CN1933361A - Up inserting detection method - Google Patents

Abstract

The present invention discloses a method for uplink access detection. The method includes: a. performing shaping filtering and sampling on the received data of the current subframe located in the detection window of all receiving antennas to obtain the data of the current subframe of each receiving antenna; Detecting the data vector; b. weighting the detection data vector of the current subframe of each receiving antenna according to the estimation of the interference power envelope in the detection window on each receiving antenna; c. weighting the weighted detection data corresponding to each receiving antenna Correlation operation is performed on the vector and the detected signature sequence; and multi-antenna combination is performed on the obtained correlation operation results of all receiving antennas, and the signature sequence identification is performed on the combination result. Applying the method of the present invention, the interference has been suppressed in the weighted detection data vector, so the influence of the interference is also suppressed in the detection results after performing correlation calculation and multi-antenna combination and signature sequence identification, greatly improving the uplink connection. into detection performance.

Description

A method for uplink access detection

technical field

The invention relates to an access detection technology, in particular to an uplink access detection method in a Time Division Synchronous Code Division Multiple Access (TD-SCDMA) system.

Background technique

TD-SCDMA system is a time-division synchronous CDMA system. In this system, strict uplink synchronization is realized through software and frame structure design. The frame structure of TD-SCDMA system has four layers: super frame, wireless frame, sub frame and time slot/code. Wherein, a superframe is 720 ms long and consists of 72 radio frames, each radio frame is 10 ms long and includes two 5 ms subframes. The specific subframe structure is shown in Figure 1. A 5ms subframe consists of 3 special time slots and 7 regular time slots. The 3 special time slots are the downlink pilot time slot (DwPTS) lasting 96 chips (chip), the uplink pilot time slot (UpPTS) lasting 160 chips, and the guard interval (GP) lasting 96 chips; 7 regular time slots , each regular slot lasts 864chips.

In the design of the frame structure, DwPTS is designed for downlink pilot and synchronization, and is used to transmit the pilot signal of the wireless base station (NodeB), that is, the downlink synchronization signal; UpPTS is designed for uplink pilot and synchronization , which is used to transmit the pilot signal of the user terminal (UE) for uplink synchronization; GP is the guard interval, which is used to avoid the interference of the downlink pilot signal sent by the NodeB in the DwPTS to the uplink received UpPTS.

Ideally, the system expects the uplink pilot signal sent by the UE to be received by the NodeB during the period composed of GP and UpPTS; and considers that the received uplink pilot signal will not be interfered by itself and the adjacent NodeB downlink pilot signal. However, in actual situations, the uplink pilot signal received by the NodeB is likely to be interfered by itself and the downlink pilot signal of the adjacent NodeB. The current uplink access detection process ignores the existence of this interference, thus deteriorating the access performance of the TD-SCDMA system, especially when there is strong interference, the access performance is severely degraded.

Fig. 2 is a specific flow chart of the uplink access detection method in the current TD-SCDMA system. As shown in Figure 2, the method includes:

Step 201, all receiving antennas receive data within the detection window, and use the shaping filter to filter the received data for the data received by each receiving antenna, and sample according to the chip rate, and extract 256 complex data corresponding to GP and UpPTS, That is, it constitutes the detection data vector of the receiving antenna.

In the current uplink access detection algorithm, the detection window is defined as the GP+UpPTS period. In this step, the obtained detection data vectors include 256 detection data corresponding to each chip time in the detection window. At some chip times, there may be interference from uplink pilot signals, so that the detection data corresponding to these chip times contains some interference signal components.

In step 202, a correlation operation is performed between the detected data vector of each receiving antenna and the detected signature sequence, namely SYNC_UL.

Step 203, performing multi-antenna combination on the correlation results obtained by all receiving antennas.

In step 204, the result of combining multiple antennas is identified through a signature sequence identification algorithm to obtain an uplink access detection result.

So far, the process of uplink access detection ends.

It can be seen from the above process that in the current uplink access detection algorithm, the detection data vector obtained after shaping filtering and sampling in step 201 is directly used for correlation calculation with the signature sequence and subsequent multi-antenna combination and signature sequence recognition. Under this process, when the GP+UpPTS period of the system is strongly interfered, that is, some chips in the detection window are subject to strong interference, the detection data vector obtained after shaping filtering and sampling is the same as these The detection data corresponding to the interference chip time also contains strong interference signal components, and the uplink access detection results obtained after using such detection data vectors for subsequent correlation calculations, multi-antenna combination, and signature sequence identification are also Strong interference is introduced, which deteriorates the uplink access detection performance and seriously affects the access performance of the system.

Contents of the invention

In view of this, the present invention provides a method for uplink access detection, which can realize uplink access detection resisting the interference of downlink pilot signals, and improve the uplink access detection performance of the system.

To achieve the above object, the present invention adopts the following technical solutions:

A method for uplink access detection, comprising:

a. Perform shaping filtering and sampling on the received data of the current subframe located in the detection window of all receiving antennas to obtain the detected data vector of the current subframe of each receiving antenna;

b. Weighting the detection data vectors of the current subframe of each receiving antenna according to the estimation of the interference power envelope in the detection window on each receiving antenna;

c. Correlating the weighted detection data vector corresponding to each receiving antenna with the detected signature sequence; performing multi-antenna combination on the obtained correlation calculation results of all receiving antennas, and performing signature sequence identification on the combined result.

Preferably, the detection window in step a may be any time period during which uplink pilot signals may be received.

Preferably, the arbitrary time period during which the uplink pilot signal may be received may be: a time period consisting of a guard interval and an uplink pilot time slot, or a time period consisting of a guard interval, an uplink pilot time slot and an immediately following uplink pilot time slot. The time period formed by the first regular time slot after the frequency time slot.

Preferably, the interference power envelope estimation in step b may be the interference power envelope estimation of the current subframe or the interference power envelope estimation of the previous subframe of the current subframe.

Preferably, when the interference power envelope estimation is the interference power envelope estimation of the current subframe, the estimation based on the interference power envelope within the detection window on the receiving antenna can be performed after step a.

Preferably, when the interference power envelope estimate is the interference power envelope estimate of the previous subframe of the current subframe, the estimation of the interference power envelope in the detection window on the receiving antenna can be performed before step a conduct.

Preferably, step b may further include: estimating the interference power envelope of the current subframe within the detection window, and storing the estimation result for estimation of the interference power envelope of the next subframe within the detection window.

Preferably, the estimation of the interference power envelope in the detection window on each receiving antenna described in step b can be:

${\mathrm{<span\; class="notranslate">\; P</span>}}_{\mathrm{<span\; class="notranslate">\; N</span>}<span\; class="notranslate">\; \&times;</span>\mathrm{<span\; class="notranslate">\; 1</span>}}^{\mathrm{<span\; class="notranslate">\; k</span>}}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; t</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; =</span>{\mathrm{<span\; class="notranslate">\; the\; y</span>}}^{<span\; class="notranslate">\; *</span>}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; t</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; .</span><span\; class="notranslate">\; \&times;</span>\mathrm{<span\; class="notranslate">\; the\; y</span>}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; t</span>}<span\; class="notranslate">\; )</span>$

P ^k (t) = βP ^k (t) + (1-β) P ^k (t-1)

Among them, t is the subframe number for estimation of the interference power envelope in the detection window, k is the index of the receiving antenna, Pk(t) is the interference power envelope estimate in the t subframe detection window of the kth receiving antenna, y(t) is the detection data vector of t subframe, (.×) means that the elements of the vector are multiplied correspondingly to get A new vector, * means conjugate operation; β is a positive real number less than or equal to 1.

Preferably, the threshold is preset, and the weighting of the detection data vectors of the current subframe of each receiving antenna in step b can be:

Compare the estimated value of the interference power at each chip time in the detection window with the preset threshold, if the estimated value of the interference power at a certain chip time is greater than the preset threshold, the detection data vector corresponding to the chip time The weighted value of the detected data is set to 0, and if the estimated value of interference power at a certain chip time is less than or equal to the preset threshold, non-zero weighting is performed on the detected data corresponding to the chip time in the detected data vector.

Preferably, the non-zero weighting of the detection data corresponding to the chip moment in the detection data vector may be: $w^k\left(\mathrm{no}\right)={\left({\stackrel{\&OverBar;}{P}}_t^k\right)}^{-\frac{1}{2}},$ Among them, t is the subframe number of the interference power envelope estimation in the detection window, n is the chip time index value, w ^k (n) is the detection data corresponding to the nth chip time in the detection data vector The weighting coefficient, P _t ^k (n) is the estimated value of the interference power corresponding to the nth chip moment in the detection window.

It can be seen from the above technical solution that in the uplink access detection method of the present invention, the detection data vector obtained through shaping filtering and sampling is weighted by the estimation of the interference power envelope in the detection window, so as to suppress the interference existing in the detection data vector ; Then use the weighted detection data vector to perform subsequent correlation calculation, multi-antenna combination and signature sequence identification, so as to obtain the uplink access detection result. Since the interference has been suppressed in the weighted detection data vector, the influence of interference is also suppressed in the detection results after correlation calculation, multi-antenna combination and signature sequence identification, which greatly improves the uplink access detection performance, thereby improving detection performance of the entire system.

Description of drawings

Fig. 1 is the subframe structure of TD-SCDMA system.

Fig. 2 is a specific flowchart of uplink access detection in the current TD-SCDMA system.

Fig. 3 is an overall flow chart of the uplink access detection method in the present invention.

Fig. 4 is a specific flow chart of the uplink access detection method in the embodiment of the present invention.

FIG. 5 is a comparison diagram of access performance for uplink access detection using the methods shown in FIG. 4 and FIG. 2 .

Detailed ways

In order to make the object, technical solution and advantages of the present invention clearer, the specific implementation manners of the present invention will be described below with reference to the accompanying drawings and examples.

The basic idea of the present invention is to estimate the interference power envelope for the detection data obtained through shaping filtering and sampling, and use the estimation of the interference power envelope in the detection window to carry out weighting to suppress the interference existing in the detection data vector; The weighted detection data vector is used to perform subsequent correlation calculation, multi-antenna combination and signature sequence identification, so as to obtain the uplink access detection result.

Fig. 3 is an overall flow chart of the uplink access detection method in the present invention. As shown in Figure 3, the method includes:

Step 301, performing shaping filtering and sampling on the received data of the current subframe within the detection window of all receiving antennas to obtain the detected data vectors of the current subframe of each receiving antenna;

Step 302, weighting the detection data vector of the current subframe according to the estimation of the interference power envelope in the detection window on the receiving antenna;

Step 303 , correlating the weighted detection data vector corresponding to each receiving antenna with the detected signature sequence; performing multi-antenna combination on the obtained correlation calculation results of all receiving antennas, and identifying the signature sequence on the combined result.

The above is a general overview of the uplink access detection method in the present invention. The present invention is described in further detail below in conjunction with embodiment.

In the embodiment of the present invention, the definition of the uplink access detection window may not be limited to the period of 256 chips of GP+UpPTS, but may be extended to any time period when the NodeB may receive the uplink pilot signal, such as GP+UpPTS +TS1 period, wherein the TS1 time slot is a regular time slot immediately following the UpPTS time slot in the subframe structure.

In step 302 described above in FIG. 3 , the estimation of the interference power envelope used when weighting the detected data vector may be the estimation of the interference power envelope of the subframe currently performing uplink access detection, or the estimation of the interference power envelope of Estimation of the interference power envelope of the subframe preceding the subframe in which the uplink access detection is currently performed. The following embodiments are implemented by estimating the interference power envelope of the current subframe.

The uplink access detection is a random access detection process, which is performed every few subframes. For a certain uplink access detection process, the subframe used for uplink access detection is called the current subframe.

Fig. 4 is a specific flow chart of the uplink access detection method in the embodiment of the present invention. As shown in Figure 4, the method includes:

Step 401 , each receiving antenna receives data of the current subframe within the detection window, uses a shaping filter to filter the received data, samples at a chip rate, and extracts a detection data vector.

The method for extracting the detection data vector in this step is the same as the existing uplink access detection method shown in FIG. 2 . Assuming that uplink access detection is performed in t subframe, then t subframe is the current subframe, and the obtained detection data vector is expressed as follows:

${\mathrm{<span\; class="notranslate">\; the\; y</span>}}_{\mathrm{<span\; class="notranslate">\; N</span>}<span\; class="notranslate">\; \&times;</span>\mathrm{<span\; class="notranslate">\; 1</span>}}^{\mathrm{<span\; class="notranslate">\; k</span>}}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; t</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; =</span>{\left[\begin{array}{cccc}{\mathrm{<span\; class="notranslate">\; the\; y</span>}}_{\mathrm{<span\; class="notranslate">\; t</span>}}^{\mathrm{<span\; class="notranslate">\; k</span>}}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; )</span>& {\mathrm{<span\; class="notranslate">\; the\; y</span>}}_{\mathrm{<span\; class="notranslate">\; t</span>}}^{\mathrm{<span\; class="notranslate">\; k</span>}}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 2</span>}<span\; class="notranslate">\; )</span>& <span\; class="notranslate">\; .</span><span\; class="notranslate">\; .</span><span\; class="notranslate">\; .</span>& {\mathrm{<span\; class="notranslate">\; the\; y</span>}}_{\mathrm{<span\; class="notranslate">\; t</span>}}^{\mathrm{<span\; class="notranslate">\; k</span>}}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; N</span>}<span\; class="notranslate">\; )</span>\end{array}\right]}^{\mathrm{<span\; class="notranslate">\; T</span>}}<span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; )</span>$

Among them, k is the index of the receiving antenna, y _N×1 ^k (t) is the detection data vector on the kth receiving antenna in the t subframe, y _t ^k (n) is the detection data vector of the kth receiving antenna in the detection window The detection data at k chip time, N is the length of the detection window.

Step 402, according to the detected data vector on each receiving antenna, estimate the interference power envelope of the current subframe in the detection window on the antenna.

Corresponding to the kth antenna, the method of estimating the interference power envelope according to the detection data can be:

${\mathrm{<span\; class="notranslate">\; P</span>}}_{\mathrm{<span\; class="notranslate">\; N</span>}<span\; class="notranslate">\; \&times;</span>\mathrm{<span\; class="notranslate">\; 1</span>}}^{\mathrm{<span\; class="notranslate">\; k</span>}}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; t</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; =</span>{\left[\begin{array}{cccc}{\mathrm{<span\; class="notranslate">\; p</span>}}_{\mathrm{<span\; class="notranslate">\; t</span>}}^{\mathrm{<span\; class="notranslate">\; k</span>}}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; )</span>& {\mathrm{<span\; class="notranslate">\; p</span>}}_{\mathrm{<span\; class="notranslate">\; t</span>}}^{\mathrm{<span\; class="notranslate">\; k</span>}}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 2</span>}<span\; class="notranslate">\; )</span>& <span\; class="notranslate">\; .</span><span\; class="notranslate">\; .</span><span\; class="notranslate">\; .</span>& {\mathrm{<span\; class="notranslate">\; p</span>}}_{\mathrm{<span\; class="notranslate">\; t</span>}}^{\mathrm{<span\; class="notranslate">\; k</span>}}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; N</span>}<span\; class="notranslate">\; )</span>\end{array}\right]}^{\mathrm{<span\; class="notranslate">\; T</span>}}$

${<span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; the\; y</span>}}^{<span\; class="notranslate">\; *</span>}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; t</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; .</span><span\; class="notranslate">\; \&times;</span>\mathrm{<span\; class="notranslate">\; the\; y</span>}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; t</span>}<span\; class="notranslate">\; )</span>$

${\stackrel{<span\; class="notranslate">\; \&OverBar;</span>}{\mathrm{<span\; class="notranslate">\; P</span>}}}^{\mathrm{<span\; class="notranslate">\; k</span>}}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; t</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; =</span>{\left[\begin{array}{cccc}{\stackrel{<span\; class="notranslate">\; \&OverBar;</span>}{\mathrm{<span\; class="notranslate">\; p</span>}}}_{\mathrm{<span\; class="notranslate">\; t</span>}}^{\mathrm{<span\; class="notranslate">\; k</span>}}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; )</span>& {\stackrel{<span\; class="notranslate">\; \&OverBar;</span>}{\mathrm{<span\; class="notranslate">\; p</span>}}}_{\mathrm{<span\; class="notranslate">\; t</span>}}^{\mathrm{<span\; class="notranslate">\; k</span>}}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 2</span>}<span\; class="notranslate">\; )</span>& <span\; class="notranslate">\; .</span><span\; class="notranslate">\; .</span><span\; class="notranslate">\; .</span>& {\stackrel{<span\; class="notranslate">\; \&OverBar;</span>}{\mathrm{<span\; class="notranslate">\; p</span>}}}_{\mathrm{<span\; class="notranslate">\; t</span>}}^{\mathrm{<span\; class="notranslate">\; k</span>}}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; N</span>}<span\; class="notranslate">\; )</span>\end{array}\right]}^{\mathrm{<span\; class="notranslate">\; T</span>}}$

$<span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; \&beta;</span>}{\mathrm{<span\; class="notranslate">\; P</span>}}^{\mathrm{<span\; class="notranslate">\; k</span>}}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; t</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; +</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; \&beta;</span>}<span\; class="notranslate">\; )</span>{\stackrel{<span\; class="notranslate">\; \&OverBar;</span>}{\mathrm{<span\; class="notranslate">\; P</span>}}}^{\mathrm{<span\; class="notranslate">\; k</span>}}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; t</span>}<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 2</span>}<span\; class="notranslate">\; )</span>$

Among them, P ^k (t) is the interference power envelope estimation of the kth receiving antenna, p _t ^k (n) is the interference power envelope estimation value corresponding to the nth chip time in the detection window, (.×) means Multiply the elements of the vector correspondingly to get a new vector, * indicates the conjugate operation; β is a positive real number less than or equal to 1, called the forgetting factor, which indicates that when the uplink access detection is performed in the t subframe, the previous The degree of influence of the interference power envelope estimation of the subframe on the interference power envelope estimation of the subframe. When t=1, that is, when an uplink access detection is performed on a user terminal for the first time, P ^k (1)=βP ^k (1).

It can be seen from formula (2) that for a subframe t, its interference power envelope estimation is related to the interference power envelope estimation of other subframes before this subframe. Therefore, in this embodiment, for a subframe for which no uplink access detection is performed, interference power envelope estimation for the subframe still needs to be performed. Every time a subframe is received, regardless of whether uplink access detection is performed in the subframe, the interference power envelope of the subframe must be estimated, that is, the interference power envelope estimation result is updated once, and recorded The estimation result this time is used for the estimation of the interference power envelope next time.

Step 403, according to the interference power envelope estimation result of each receiving antenna obtained in step 402, weight the detection data vector of each receiving antenna to suppress interference.

In this embodiment, all receiving antennas are weighted in the same manner, and the kth receiving antenna is taken as an example to illustrate the specific weighting manner.

For the detected data vector obtained in step 401, when some chip moments are strongly interfered, the estimated value p _t ^k (n) of the interference power envelope corresponding to these chip moments will be more prominent. In the interference power envelope estimation result, the estimated value of this type of interference power envelope can be distinguished, and the corresponding chip time can be found, so that the detection data corresponding to the chip time can be shielded to avoid its participation in the subsequent Correlation operations and other operations to suppress the interference at these chip moments.

The specific way to distinguish the interfered chip time can be as follows: set a threshold in advance, compare the interference power value at each chip time in the detection window with the preset threshold, when the interference power value at a certain chip time When it is greater than the preset threshold, it indicates that the chip time is subject to strong interference, and the detection data corresponding to the chip time needs to be cleared in the detection data vector, so the detection data corresponding to the chip time is set to zero, so that Eliminate the influence of interference; when the interference power value of a certain chip time is less than or equal to the preset threshold, it indicates that the chip time is not subject to strong interference, and the detection data value of the chip time can be kept unchanged or according to the The interference power value at the chip moment performs non-zero weighting on the detection data.

In this embodiment, the interference power value at each chip time of the current t subframe within the detection window is compared with a preset threshold, so as to weight the detection data vector of the t subframe. More specifically, the following formula can be used for weighting:

${\mathrm{<span\; class="notranslate">\; w</span>}}^{\mathrm{<span\; class="notranslate">\; k</span>}}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; no</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; =</span>\left\{\begin{array}{c}\mathrm{<span\; class="notranslate">\; 0</span>}<span\; class="notranslate">\; ,</span>{\stackrel{<span\; class="notranslate">\; \&OverBar;</span>}{\mathrm{<span\; class="notranslate">\; P</span>}}}_{\mathrm{<span\; class="notranslate">\; t</span>}}^{\mathrm{<span\; class="notranslate">\; k</span>}}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; no</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; ></span>\mathrm{<span\; class="notranslate">\; there</span>}\\ {\mathrm{<span\; class="notranslate">\; w</span>}}_{\mathrm{<span\; class="notranslate">\; N</span>}<span\; class="notranslate">\; \&times;</span>\mathrm{<span\; class="notranslate">\; 1</span>}}^{\mathrm{<span\; class="notranslate">\; k</span>}}<span\; class="notranslate">\; =</span>{<span\; class="notranslate">\; (</span>{\stackrel{<span\; class="notranslate">\; \&OverBar;</span>}{\mathrm{<span\; class="notranslate">\; P</span>}}}_{\mathrm{<span\; class="notranslate">\; t</span>}}^{\mathrm{<span\; class="notranslate">\; k</span>}}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; no</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; )</span>}^{<span\; class="notranslate">\; -</span>\frac{\mathrm{<span\; class="notranslate">\; 1</span>}}{\mathrm{<span\; class="notranslate">\; 2</span>}}}<span\; class="notranslate">\; ,</span>{\stackrel{<span\; class="notranslate">\; \&OverBar;</span>}{\mathrm{<span\; class="notranslate">\; P</span>}}}_{\mathrm{<span\; class="notranslate">\; t</span>}}^{\mathrm{<span\; class="notranslate">\; k</span>}}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; no</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; \&le;</span>\mathrm{<span\; class="notranslate">\; there</span>}\end{array}<span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 3</span>}<span\; class="notranslate">\; )</span>\right.$

${\stackrel{<span\; class="notranslate">\; ~</span>}{\mathrm{<span\; class="notranslate">\; the\; y</span>}}}_{\mathrm{<span\; class="notranslate">\; N</span>}<span\; class="notranslate">\; \&times;</span>\mathrm{<span\; class="notranslate">\; 1</span>}}^{\mathrm{<span\; class="notranslate">\; k</span>}}<span\; class="notranslate">\; =</span>{\mathrm{<span\; class="notranslate">\; w</span>}}_{\mathrm{<span\; class="notranslate">\; N</span>}<span\; class="notranslate">\; \&times;</span>\mathrm{<span\; class="notranslate">\; 1</span>}}^{\mathrm{<span\; class="notranslate">\; k</span>}}<span\; class="notranslate">\; .</span><span\; class="notranslate">\; \&times;</span>{\mathrm{<span\; class="notranslate">\; the\; y</span>}}_{\mathrm{<span\; class="notranslate">\; N</span>}<span\; class="notranslate">\; \&times;</span>\mathrm{<span\; class="notranslate">\; 1</span>}}^{\mathrm{<span\; class="notranslate">\; k</span>}}$

为第k根接收天线上加权后的检测数据矢量。在这种加权方式下，当检测窗内t子帧的某码片时刻的干扰功率值 P_t ^k(n)大于预先设定的门限thre时，表明该码片时刻受到了强干扰，需要在检测数据矢量中将该码片时刻对应的检测数据清除，则通过将该码片时刻对应的加权系数置0，进而使得加权后的检测数据矢量中对应该码片时刻的检测数据为0；当某码片时刻的干扰功率值P_t ^k(n)小于等于预先设定的门限thre时，则表明该码片时刻未受到强干扰，利用公式(3)所示的系数对该码片时刻的检测数据进行加权。Wherein, thre is a preset threshold value, w ^k (n) is the weighted value of the nth chip moment in the current t subframe in the detection window, $w_{N\&times;1}^k={\left[\begin{array}{cccc}{w}^k\left(1\right)& w^k\left(2\right)& ......& w^k\left(N\right)\end{array}\right]}^T$ is the weight vector of the kth receiving antenna, P _t ^k (n) is the interference power value at the nth chip moment in the current t subframe in the detection window,

is the weighted detection data vector on the kth receiving antenna. In this weighting mode, when the interference power value P _t ^k (n) at a certain chip time of subframe t in the detection window is greater than the preset threshold thre, it indicates that the chip time is subject to strong interference, and it needs to be In the detection data vector, the detection data corresponding to the chip time is cleared, and then the weight coefficient corresponding to the chip time is set to 0, so that the detection data corresponding to the chip time in the weighted detection data vector is 0; when When the interference power value P _t ^k (n) of a certain chip moment is less than or equal to the preset threshold thre, it indicates that the chip moment is not subject to strong interference, and the coefficient shown in the formula (3) is used for the chip moment The detected data are weighted.

After applying the above weighting method, the detection data corresponding to the time of the chip with strong interference in the detection data vector can be shielded from the detection data vector, and the interference in the uplink detection process can be suppressed, and the detection data after the interference is eliminated can be continued. Follow up.

Step 404, correlating the weighted detection data with the detected signature sequence, that is, SYNC_UL.

Step 405, performing multi-antenna combination on the correlation results obtained by all receiving antennas.

Step 406: Identify the result of multi-antenna combination through a signature sequence identification algorithm to obtain an uplink access detection result.

So far, the process of uplink access detection in this embodiment ends.

In the above embodiments, the operations of estimating the interference power envelope of the current subframe within the detection window and weighting the detection vector are performed sequentially. Specifically, when the detection data vector of the current subframe is weighted in step 403, the interference power envelope estimation result of the current subframe in the detection window is used to carry out, that is, the execution of step 403 uses the result of step 402, so the step 402 and 403 are performed sequentially.

Compared with the implementation manners in the foregoing embodiments, the operations of estimating the interference power envelope of the current subframe within the detection window and weighting the detection vector may also be performed in another order or in parallel. Since the estimation of the interference power envelope gradually converges to a certain power in a recursive manner, when weighting the detection data vector of the current subframe, the interference power envelope of the previous subframe of the current subframe can also be used Estimated results are performed.

When using the interference power envelope estimation of the previous subframe of the current subframe to weight the detection data vector of the current subframe, the difference from the embodiment shown in FIG. 4 is that when the uplink access detection is performed in the t subframe, The execution of step 403 is carried out according to the stored previous subframe, that is, the interference power envelope result of the (t-1) subframe in the detection window, rather than the result of step 402, so the execution of step 403 is not necessarily limited to the step 402. Steps 402 and 403 may be performed in parallel or in reverse order.

Specifically, in this embodiment, it is necessary to further include before step 401: estimating the interference power envelope of the subframe before the current t subframe, that is, the (t-1) subframe, and the estimation process can use The above-mentioned method in step 402 of FIG. 4 is performed, and the estimation result is stored for weighting the detection data vector of the current t subframe.

In step 403, the formula for weighting the detection data vector of the current t subframe may be,

${\mathrm{<span\; class="notranslate">\; w</span>}}^{\mathrm{<span\; class="notranslate">\; k</span>}}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; no</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; =</span>\left\{\begin{array}{c}\mathrm{<span\; class="notranslate">\; 0</span>}<span\; class="notranslate">\; ,</span>{\stackrel{<span\; class="notranslate">\; \&OverBar;</span>}{\mathrm{<span\; class="notranslate">\; P</span>}}}_{\mathrm{<span\; class="notranslate">\; t</span>}}^{\mathrm{<span\; class="notranslate">\; k</span>}}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; no</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; ></span>\mathrm{<span\; class="notranslate">\; there</span>}\\ {\mathrm{<span\; class="notranslate">\; w</span>}}_{\mathrm{<span\; class="notranslate">\; N</span>}<span\; class="notranslate">\; \&times;</span>\mathrm{<span\; class="notranslate">\; 1</span>}}^{\mathrm{<span\; class="notranslate">\; k</span>}}<span\; class="notranslate">\; =</span>{<span\; class="notranslate">\; (</span>{\stackrel{<span\; class="notranslate">\; \&OverBar;</span>}{\mathrm{<span\; class="notranslate">\; P</span>}}}_{\mathrm{<span\; class="notranslate">\; t</span>}}^{\mathrm{<span\; class="notranslate">\; k</span>}}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; no</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; )</span>}^{<span\; class="notranslate">\; -</span>\frac{\mathrm{<span\; class="notranslate">\; 1</span>}}{\mathrm{<span\; class="notranslate">\; 2</span>}}}<span\; class="notranslate">\; ,</span>{\stackrel{<span\; class="notranslate">\; \&OverBar;</span>}{\mathrm{<span\; class="notranslate">\; P</span>}}}_{\mathrm{<span\; class="notranslate">\; t</span>}}^{\mathrm{<span\; class="notranslate">\; k</span>}}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; no</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; \&le;</span>\mathrm{<span\; class="notranslate">\; there</span>}\end{array}\right.$

${\stackrel{<span\; class="notranslate">\; ~</span>}{\mathrm{<span\; class="notranslate">\; the\; y</span>}}}_{\mathrm{<span\; class="notranslate">\; N</span>}<span\; class="notranslate">\; \&times;</span>\mathrm{<span\; class="notranslate">\; 1</span>}}^{\mathrm{<span\; class="notranslate">\; k</span>}}<span\; class="notranslate">\; =</span>{\mathrm{<span\; class="notranslate">\; w</span>}}_{\mathrm{<span\; class="notranslate">\; N</span>}<span\; class="notranslate">\; \&times;</span>\mathrm{<span\; class="notranslate">\; 1</span>}}^{\mathrm{<span\; class="notranslate">\; k</span>}}<span\; class="notranslate">\; .</span><span\; class="notranslate">\; \&times;</span>{\mathrm{<span\; class="notranslate">\; the\; y</span>}}_{\mathrm{<span\; class="notranslate">\; N</span>}<span\; class="notranslate">\; \&times;</span>\mathrm{<span\; class="notranslate">\; 1</span>}}^{\mathrm{<span\; class="notranslate">\; k</span>}}$

为第k根接收天线上加权后的检测数据矢量， P_t-1 ^k(n)为检测窗内(t-1)子帧的第n个码片时刻的干扰功率值。其中，(t-1)子帧的干扰功率包络估计 P^k(t-1)，是在(t-1)子帧进行干扰功率包络估计时得到并存储下来的。Wherein, thre is a preset threshold value, w ^k (n) is the weighted value of the nth chip moment of the current t subframe in the detection window, $w_{N\&times;1}^k={\left[\begin{array}{cccc}{w}^k\left(1\right)& w^k\left(2\right)& ......& w^k\left(N\right)\end{array}\right]}^T$ is the weight vector of the kth receiving antenna,

is the weighted detection data vector on the kth receiving antenna, and P _t-1 ^k (n) is the interference power value at the nth chip moment of the (t-1) subframe within the detection window. Wherein, the interference power envelope estimation P ^k (t-1) of the (t-1) subframe is obtained and stored when the interference power envelope estimation is performed in the (t-1) subframe.

The estimation of the interference power envelope in step 402 is still performed on the current t subframe, and the obtained interference power envelope estimation result is stored for use in the interference power envelope estimation of the next subframe.

It can be seen from the above process that, while the specific implementation of the present invention basically retains the frame flow of the existing uplink access detection method, it uses the estimation of the interference power envelope and weights the detection data based on the estimation to realize the detection of the uplink access detection method. The interference elimination in the access detection process effectively improves the anti-interference ability of the system access detection and improves the detection performance of the system.

The effect of the uplink access detection method in the embodiment of the present invention is described below by comparing with the simulation of the prior art. In a TD-SCDMA system with eight transmit antennas and one receive antenna, the methods shown in Figure 4 and Figure 2 are used for uplink access detection respectively, and the detection window is set to GP+UpPTS period, then after shaping filtering and The detection data vector obtained after sampling is y _256×1 (t)=[y _t (1) y _t (2) ... y _t (256)] ^T .

In Fig. 5, the curve 501 represents the relationship between the SNR and the detection probability of the system when the GP+UpPTS period is not interfered by the DwPTS period; It is a relationship diagram of the signal-to-noise ratio and the detection probability of the system when performing uplink access detection with the method shown in FIG. 2 .

For uplink access detection using the method shown in Figure 4, the interference power envelope estimation is performed on the detection data vector y _256×1 (t), and the interference power envelope estimation result P _256×1 is specifically obtained by using formula (2) ^k (t); then use the weighting coefficient of the strong interference chip moment exceeding the threshold value to be set to 0, and the weighting coefficient of the other chip moments to be set to 1 to weight the detection data vector; finally use the weighted detection data vector to carry out Correlation calculation, multi-antenna combination and signature sequence identification, and then obtain the result shown in curve 502 in FIG. 5 .

When using the method shown in Figure 2 to perform uplink access detection, the detection data vector y _256×1 (t) is directly used to perform correlation calculation, multi-antenna combination and signature sequence identification, and then obtain the curve 503 shown in Figure 5 result.

It can be seen from Fig. 5 that when the GP+UpPTS period is interfered by the signal of the DwPTS period, the method of the embodiment of the present invention can obtain a higher detection probability, and with the strengthening of the interference, that is, the reduction of the signal-to-noise ratio, the present invention The greater the performance improvement of the embodiments relative to the method shown in FIG. 2 .

The above are only preferred embodiments of the present invention, and are not intended to limit the protection scope of the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention shall be included within the protection scope of the present invention.

Claims (10)

1. A method for uplink access detection, characterized in that the method comprises: a. Perform shaping filtering and sampling on the received data of the current subframe located in the detection window of all receiving antennas to obtain the detected data vector of the current subframe of each receiving antenna; b. Weighting the detection data vectors of the current subframe of each receiving antenna according to the estimation of the interference power envelope in the detection window on each receiving antenna; c. Correlating the weighted detection data vector corresponding to each receiving antenna with the detected signature sequence; performing multi-antenna combination on the obtained correlation calculation results of all receiving antennas, and performing signature sequence identification on the combined result. 2. The method according to claim 1, wherein the detection window in step a is any time period during which uplink pilot signals may be received. 3. The method according to claim 2, characterized in that, the arbitrary time period in which the uplink pilot signal may be received is: a time period consisting of a guard interval and an uplink pilot time slot, or a time period consisting of a guard interval and an uplink pilot time slot The time period formed by the uplink pilot slot and the first regular slot immediately following the uplink pilot slot. 4. The method according to claim 1, wherein the interference power envelope estimation in step b is the interference power envelope estimation of the current subframe or the interference power envelope estimation of the previous subframe of the current subframe . 5. The method according to claim 4, wherein when the interference power envelope estimation is the interference power envelope estimation of the current subframe, the interference power envelope in the detection window based on the receiving antenna Estimation is performed after step a. 6. The method according to claim 4, wherein when the interference power envelope estimation is the interference power envelope estimation of the previous subframe of the current subframe, the detection window on the receiving antenna according to The estimation of the interference power envelope is performed before step a. 7. The method according to claim 6, characterized in that step b further comprises: estimating the interference power envelope of the current subframe within the detection window, and storing the estimation result for use in the detection of the next subframe within the window Estimation of the interference power envelope of . 8. The method according to any one of claims 5 to 7, wherein the estimation of the interference power envelope in the detection window on each receiving antenna is: ${\mathrm{<span\; class="notranslate">\; P</span>}}_{\mathrm{<span\; class="notranslate">\; N</span>}<span\; class="notranslate">\; \&times;</span>\mathrm{<span\; class="notranslate">\; 1</span>}}^{\mathrm{<span\; class="notranslate">\; k</span>}}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; t</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; =</span>{\mathrm{<span\; class="notranslate">\; the\; y</span>}}^{<span\; class="notranslate">\; *</span>}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; t</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; .</span><span\; class="notranslate">\; \&times;</span>\mathrm{<span\; class="notranslate">\; the\; y</span>}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; t</span>}<span\; class="notranslate">\; )</span>$ P ^k (t) = βP ^k (t) + (1-β) P ^k (t-1) Among them, t is the subframe number for estimation of the interference power envelope in the detection window, k is the index of the receiving antenna, Pk(t) is the interference power envelope estimate in the t subframe detection window of the kth receiving antenna, y(t) is the detection data vector of t subframe, (.×) means that the elements of the vector are multiplied correspondingly to get A new vector, * means conjugate operation; β is a positive real number less than or equal to 1. 9. The method according to claim 1, wherein the threshold is preset, and the weighting of the detection data vectors of the current subframe of each receiving antenna in step b is: Compare the estimated value of the interference power at each chip time in the detection window with the preset threshold, if the estimated value of the interference power at a certain chip time is greater than the preset threshold, the detection data vector corresponding to the chip time The weighted value of the detected data is set to 0, and if the estimated value of interference power at a certain chip time is less than or equal to the preset threshold, non-zero weighting is performed on the detected data corresponding to the chip time in the detected data vector. 10. The method according to claim 9, wherein the non-zero weighting of the detection data corresponding to the chip moment in the detection data vector is: $w^k\left(\mathrm{no}\right)={\left({\stackrel{\&OverBar;}{P}}_t^k\left(\mathrm{no}\right)\right)}^{-\frac{1}{2}},$ Among them, t is the subframe number of the interference power envelope estimation in the detection window, n is the chip time index value, w ^k (n) is the detection data corresponding to the nth chip time in the detection data vector The weighting coefficient, P _t ^k (n) is the estimated value of the interference power corresponding to the nth chip moment in the detection window.

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