JP2012034366A - Device, method, and terminal device for performing synchronization detection in time division duplex system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a device for performing synchronization detection in a system of a TDD mode.SOLUTION: The device includes a normalizing means which is arranged so as to perform a normalizing process so that, for a sample sequence for synchronization detection in a signal received by a terminal device that executes synchronization detection, each of the samples in the sample sequence is normalized based on a parameter for the amplitude of all samples within a predetermined range around the sample, and a synchronization detection means which is arranged so as to execute the synchronization detection according to the sample sequence outputted and normalized by the normalizing means. Further, a method which executes synchronization detection in a system of a TDD mode is provided. The sample for the synchronization detection is normalized based on an element related to electric power, of all samples within the predetermined range around it, and the normalized sample is used for the synchronization detection. Consequently the interference of an uplink signal in the synchronization detection can be suppressed, thereby, detection time can be shorter.

Description

  The present invention relates to a communication technology field, and more particularly to an apparatus and method for performing synchronization detection in a communication system using a TDD (Time Division Duplex) mode, and a terminal apparatus including such an apparatus.

  3GPP Long Term Evolution (LTE) systems have Time Division Duplex (TDD) mode and Frequency Division Duplex (FDD) mode . In the frequency division duplex mode, the upstream signal and the downstream signal are transmitted at different frequencies. On the other hand, the upstream signal and downstream signal in the time division duplex mode are transmitted in different time zones of the same carrier.

  In the TDD-LTE system in the time division duplex mode, as shown in Table 1 below, seven types of frame structure arrangements are defined by the 3GPP standard. In Table 1, “D” indicates a downlink subframe, “U” indicates an uplink subframe, and “S” indicates a special subframe. Each subframe is composed of two slots having a length of 1 ms and a length of 0.5 ms.

FIG. 1 shows a TDD frame structure of a half subframe. The special subframes include downlink slot DwPTS, uplink / downlink conversion interval GP, and uplink slot UpPTS. The primary synchronization signal (Primary synchronization symbol, PSS) is located in the # 1 and # 6 subframes (in another half subframe not shown), and the secondary synchronization symbol (SSS) is in the # 0 subframe And # 5 subframe (in another half subframe not shown). As shown in FIG. 1, PSS is located in the third symbol of DwPTS, while SSS is located in the last symbol of the # 0 subframe. In a communication system based on TDD, a terminal device can perform synchronization with time and frequency of an appropriate cell by performing PSS detection. Then, after performing PSS detection, frame timing and cell ID can be obtained by further detecting SSS. Thereby, cell search is realized.

According to the 3GPP standard, the PSS signal is a Zadoff-Chu sequence with a length of 62 as shown in the following formula (1), and there are three types.

Here, n _ZC is one selected from {25, 29, 34}.

FIG. 2 is a schematic diagram showing the sequence. As shown in the figure, the sequence is located on 31 left and right subcarriers centered on DC, and c _nZC (31) corresponding to the DC subcarrier is set to 0. The five subcarriers on both sides of the sequence are similarly set to zero. A total of 72 subcarriers correspond to 6 RBs (resource blocks) in the center. The PSS sequences in subframe # 1 and subframe # 6 are the same.

  In general, a detection method using a matched filter is employed to detect a PSS signal. A search time of at least 5 ms is required to detect the position of the PSS symbol when the timing is unknown.

As shown in the following formula (2), the SSS signal is formed by weaving two m sequences having a length of 31, and has a total of 168 sequences. As shown in FIG. 3, the subcarriers are set to 0 for every five RBs located on both sides of the sequence, located in the six RBs centered on the carrier as in the PSS. The difference is that the SSS sequences located in subframe # 0 and subframe # 5 are different.

  The specific generation means for each of the above sequences can refer to the related standard 3GPP 36.211 and will not be described in detail here.

  The SSS detection means is generally based on code sequence matching detection in the frequency domain. Further, when the type of CP (cyclic prefix) is unknown, it is necessary to blindly detect the type of CP using SSS.

  For convenience of explanation, PSS detection and a combination of PSS detection and SSS detection are hereinafter referred to as “synchronous detection”. Synchronization detection can be used, for example, for realizing time synchronization and frequency synchronization with a base station or cell search processing by a terminal device. Regarding the types of cell search, there are mainly an initial cell search and an adjacent cell search. The initial cell search is used for initial network access, synchronizes the time and frequency between the terminal device and the target base station, and further detects the best cell ID of the signal by the terminal device to realize network access It is intended to do. The neighbor cell search includes a neighbor cell selection and a cell switch. In the neighbor cell search, the terminal device needs to perform a search to establish synchronization with the neighbor cell and detect the neighbor cell ID and the signal strength of the neighbor cell.

  FIG. 4 shows an example in which the terminal device performs synchronization detection in the TDD-LTE system. In this example, it is assumed that the terminal device UE1 performs synchronization detection for initial network access (for example, when UE1 is activated). In general, when timing information is not acquired, the terminal device UE1 needs to perform a search for at least a half frame time to acquire a frame timing. As described above, since the uplink and downlink signals operate at the same frequency in the TDD-LTE system, the terminal apparatus UE1 can transmit the downlink (Downlink, DL) signal from the base station (eNodeB) within the time of one frame. Uplink (UL) signals from the terminal devices UE2 and UE3 that are adjacent to each other are received. Due to the attenuation of the radio channel, for example, when the terminal device is located at the edge of the cell, the downlink signal from the base station eNodeB received by the terminal device UE1 may become very weak. Conversely, the adjacent terminal devices UE2 and UE3 often have a direct path with the terminal device UE1 that performs synchronization detection. As shown in FIG. 5, since the distance is short, the uplink signal received by the terminal device UE1 may be several tens of dB higher than the downlink signal. At this time, the common synchronization signal detection algorithm is invalidated due to the influence of uplink interference. Since SSS detection needs to use the detection result information by PSS detection, the above-mentioned disadvantageous effects also exist in both PSS detection and / or SSS detection. Therefore, the PSS detection and the cell search processing performance by SSS detection are also affected. Note that the number of terminal devices that may adversely affect the terminal device UE1 that performs synchronization detection may be different from that shown in FIG. 4, and may be more than one or two, for example. However, a similar problem exists.

  As can be seen from the above, how to realize synchronization detection capable of efficiently suppressing uplink signal interference in a wireless communication system is still a problem to be solved.

  The following briefly describes the present invention and provides a basic understanding of some aspects of the present invention. This brief description is not exhaustive for the invention. Its purpose is not to determine the essential or critical part of the invention, nor to limit the scope of the invention, but merely to provide some concepts in a simplified form and to provide a more detailed explanation below. It is in the preceding explanation.

  In view of the problems existing in the prior art, according to the synchronization detection apparatus and method provided in the embodiments of the present invention, in synchronization detection of the system in the TDD mode, a sample for synchronization detection is set to a predetermined range around it. After normalization based on a parameter related to the amplitude of all samples in (for example, a statistic related to amplitude or an average value related to amplitude), synchronous detection is performed using the normalized sample.

  An embodiment according to the present invention is an apparatus for performing synchronization detection in a communication system using the TDD mode, wherein the sample is detected with respect to a sample sequence for synchronization detection in a signal received by a terminal apparatus that performs synchronization detection. Normalization means configured to perform a normalization process so that each of the samples in the sequence is normalized based on the amplitude-related parameters of all samples in a predetermined range around the sample; An apparatus is provided comprising synchronization detection means configured to perform synchronization detection in response to the normalized sample sequence output by the normalization means.

  Another embodiment according to the present invention is a method for performing synchronization detection in a communication system in TDD mode, and for a sample sequence for synchronization detection in a signal received by a terminal device that performs synchronization detection, A normalization process is performed so that each of the samples in the sample sequence is normalized based on the amplitude-related parameters of all the samples in a predetermined range around the sample, and obtained by the normalization process. A method is provided that includes performing synchronization detection based on a normalized sample sequence.

  Another embodiment according to the present invention further provides a machine executable program. The synchronization detection method can be executed when the machine reads and executes the program.

  Another embodiment according to the present invention further relates to a storage medium for storing the program.

  By performing synchronization detection using the apparatus and method according to each embodiment of the present invention, it is possible to obtain the benefit of suppressing the interference of uplink signals in the synchronization detection of the TDD-LTD system and improving the synchronization detection performance. . In addition, the benefit of shortening the synchronization detection time can be obtained.

The above and other objects, features, and advantages of the present invention can be understood more easily by describing embodiments of the present invention with reference to the drawings. The parts in the drawings are not drawn to scale, but merely illustrate the principles of the invention. Corresponding parts in the drawings may be enlarged to show and explain parts of the invention for convenience. That is, it may be shown enlarged to be larger than another part in an exemplary apparatus actually manufactured according to the present invention. In the drawings, the same or similar technical features or parts are denoted by the same or similar drawing symbols.
It is a schematic diagram showing a TDD frame structure frame of a half frame of a certain kind of frame structure arrangement defined by the 3GPP standard in the TDD-LTE system. It is a schematic diagram which shows the structure of the PSS sequence prescribed | regulated by 3GPP specification. It is a schematic diagram which shows the structure of the SSS sequence prescribed | regulated by 3GPP specification. It is a schematic diagram which shows that terminal unit UE1 performs the synchronous detection for initial stage network access in a TDD-LTE system. FIG. 5 is a schematic diagram showing that the synchronization detection as shown in FIG. 4 is adversely affected by uplink signals from adjacent terminal devices. FIG. 3 is a structural diagram illustrating an apparatus for performing synchronization detection in a TDD-LTD system according to an embodiment of the present invention. FIG. 7 is a structural diagram illustrating an embodiment of normalization means included in the synchronization detection device illustrated in FIG. 6. It is a schematic diagram which shows that the normalization means contained in the synchronous detection apparatus of the Example by this invention implement | achieves a normalization process. It is a schematic diagram which shows the edge process which the normalization means performed in the synchronous detection apparatus of the Example by this invention. It is a schematic diagram which shows the structure of the area GAP used in order to search a different frequency cell prescribed | regulated by 3GPP specification. FIG. 7 is a structural diagram illustrating a modification of the synchronization detection device of the embodiment according to the present invention illustrated in FIG. 6. FIG. 7 is a structural diagram showing another modification of the synchronization detection means of the synchronization detection device of the embodiment shown in FIG. 6. FIG. 7 is a structural diagram showing another modification of the synchronization detection means of the synchronization detection device of the embodiment shown in FIG. 6. 4 is a flowchart illustrating a method for performing synchronization detection in the TDD-LTD system according to the embodiment of the present invention. FIG. 15 is a structural diagram illustrating an embodiment of normalization processing steps included in the synchronization detection method illustrated in FIG. 14. (A)-(b) is a comparison figure which each shows the TDD signal which the terminal device received when the conventional method and the synchronous detection apparatus and method of the Example by this invention were utilized. (C)-(d) is a comparison figure which respectively shows the synchronous detection result which can be acquired using the conventional method and the synchronous detection apparatus and method of the Example by this invention. It is a comparison figure which shows the error detection probability of PSS acquired using the conventional method and the synchronous detection apparatus and method of the Example by this invention. 1 is a structural diagram illustrating a general-purpose computer system capable of realizing a synchronization detection apparatus and method according to an embodiment of the present invention.

  Embodiments of the present invention will be described below with reference to the drawings. Elements and features described in one drawing or one type of embodiment of the invention may be combined with elements and features shown in one or more other drawings or embodiments. Here, for the sake of clarity, in the drawings and description, the display and description of parts and processes that are well known to those skilled in the art and are not related to the present invention are omitted.

  FIG. 6 is a structural diagram illustrating an apparatus 600 for performing synchronization detection in the TDD-LTD system according to the embodiment of the present invention. As shown in the figure, the synchronization detection apparatus 600 includes a normalization unit 610 and a synchronization detection unit 620. The normalizing means 610 is configured such that, for a sequence of samples for synchronization detection in a signal received by a terminal device that performs synchronization detection, each sample of the sample sequence includes all samples in a predetermined range around the sample. The normalization process is performed so that the normalization is performed based on the parameter related to the width and the parameter related to the width. The synchronization detection means 620 is configured to perform synchronization detection based on the normalized sequence of samples output by the normalization means 610.

  As described above, the interference due to the uplink signal in the conventional synchronization detection method is related to the signal amplitude or the power level. The normalization performed by the synchronization detection apparatus according to this embodiment of the present invention is performed in consideration of factors related to the amplitude or power of all samples in a specific range around the sample on which the normalization processing is performed. The adverse effect of the uplink signal of another terminal device close to the terminal device performing synchronization detection on the synchronization detection by the terminal device can be effectively eliminated, or at least significantly reduced. For example, judgment errors are reduced, and synchronization detection accuracy is improved. In FIG. 16A (a) and (b) to be described later, an example of simulation is given, and a comparison of TDD signals received by the terminal device when the conventional method and the synchronization detection device and method of the embodiment according to the present invention are used. The figure is shown. As shown in (a) of FIG. 16A, the TDD signal received by the terminal includes a downlink (DL) signal from the base station, a noise signal in the GP, and uplink (UL) signals from other UEs. including. Here, the upstream signal power is about 40 dB higher than the downstream signal power, and the characteristics of the unstable signal appear in the signal. As shown in (b) of FIG. 16A, after the normalization process in the embodiment according to the present invention is performed, the signal has a waveform without a sharp undulation and becomes very stable. In particular, uplink interference that is significantly higher than downlink interference is suppressed.

  FIG. 7 is a structural diagram showing an embodiment 700 of normalization means included in the synchronization detection apparatus 600 shown in FIG. As shown in the figure, the normalization means 700 according to the embodiment relates to an average value or amplitude related to amplitude of all samples in a predetermined range around the sample, for each sample in the sequence of samples. A normalization factor calculation sub-unit 720 configured to calculate a statistical value and use the average value or the statistical value as a normalization factor corresponding to the sample; and a sequence of samples of the length of time in the predetermined range A delay sub-means 710 arranged to be delayed by a time corresponding to a portion, and for each sample of the sequence of samples, the delay sample corresponding to the sample output by the delay sub-means 710, The sample is normalized by dividing by the normalization factor corresponding to the sample output by the normalization factor calculation sub means 720. And a normalization sub-means 730 configured to.

The operation of the normalization means will be described below using a specific example.
In the synchronization detection process, the signal r (m, k) in the time domain corresponding to the six RBs (resource blocks) at the center of the carrier among the signals received from the antenna of the terminal device is synchronized. A sample to be executed. The sample is a signal having a real part and an imaginary part. Here, m corresponds to a signal from the m-th receiving antenna, and k is a sample serial number. A sequence of samples for synchronization detection is constituted by such a plurality of samples.

In the normalization factor calculation means 720, for example, the normalization factor N (m, k) related to the input sample r (m, k) is calculated using the following mathematical formula.

In the above equation (3), W _norm indicates the length of a normalizing window. Here, the “normalization window” is an example of a predetermined range related to the normalization process for the sample r (m, k) mentioned earlier. The predetermined range is a range around the sample on which the normalization process is performed (including the sample). All samples within the normalization window (including sample r (m, k)) need to participate in the process given by equation (3) above. The length of the normalization window is an integer and can take a value from 2 to 256, for example, any one of {2, 4, 8, 16, 64, 128, 256}. Preferably, for example, any of 8-128 can be taken. The length of the normalization window can be specified through a method such as a simulation test based on, for example, communication system parameters and desired performance (for example, cell search time in which synchronization detection is used). . Details are not described here.

  As can be seen from the above, the processing according to the equation (3) represents the amplitude value information of the sample completely and considers the actual value of each sample in the normalization window in order to consider the convenience of realization. The normalization factor N (m, k) corresponding to the input sample r (m, k) is calculated using the method of calculating the average value for the sum of the norm of the part and the norm of the imaginary part .

In the delay sub-unit 710, the received signal samples are delayed by, for example, W _norm / 2 sample times to obtain delayed samples r (m, k) _delay . This is intended to realize normalization with a central normalization window. That is, for the received signal sample r (m, k), the normalization factor is from W _norm / 2 samples before the sample to W _norm / 2 samples after the sample (the sample r (including m, k)) (for example, the norm of the real part and the norm of the imaginary part of the sample).

In the normalization sub means 730, normalization is performed by the following formula using the delayed sample r (m, k) _delay and the corresponding normalization factor N (m, k).

  FIG. 8 shows an example in which normalization processing is realized by the central normalization window. As described above, in such a normalization process, by delaying the normalized sample, the normalized output corresponding to the sample is not from the rightmost side of the normalization window, but from the center of the window. Is output. That is, the use of a causal window is prevented. If a causal window is employed, samples received before a sample r (m, k) in that window are used to identify the normalized output corresponding to the sample r (m, k). That is, the normalized output should be output from the rightmost side of the window. As shown in FIG. 8, when the rightmost side of the normalization window is located at the boundary between the GP and the uplink (UL) signal, the normalization window may be partially or entirely located in the GP section. , A very small normalization factor can be obtained by calculation using the above equation (3). For this reason, dividing the large signal r (m, k) at the boundary between the GP and the upstream signal by a small normalization factor causes a phenomenon that the signal is erroneously amplified, which adversely affects the accuracy of synchronization detection. It will be done.

In the example shown in FIG. 8, the center normalization window is adopted as the normalization window. That is, the normalized output of the sample r (m, k) that has been subjected to the normalization process is output from the center of the normalization window of the center. As an alternative embodiment, the normalization factor can be calculated using various normalization windows of various eccentricities as follows.

Configuration wherein the equation (5) and (6), to calculate the normalization factor disposed adopted by the leftmost respectively from W _norm / 4 and 3W _norm / 4 apart eccentric normalized window of normalization window It is. That is, the normalization output of the sample on which the normalization process is performed is output from the positions W _norm / 4 and 3 W _norm / 4 away from the leftmost side of the normalization window. In contrast, in these two cases, in the delay sub-means 710, the received signal samples are delayed by W _norm / 4 and 3 W _norm / 4 sample times, respectively. That is, the delay sub means delays the sequence of samples for synchronization detection by a time corresponding to a part of the length of time of the normalization window.

In the above embodiment, the normalization factor is calculated by obtaining an average value for the sum of the norm of the real part and the imaginary part of all samples in the normalization window. Since the statistical characteristics of the real part and the imaginary part of the received signal match, as an alternative example, the average value of the real part norm of all the samples in the normalization window or the average value of the norm of the imaginary part as follows: The normalization factor can be obtained using the above.

  The above equation (7) calculates the normalization factor by the average value of the norm of the real part of all samples in the normalization window, and the equation (8) is the average value of the norm of the imaginary part of all samples in the normalization window. The normalization factor is calculated by The average value of the norm of the real part of the sample, the average value of the norm of the imaginary part, or the average value of the sum of the two are all average values related to the amplitude or power of the sample. However, the present invention is not limited to these, and it may be considered to calculate the normalization factor by employing any other suitable parameter value depending on the amplitude of the sample. For example, any other suitable statistic that correlates with the amplitude or power of the sample, for example, a first order statistic such as the average or maximum of the norm of the sample, or a higher order such as the average power The normalization factor may be calculated using the above statistic. In addition, the arrangement of the normalization window at the center is used in the above equations (7) and (8). Of course, such a normalization factor calculation means may be applied to the arrangement of eccentric normalization windows.

  Since the delay processing is performed on the sample to be normalized, the accuracy of synchronization detection can be further improved.

  According to the replaceable embodiment, the normalization factor calculation sub means 720 may further include an edge processing unit (not shown). FIG. 9 is a schematic diagram illustrating an example of edge processing executed by the normalization unit in the synchronization detection device according to the embodiment of the present invention.

In this example, the length of the normalization window W _norm is 8. For convenience of explanation, the center normalization window arrangement is used here. Arabic numerals 1, 2,..., 9 indicate sample serial numbers to be normalized. In the normalization window 902 shown in FIG. 9A, after the delay of W _norm / 2 samples, the first normalization output starts corresponding to the received sample r (1). That is, the normalized output of the sample r (1) is given to the fourth sample from the left side of the normalization window 902. Obviously, since the sequence of samples enters sequentially from the left side of the normalization window 902, an attempt is made to normalize the first sample r (1) in the initial stage of the normalization process shown in FIG. When doing so, the entire normalization window 902 is not filled with the sample, ie the right side of the normalization window 902 is empty. In this case, if the normalization window 902 is entirely filled with an appropriate sample, the speed of the normalization process can be improved, and the speed of the synchronization detection process can be further improved.

  Specifically, the edge processing unit extends forward (i.e., copies) based on the sample that has undergone normalization processing in the initial stage of the normalization processing, i.e., forwards from the sample in the forward direction. The entire normalization window may be filled using a sample. For example, as shown in FIG. 9 (b), the sample r (1) on which the current normalization process is performed is extended to the previous four samples, so that eight samples in the normalization window 902 are displayed. A sample is constructed, and thereafter a normalization process is performed on the sample r (1) based on the filled normalization window. As shown in FIG. 9 (c), r (2) is extended to the previous three samples corresponding to the sample r (2) to be normalized. Similarly, if processing is performed up to the output of the normalized result corresponding to the fourth sample r (4) (as shown in FIG. 9 (e)), the edge processing corresponding to the initial stage is completed, As shown in (f) and (g) of FIG. 9, it is possible to proceed to a normal normalization process (for example, the processes according to the above formulas (3) to (8)). In the example shown in FIG. 9, the initial stage of the normalization process is the blanking that needs to be filled with the sample to be processed in the normalization window after the normalization process starts for the first sample. This is the time period until the space runs out. Of course, if necessary, another suitable time zone may be selected as the initial stage of the normalization process.

  In the previous example, the normalization window 902 was filled with the sample that is subjected to the normalization process in the initial stage of the normalization process. However, according to the replaceable embodiment, the normalization window 902 is filled with a fixed value. You may do it. For example, a value corresponding to half of the range of the A-D converter may be adopted to perform such forward extending filling.

  Similarly, at the end of the normalization process (not shown in FIG. 9), no new sample to be processed enters, so one sample is empty on the left side of the normalization window 902 shown in FIG. It will become. Therefore, the edge processing unit extends backward based on the sample on which the normalization process is performed at the end stage of the normalization process, that is, the entire normalization window using the sample backward from the sample. May be configured to be filled. Similarly, according to a replaceable embodiment, such a backward extended filling may be performed using another suitable value, for example a value corresponding to half the range of the AD converter. Of course, the fixed value used for filling here may be the same as or different from the fixed value used for filling performed in the initial stage of the normalization process. In the example shown in FIG. 9, the end stage of the normalization process is the time period from the start of the blank space on the leftmost side of the normalization window to the end of the normalization process for the last sample. It is. Of course, if necessary, another suitable time zone may be selected as the end stage of the normalization process.

  As can be seen from the tests, when the normalized window employed is large, such edge processing methods can save at least half the window length time and improve the speed of synchronization detection.

  In addition, according to the 3GPP standard, different cell adjacent cell search needs to be completed within GAP (search interval of adjacent cells of different frequency). The GAP time is only 6 ms, and the terminal device needs to complete carrier conversion, synchronization signal detection and measurement during this period. In an asynchronous network, at least 5 ms is required to complete a cell search. For SSS detection, which performs correlation detection based on the detected PSS signal, because the channel estimation in SSS detection is based on PSS with three symbols separated (the TDD frame shown in FIG. 1). 5ms + 4 symbols are required to complete the cell search at different frequencies. FIG. 10 is a schematic diagram showing a configuration of a spatial GAP for cell search of different frequencies defined by the 3GPP standard. In FIG. 10, VCO indicates a voltage controlled oscillator that converts carriers when switching between a service cell and an adjacent cell. Needless to say, a high-performance VCO can shorten the time required for carrier conversion, but the price increases accordingly. To avoid using expensive voltage-controlled oscillators considering that there are two symbols between the primary synchronization signal (PSS) and the secondary synchronization signal (SSS) in the TDD-LTE system Therefore, it is necessary to shorten the synchronization detection time for cell search at different frequencies as much as possible. For this reason, it is particularly beneficial to use the edge processing method in the synchronous detection of cell searches at different frequencies. For example, when the normalization window has a particularly large length, for example, 128 samples, the edge processing method according to the embodiment of the present invention reduces the total length of one window at the start and end of normalization. Can be reduced.

Equations (9) and (10) below show how to realize normalization factor calculation including the edge processing.

Note that T _norm is the length of a sample corresponding to the time of a cell search related to synchronization detection (for example, it may be an initial synchronization search or an adjacent cell search). The parameter can be specified in advance based on detection performance by PSS detection and / or SSS detection included in system synchronization detection, for example. For example, depending on the actual situation, the sample length corresponding to the length of time such as 5 ms + 4 symbol, 5 ms + 2 symbol, etc. can be adopted.

When a fixed value (that is, a constant) is adopted to extend forward or backward with respect to the normalization window, the normalization factor including the edge processing is calculated according to the following formulas (11) and (12). The realization method is shown.

  The above formulas (9) to (12) calculate the normalization factor corresponding to the sample using the average value of the sum of the norm of the real part and the imaginary part of the corresponding sample. As shown in the equations (7) and (8), normalization processing including such edge processing is performed by means such as the average value of the norm of the real part or the average value of the norm of the imaginary part of the corresponding sample. Also good. Details are not described here.

  FIG. 11 is a structural diagram showing a modification of the synchronization detection apparatus according to the embodiment shown in FIG. As shown in the figure, the synchronization detection apparatus 1100 according to the modification is different from the synchronization detection means 600 shown in FIG. The said control means 1102 controls a synchronous detection apparatus so that a normalization process may be performed in a different mode based on the stage of the different cell search in which the terminal device was located.

  Specifically, for example, when the terminal device newly accesses the communication system, such as when the power is first turned on or restarted after shutdown, an initial cell search needs to be performed. In this case, the control unit 1102 controls the normalization unit 1104 so that the normalization process is always executed until the synchronization detection unit 1106 detects the ID of a service cell that can provide a service to the terminal device.

  When it is necessary to perform cell switching, for example, when the terminal device moves to the edge of the current service cell and the quality of service is reduced, the current service base station of the terminal device performs a neighbor cell search. To instruct. When the service base station instructs the terminal apparatus to perform the adjacent cell search of the same frequency, the 3GPP specifies that the cell of the same frequency is synchronous. The normalizing means 1104 is controlled so that normalization processing is performed within the range of two or 2.5 subframes. For example, according to the structure of the TDD frame structure shown in FIG. 1 above, between subframe # 0 and subframe # 1 or between subframe # 5 and subframe # 6 according to the timing of the service cell. The normalization means 1104 can be controlled to perform the normalization process. The time can be specified, for example, based on the synchronization accuracy of the base station (defined by the 3GPP standard) and the transmission delay of the radius of the correlation cell. Details are not described here.

  When the serving base station instructs the terminal apparatus to perform adjacent cell search of different frequencies, the control means 1102 performs normalization processing in the search space GAP of adjacent cells of different frequencies between the uplink signal and the downlink signal. The normalizing means 1104 is controlled to execute. For example, in a system based on the TDD mode, it is conceivable that the execution time of the normalization processing by the normalizing means can be set to an arbitrary time within the range of 5 ms + 1 symbol to 5 ms + 4 symbols by the SSS detection algorithm. Here, it is preferable to select 5 ms + 4 symbols.

  Since the execution unit of the normalization process can be controlled according to the actual situation so as to limit the execution time interval, it is possible to improve the performance of synchronization detection and reduce the power cost related to synchronization detection. For example, performance improvement such as power saving and energy saving can be realized by a terminal device that performs synchronization detection using such a synchronization detection device.

  The configurations and operation examples of the normalization unit 1102 and the synchronization detection unit 1106 of the synchronization detection device 1100 in FIG. 11 will not be described here because the description with respect to FIGS.

FIG. 12 is a structural view showing another modification of the synchronization detecting means of the synchronization detecting apparatus of the embodiment shown in FIG. As shown in FIG. 12, the detection means 1204 in the synchronous detection device 1200 according to the modified example employs each of three possible PSS sequences (as shown in FIG. 2) and has been normalized. Performs a correlation operation with the signal r _norm (m, k), and the PSS sequence (PSS ID) corresponding to the maximum correlation value within the synchronization detection range or a correlation value larger than a certain threshold and corresponding timing position (SSS timing) PSS detection sub means 1212 configured to detect. Furthermore, the frequency offset between the terminal and the base station can be detected by the PSS sequence. The configuration and operation example of the normalization unit 1202 in the synchronization detection device 1200 can be referred to the description with respect to FIGS.

FIG. 13 is a structural view showing still another modified example of the synchronization detecting means of the synchronization detecting apparatus of the embodiment shown in FIG. As illustrated in FIG. 13, the detection unit 1304 in the synchronization detection device 1300 according to the modification includes a PSS detection sub unit 1312 and an SSS detection sub unit 1316. The PSS detection sub means 1312 can execute functions and operations similar to the PSS detection sub means 1212 shown in FIG. The SSS detection sub means 1316 estimates the FFT position according to the length of the extended CP (cyclic prefix) and the normal CP based on the timing position included in the detection result of the PSS detection sub means 1312, and outputs the signal. Each can be detected by converting to the frequency domain. Finally, the magnitude of the maximum correlation peak at the two positions can be compared to determine whether it is an extended CP or a normal CP. When detecting the type of CP, it is assumed that the detection performance deteriorates due to the influence of the interference between the GP and the uplink signal in the synchronization detection processing. Therefore, the signal r _norm processed by the normalization means 1302 also in this embodiment. Detection is performed by inputting (m, k) to the SSS detection sub means. For SSS detection, correlation detection means using a PSS signal or non-correlation detection means using a difference can be employed. After the correlation detection is performed, the Cell ID (cell ID) of the adjacent base station can be acquired. The configuration and operation example of the normalization unit 1302 in the synchronization detection device 1300 will not be described here because the description with respect to FIGS.

  As described above, since PSS and / or SSS synchronization detection can be performed using a normalization process having improved performance, the cell search capability of the terminal device can be further improved.

  FIG. 14 is a flowchart illustrating a method 1400 for performing synchronization detection in a TDD mode communication system according to another embodiment of the present invention. As shown in the figure, the method 1400 begins at step S1410. In step S1420, normalization processing is performed on the sample sequence for synchronization detection in the signal received by the terminal device that performs synchronization detection, so that each sample in the sample sequence is surrounded by the sample. The samples are normalized based on parameters related to the amplitudes of all samples in the predetermined range. In step S1430, synchronization detection is performed based on the normalized sample sequence obtained in step S1420. For example, the method can be executed using the synchronization detection apparatus 600 shown in FIG. For specific operations and advantages, for example, the description for FIG. 6 can be referred to and will not be described here.

  FIG. 15 is a flowchart showing an embodiment of step S1420 for performing normalization processing included in the synchronization detection method shown in FIG. As shown in the figure, the synchronization detection method 1500 according to this embodiment includes step S1520 for performing normalization processing and step S1530 for performing synchronization detection. Step S1520 includes three substeps. In sub-step S1522, for each sample in the sample sequence, an average value related to amplitude or a statistical value related to amplitude of all samples in the predetermined range around the sample is calculated, and the average value or statistical value is calculated. The normalization factor corresponding to the sample is used. In sub-step S1526, the sample sequence is delayed by a time corresponding to a portion of the predetermined range of time length. In sub-step S1528, for each sample in the sample sequence, the delayed sample corresponding to the sample output in sub-step S1526 is divided by the normalization factor corresponding to the sample output in sub-step S1522. By doing so, the sample is normalized. For example, the method can be executed using the synchronization detection apparatus 700 shown in FIG. For specific operations and advantages, for example, the description for FIG. 7 can be referred to, and thus will not be described here.

  Here, the sub-step S1522 for performing normalization processing on the sample shown in the figure and the sub-step S1526 for delaying the sample sequence are executed according to the procedure shown in the figure, but in parallel. You may perform, or you may perform substep S1522 after performing substep S1526.

  According to one embodiment of the method 1500, the sub-step S1522 for calculating the normalization factor is, for each sample in the sample sequence, the norm of the real part of all samples in a predetermined range around the sample. Calculating a normalization factor corresponding to the sample by at least one of the average value, the average value of the norm of the imaginary part, and the average value of the sum of the norm of the real part and the norm of the imaginary part. For example, the method can be executed using the synchronization detection apparatus 700 shown in FIG. Specific operations and advantages are not described here because the description for FIG. 7 can be referred to.

  According to another replaceable embodiment of the method 1500, the sub-step S1522 for calculating the normalization factor performs an edge process that extends forward in the initial stage of the normalization process, and the initial stage of the normalization process. The edge processing can be performed so as to execute the edge processing extending backward. For example, the method can be executed using the synchronization detection apparatus 700 shown in FIG. For specific operations and advantages, for example, the description for FIGS.

  According to the replaceable embodiments of the methods 1400 and 1500, a control step may further be included. In the control step, when the terminal device performs an initial cell search, an adjacent cell search of the same frequency, and an adjacent cell search of a different frequency, the normalization process is controlled by controlling each step of performing the normalization process. . For example, the method can be executed using the synchronization detection apparatus 1100 shown in FIG. The specific operation and advantages are not described here because the description for FIG.

  According to the replaceable embodiments of the methods 1400 and 1500, the method may further include a sub-step for performing PSS synchronization detection, or both a sub-step for performing PSS synchronization detection and a sub-step for performing SSS synchronization detection. For example, the method can be executed using the synchronization detection devices 1200 and 1300 shown in FIGS. For specific operations and advantages, for example, the description of FIG. 12 and FIG. 13 can be referred to, and thus will not be described here.

  The synchronization detection device according to each of the embodiments of the present invention can be realized by software, hardware, firmware, or a combination thereof, for example. When the synchronization detection device is realized by hardware, a system such as an IC chip, a network card, or a USB-bar can be employed.

  Of course, the synchronization detection device according to each of the embodiments of the present invention may be realized as an independent functional configuration, or may be realized by being integrated with a corresponding terminal device. Therefore, a terminal device including such a synchronization detection device is also included in the protection scope of the present invention. Such a terminal device may include, for example, a mobile phone, a personal digital assistant, a laptop computer, and the like.

  Although the above description has been made in the context of a TDD-LTE system, the synchronization detection apparatus, method, and terminal apparatus according to each of the embodiments of the present invention are not limited to the TDD-LTE system, but also include the TD-LTE Advanced [LTEA]. It can also be applied to IMT-Advanced systems that are inherited from LTE systems in the future such as systems.

FIGS. 16A to 16B are comparison diagrams respectively showing a synchronization detection result that can be acquired using a conventional synchronization detection method and a synchronization detection apparatus and method according to an embodiment of the present invention. In the conventional synchronization detection, the received sample signal r (n) that has not been normalized is directly correlated with the PSS sequence [take correlation]. That is,

Note that id is the three known sequences of the PSS shown in FIG. 2, T _symbol is the number of samples corresponding to the length of one symbol, n is a sample serial number, and “*” is a conjugate operation. .

In the synchronization detection apparatus and method according to each embodiment of the present invention, the normalized sample signal r _N (n) is used for correlation with the PSS sequence. That is,

  As can be seen from the comparison between (c) and (d) of FIG. 16B, when the uplink interference signal is large, the maximum value of the correlation value is in the uplink portion (UL) in the conventional synchronization detection method. This is an incorrect timing because the correct timing (ie correct correlation peak) should be in the location corresponding to the PSS. In the synchronization detection apparatus and method according to each embodiment of the present invention, the correlation peak is at the correct timing position (ie, the correct correlation peak). Therefore, the performance of synchronization detection has been significantly improved.

  In addition, the inventors of the present invention performed a simulation for the AWGN channel under conditions where the uplink interference power is 10 dB higher than the downlink power, and measured the error detection probability of the PSS. FIG. 16C shows the result of the simulation test. As shown in FIG. 16C, in the conventional method that does not use the normalization process, the PSS error detection probability is about 66% and does not decrease as the SN ratio increases. This means complete expiration of the synchronization detection algorithm. On the other hand, when the synchronization detection apparatus and method according to the embodiment of the present invention is used, the error detection probability decreases to 0 as the SN ratio increases.

  As described above, detailed descriptions have been given through block diagrams, flowcharts and / or embodiments, and different implementation means of the apparatus and / or method according to the embodiments of the present invention have been described. When one or more functions and / or operations are included in these block diagrams, flowcharts, and / or embodiments, those functions and / or operations in these block diagrams, flowcharts, and / or embodiments will be described in various ways for those skilled in the art. Obviously, the hardware, software, firmware or any combination thereof can be implemented individually and / or jointly. In certain implementations, some portions of the subject matter described herein include application specific integrated circuits (ASICs), field programmable gate arrays (FPGAs), digital signal processing units (DSPs). Or in other integrated forms. On the other hand, for some aspects of the implementation means described herein, in whole or in part, the form of one or more computer programs (eg, one or more) executed on one or more computers. One or more computer programs executed on one computer system), one or more programs executed on one or more processors (eg executed on one or more microprocessors) One of ordinary skill in the art can envision equivalent implementations in an integrated circuit in the form of one or more programs), firmware, or any combination thereof. And according to the content disclosed in this specification, it would be possible for those skilled in the art to design a circuit for this disclosure and / or program code used in the software and / or firmware of this disclosure. Within range.

  For example, each component module, means, and sub means in the synchronization detection apparatus shown in FIGS. 6 to 7 and FIGS. 11 to 13 can be configured by software, firmware, hardware, or a combination thereof. When realized by software or firmware, a program constituting the software is installed from a storage medium or a network to a computer having a dedicated hardware configuration (for example, the general-purpose computer 1700 shown in FIG. 17). The computer can execute various functions when various programs are installed.

  FIG. 17 is a structural diagram showing a general-purpose computer system capable of realizing the synchronization detection apparatus and method according to the embodiment of the present invention. The computer system 1700 is merely illustrative, not implicitly limiting in scope of use or functionality of the methods and apparatus of the present invention. In addition, the computer system 1700 does not depend on any of the components shown in the exemplary computing system 1700, or a combination thereof.

  In FIG. 17, a central processing unit (CPU) 1701 executes various processes according to a program stored in a read-only memory (ROM) 1702 or a program uploaded from a memory unit 1708 to a random access memory (RAM) 1703. . The RAM 1703 further stores data necessary for the CPU 1701 to execute various processes as necessary. The CPU 1701, ROM 1702 and RAM 1703 are connected to each other via a bus 1704. An input / output interface 1705 is also connected to the bus 1704.

  An input unit 1706 (including a keyboard and a mouse), an output unit 1707 (including a display such as a cathode ray tube (CRT), a liquid crystal display (LCD), and a speaker), a memory unit 1708 (including a hard disk), A communication unit 1709 (including a network interface card such as a LAN card and a modem) is connected to the input / output interface 1705. A communication unit 1709 executes communication processing via a network, for example, the Internet. A drive 1710 is also connected to the input / output interface 1705 as necessary. A removable medium 1711 such as a magnetic disk, an optical disk, a magneto-optical disk, a semiconductor memory or the like is attached to the drive 1710 as necessary, and a computer program read from the medium 1711 is stored in the memory unit 1708 as necessary. Installed.

  When the above-described series of processing is realized by software, a program constituting the software is installed from a network such as the Internet or a storage medium such as a removable medium 1711.

  Such a storage medium is a removable medium 1711 in which a program is stored, as shown in FIG. 17, and is provided separately from the device to provide a program to the user. One skilled in the art should understand that is not limited. Examples of the removable medium 1711 include a magnetic disk (including a floppy disk), an optical disk (including a compact disk read-only memory (CD-ROM) and a digital versatile disk (DVD)), and a magneto-optical disk (mini disk (MD)). (Registered trademark)) and semiconductor memory. Alternatively, the storage medium may be a ROM 1702, a hard disk included in the memory unit 1708, or the like. Programs are stored in it and delivered to the user together with the devices containing them.

  The present invention further provides a program product in which machine-readable instruction codes are stored. When the instruction code is read and executed by a device, the method of performing synchronization detection in the communication system using the TDD mode according to the embodiment of the present invention can be executed. On the other hand, the enumerated storage media used for mounting such a program are also included in the disclosure of the present invention.

  In the above description of specific embodiments of the invention, the features described and / or illustrated for certain embodiments may be used in one or more other embodiments in the same or similar form, It can be combined with the features in the embodiments or can be substituted for the features in other embodiments.

  As used herein, the term “comprising / having” means the presence of a feature, element, step or component, but the presence or absence of one or more other features, elements, steps or components. Does not exclude additions. The terms “first”, “second”, etc. do not indicate the degree of implementation or importance of the features, elements, steps or components limited by these terminology, but these features are used for clarity of explanation. , Just a sign between elements, steps or components.

  In addition, the method of each embodiment of the present invention is not limited to being executed in the time order described in the specification or shown in the drawings, and may be executed in parallel or individually according to other time orders. Therefore, the execution order of the methods described herein does not limit the technical scope of the present invention.

The following appendices are further disclosed for the implementation means including the embodiments.
(Supplementary note 1) An apparatus for performing synchronization detection in a communication system in TDD mode,
With respect to the sample sequence for synchronization detection in the signal received by the device, each sample in the sample sequence is normalized based on the amplitude-related parameters of all samples in a predetermined range around the sample. Normalization means for performing normalization processing,
Synchronization detecting means for performing synchronization detection in accordance with the normalized sample sequence output by the normalizing means.
(Supplementary Note 2) The normalizing means is:
For each sample in the sample sequence, calculate an average value related to amplitude or a statistical value related to amplitude of all the samples in the predetermined range around the sample, and calculate the average value or statistical value corresponding to the sample. A normalization factor calculation sub-unit for outputting as a normalization factor;
Delay sub-means for delaying the sample sequence by a time corresponding to a certain proportion of the length of time in the predetermined range;
For each sample in the sample sequence, the delay sample corresponding to the sample output by the delay sub means is divided by the normalization factor corresponding to the sample output by the normalization factor calculation sub means. The apparatus according to claim 1, further comprising: a normalizing sub-unit that normalizes the sample.
(Supplementary Note 3) For each sample in the sample sequence, the normalization factor calculation sub-unit, the average value of the norm of the real part of all the samples in the predetermined range around the sample, the average value of the norm of the imaginary part The apparatus of claim 2, wherein the apparatus is configured to calculate a normalization factor corresponding to the sample via at least one of a value and an average value of a sum of a norm of a real part and a norm of a real part. .
(Supplementary note 4) The supplementary note 2 or 3, wherein the delay sub-unit is configured to delay the sample sequence by a time corresponding to half, 1/4, or 3/4 of the predetermined range of time length. The device described in 1.
(Supplementary Note 5) The normalization factor calculation sub-unit is:
In the initial stage of the normalization process, the first fixed value related to the performance of the sample or the device is used for the forward empty space of the sample to be normalized in the predetermined range around the sample to be normalized Filling, and calculating a normalization factor corresponding to the sample based on the filled predetermined range, and / or
At the end of the normalization process, the backward empty space of the sample to be normalized in the predetermined range around the sample to be normalized is used as a second fixed value related to the performance of the sample or the device. And calculating a normalization factor corresponding to the sample based on the filled predetermined range,
The apparatus of appendix 2 or 3 provided with the edge process part comprised as follows.
(Appendix 6) Further provided with control means,
The control means includes
When the device performs an initial cell search, the normalization unit is controlled to perform a normalization process until the synchronization detection unit detects an ID of a service cell that can provide a service to the device,
When the device performs an adjacent cell search at the same frequency in response to a command from the base station in the corresponding service cell, the normalization means includes two normalization means on the left and right of the synchronization signal of the service cell of the terminal device. Or control to perform the normalization process within a range of 2.5 subframes, and
When the apparatus performs an adjacent cell search for different frequencies in response to a command from the base station in the corresponding service cell, the normalization means performs an adjacent operation for each different frequency between the uplink signal and the downlink signal. The apparatus according to any one of appendices 1 to 3, wherein the apparatus is configured to control so as to execute a normalization process within a cell search section GAP.
(Appendix 7) The synchronization detection means includes:
By performing a correlation operation with the normalized sample sequence output by the normalization means using each of three known PSS sequences, the PSS sequence corresponding to the maximum correlation value or a correlation value higher than a certain threshold value The apparatus according to any one of appendices 1 to 3, further comprising primary synchronization signal PSS detection sub means configured to detect a PSS sequence corresponding to, and to detect a corresponding timing position.
(Supplementary Note 8) The synchronization detection means further includes:
Based on the output of the primary synchronization signal PSS detection means and the normalized sample sequence output by the normalization means, the CELL-ID of the cell that satisfies the request in the communication system in the TDD mode, and the type of the cyclic prefix CP And the secondary synchronization signal SSS detection sub means configured to detect the frame timing.
(Supplementary note 9) The apparatus according to any one of supplementary notes 1 to 8, wherein the communication system in the TDD mode is a TDD-LTE system or a TDD-LTEA system.
(Supplementary Note 10) A method for performing synchronization detection in a communication system in TDD mode,
With respect to a sample sequence for synchronization detection in a signal received by a terminal device that performs synchronization detection, each sample in the sample sequence is a parameter relating to the amplitude of all samples in a predetermined range around the sample. Perform normalization processing to normalize based on
Performing synchronization detection based on the normalized sample sequence obtained in the normalization process.
(Supplementary Note 11) The normalization process is as follows.
For each sample in the sample sequence, calculate an average value related to amplitude or a statistical value related to amplitude of all samples in the predetermined range around the sample, and the average value or statistical value is normalized to the sample Output as
Delaying the sample sequence by a time corresponding to a percentage of the predetermined range of time length;
For each sample in the sample sequence, the delayed sample corresponding to the sample output in the substep of delaying the sample sequence corresponds to the sample output in the substep of calculating the normalization factor. The method of claim 10, comprising normalizing the sample by dividing by a normalizing factor.
(Supplementary Note 12) The calculation of the normalization factor includes, for each sample in the sample sequence, an average value of a real part norm of all samples in the predetermined range around the sample, and a norm of an imaginary part The normalization factor corresponding to the sample is calculated through at least one of the average value of the average value and the average value of the sum of the norm of the real part and the norm of the imaginary part. Method.
(Supplementary note 13) The delaying of the sample sequence includes delaying the sample sequence by a time corresponding to half, 1/4, or 3/4 of the predetermined range of time length. The method according to 11 or 12.
(Supplementary note 14) The calculation of the normalization factor further includes
In the initial stage of the normalization process, the forward vacancy of the sample to be normalized in the predetermined range around the sample to be normalized is set as a first fixed value related to the performance of the sample or the terminal device. Use and fill, calculate a normalization factor corresponding to the sample based on the filled predetermined range, and / or
At the end stage of the normalization process, the backward empty of the sample to be normalized in the predetermined range around the sample to be normalized is set as a second fixed value related to the performance of the sample or the terminal device. Filling using and calculating a normalization factor corresponding to the sample based on the filled predetermined range;
The method of appendix 11 or 12 including this.
(Supplementary Note 15) When the terminal device performs an initial cell search, in the step of performing the synchronization detection, the normalization process is performed until an ID of a service cell that can provide a service to the terminal device is detected. Control and
When the terminal apparatus performs an adjacent cell search of the same frequency in response to a command from the base station in the corresponding service cell, the step of performing the normalization process includes the synchronization signal of the service cell of the terminal apparatus Control to perform the normalization process within a range of 2 or 2.5 subframes on the left and right of
When the terminal apparatus performs an adjacent cell search of a different frequency in response to a command from a base station in a corresponding service cell, the step of performing the normalization process is performed between an uplink signal and a downlink signal. Further comprising controlling to perform the normalization process within the interval GAP of the adjacent cell search of each different frequency.
The method according to any one of appendices 10 to 12.
(Supplementary Note 16) Performing the synchronization detection described above
A PSS sequence corresponding to the maximum value of the correlation value by performing a correlation operation with the normalized sample sequence output in the step of performing the normalization process using three known primary synchronization signal PSS sequences, Or detecting a PSS sequence corresponding to a correlation value higher than a certain threshold, and detecting a corresponding timing position.
(Supplementary Note 17) The above-described synchronization detection further includes
The communication system satisfies the requirements by performing the secondary synchronization signal SSS detection based on the detection result of the primary synchronization signal PSS detection and the normalized sample sequence output in the normalization processing step. 18. The method according to appendix 16, comprising detecting the cell CELL-ID, the type of cyclic prefix CP, and the frame timing.
(Additional remark 18) A terminal device provided with the apparatus which performs the synchronous detection as described in any one of additional marks 1-9.
(Additional remark 19) The program which performs the method of performing a synchronous detection in the communication system by TDD mode as described in any one of additional marks 10-17.
(Additional remark 20) The storage medium which memorize | stored the program which performs the method of performing a synchronous detection in the communication system by TDD mode as described in any one of additional marks 10-17.

While the invention has been disclosed by describing specific embodiments thereof, those skilled in the art can design various modifications, improvements or equivalents to the invention within the spirit and scope of the claims. . These modifications, improvements or equivalents should be recognized as being included within the protection scope of the present invention.

600 synchronization detection device 610 normalization means 620 motivation detection means 700 normalization means 710 delay sub means 720 normalization factor calculation sub means 730 normalization sub means 1100 synchronization detection device 1102 control means 1104 normalization means 1106 synchronization detection means 1200 synchronization detection Apparatus 1202 normalization means 1204 detection means 1212 PSS detection sub means 1300 synchronization detection apparatus 1302 normalization means 1304 detection means 1312 PSS detection sub means 1316 SSS detection sub means 1400 synchronization detection method 1410 start 1420 received by the terminal device that performs synchronization detection By performing normalization processing on the sample sequence for synchronization detection in the received signal, all samples in a predetermined range around the sample are detected for each sample in the sample sequence. Normalize the sample based on parameters related to the amplitude of 1430 Perform synchronization detection based on the normalized sample sequence 1440 End 1500 Synchronization detection method 1510 Start 1522 For each sample in the sample sequence, for each sample Calculate amplitude average or amplitude statistics of all samples in the surrounding predetermined range 1526 Delay sample sequence 1528 Divide delayed sample by corresponding normalization factor 1530 Based on normalized sample sequence Execute synchronization detection 1540 End 1700 Computing system 1701 CPU
1702 ROM
1703 RAM
1704 Bus 1705 Input / output interface 1706 Input unit 1707 Output unit 1708 Storage unit 1709 Communication unit 1710 Drive 1711 Removable medium

Claims (8)

An apparatus for performing synchronization detection in a wireless communication system,
With respect to the sample sequence for synchronization detection in the signal received by the device, each sample in the sample sequence is normalized based on the amplitude-related parameters of all samples in a predetermined range around the sample. Normalization means for performing normalization processing,
Synchronization detecting means for performing synchronization detection in accordance with the normalized sample sequence output by the normalizing means. The normalizing means includes
For each sample in the sample sequence, calculate an average value related to amplitude or a statistical value related to amplitude of all the samples in the predetermined range around the sample, and calculate the average value or statistical value corresponding to the sample. A normalization factor calculation sub-unit for outputting as a normalization factor;
Delay sub-means for delaying the sample sequence by a time corresponding to a certain proportion of the length of time in the predetermined range;
For each sample in the sample sequence, the delay sample corresponding to the sample output by the delay sub means is divided by the normalization factor corresponding to the sample output by the normalization factor calculation sub means. The apparatus according to claim 1, further comprising: normalization sub-unit for normalizing the sample.   The normalization factor calculation sub-unit, for each sample in the sample sequence, is the average value of the norm of the real part, the average value of the norm of the imaginary part, and the real value of all the samples in the predetermined range around the sample. The apparatus of claim 2, configured to calculate a normalization factor corresponding to the sample via at least one of an average value of a sum of a norm of a part and a norm of an imaginary part.   4. The delay sub-means are configured to delay the sample sequence by a time corresponding to half, 1/4, or 3/4 of the predetermined range of time length. apparatus. The normalization factor calculation sub-unit is:
In the initial stage of the normalization process, the first fixed value related to the performance of the sample or the device is used for the forward empty space of the sample to be normalized in the predetermined range around the sample to be normalized Filling, and calculating a normalization factor corresponding to the sample based on the filled predetermined range, and / or
At the end of the normalization process, the backward empty space of the sample to be normalized in the predetermined range around the sample to be normalized is used as a second fixed value related to the performance of the sample or the device. And calculating a normalization factor corresponding to the sample based on the filled predetermined range,
The apparatus of Claim 2 or 3 provided with the edge process part comprised as follows. Furthermore, a control means is provided,
The control means includes
When the device performs an initial cell search, the normalization unit is controlled to perform a normalization process until the synchronization detection unit detects an ID of a service cell that can provide a service to the device,
When the device performs an adjacent cell search at the same frequency in response to a command from the base station in the corresponding service cell, the normalization means includes two normalization means on the left and right of the synchronization signal of the service cell of the terminal device. Or control to perform the normalization process within a range of 2.5 subframes, and
When the apparatus performs an adjacent cell search for different frequencies in response to a command from the base station in the corresponding service cell, the normalization means performs an adjacent operation for each different frequency between the uplink signal and the downlink signal. The apparatus according to claim 1, wherein the apparatus is configured to perform control so as to perform a normalization process within a cell search section GAP. The synchronization detection means includes
By performing a correlation operation with the normalized sample sequence output by the normalization means using each of three known PSS sequences, the PSS sequence corresponding to the maximum correlation value or a correlation value higher than a certain threshold value 4. The apparatus according to claim 1, comprising primary synchronization signal PSS detection sub means configured to detect a PSS sequence corresponding to, and to detect a corresponding timing position. 5. A method for performing synchronization detection in a wireless communication system, comprising:
With respect to a sample sequence for synchronization detection in a signal received by a terminal device that performs synchronization detection, each sample in the sample sequence is a parameter relating to the amplitude of all samples in a predetermined range around the sample. Perform normalization processing to normalize based on
Performing synchronization detection based on the normalized sample sequence obtained in the normalization process.

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