 500, arrange; For different frames, described power upper limit P _maxlim, power lower limit P _minlimalso desirable different value of desirable identical value;

Wherein, power upper limit P _maxlimspan be 10log10 (2 ^m)+15 (db), power lower limit P _minlimspan is 10log10 (2 ^m)-15 (db), m is the bit wide of ADC device in radio circuit; The signal that described radio circuit sends is received by current UE;

In addition, the span of Parameter N is 3～6, in described first stage power gain control module 50, pre-sets, and specifically in described first processes submodule 500, arranges; Because this stage is the processing that frame is carried out, calculate after the average power content of each symbol in every frame length therefore process submodule 500 described first, carry out filtering processing without again each Symbol average performance number calculating being sent to described loop filtering circuit 53.

Current UE in PSS detect and PBCH fetch phase in time, it is initial power yield value that described the second processing submodule 510 receives the result1 that first stage power gain control module 50 sends;

This stage, current UE can be known the synchronizing information of 5ms, therefore described second stage power gain control module 51 can be determined PSS symbol in each field, SSS character position, and then can extract and calculate PSS symbol in each field, SSS Symbol average performance number;

The TD-LTE frame receiving take current UE is example, this TD-LTE frame can be divided into the first field, the second field;

Described second processes submodule 510, receive the result1 being sent by first stage power gain control module 50 as the first field initial power yield value, foundation is by result1 substitution prior art average power calculating method, calculate the first field PSS symbol, the average power of SSS symbol in frequency domain, then described the second processing submodule 510 sends the average power calculating to described loop filtering circuit 53, undertaken after filtering by described loop filtering circuit 53, return to again average power and process submodule 510 to described second, now returning to average power content is the first field average power content p1,

Described second processes submodule 510 judges whether the first field average power content p1 equates with first object performance number Target,

In the time that p1 equals Target, using result1 as the second field initial power yield value, described second processes submodule 510 starts the processing to the second field;

In the time that p1 is not equal to Target, described second upgrades output sub-module 511 upgrades the first field power gain control value result2, and result2 is outputed to described phase III power control module 52, specifically outputs to the 3rd and processes submodule 520; Using result2 as the second field initial power yield value, described second upgrades output sub-module 511 notifies described the second processing submodule 510 to enter the second field processing;

Wherein, result2=result1+ (Target-p1);

Described second processes submodule 510 receives notice rear (result2 is as the second field initial power yield value) or self identifies (result1 is as the second field initial power yield value) and need to carry out after next field processing, start the second field to process: the second field initial power yield value is updated to prior art average power calculating method and calculates the second field PSS symbol, the average power of SSS symbol in frequency domain, then described the second processing submodule 510 sends the average power calculating to described loop filtering circuit 53, undertaken after filtering by described loop filtering circuit 53, return to again average power and process submodule 510 to described second, now returning to average power content is the second field average power content p2,

Described second processes submodule 510 judges whether the second field average power content p1 equates with first object performance number Target,

In the time that p2 equals Target, using the second field initial power yield value as the 3rd field initial power yield value, described second processes submodule 510 starts the 3rd field to process;

In the time that p2 is not equal to Target, described second upgrades output sub-module 511 upgrades the first field power gain control value result2, result2=p_old+ (Target-p1), and result2 is outputed to described phase III power gain control module 52, specifically output to the 3rd and process submodule 520; Described second upgrades output sub-module 511 notifies described second to process the processing that submodule 510 enters the first field to next frame;

Wherein, set up and carry out to now when the condition from " when p1 is not equal to Target ", get p_old=result2; Set up and carry out to now when the condition from " when p1 equals Target ", get p_old=result1;

According to technique scheme, described the second processing submodule 510 receives to be notified rear or self identifies and need to carry out after next frame the first field, with described the second renewal output sub-module 511 combinations, completes the processing that next frame the first field is carried out; Until handle all fields that current UE receives.

Here, first object performance number Target pre-sets in described second stage power gain control module 51, is specifically arranged on described second and processes in submodule 510.

In the time that current UE is in the downlink traffic channel reception stage, current UE can be known synchronizing information and the frame number synchronization information of 5ms synchronizing information, 10ms, therefore described phase III power gain control module 52 can be determined RS character position in each subframe, and then can extract and calculate each subframe RS Symbol average performance number;

The TD-LTE field receiving take current UE is example, this TD-LTE field can be divided into the first subframe, the second subframe, the 3rd subframe, the 4th subframe, the 5th subframe;

The bandwidth of working with described phase III power gain control module 52 because of described second stage power gain control module 51 has not identical situation, so, the described the 3rd processes submodule 520 receives after the power gain control value result2 of described second stage power gain control module 51, first do variable bandwidth processing according to formula (1), then read and finish variable bandwidth result2_new after treatment as the first subframe initial power yield value;

The described the 3rd processes submodule 520, by result2_new substitution prior art average power calculating method, calculate the average power of the first subframe RS symbol in frequency domain, then described the 3rd processing submodule 520 sends the average power calculating to described loop filtering circuit 53, undertaken after filtering by described loop filtering circuit 53, return to average power again and process submodule 520 to the described the 3rd, now returning to average power content is the first subframe average power content M_p1;

Next, the described the 3rd processes submodule 520 judges whether the first subframe average power content M_p1 equates with the second target power value Tar,

In the time that M_p1 equals Tar, using result2_new as the second subframe initial power yield value, the 3rd process submodule 520 start the processing to the second subframe;

In the time that M_p1 is not equal to Tar, the described the 3rd upgrades output sub-module 521 upgrades the first subframe power gain control value result3=result2_new+ (Tar-M_p1), and result3 is notified to current UE; Using result3 as the second field initial power yield value, the described the 3rd upgrades output sub-module 521 notifies described the 3rd processing submodule 520 to enter the second subframe processing;

The described the 3rd processes submodule 520 docks notified (using result3 as the second field initial power yield value) or self identifies (using result2_new as the second field initial power yield value) and need to carry out after next subframe processing, upgrades output sub-module start the second subframe to process to 521 in conjunction with the described the 3rd:

The described the 3rd processes submodule 520, according to prior art average power calculating method, calculate the average power of the second subframe RS symbol in frequency domain, then described the 3rd processing submodule 520 sends the average power calculating to described loop filtering circuit 53, undertaken after filtering by described loop filtering circuit 53, return to average power again and process submodule 520 to the described the 3rd, now returning to average power content is the second subframe average power content M_p1;

Next, the described the 3rd processes submodule 520 judges whether the second subframe average power content M_p2 equates with the second target power value Tar,

In the time that M_p2 equals Tar, using result2_new as the 3rd subframe initial power yield value, institute the 3rd processes submodule 520 and starts the 3rd subframe to process;

In the time that M_p2 is not equal to Tar, the described the 3rd upgrades output sub-module 521 upgrades the second subframe power gain control value result3=Y+ (Tar-M_p2), and result3 is notified to current UE; The described the 3rd upgrades output sub-module 521 notifies described the 3rd processing submodule 520 to enter the processing to the 3rd subframe;

Here, when setting up and carry out to now from " M_p1 equals Tar " condition, Y=result2_new; When setting up and carry out now 1 from " M_p1 is not equal to Tar " condition, Y=result3;

According to technique scheme, the described the 3rd processes submodule 520 receives after notice, with described the second renewal output sub-module 521 combinations, completes the processing that next subframe is carried out; Until handle all subframes that current UE receives.

Here, the second target power value Tar pre-sets at phase III power gain control mould 52, is specifically arranged on the described the 3rd and processes in submodule 520;

In this stage, current UE has been known the TD-LTE downlink synchronization information such as 5ms synchronizing information, 10ms synchronizing information and frame number synchronization information, that is to say and pass through downlink synchronization, the 3rd processes submodule 520 can determine reference signal RS (Referenc Signal) symbol in the each 1ms subframe position in subframe separately, so just RS in each subframe can be extracted.

TD-LTE terminal auto gain control method provided by the invention and equipment are the TD-LTE system of 1.4M, 3M, 5M, 10M, 15M, 20M applicable to bandwidth.

TD-LTE auto gain control method provided by the invention, for the environmental quality of three phases, respectively take frame length as unit, take half frame length as unit, take subframe length as unit, respective symbol average power is calculated, by the comparison of a frame length symbol maximum average power value and power upper limit and/or power lower limit, can obtain in frequency point scanning and the most rational power gain control value of PSS detection-phase; By the comparison of half frame length RSS symbol and SSS Symbol average performance number and first object performance number, can obtain detecting and the most rational power gain control value of PBCH fetch phase at SSS; By the comparison of subframe RS Symbol average performance number and the second target power value, can obtain receiving the most rational power gain control value of stage in downlink traffic channel; The present invention has distinguished the environmental quality of this three phases, adopts different power gain control methods in each stage, has improved the flexibility of power control.

The above, be only preferred embodiment of the present invention, is not intended to limit protection scope of the present invention.

Claims

1. a TD-LTE auto gain control method, is characterized in that, described method comprises:

2. TD-LTE auto gain control method according to claim 1, is characterized in that, at described frequency point scanning and PSS detection-phase, described method comprises:

3. TD-LTE auto gain control method according to claim 1, is characterized in that, detects and PBCH fetch phase at described SSS, and described method comprises:

4. TD-LTE auto gain control method according to claim 1, is characterized in that, receives the stage in described downlink traffic channel, and described method comprises:

5. TD-LTE auto gain control method according to claim 2, is characterized in that, described method comprises:

By that analogy, until complete all frames that UE receives.

6. TD-LTE auto gain control method according to claim 3, is characterized in that, described method comprises:

Described entering is treated to present frame the second field:

By that analogy, until complete all fields that UE receives.

7. TD-LTE auto gain control method according to claim 4, is characterized in that, described method comprises:

Described entering is treated to current field the second subframe:

By that analogy, until complete all subframes that current UE receives.

8. a TD-LTE automatic gain control apparatus, is characterized in that, described equipment comprises: first stage power gain control module, second stage power gain control module, phase III power gain control module and loop filtering circuit; Wherein,

9. TD-LTE automatic gain control apparatus according to claim 8, is characterized in that, described first stage power gain control module comprises: first processes submodule and first upgrades output sub-module; Wherein,

Described first upgrades output sub-module, be used for according to comparative result, upgrade current TD-LTE frame power gain control value, as next frame initial power yield value and send to described first and process submodule or export current TD-LTE frame power gain control value to described second stage power gain control module, the power gain control value as present frame in first stage power gain control module;

10. TD-LTE automatic gain control apparatus according to claim 8, is characterized in that, described second stage power gain control module comprises: second processes submodule and second upgrades output sub-module;

11. TD-LTE automatic gain control apparatus according to claim 8, is characterized in that, described phase III power gain control module comprises: the 3rd processes submodule and the 3rd upgrades output sub-module; Wherein,