CN101207418A - Method and apparatus of data rate control - Google Patents

Abstract

The invention discloses a data velocity control method, which conducts flux control, grouping, compression repeat, and modulation on the signal data on the basis of the prior interlaced frequency division multiple-address access technology. Simultaneously, the invention also discloses a data velocity control device which includes a flux control module, a grouping module, a compression repeat module and a modulation module. According to the requirement of the system, by conducting the flux control, the grouping, the compression repeat, and the modulation on the signal data, the invention ensures a system to keep relatively higher data velocity always under same channel qualities, and can lower the falling speed of the data velocity.

Description

A kind of data rate control method and device

Technical field

The present invention relates to communication technical field, be meant a kind of data rate control method and device especially.

Background technology

Along with the continuous development of mobile communication technology and Internet technology, mobile communication and the Internet merge gradually mutually, insert the Internet as people by portable terminal and enjoy multiple service.For can satisfy increase rapidly for the high-speed mobile data, services, the demand of mobile Internet business particularly, at third generation cooperative programme (3GPP, 3rd Generation Partnership Project) high speed downlink packet access (HSDPA, High Speed Downlink Packet Access) technology has been proposed in the 5th edition.In the HSDPA technology, for the transfer of data of two-forty is provided, must change traditional channel adaptive technique, therefore Adaptive Modulation and Coding (AMC, Adaptive Modulation and Coding) technology has been proposed.

The AMC technology belongs to a kind of link adaptation techniques, by changing the variation that transmission parameter comes the compensate for channel condition.The basic principle of AMC technology is in the system constraint scope, and according to the change adjustment modulation and the coded system of channel quality status, channel quality status is obtained by the feedback of receiver.In a communication system of using the AMC technology, the user who sits pretty can be endowed higher modulation and coded system; And be in the user of unfavorable position, then can be endowed lower modulation and coded system.As for the very near user in distance base station, can adopt quadrature amplitude modulation (64QAM, the 64Quadrature Amplitude Modulation) mode of 64 states, and, but adopt the orthogonal PSK modulation system for the user who is in cell boarder.The AMC The Application of Technology makes the user who sits pretty can obtain higher data rate, thereby increases the throughput of sub-district.In addition, in the link circuit self-adapting process, owing to be not by adjusting transmitting power, adapt to, having reduced the interference in the system but carry out channel by adjustment modulation and coded system.

But, still there is deficiency in present AMC technology, under the situation of channel quality deterioration, change chnnel coding and also can't reach the corresponding error rate (BER, Bit Error Rate) when requiring, the modulation system of communication system will be reduced to the quadrature amplitude modulation (16QAM of 16 states from 64QAM, 16QuadratureAmplitude Modulation), if still can't reach corresponding BER, then further reduce to 4 state phase shift keyings (4PSKP, 4Phase-Shift-Keying).Though change the error rate that modulation system can satisfy system requirements, but it can cause the reduction of system data rates, supposing the system adopts the 64QAM modulation system, and the data rate when not passing through the method for adjusting subcarrier spacing is 100%, if reduce to the 16QAM modulation system, then system data rates is reduced to 66.67% of initial rate.This shows that this technology constantly changes modulation system in order to satisfy the requirement of the error rate, cause the very fast of signal rate decline.

Summary of the invention

The object of the present invention is to provide a kind of data rate control method, make system under the situation of channel quality deterioration, slow down the decrease speed of data rate, and keep relative higher data speed.

Based on above-mentioned purpose, embodiments of the present invention provide a kind of data rate control method, comprising:

To import data according to the data rate of system requirements and be divided into more than one group;

Multi-group data after the grouping is compressed repetition;

Multi-group data after compression and the repetition is modulated back output.

Embodiments of the present invention also provide a kind of data rate control device, comprising: grouping module, compression replicated blocks and modulation module; Wherein,

Grouping module is used for will importing data according to the data rate of system requirements and is divided into more than one group;

The compression replicated blocks are used for every group of data are compressed repetition;

Modulation module is used for the data after the compression repetition are modulated.

From above as can be seen, a kind of method of rate control and device that embodiments of the present invention provide, under the situation of channel quality deterioration, these data are divided into groups and compressed repetition, and in conjunction with existing AMC modulation technique, reach the decrease speed of slowing down data rate, and keep the effect of relative higher data speed.

Description of drawings

Fig. 1 is the system architecture diagram of rate controlled of the present invention;

Fig. 2 is the implementation step flow chart of method of rate control of the present invention;

Fig. 3 is subscriber signal grouping and the waveform contrast schematic diagram that does not divide into groups in frequency domain in the specific embodiment of the invention;

Fig. 4 inserts the simulation curve figure of the method for rate control of (IFDMA, Interleaved FrequencyDivision Multiple Access) technology for the present invention is based on interlaced FDMA;

Fig. 5 is the system architecture diagram of rate controlled in a preferred embodiment of the present invention.

Embodiment

Thinking of the present invention is when the data rate of channel degradation or input system is excessive, will import data according to the data rate of system requirements and be divided into more than one group; Multi-group data after the grouping is compressed repetition; Multi-group data after compression and the repetition is modulated back output, thereby realize the decrease speed of actual data rate in the relieving system, keep the purpose of relative higher data speed simultaneously.

Below in conjunction with drawings and the specific embodiments the present invention is described in further detail again.

The apparatus structure block diagram of rate controlled as shown in Figure 1 in the embodiment of the invention.

This device comprises: data traffic control module 101, grouping module 102, compression replicated blocks 103, modulation module 104.

Data traffic control module 101 is used to control the data rate that enters after the current communication system.

Grouping module 102 is used for the input data are divided into many groups, the speed of every group of data after the grouping is reduced, to satisfy the data rate of system requirements.

Compression replicated blocks 103 are used for every group of data after grouping module 102 groupings are compressed repetition, make every group of data compressing after repeating satisfy the data rate of system requirements.

Modulation module 104 is used for every group of data after the 103 compression repetitions of compression replicated blocks are modulated, and the speed of every group of data after the modulation is different because the modulator approach that adopts is different, thereby satisfies the data rate of system requirements as much as possible.

Data traffic control module 101 is obtained the original user burst ... d ⁽³⁾d ⁽²⁾d ⁽¹⁾d ⁽⁰⁾, 102 pairs of these bursts of grouping module divide into groups, and obtain the subscriber signal sequence ... d ⁽³⁾d ⁽¹⁾With the subscriber signal sequence ... d ⁽²⁾d ⁽⁰⁾, respectively these two groups of subscriber signal sequences to be compressed and repetition by compression replicated blocks 103, the subscriber signal sequences after repeating by 104 pairs of compressions of modulation module are modulated.

Based on above-mentioned device, the concrete implementation step of the inventive method execution mode is proposed, specifically referring to shown in Figure 2:

Step 201 is obtained the original user burst that needs transmission.When system need reduce data rate, can reduce the flow of original user burst by the data traffic control module, thereby reduce the requirement that sub-carrier number satisfies system.

Step 202 is divided into groups to the original user burst according to the data rate of system requirements.

Suppose that the original user burst is [d ⁽⁰⁾, d ⁽¹⁾..., d ^(q-1)] ^T, in the corresponding diagram 1 ... d ⁽³⁾d ⁽²⁾d ⁽¹⁾d ⁽⁰⁾, the original user burst evenly is divided into two groups according to odd even:

Subscriber signal sequence 1:[d ⁽¹⁾, d ⁽³⁾..., d ^(q-1)] ^T, in the corresponding diagram 1 ... d ⁽³⁾d ⁽¹⁾

Subscriber signal sequence 2:[d ⁽⁰⁾, d ⁽²⁾..., d ^(q-2)] ^T, in the corresponding diagram 1 ... d ⁽²⁾d ⁽⁰⁾

If number of users is not an even number, mend 0 in the position, end of subscriber signal sequence 2.When system's current data speed is N times of the original speed of system, with the original user burst according to 0,1,2 ..., N evenly is divided into the N group, if number of users is not the integral multiple of N, mends 0 on the vacancy position of corresponding subscriber signal sequence.

Because the continuous variation of system channel deterioration condition, cause system data rates to require also to change thereupon, in order to satisfy the system data rates requirement that constantly changes, in taking into account system in other data rate control method, select suitable packet count, the original user burst is divided into many groups.

Step 203 is compressed repetition respectively to subscriber signal sequence 1 and subscriber signal sequence 2, and the coefficient of selecting compression to repeat according to system requirements is 2, and compression obtains family burst C after repeating ₁And C ₂Wherein,

${\mathrm{<figure-callout\; id="1"\; label="C"\; filenames="A20061016877400091.png,A20061016877400131.png"\; state="\{\{state\}\}">C</figure-callout>}}_1=\frac{1}{2}{[{d_0}^{\left(1\right)},{d_0}^{\left(3\right)},...,{d_1}^{\left(1\right)},{d_1}^{\left(3\right)},...,{d_{Q-1}}^{\left(1\right)},{d_{Q-1}}^{\left(3\right)},{d_0}^{\left(1\right)},{d_0}^{\left(3\right)},...,{d_1}^{\left(1\right)},{d_1}^{\left(3\right)},...,{d_{Q-1}}^{\left(1\right)},{d_{Q-1}}^{\left(3\right)}]}^T$

${\mathrm{<figure-callout\; id="2"\; label="C"\; filenames="A20061016877400091.png,A20061016877400131.png"\; state="\{\{state\}\}">C</figure-callout>}}_2=\frac{1}{2}{[{d_0}^{\left(0\right)},{d_0}^{\left(2\right)},...,{d_1}^{\left(0\right)},{d_1}^{\left(2\right)},...,{d_{Q-1}}^{\left(0\right)},{d_{Q-1}}^{\left(2\right)},{d_0}^{(10},{d_0}^{\left(2\right)},...,{d_1}^{\left(0\right)},{d_1}^{\left(2\right)},...,{d_{Q-1}}^{\left(0\right)},{d_{Q-1}}^{\left(2\right)}]}^T$

Fig. 3 is divided into two groups subscriber signal sequence and the contrast schematic diagram of subscriber signal sequence on frequency domain that adopts the IFDMA technology but be not grouped for adopting the present invention.Be the frequency oscillogram of subscriber signal sequence before compression repeats more than the broad arrow among the figure, indicate user 1, user 2, user 3 and user 4 respectively in the abscissa arrow upper end of each frequency oscillogram.It among the figure frequency oscillogram after according to IFDMA technology and the inventive method the original user burst being handled.As can be seen from the figure, the spacing between each the subscriber signal sequence subcarrier under the IFDMA technology of the gap ratio between each the subscriber signal sequence subcarrier after the original user burst grouping being divided into groups according to the inventive method obviously increases.

Thereby as can be seen, compare by the scheme that changes modulation system with independent in the prior art, present embodiment adopts packet mode, reduced the data transfer rate on each channel, when channel degradation, need not to change modulation system, just can satisfy channel after the deterioration, channel degradation is reduced to minimum to the influence of system the requirement of system's speed; And, can also alleviate the interference between adjacent sub-carrier because the spacing between subcarrier increases.

Step 204 adopts the AMC technology to compressing the subscriber signal sequence C that obtains after the repetition ₁With the subscriber signal sequence C ₂Carry out selective modulation, obtain X ₁And X ₂

The AMC modulation technique that modulated process of the present invention is selected for use comprises the change chnnel coding and changes two kinds of technology of modulation system.When if the change chnnel coding can't satisfy the error rate of system requirements, then adopt to change modulation system, modulator approach comprises 64QAM, 16QAM, QPSK, PSK etc.

Fig. 4 is the simulation curve figure that the present invention is based on the method for rate control of IFDMA technology.Ordinate is the traffic among the figure, and unit is a percentage, and the traffic is represented the ratio of actual data rate and system's maximum data rate in the system; Abscissa is a signal to noise ratio, and unit is a decibel; Heavy line is based on data rate decline curve of the present invention, and fine line is the data rate decline curve based on existing AMC technology.

Data rate when system adopts the 64QAM modulation system and do not pass through the method for adjusting subcarrier spacing is 100%.Along with number of sub carrier wave reduces, such as dropping to 10 from 11, maximum user's sub-carrier number is 16, and data rate drops to 62.50% from 68.75%.If but at this moment modulation system is reduced to 16QAM, and maximum user's sub-carrier number still is 16 simultaneously, then system data rates is reduced to 66.67% of initial rate.Because 66.67% greater than 62.50%, so in this case, for satisfying corresponding quality of service requirement (QoS, Quality of Service) demand, keep relative higher data speed simultaneously, can select to reduce modulation levels, and not select to reduce the data rate control method of sub-carrier number.

As can be seen, do not having under the situation of chnnel coding from simulation curve figure, the present invention will change modulation levels and the change sub-carrier number combines, and makes the data rate decrease speed become milder.

Below be the present invention according to the different method of rate control that situation adopted:

In the data rate control system based on the IFDMA technology, setting a sub-carrier frequencies bandwidth is f _b, be spaced apart Δ f between the adjacent sub-carrier centre frequency, data speed is not being carried out under the situation of any adjustment Δ f=f _b, at this moment, the maximum data transfer rate of system's support is R.

Situation 1: the data rate of sending into the data traffic control module is identical with the maximum data rate that system supports, but because the requirement of number of transmit antennas in the system, need divide into groups to data, suppose to be divided into 2 groups, then every group of data rate after the grouping becomes 1/2 of former data rate, the frequency difference Δ f=2f between the adjacent sub-carrier of every group of data _b

For the frequency difference Δ f=f between the adjacent sub-carrier that makes every group of data after the grouping _b, can repeat 2 times to every group of data compression by the compression replicated blocks and realize.

Situation 2: the data rate of input traffic amount control module be the maximum data rate supported of system n doubly.

In order to satisfy the maximum data transfer rate requirement that system supports, fetched data is divided into the n group, thereby makes every group of data rate after the grouping be reduced to the maximum data rate that system supports.

Situation 3: when the channel quality deterioration, need to adjust data rate, satisfy system QoS by strengthening subcarrier spacing.

In situation 3, can in time domain, reduce former data rate by the data traffic control module and satisfy system requirements.Be specially, the data traffic control module reduces the flow of data, and Q data symbol of input reduced to and imported Q-1 data symbol in original certain hour, makes that the interval between the adjacent sub-carrier centre frequency becomes $\mathrm{\&Delta;}{f}^{\&prime;}=\frac{Q}{Q-1}{f}_b,$ Δ f ' is bigger than former Δ f

Therefore can be used to reduce the interference between adjacent sub-carrier with this band frequency at interval at interval, improve the stability of system as protection.In addition, Ci Shi message transmission rate also is enhanced

According to above three kinds of situations, another preferred embodiment of the present invention is proposed, referring to shown in Figure 5:

Device shown in Figure 5 is a kind of device of automatic realization data rate control.This device is to increase detection module 501 and data rate control module 502 on the basis of device shown in Figure 1.

Detection module 501 is used to detect the requirement of whether satisfying system data rates through the data rate after data traffic control module 101, grouping module 102, compression replicated blocks 103, modulation module 104 changes, if do not satisfy, detection module 501 feeds back to data rate control module 502 with transmission; Otherwise detection module 501 is failure to actuate.

Data rate control module 502 is according to detection module 501 feedacks, respectively data flow-control module 101, grouping module 102, compression replicated blocks 103, modulation module 104 are controlled, the actual speed rate of data in the Adjustment System is to satisfy the data rate of system requirements.

The above only is preferred embodiment of the present invention, and is in order to restriction the present invention, within the spirit and principles in the present invention not all, any modification of being done, is equal to replacement, improvement etc., all should be included within protection scope of the present invention.

Claims (9)

1. a data rate control method is characterized in that, comprising:

To import data according to the data rate of system requirements and be divided into more than one group;

Multi-group data after the grouping is compressed repetition;

Multi-group data after compression and the repetition is modulated back output.

2. method according to claim 1 is characterized in that, describedly will import data to be divided into the data symbol number that every group of data obtaining after more than one group comprise identical.

3. method according to claim 1 is characterized in that, described data rate according to system requirements will be imported data and be divided into and further comprising before more than one group: according to the data rate of system requirements, adjust the flow of input data.

4. method according to claim 3 is characterized in that, the flow of described adjustment input data is: the number that changes input data symbol in the unit interval.

5. method according to claim 1 is characterized in that, described multi-group data after the grouping is compressed and repeat further to comprise: according to input data institute packet count, select compression and the coefficient that repeats.

6. a data rate control device is characterized in that, comprising: grouping module, compression replicated blocks and modulation module; Wherein,

Grouping module is used for will importing data according to the data rate of system requirements and is divided into more than one group;

The compression replicated blocks are used for every group of data are compressed repetition;

Modulation module is used for the data after the compression repetition are modulated.

7. device according to claim 6 is characterized in that described device further comprises the data traffic control module, and this module is used for the flow according to the data rate adjustment input data of system requirements.

8. device according to claim 6 is characterized in that, described compression replicated blocks select the compression repeat factor to compress repetition according to input data institute packet count.

9. device according to claim 6 is characterized in that, this device further comprises:

Detection module, whether the actual data rate that is used for detection system satisfies the data rate of system requirements; If do not satisfy, detection module feeds back to the data rate control module with transmission; Otherwise detection module is failure to actuate;

The data rate control module is used for according to control the data flows the respectively actual data rate of control module, grouping module, compression replicated blocks and modulation module Adjustment System of detection module feedack.

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