The method that shift sequence in the tdd systems under public distributing mode detects
Technical field
The present invention relates to the method that shift sequence in a kind of TD-SCDMA (TD SDMA) communication system detects, specifically, relate to a kind ofly in the TD-SCDMA communication system, under public distributing mode, detect the method for shift sequence fast and accurately.
Background technology
In the receiving system of TD-SCDMA system, the method for salary distribution of shift sequence is stipulated by system in the whole system.Setting according to network layer, the method of salary distribution of the training sequence of system has three kinds, as shown in Figure 1: default distributing mode (DEFAULT), public distributing mode (COMMON) and assigned distributing mode by user (UESPECFIC), in three kinds of different shift sequence methods of salary distribution, the available Given information of system also is different, so follow-up detection algorithm also will change according to different Given informations.
Transfer training information has great influence to the demodulation performance of whole system.System distributes to one or more movement training sequence of user according to service needed, information corresponding to these professional transmission requirements, the base station can send a configuration information, by these configuration informations of decoding, the terminal use can be definite the information that calculates professional employed movement training sequence, but will be transmitted in these configuration informations first radio frames in a transmission intercal, can't obtain definite information before obtaining in that this configuration information is decoded, therefore at least in first radio frames of certain Transmission Time Interval, the targeted customer needs the situation of the movement training sequence of the activation that base stations detected sends, these information are in the process of the demodulation of back, all be essential, and the situation of the detection of movement training sequence is very serious to the influence of follow-up demodulation, in the time of the effective movement training sequence of omission, can cause the situation of directly losing of data, can cause the severe exacerbation of follow-up decoder module performance, also be the mis-behave of joint-detection module simultaneously, same when the flase drop situation occurring, also can make the mis-behave of follow-up joint-detection, cause the waste of system's calculation resources simultaneously.
Particularly when the targeted customer is assigned with a plurality of physical coded combination transfers information, the movement training sequence of how judging the targeted customer accurately and being distributed, be whole receiving system most important content, its performance will produce great influence to receiving the demodulating system performance.Conventional detection algorithm is to the use and the imperfection of targeted customer's Given information, and therefore the information of the transfer training system of detection system need effectively to utilize all possible information that this moment, system assignment was given the targeted customer accurately.
Summary of the invention
The object of the present invention is to provide the method that the shift sequence under public distributing mode detects in a kind of tdd systems, the information of the physical layer encodes combination of transmitted channel by utilizing this user fully, detect the information of the activated training sequence of distributing to this user accurately, and the while is according to the information of this user's training sequence, calculate the information of other users' activated training sequence, to detect other users' information accurately, help the realization of the joint detection algorithm of receiving system.
For reaching above-mentioned purpose, the invention provides the method that the shift sequence under public distributing mode detects in a kind of tdd systems, it comprises following steps:
Step 1, the effectively search of estimating window obtain power maximum and the pairing number of this power maximum in whole channel estimation windows;
Step 2, calculating average noise and noise gate;
Step 3, carry out the detection of discontinuous transmission: when system configuration is the state of discontinuous transmission, need carry out the state-detection of discontinuous transmission; When system configuration is not used discontinuous transmission state, direct redirect execution in step 4;
The t value is promptly exported in step 4, the effective estimating window of output position.
In the described step 1, can directly search the power maximum and the pairing number of this power maximum that obtain in whole channel estimation windows, that is:
And record P
MaxThe window number t of pairing movement training sequence.
In the described step 1, the power that the power maximum in whole channel estimation windows and the pairing number of this power maximum also can be by each possible movement training sequence estimating windows relatively and maximum obtain, that is:
Record P
Max SumThe estimating window number t of pairing movement training sequence; Obtain the power maximum in this t estimating window simultaneously:
In the described step 1, the active path power that the power maximum in whole channel estimation windows and the pairing number of this power maximum also can be by the possible positions of each possible movement training sequence estimating window relatively and maximum obtain, that is:
Wherein, the position that NoiseMask (k) has write down noise, wherein { 1,0} when NoiseMask (k) is 1, is expressed as noise to NoiseMask (k) ∈; When NoiseMask (k) is 0, the expression active path;
Record P
Max SumThe estimating window number t of pairing movement training sequence; Obtain the power maximum in this t estimating window simultaneously
Described step 2 comprises following steps:
The average noise P of step 2.1, computing system
Noise
The thresholding Thr of step 2.2, the discontinuous reception of calculating
DTX: Thr
DTX=P
Noise* K
DTX, wherein, K
DTXBe predefined thresholding, it can obtain by field test and method of emulation.
In the described step 2.1, the positional information of the noise that can calculate according to previous frame is calculated the average noise P of system in this frame
Noise:
Wherein: NoiseMask represents the position quantity of the noise in the previous frame, and this value is upgraded in this frame, by being used in the next frame.
In the described step 2.1, the mean value calculation of noise power that also can be by calculating the remaining movement training sequence estimating window except t obtains P
Noise:
Wherein: H represents other the set of movement training sequence estimating window except t.
Further, in order to save calculation resources, in the described step 2.1, the transposition of partial training sequence estimating window that can choose among the H calculates P
Noise
In the step 3, the state-detection of described discontinuous transmission comprises following steps:
The maximum P of t the estimating window that calculates in step 3.1, the determining step 1
MaxWhether be not less than the thresholding Thr of the discontinuous reception that calculates in the step 2.2
DTX:
If P
Max〉=Thr
DTX, think that then this moment, there was effective received signal in this time slot, redirect execution in step 4:
Otherwise thinking does not have received signal arrival effectively in this channel, and this moment, active was closed in the follow-up operation of this channel.
The method that shift sequence in a kind of tdd systems provided by the invention under public distributing mode detects, the information of the physical layer encodes combination of transmitted channel by utilizing this user fully, detect the information of the activated training sequence of distributing to this user accurately, and the while is according to the information of this user's training sequence, calculate the information of other users' activated training sequence, to detect other users' information accurately, help the realization of the joint detection algorithm of receiving system.
Description of drawings
Fig. 1 is the allocation model of the training sequence in the background technology TDS-CDMA system;
Fig. 2 is the flow chart of the shift sequence detecting method under public distributing mode in the tdd systems provided by the invention.
Embodiment
Below, introduce specific embodiments of the invention in detail, so that further understand content of the present invention by Fig. 2.
As shown in Figure 2, the invention provides the method that the shift sequence under public distributing mode detects in a kind of tdd systems, it comprises following steps:
Step 1, the effectively search of estimating window obtain power maximum and the pairing number of this power maximum in whole channel estimation windows;
Step 2, calculating average noise and noise gate;
Step 3, carry out the detection of discontinuous transmission: when system configuration is the state of discontinuous transmission, need carry out the state-detection of discontinuous transmission; When system configuration is not used discontinuous transmission state, direct redirect execution in step 4;
The t value is promptly exported in step 4, the effective estimating window of output position.
In the described step 1, can directly search the power maximum and the pairing number of this power maximum that obtain in whole channel estimation windows, that is:
And record P
MaxThe window number t of pairing movement training sequence.
In the described step 1, the power that the power maximum in whole channel estimation windows and the pairing number of this power maximum also can be by each possible movement training sequence estimating windows relatively and maximum obtain, that is:
Record P
Max SumThe estimating window number t of pairing movement training sequence; Obtain the power maximum in this t estimating window simultaneously:
In the described step 1, the active path power that the power maximum in whole channel estimation windows and the pairing number of this power maximum also can be by the possible positions of each possible movement training sequence estimating window relatively and maximum obtain, that is:
Wherein, the position that NoiseMask (k) has write down noise, wherein { 1,0} when NoiseMask (k) is 1, is expressed as noise to NoiseMask (k) ∈; When NoiseMask (k) is 0, the expression active path;
Record P
Max SumThe estimating window number t of pairing movement training sequence; Obtain the power maximum in this t estimating window simultaneously
Described step 2 comprises following steps:
The average noise P of step 2.1, computing system
Noise
The thresholding Thr of step 2.2, the discontinuous reception of calculating
DTX: Thr
DTX=P
Noise* K
DTX, wherein, K
DTXBe predefined thresholding, it can obtain by field test and method of emulation.
In the described step 2.1, the positional information of the noise that can calculate according to previous frame is calculated the average noise P of system in this frame
Noise:
Wherein: NoiseMask represents the position quantity of the noise in the previous frame, and this value is upgraded in this frame, by being used in the next frame.
In the described step 2.1, the mean value calculation of noise power that also can be by calculating the remaining movement training sequence estimating window except t obtains P
Noise:
Wherein: H represents other the set of movement training sequence estimating window except t.
Further, in order to save calculation resources, in the described step 2.1, the transposition of partial training sequence estimating window that can choose among the H calculates P
Noise
In the step 3, the state-detection of described discontinuous transmission comprises following steps:
The maximum P of t the estimating window that calculates in step 3.1, the determining step 1
MaxWhether be not less than the thresholding Thr of the discontinuous reception that calculates in the step 2.2
DTX:
If P
Max〉=Thr
DTX, think that then this moment, there was effective received signal in this time slot, redirect execution in step 4;
Otherwise thinking does not have received signal arrival effectively in this channel, and this moment, active was closed in the follow-up operation of this channel.
Shift sequence detecting method in a kind of tdd systems provided by the invention under public distributing mode, the information of the physical layer encodes combination of transmitted channel by utilizing this user fully, detect the information of the activated training sequence of distributing to this user accurately, and the while is according to the information of this user's training sequence, calculate the information of other users' activated training sequence, to detect other users' information accurately, help the realization of the joint detection algorithm of receiving system.