WO2010016276A1 - Base station device, mobile station device, wireless communication system, and parameter acquisition method - Google Patents

Abstract

Disclosed is a base station device that communicates by two different wireless communication methods and that transmits, using the two wireless communication methods, a synchronization channel signal for one wireless communication method on the real axis and a synchronization channel signal for the other wireless communication method orthogonally modulated and disposed on the imaginary axis, thus enabling a mobile station device to determine the wireless communication method of the base station which is the transmission source using only the synchronization channel and without a deterioration of transmission efficiency.

Description

Base station apparatus, mobile station apparatus, radio communication system, and parameter acquisition method

The present invention relates to a base station device, a mobile station device, a wireless communication system, and a parameter acquisition method.
This application claims priority based on Japanese Patent Application No. 2008-206152 filed in Japan on August 8, 2008, the contents of which are incorporated herein by reference.

Wireless communication aimed at speeding up communication speed by introducing some of the technologies that have been studied for the 4th generation in the frequency band currently used in the 3rd generation mobile communication systems Evolved Universal Terrestrial Radio Access (3rd generation evolution, hereafter referred to as “EUTRA”), which is the system, is being studied by the standardization organization 3GPP (3rd Generation Partnership Project; 3rd Generation Partnership Project) (non-patent literature 1) ). EUTRA employs an OFDMA (Orthogonal Frequency Division Multiplexing Access) method that is resistant to multipath interference and suitable for high-speed transmission as a communication method.

In the cellular mobile communication system, since the mobile station needs to be wirelessly synchronized with the base station in advance in the cell or sector that is the communication area of the base station, the base station has a synchronization channel (Synchronization) having a predetermined configuration. (Channel; SCH) is transmitted, and the mobile station detects the synchronization channel SCH and synchronizes with the base station. When the mobile station detects the synchronization channel SCH and acquires information (parameters) on the cell, it is called cell search.
The cell search is classified into an initial cell search and a neighboring cell search. The initial cell search is a cell search that is performed in order for the mobile station to search for the nearest cell after the power is turned on and is located in that cell, and the neighboring cell search is a candidate cell to which the mobile station is a handover destination after the initial cell search. This is a cell search performed for searching.

FIG. 12 is a diagram illustrating an example of a configuration of a radio frame in EUTRA. In FIG. 12, the horizontal axis is the time axis, and the vertical axis is the frequency axis. A radio frame is configured with a frequency axis as 12 subcarriers (sc) and a time axis as a unit of a slot which is a set of a plurality of OFDM symbols, and an area divided by 12 subcarriers and 1 slot length is called a resource block. (Non-patent document 2). A group of two slots is called a subframe, and a group of ten subframes is called a frame.

The synchronization channel SCH includes a primary synchronization channel P-SCH (Primary Synchronization Channel) and a secondary synchronization channel S-SCH (S-SCH; Secondary Synchronization Channel; second synchronization channel). The positions of the primary synchronization channel P-SCH and the secondary synchronization channel S-SCH in EUTRA will be described.
As shown in FIG. 13, the primary synchronization channel P-SCH is arranged in the last OFDM symbol of the first slot of subframe numbers # 0 and # 5 in the 6 resource blocks at the center of the system bandwidth, and performs slot synchronization. Used to acquire part of cell information.
The secondary synchronization channel S-SCH is arranged on the OFDM symbol immediately before the primary synchronization channel P-SCH, and is used for frame synchronization with the rest of the cell information.
Note that in Non-Patent Document 2, the synchronization channel SCH is described as a synchronization signal, but the meaning is the same.

As shown in FIG. 14, in EUTRA, as a signal of the primary synchronization channel P-SCH, a code (Primary Synchronization Code) in which a part of the Zadoff-Chu sequence of length 63 (the 32nd value from the head) is indispensable is described below. , Referred to as “PSC”), 31 subcarriers on both sides sandwiching one subcarrier at the center of the system band are arranged on a total of 62 subcarriers. EUTRA prepares three Zadoff-Chu sequences used for PSC, and indicates part of the cell information depending on which sequence is used for PSC. Also, three scrambling codes to be multiplied by a secondary synchronization channel S-SCH, which will be described later, are prepared and associated with three PSCs, thereby reducing the identification error of the secondary synchronization channel S-SCH.

The secondary synchronization channel S-SCH uses two codes of length 31. An M code that is a binary code is used as an assigned code (SSC: Secondary Synchronization Code). As shown in FIG. 15, the subcarriers used in the SSC arrangement are a total of 62 subcarriers, with 31 subcarriers on both sides sandwiching one subcarrier at the center of the system band. Two 62 SSCs having a length of 31 (SSC1 and SSC2) are combined with these 62 subcarriers and arranged on the real axis. The mapping of SSC1 and SSC2 to the frequency axis takes an interleaved arrangement in which SSC1 and SSC2 are alternately arranged corresponding to the arranged subframe positions.

Specifically, the secondary synchronization channel S-SCH of subframe # 0 is alternately placed on the subcarriers in the order of SSC1 and SSC2, and at that time, SSC2 is multiplied by a scramble code corresponding to SSC1. The secondary synchronization channel S-SCH of subframe # 5 is alternately arranged on the subcarriers in the order of SSC2 and SSC1, and at that time, SSC1 is multiplied by a scramble code corresponding to SSC2.
In the mobile station apparatus, physical cell ID information is acquired from a combination of a PSC type (one of three types) and two types of SSCs (SSC1 and SSC2), and the frame timing (from the arrangement order of the two types of SSCs) The position of the subframe in the frame) can be acquired.

Next, FIG. 16 shows an example of the cell configuration. Each of the cells a, b, and c is composed of three sectors (sectors 1 to 3). Base stations a, b, and c in the center of each cell transmit radio waves having the frame structure to each sector of each cell. In FIG. 16, a case will be described where three orthogonal PSCs are used properly in three sectors in the same cell as described above. (The same PSC is used for sectors with the same sector number between different cells.)

The mobile station 1 that performs the initial cell search receives a signal transmitted from the base station a to the sector 2, a signal transmitted from the base station b to the sector 3, and a signal transmitted from the base station c to the sector 1. The mobile station 1 in the sector 2 of the cell a determines the correlation between the received signals and the replicas of the three types of primary synchronization channel P-SCH signals held in the own station, that is, the three types of PSCs, for a certain period. Observe and obtain the sector number (sector 2 in this case) and slot timing to be synchronized with the own station from the time when the correlation peak becomes maximum and the type of PSC (step 1).

Next, the mobile station 1 performs propagation path estimation from the difference between the replica having the maximum correlation peak, that is, the replica of the primary synchronization channel P-SCH signal in sector 2 and the received primary synchronization channel P-SCH signal. Do. Further, the position of the secondary synchronization channel S-SCH is identified from the acquired slot timing, and the signal of the secondary synchronization channel S-SCH is propagated using the propagation path estimation result of the primary synchronization channel P-SCH described above. Perform road compensation. Then, descrambling processing is performed on the signal of the secondary synchronization channel S-SCH subjected to propagation path compensation. The secondary synchronization channel S-SCH is multiplied by a scramble code corresponding to the type (three types) of PSC, and the scramble is released.
Next, by performing correlation processing (for the scrambled signal on the transmission side) for all combinations of SSC1 and SSC2, the combination and arrangement order of SSC1 and SSC2 are identified, and information for identifying a base station from the combination is obtained. The acquired physical cell ID is identified by the sector number acquired by the primary synchronization channel P-SCH and the information for identifying the base station. Also, frame timing is acquired from the arrangement order (step 2).
By performing the processing of Step 1 and Step 2 described above, cell search can be performed in two steps.
In the above description, the PSC number corresponds to the sector number. However, the present invention is not limited to this, and the PSC number only needs to represent a part of the physical cell ID. A sector may be used as a communication range, and the same PSC number may be used for a plurality of sectors, and a signal generated using a different SSC number for each sector may be transmitted.

As for the neighboring cell search, the processing of step 2 is performed for the remaining two PSCs that did not take the maximum value in the correlation observation in step 1 in the above procedure, and the physical cell ID and frame timing are acquired. Thus, the surrounding cells are detected. When the received power of the connected cell decreases, the mobile station performs a neighbor cell search and measures the received power of the detected downlink reference signal (unique code corresponding to the physical cell ID) of each cell. To do. The mobile station notifies the base station apparatus of the connected cell of the measurement result, and the base station performs handover of the mobile station based on the reported power information of the cell, access restriction information of the cell, etc. Determine the destination.

Further, 3GPP is also studying Advanced-EUTRA (a development of the third generation evolution), which is a wireless communication system developed from EUTRA as a fourth generation communication technology. In Advanced-EUTRA, since the EUTRA mobile station can access the Advanced-EUTRA base station, that is, backward compatibility is required, resources that can be used by the EUTRA mobile station by means of frequency division or time division. It has been considered to ensure. In this case, the Advanced-EUTRA base station is directed to the EUTRA mobile station for the EUTRA primary synchronization channel so that the EUTRA mobile station can perform cell search and synchronize with the Advanced-EUTRA base station. It is necessary to arrange the P-SCH and the secondary synchronization channel S-SCH. Further, it has been proposed to arrange a dedicated synchronization channel different from the primary synchronization channel P-SCH and secondary synchronization channel S-SCH of EUTRA for the mobile station of Advanced-EUTRA (Non-patent Document 3). ).

However, as proposed in Non-Patent Document 3, in the method of separately arranging a dedicated synchronization channel for an Advanced-EUTRA mobile station, synchronization channels of two wireless communication schemes, Advanced-EUTRA and EUTRA, are provided. Therefore, there is a problem that the bandwidth is compressed by these synchronization channels and the transmission efficiency is deteriorated.
Also, the synchronization channel for EUTRA mobile stations is commonly used in two wireless communication systems, Advanced-EUTRA and EUTRA, and which wireless communication system is the base station through the broadcast channel, not the synchronization channel It is also conceivable to notify the mobile station. However, in such a method, the mobile station cannot determine which wireless communication system is the base station without acquiring the broadcast channel during the peripheral cell search. There is.

The present invention has been made in view of such circumstances, and its purpose is to determine which wireless communication system the base station of the transmission source is based on only the synchronization channel without degrading the transmission efficiency. It is an object of the present invention to provide a base station device, a mobile station device, a wireless communication system, and a parameter acquisition method that can be determined by the mobile station device.

(1) A base station apparatus according to the present invention is a base station apparatus that communicates in two different wireless communication systems, and transmits a synchronization channel signal representing a parameter of one of the two wireless communication systems. A signal obtained by arranging the synchronization channel signal representing the parameters of the real axis and the other wireless communication system on the imaginary axis and performing quadrature modulation is arranged on the synchronization channel and transmitted.

(2) Moreover, the base station apparatus of this invention is the above-mentioned base station apparatus, Comprising: The signal arrange | positioned to a synchronous channel includes the 1st synchronizing signal for taking time synchronization, the said base station apparatus, And a second synchronization signal that specifies a parameter for communication, and the signal of the synchronization channel that is orthogonally modulated is the second synchronization signal.

(3) Further, the base station apparatus of the present invention is the above-described base station apparatus, wherein the code sequence of the signal arranged on the real axis and the code sequence of the signal arranged on the imaginary axis are low-correlation sequences. It is characterized by being.

(4) Moreover, the base station apparatus of the present invention is the above-described base station apparatus, wherein the code sequence of the signal arranged on the real axis and the code sequence of the signal arranged on the imaginary axis are part of the sequence. Are the same, and the remaining part of the sequence is a sequence having a low correlation with each other.

(5) Further, the base station apparatus of the present invention is the above-described base station apparatus, wherein the code sequence of the signal arranged on the imaginary axis is obtained by multiplying the code sequence of the signal arranged on the real axis by a predetermined code. It is characterized by being a series.

(6) Moreover, the base station apparatus of this invention is the above-mentioned base station apparatus, The code sequence of the signal arrange | positioned to the said imaginary axis is the said code sequence candidate of the signal arrange | positioned to the said real axis. It is a sequence obtained by multiplying a code sequence corresponding to a parameter of the other wireless communication system by a predetermined code.

(7) Moreover, the base station apparatus of the present invention is the above-described base station apparatus, wherein the two wireless communication schemes have at least a part of the parameters as a common value, It transmits by the signal arrange | positioned to a real axis.

(8) Moreover, the base station apparatus of this invention is the above-mentioned base station apparatus, Comprising: The parameter with the said common value is the information which identifies a base station apparatus.

(9) Further, the mobile station apparatus of the present invention includes a receiving unit that receives a synchronization channel transmitted from a base station apparatus, and a received synchronization channel signal that is a real-axis signal and an imaginary-axis signal. A complex signal separation unit that separates a signal into an imaginary part signal, and parameters represented by each of the real part signal and the imaginary part signal, and parameters of a wireless communication method used by the mobile station device for communication are acquired. And a parameter acquisition unit.

(10) Further, the wireless communication system of the present invention includes a base station device that communicates using two different wireless communication methods, and the base station device that uses at least one wireless communication method of the two wireless communication methods. A wireless communication system comprising a mobile station device for communication, wherein the base station device uses a synchronization channel signal representing a parameter of one of the two wireless communication methods as a real axis, and the other wireless communication method. A signal obtained by arranging a synchronization channel signal representing a communication method parameter on the imaginary axis and orthogonally modulating the signal is arranged on the synchronization channel and transmitted, and the mobile station apparatus receives the synchronization channel and the reception unit. A complex signal separation unit that separates a synchronization channel signal into a real part signal that is a real axis signal and an imaginary part signal that is an imaginary axis signal, and parameters represented by each of the real part signal and the imaginary part signal. Of data, characterized by comprising a parameter acquisition section that the mobile station apparatus acquires the parameters of a wireless communication system using in the communication.

(11) Further, the parameter acquisition method of the present invention includes a base station device that communicates with two different wireless communication methods, and the base station device that uses at least one wireless communication method of the two wireless communication methods. A parameter acquisition method in a wireless communication system including a mobile station device for communication, wherein the base station device uses a real channel for a synchronization channel signal representing a parameter of one of the two wireless communication methods. A first step of transmitting a signal obtained by arranging a synchronization channel signal representing a parameter of the other wireless communication system on the imaginary axis and performing orthogonal modulation on the synchronization channel, and transmitting the synchronization channel signal to the synchronization channel. And a synchronization channel signal received by the mobile station apparatus in the first step, a real part signal that is a real axis signal and an imaginary axis signal that is an imaginary axis signal. Among the parameters represented by each of the real part signal and the imaginary part signal, and a parameter of a radio communication scheme used by the mobile station apparatus for communication, And a fourth process to be acquired.

According to the present invention, the base station apparatus performs quadrature modulation by arranging a synchronization channel signal representing one radio communication system parameter on the real axis and a synchronization channel signal representing the other radio communication system parameter on the imaginary axis. The mobile station apparatus determines which radio communication system the base station of the transmission source is based on only the synchronization channel without degrading the transmission efficiency. be able to.

It is a schematic block diagram which shows the structure of the base station apparatus 1 by 1st Embodiment of this invention. It is a schematic block diagram which shows the internal structure of the synchronizing signal generation part 132 in the embodiment. It is a schematic block diagram which shows the structure of the mobile station apparatus 2 in the embodiment. It is a schematic block diagram which shows the structure of the synchronizer 23 in the embodiment. It is a schematic block diagram which shows the structure of the demodulation / decoding part 28 in the embodiment. 3 is a schematic block diagram showing a configuration of an S-SCH demodulator / decoder 283 in the same embodiment. FIG. It is a schematic block diagram which shows the structure of the synchronizing signal generation part 132a of the base station apparatus 1a in 2nd Embodiment of this invention. FIG. 3 is a schematic block diagram showing a configuration of an S-SCH demodulation / decoding unit 283a of the mobile station device 2a in the same embodiment. It is a schematic block diagram which shows the structure of the synchronizing signal generation part 132b of the base station apparatus 1b in 3rd Embodiment of this invention. FIG. 4 is a schematic block diagram showing a configuration of an S-SCH demodulation / decoding unit 283b of the mobile station device 2b in the same embodiment. It is a schematic block diagram which shows the structure of the correlation part 292b in the same embodiment. It is a figure which shows an example of the structure of the radio | wireless frame in the conventional EUTRA. FIG. 7 is a diagram illustrating an arrangement of a primary synchronization channel P-SCH and a secondary synchronization channel S-SCH in conventional EUTRA. FIG. 6 is a diagram showing an arrangement of primary synchronization channels P-SCH in conventional EUTRA. It is a figure which shows arrangement | positioning of the secondary synchronization channel S-SCH in the conventional EUTRA. It is a figure which shows an example of the cell structure in the conventional EUTRA.

(First embodiment)
Hereinafter, a first embodiment of the present invention will be described with reference to the drawings. The radio communication system according to the first embodiment of the present invention uses a base station apparatus 1 that communicates in two different radio communication schemes (in this embodiment, EUTRA and Advanced-EUTRA), and Advanced-EUTRA as the radio communication scheme. Mobile station apparatus 2 communicating with each other. From a state where a communication service provider provides a communication service by EUTRA using a base station device that communicates with EUTRA, and a communication service user owns a mobile station device of EUTRA and enjoys a communication service by EUTRA, In the process in which the communication service provider replaces the EUTRA base station device with the base station device 1 which is an advanced-EUTRA base station device, the communication service provider provides the EUTRA communication service and newly provides the Advanced-EUTRA communication service. Is done.

For this reason, the advanced-EUTRA base station apparatus 1 is recognized as an EUTRA base station apparatus by the existing EUTRA mobile station apparatus, provides a communication service by EUTRA, and the advanced-EUTRA mobile station apparatus 2 provides an advanced service. -It is necessary to be recognized as a base station apparatus 1 of EUTRA and to be able to provide a communication service by Advanced-EUTRA.

FIG. 1 is a schematic block diagram showing the configuration of the base station apparatus 1 in the present embodiment. As shown in FIG. 1, the base station apparatus 1 includes a control unit 10, a reception unit 12, and a transmission unit 13, and a reception antenna unit 11 that receives radio waves from each mobile station device 2 is connected to the reception unit 12. The transmitting unit 13 is connected to a transmitting antenna unit 14 for transmitting radio waves to each mobile station device 2.
The base station apparatus 1 uses the secondary synchronization channel S-SCH signal indicating parameters of one of the two wireless communication systems (EUTRA) as a real axis and the other wireless communication system (Advanced-EUTRA). A signal obtained by arranging the signal of the secondary synchronization channel S-SCH representing the parameter on the imaginary axis and performing quadrature modulation is arranged on the secondary synchronization channel S-SCH and transmitted. The parameters include a physical cell ID that is information for identifying the base station apparatus, a subframe number indicating a position in a frame of the subframe in which the synchronization channel SCH is arranged, and the like.

The control unit 10 controls the reception unit 12 and the transmission unit 13. Regarding transmission of the synchronization channel SCH by the transmission unit 13, the control unit 10 determines a PSC number (details will be described later) based on a transmission target sector, and a physical cell ID and a sector, which are information for identifying the base station apparatus 1. SSC number (details will be described later) is determined, and in addition to the PSC number and the SSC number, the subframe number indicating the position in the frame of the subframe in which the synchronization channel SCH is arranged is notified to the transmission unit 13 To do. The receiving unit 12 receives a signal from the mobile station apparatus 2 via the receiving antenna unit 11, and outputs data detected from the signal to the outside. The transmission unit 13 generates a transmission signal of data to the mobile station apparatus 2 input from the outside, and transmits it via the transmission antenna unit 14.
The reception unit 12 includes a reception analog circuit unit 120, an A / D (Analogue / Digital) conversion unit 121, and a demodulation processing unit 122. The reception analog circuit unit 120 outputs an analog signal obtained by converting a signal received via the reception antenna unit 11 into a frequency that can be demodulated. The A / D conversion unit 121 converts the analog signal processed by the reception analog circuit unit 120 into a digital signal. The demodulation processing unit 122 demodulates the digital signal converted by the A / D conversion unit 121 and outputs the detected data to the outside.

The transmission unit 13 includes a data modulation unit 130, a control signal modulation unit 131, a synchronization signal generation unit 132, a multiplexing / modulation processing unit 133, a D / A (Digital / Analogue) conversion unit 134, and a transmission analog circuit unit 135. The data modulation unit 130 modulates transmission data (including broadcast information) to the mobile station apparatus 2 input from the outside, and generates a data signal. The control signal modulation unit 131 modulates control information for the mobile station apparatus 2 and generates a control signal. The synchronization signal generation unit 132 generates a synchronization signal that is a signal of a synchronization channel. The synchronization channel includes a primary synchronization channel P-SCH and a secondary synchronization channel S-SCH. Therefore, a signal arranged in the synchronization channel SCH includes a primary synchronization channel P-SCH for time synchronization. Including a signal (first synchronization signal) and a signal (second synchronization signal) of a secondary synchronization channel S-SCH that specifies parameters for communication with the base station apparatus 1 and is orthogonally modulated. The signal of channel SCH is the signal of secondary synchronization channel S-SCH among these. The multiplexing / modulation processing unit 133 performs multiplexing / modulation processing on the synchronization signal, the control signal, and the data signal as frames to be transmitted. The D / A conversion unit 134 converts the frame signal modulated by the multiplexing / modulation processing unit 133 into an analog signal. The transmission analog circuit unit 135 converts the D / A converted analog signal into a frequency necessary for transmission, and transmits the frequency via the transmission antenna unit 14.

FIG. 2 is a schematic block diagram illustrating the internal configuration of the synchronization signal generation unit 132. The synchronization signal generation unit 132 includes a PSC1 holding unit 1320, a PSC2 holding unit 1321, a PSC3 holding unit 1322, a selector 1323, a first code holding unit 1324, a first code selection unit 1325, a second code holding unit 1326, 2 code selector 1327 and quadrature modulator 1328. The orthogonal modulation unit 1328 includes a multiplication unit 1329, a multiplication unit 1330, and an addition unit 1331.

The PSC1 holding unit 1320 holds the first code (hereinafter referred to as “code PSC1”) out of the three codes of length 62 used for the primary synchronization channel P-SCH of EUTRA.
PSC2 holding section 1321 holds the second code (hereinafter referred to as “code PSC2”) out of the three codes of length 62 used for EUTRA primary synchronization channel P-SCH. PSC3 holding section 1322 holds the third code (hereinafter referred to as “code PSC3”) out of the three codes of length 62 used for EUTRA primary synchronization channel P-SCH. The selector 1323 selects a code according to the PSC number designated by the control unit 10 from the codes PSC1, PSC2, and PSC3 held by the PSC1 holding unit 1320, the PSC2 holding unit 1321, and the PSC3 holding unit 1322, and outputs the selected code. . In the present embodiment, a cell that is a communication range of one base where the base station apparatus 1 is installed is divided into three sectors, and PSC numbers 1 to 3 are associated with these three sectors. . In this embodiment, the association between these three sectors and the PSC numbers 1 to 3 is the same in EUTRA and Advanced-EUTRA.
Further, in the present embodiment, the PSC number is associated with the sector. However, the present invention is not limited to this, and the PSC number only needs to represent a part of the physical cell ID. A sector may be used as a communication range, and the same PSC number may be used for a plurality of sectors, and a signal generated using a different SSC number for each sector may be transmitted.

Further, the first code selection unit 1325 uses the code SSC of length 62 used for the secondary synchronization channel S-SCH of EUTRA based on the SSC number, the PSC number, and the subframe number designated by the control unit 10. Is read from the first code holding unit 1324 and output to the multiplication unit 1329. The first code holding unit 1324 performs arrangement (including interleaving) of code SSC1 and code SSC2 of length 31 corresponding to the SSC number, corresponding to each subframe number (# 0, # 5). A code of length 62 is generated, and a code SSC of length 62 obtained by multiplying the scramble code corresponding to the PSC number is held. That is, when there are 168 types of SSC numbers, there are two types of subframe positions, # 0 or # 5, and there are three types of PSC numbers. Therefore, the first code holding unit 1324 has 168 × 2 × 3 = 1008 types. Hold series.

In this embodiment, since the SSC number is considered to be changed, the first code holding unit 1324 holds all combinations. However, when the SSC number is fixed or several types In the case of only candidates, the necessary number of candidates may be held, or only one type (or three types according to the type of PSC number) is held, and when the SSC number is changed The stored series may be updated.
The multiplication unit 1329 multiplies the code SSC output from the first code selection unit 1325 by “1” and outputs the result as a sequence 1. Further, the adding unit 1331 adds up the series 1 and the series 2 described later, and outputs the result as the series 3. Here, the multiplication unit 1329 multiplying the code SSC by “1” indicates that each value of the code SSC is multiplied by “1”. For example, when the code SSC is “1, −1,... −1, −1”, by multiplying this by “1”, “1 × 1 = 1, 1 × −1. −1, 1 × −1 = −1 ”.

Also, an Advanced SSC number corresponding to Advanced-EUTRA information (parameters) is input from the control unit 10 to the second code selection unit 1327. The Advanced-EUTRA information includes information to be acquired by the mobile station apparatus 2 during the initial cell search and the neighboring cell search, such as cell frequency band information, the number of antennas used, and the cell type. May be.

The second code selection unit 1327 reads the code Advanced SSC having a length of 62 corresponding to the Advanced SSC number designated by the control unit 10 from the second code holding unit 1326 and outputs the read code to the multiplication unit 1330. Here, the code Advanced SSC stored in the second code holding unit 1326 has been described as a code of length 62 corresponding to the Advanced SSC number, but the code SSC held by the first code holding unit 1324 is described. Similarly to the above, in addition to the Advanced SSC number, a code corresponding to each subframe number or three types of PSC numbers may be held. That is, the second code selection unit 1327 may output a code corresponding to the subframe number and the PSC number as well as the Advanced SSC number, similarly to the EUTRA code SSC.

The multiplication unit 1330 multiplies the code Advanced SSC output from the second code selection unit 1327 by the imaginary unit j. That is, the series 3 in which the adding unit 1331 adds the series 1 and the series 2 is a complex series. Here, the multiplication unit 1330 multiplying the code Advanced SSC and the imaginary unit j indicates that each value of the code Advanced SSC is multiplied by “j”. For example, when the code Advanced SSC is “1, −1,... −1, −1”, when this is multiplied by “j”, “1 × j = j, −1 × j = −j · ... −1 × j = −j, −1 × j = −j ”.

In this way, the code PSC and the sequence 3 generated by the synchronization signal generation unit 132 are processed by the multiplexing / modulation processing unit 133 so that each value of the code PSC is the primary synchronization channel P-SCH of EUTRA, and each value of the sequence 3 is EUTRA. Of the secondary synchronization channel S-SCH. Here, each value of the code PSC or the sequence 3 is arranged, for example, if the code PSC is “1, −1,...”, The signal “1”, that is, the phase is “0” and the amplitude is “0”. 1 ”signal is arranged on the first subcarrier of the primary synchronization channel P-SCH, and the signal“ −1 ”, that is, the signal with phase“ π ”and amplitude“ 1 ”is assigned to the second subcarrier. Represents placement on a carrier. In the case of series 3, each value takes one of the four values “1 + j”, “1-j”, “−1 + j”, and “−1−j”, so that the phase is “π / 4”. ”,“ 3π / 4 ”,“ 5π / 4 ”,“ 7π / 4 ”, and a signal having an amplitude of √2 (square root of 2) is arranged.

Note that the primary synchronization channel P-SCH is arranged in the last OFDM symbol of the first slot of subframe numbers # 0 and # 5, and is 6 in the center of the system bandwidth, and 2 in the immediately preceding OFDM symbol. A next synchronization channel S-SCH is arranged. Since code PSC and sequence 3 are sequences of length 62, both sides of the above-described primary synchronization channel P-SCH and secondary synchronization channel S-SCH except for the subcarrier at the center of the system bandwidth. Each of the 31 subcarriers is arranged.

Next, the mobile station apparatus 2 will be described. FIG. 3 is a schematic block diagram showing the configuration of the mobile station apparatus 2 in the present embodiment. As shown in FIG. 3, the mobile station apparatus 2 includes a reception analog circuit unit 21, an A / D conversion unit 22, a synchronization unit 23, a GI removal unit 24, and an S / P (Serial to Parallel) conversion unit 25. , FFT (Fast Fourier Transform) unit 26, propagation path estimation / compensation unit 27, demodulation / decoding unit 28, MAC (Media Access Control; media access control) unit 29, modulation unit 30, IFFT (Inverse Fast Fourier) A transform (inverse fast Fourier transform) 31, a P / S (Parallel to Serial) conversion unit 32, a GI addition unit 33, a D / A conversion unit 34, and a transmission analog circuit unit 35 are provided. Further, the reception antenna unit 20 is connected to the reception analog circuit unit 21, and the transmission antenna unit 36 is connected to the transmission analog circuit unit 35.

The reception analog circuit unit (reception unit) 21 receives a signal transmitted from the base station apparatus 1 including the primary synchronization channel P-SCH and the secondary synchronization channel S-SCH via the reception antenna unit 20, and receives the signals. The converted analog signal is converted into a signal having a frequency that can be demodulated. The A / D conversion unit 22 converts the analog signal processed by the reception analog circuit unit 21 into a digital signal. The synchronization unit 23 performs time synchronization with the base station apparatus 1 and sector identification based on the received digital signal. The GI removal unit 24 removes a guard interval determined based on time synchronization by the synchronization unit 23. The S / P converter 25 converts the serial signal from which the guard interval is removed into a parallel signal.

The FFT unit 26 converts the time domain signal converted into the parallel signal into a frequency domain signal by performing a fast Fourier transform. The propagation path estimation / compensation unit 27 selects a signal to be used for propagation path estimation from the signal converted to the frequency domain and estimates the propagation path. Based on the propagation path estimation result, the propagation path compensation is performed on the frequency domain signal. I do. The demodulator / decoder 28 demodulates and decodes a control signal, a data signal, a secondary synchronization channel S-SCH signal, etc. in the propagation path compensated signal. The MAC unit 29 controls each unit of the mobile station device 2. For example, the MAC unit 29 receives the demodulated and decoded data signal, control signal, and secondary synchronization channel S-SCH signal from the demodulation / decoding unit 28, and outputs the data signal to the outside. Further, the MAC unit 29 generates control information according to the demodulation / decoding result of the control signal and the secondary synchronization channel S-SCH signal, and sends the control information to the modulation unit 30 together with the data to the base station apparatus 1 inputted from the outside. Output.

The modulation unit 30 modulates data and control information to the base station apparatus 1 received from the MAC unit 29, and generates a data signal and a control signal that are frequency domain signals. The IFFT unit 31 converts the modulated frequency domain signal into a time domain signal. The P / S converter 32 converts the time domain parallel signal converted by the IFFT unit 31 into a serial signal. The GI adding unit 33 adds a guard interval to the P / S converted signal. The D / A converter 34 converts the digital signal to which the guard interval is added into an analog signal. The transmission analog circuit unit 35 converts the analog signal that has been D / A converted into a frequency necessary for transmission, and transmits the analog signal to the base station apparatus 1 via the transmission antenna unit 36.

FIG. 4 is a schematic block diagram illustrating the configuration of the synchronization unit 23. The synchronization unit 23 includes a first correlator 230, a second correlator 231, a third correlator 232, a first buffer 233, a second buffer 234, a third buffer 235, and a sector timing detector 236. The first correlator 230, the second correlator 231, and the third correlator 232 hold one corresponding replica of the three types of code PSCs in advance, and obtain a correlation between the replica and the received signal. The first buffer 233, the second buffer 234, and the third buffer 235 respectively hold the correlation results of the corresponding correlators 230 to 232 for a certain period. The sector timing detector 236 detects the type and timing of the code PSC to be synchronized from the correlation results held in the buffers 233 to 235.

FIG. 5 is a schematic block diagram showing the configuration of the demodulator / decoder 28. The demodulation / decoding unit 28 includes an input selector 280, a control signal demodulation / decoding unit 281, a plurality of data signal demodulation / decoding units 282, an S-SCH demodulation / decoding unit 283, and an output selector 284. The input selector 280 receives a received signal that has been subjected to propagation path compensation from the propagation path estimation / compensation unit 27, and performs demodulation / decoding processing on the control signal according to the type of the received signal. The received signal is distributed to the data signal demodulation / decoding unit 282 that performs demodulation / decoding processing on the S-SCH demodulation / decoding unit 283 that performs demodulation processing on the signal of the secondary synchronization channel S-SCH. The output selector 284 acquires the demodulation / decoding processing result by switching according to the type of the received signal from each unit to which the input selector 280 has distributed the received signal, and outputs the result to the MAC unit 29.

FIG. 6 is a schematic block diagram showing the configuration of the S-SCH demodulator / decoder 283. As shown in FIG. 6, the S-SCH demodulation / decoding unit 283 includes a complex signal separation unit 290, a first replica holding unit 291, a real part correlation unit 292, a first SSC identification unit 293, and a second replica holding unit. 294, an imaginary part correlation unit 295, and a second SSC identification unit 296. The complex signal separation unit 290 converts the complex signal (secondary synchronization channel S-SCH signal) input from the input selector 280 into a real part signal that is a real axis signal and an imaginary part signal that is an imaginary axis signal. To separate. For example, if the complex signal is “a1 + b1j, a2 + b2j, a3 + b3j,...”, The real part signal “a1, a2, a3,...” And the imaginary part signal “b1, b2, b3,. To separate.

The first replica holding unit 291 holds all EUTRA code SSC replicas. The real part correlation unit 292 correlates the real part signal output from the complex signal separation unit 290 with all code SSC replicas corresponding to the PSC numbers input from the synchronization unit 23 to the first replica holding unit 291. Process. The first SSC identification unit 293 identifies the replica having the maximum correlation among all the replicas subjected to the correlation processing by the real part correlation unit 292, and the SSC number and subframe number corresponding to the replica, that is, EUTRA. The SSC number and the subframe number are identified.

The second replica holding unit 294 holds all the codes Advanced SSC replicas. The imaginary part correlation unit 295 performs correlation processing between the imaginary part signal output from the complex signal separation unit 290 and all replicas held by the second replica holding unit 294. The second SSC identification unit 296 identifies the replica having the maximum correlation among the replicas that the imaginary part correlation unit 295 has performed correlation processing, and compares the correlation value with a predetermined threshold value. When the correlation value is less than the threshold value as a result of this comparison, the second SSC identification unit 296 does not detect the Advanced-EUTRA secondary synchronization channel S-SCH, and the cell of the sector can communicate only with EUTRA. It is determined that the cell is an EUTRA cell. The second SSC identification unit 296 determines that the Advanced-EUTRA secondary synchronization channel S-SCH is greater when the correlation value is the same as the predetermined threshold or larger than the predetermined threshold as a result of the previous comparison. The detected cell of the sector is determined to be an Advanced-EUTRA cell communicable by Advanced-EUTRA, and the Advanced SSC number corresponding to the replica having the maximum correlation is identified.

Thus, in the present embodiment, the first SSC identification unit 293 and the second SSC identification unit 296 function as parameter acquisition units, and are EUTRA parameters that are represented by each of the real part signal and the imaginary part signal. The SSC number, subframe number, and advanced SSC number are acquired. In this embodiment, all parameters represented by the real part signal and the imaginary part signal are acquired. However, only the parameters of the radio communication scheme used by the mobile station apparatus for communication may be acquired. .

The cell search procedure by the mobile station device 2 will be described. In the mobile station apparatus 2 that has received the signal including the primary synchronization channel P-SCH and the secondary synchronization channel S-SCH transmitted from the base station apparatus 1, the synchronization unit 23 uses the received signal after A / D conversion. Detects the primary synchronization channel P-SCH and acquires the synchronization timing and sector information (PSC number). Furthermore, the mobile station apparatus 2 removes the guard interval from the received signal based on the detected synchronization timing, undergoes S / P conversion, and then performs fast Fourier transform processing to convert the signal from the time domain to the frequency domain.

The propagation path estimation / compensation unit 27 of the mobile station apparatus 2 performs the phase between the primary synchronization channel P-SCH signal in the received signal converted into the frequency domain and the known primary synchronization channel P-SCH replica. • Perform propagation path estimation by looking at the amplitude difference, and obtain propagation path estimation values. Subsequently, the propagation path estimation / compensation unit 27 performs propagation path compensation on the secondary synchronization channel S-SCH signal in the received signal converted to the frequency domain, using this propagation path estimated value. The input selector 280 of the demodulation / decoding unit 28 inputs the signal of the secondary synchronization channel S-SCH in the frequency domain that has undergone propagation path compensation to the S-SCH demodulation / decoding unit 283.

The complex signal separation unit 290 separates the received signal input to the S-SCH demodulation / decoding unit 283 into a real part and an imaginary part, and inputs the real part and the imaginary part correlation unit 295. The real part correlation unit 292 that has received the real part performs correlation processing between the replica corresponding to the PSC number received from the synchronization unit 23 among the replicas held by the first replica holding unit 291 and the received real part. . The imaginary part correlation unit 295 that has received the imaginary part performs correlation processing between all replicas held by the second replica holding unit 294 and the received imaginary part. Thereafter, the first SSC identification unit 293 identifies the SSC number and the subframe number, and the second SSC identification unit 296 includes information indicating whether the cell of the base station apparatus that has transmitted the received signal is an Advanced-EUTRA cell. And Advanced-EUTRA, the Advanced SSC number is identified. If it is not an Advanced-EUTRA cell, the Advanced SSC number becomes invalid and is discarded.

The information corresponding to the Advanced SSC number, that is, the Advanced-EUTRA parameters include cell ID dedicated to Advanced-EUTRA, cell frequency band information, transmission antenna information, etc., but communication is performed using Advanced-EUTRA. In this case, at least a part of parameters common to Advanced-EUTRA and EUTRA (for example, physical cell ID) is a common value, and a parameter having a common value is not necessarily included. You may make it transmit with a SSC number, ie, the signal arrange | positioned to a real axis.

In the present embodiment, all replicas for correlation processing are held in the second replica holding unit 294. However, replicas may be calculated and used every time correlation processing is performed.
Further, the code Advanced SSC may be a combination of a plurality of types of binary codes as in the case of the EUTRA code SSC, or may be a single type of code. Further, as the code advanced SSC scrambling, a code corresponding to the PSC number may be multiplied, or a scrambling code corresponding to the EUTRA code SSC may be multiplied.

However, it is desirable that the code used for the code Advanced SSC is a sequence different from the code used for the EUTRA code SSC (a sequence with low correlation). For example, a code whose correlation value with the EUTRA code SSC is smaller than the threshold value compared with the correlation value calculated by the imaginary part correlation unit 295 in the second SSC identification unit 296, that is, a code with a low correlation is encoded Used for Advanced SSC.

When channel compensation of the secondary synchronization channel S-SCH by the primary synchronization channel P-SCH cannot be performed accurately, the signal of the secondary synchronization channel S-SCH is converted into a real part (EUTRA code SSC) and an imaginary part (Advanced- It is impossible to accurately separate the EUTRA code Advanced SSC). Then, when calculating the correlation value for the EUTRA code SSC, the signal of the Advanced-EUTRA code Advanced SSC is also included, and vice versa. However, by setting the code Advanced SSC as described above, it is possible to suppress the influence on the correlation value and prevent the occurrence of identification errors in the first SSC identification unit 293 and the second SSC identification unit 296.

Here, as an example of a code used in the Advanced-EUTRA code Advanced SSC, a sequence that is a M-sequence preferred pair of length 31 used in EUTRA (a sequence in which the value of the cross-correlation takes only a fixed ternary value) is used. It can be used.
Further, in Advanced-EUTRA, when using the Advanced SSC having the same structure as EUTRA composed of SSC1 and SSC2, either one of SSC1 and SSC2 (for example, SSC1) is set as the same signal as EUTRA. The remaining sequence (for example, SSC2) is an M sequence that is not used in EUTRA, or an M sequence that is the preferred pair, that is, a signal sequence that is arranged on the real axis and a signal that is arranged on the imaginary axis. These code sequences may be the same for a part of the sequence, and the remaining portions of the sequence may be sequences having a low correlation with each other. Here, the low correlation is the same as the low correlation in the relationship between the code used for the above-mentioned code Advanced SSC and the code used for the EUTRA code SSC.

According to the present embodiment, the mobile station device 2 can communicate with the advanced base station in the advanced-EUTRA without using dedicated frequency resources and without affecting the operation of the existing EUTRA mobile station device. It is possible to arrange synchronization channels that can be identified. Since no dedicated frequency resource is required, the transmission efficiency is not deteriorated, and Advanced-EUTRA can be identified using only the synchronization channel. For this reason, when performing measurement of neighboring cells in the communication state of the Advanced-EUTRA mobile station apparatus 2, a desired communication is performed such as preferentially measuring and reporting the cells of the Advanced-EUTRA based on the result of the neighboring cell search. It is possible to prioritize the cells of the system, and it is possible to improve the efficiency of measurement.
Also, in this embodiment, information for identifying Advanced-EUTRA is arranged using the frequency resource of the secondary synchronization channel S-SCH, but the sequence used in the P-SCH is added to the Advanced- Compared with the method of arranging EUTRA identification information, there is an advantage that it is not necessary to perform correlation processing in the time domain that causes an increase in circuit scale.

(Second Embodiment)
The second embodiment of the present invention will be described below with reference to the drawings. In the second embodiment, a sequence different from the code Advanced SSC of the first embodiment is used as a sequence arranged in the imaginary part of the signal of the secondary synchronization channel S-SCH. Therefore, the base station apparatus 1a in the present embodiment is different from the base station apparatus 1 of FIG. 1 in that a synchronization signal generation unit 132a is provided instead of the synchronization signal generation unit 132, and other parts are the same. Further, the mobile station apparatus 2a in the present embodiment is different from the mobile station apparatus 2 in FIG. 3 in that the S-SCH demodulation / decoding section 283a is replaced with the S-SCH demodulation / decoding section 283 in the demodulation / decoding section 28 (FIG. 4). The other parts are the same. Therefore, in the description of the present embodiment, the description of each unit other than the synchronization signal generation unit 132a and the S-SCH demodulation / decoding unit 283a is omitted. The demodulation / decoding unit 28a of the mobile station apparatus 2a is different from the demodulation / decoding unit 28 of the mobile station apparatus 2 of FIG. 3 in place of the S-SCH demodulation / decoding unit 283. The only difference is that

FIG. 7 is a schematic block diagram illustrating a configuration of the synchronization signal generation unit 132a of the base station device 1a in the present embodiment. The synchronization signal generation unit 132a includes a PSC1 holding unit 1320, a PSC2 holding unit 1321, a PSC3 holding unit 1322, a selector 1323, a first code holding unit 1324, a first code selection unit 1325, an orthogonal modulation unit 1328, a multiplication unit 1332a, A binary code Ca holding unit 1333a is provided. In the figure, the same reference numerals (1320 to 1325, 1328 to 1331) are assigned to the portions corresponding to the respective portions in FIG.

The binary code Ca holding unit 1333a holds a predetermined binary code Ca having a length of 62. The multiplication unit 1332a multiplies the code SSC output from the first code selection unit 1325 by the binary code Ca held by the binary code Ca holding unit 1333a, and the multiplication result is sent to the multiplication unit 1330 of the orthogonal modulation unit 1328. Output. As a result, the code sequence of the signal arranged by the orthogonal modulation unit 1328 on the imaginary axis of the sequence 3 is the code that is the default code for the code SSC output from the first code selection unit 1325 that is the code sequence of the signal arranged on the real axis. The sequence 2 is multiplied by the binary code Ca.
Here, the multiplication of the code SSC and the binary code Ca by the multiplication unit 1332a represents the multiplication of each value of each series. For example, if the code SSC is "1, -1, 1, ... -1, -1" and the binary code Ca is "-1, -1, 1, ... 1, -1", These multiplication results are “1 × −1 = −1, −1 × −1 = 1, 1 × 1 = 1,... −1 × 1 = −1, −1 × −1 = 1”, that is, “−1, 1, 1,... −1, 1”.
In this way, the code PSC and the sequence 3 generated by the synchronization signal generation unit 132 are transmitted by the multiplexing / modulation processing unit 133, as in the first embodiment, the code PSC is the primary synchronization channel P-SCH of EUTRA, Sequence 3 is allocated to the EUTRA secondary synchronization channel S-SCH.

Since the signal of the secondary synchronization channel S-SCH is generated in this way, as information about the Advanced-EUTRA transmitted on the secondary synchronization channel S-SCH, the base station apparatus 1a uses the advanced-EUTRA communication. It becomes only the information indicating that is possible. That is, the mobile station apparatus 2a uses a sequence obtained by multiplying a sequence detected in the real part of the secondary synchronization channel S-SCH signal by a predetermined binary code Ca in the imaginary part of the secondary synchronization channel S-SCH signal. When detected, the base station apparatus transmitting the secondary synchronization channel S-SCH determines that communication using the Advanced-EUTRA is possible, and when not detected, the Advanced-EUTRA is used. It can be determined that the communication that has been performed cannot be performed.

FIG. 8 is a schematic block diagram showing a configuration of the S-SCH demodulation / decoding unit 283a of the mobile station device 2a in the present embodiment. The S-SCH demodulation / decoding unit 283a includes a complex signal separation unit 290, a first replica holding unit 291, a real part correlation unit 292, a first SSC identification unit 293, an imaginary part correlation unit 295a, and a binary code Ca holding unit 297a. , A multiplication unit 298a and a determination unit 299a. In the figure, the same reference numerals (290 to 293) are assigned to portions corresponding to the respective portions in FIG. 6, and the description thereof is omitted.

The binary code Ca holding unit 297a holds a predetermined binary code Ca having a length of 62, that is, the same binary code as the binary code Ca holding unit 1333a of the base station apparatus 1a. The multiplication unit 298a multiplies the imaginary part signal output from the complex signal separation unit 290 and the binary code Ca held by the binary code Ca holding unit 297a. The imaginary part correlation unit 295a calculates a correlation value between the real part signal output from the complex signal separation unit 290 and the multiplication result of the multiplication unit 298a. When the correlation value calculated by the imaginary part correlation unit 295 is less than a predetermined threshold, the determination unit 299a determines that the base station apparatus is an EUTRA cell that communicates using only EUTRA, and when the same as the predetermined threshold, or If the threshold is larger than the predetermined threshold, the base station apparatus determines that the cell is an Advanced-EUTRA cell that can communicate using Advanced-EUTRA, and outputs the determination result to the output selector 284.

Thus, in the present embodiment, whether or not the base station apparatus that has identified the SSC number and subframe number in the first SSC identification unit 293 and transmitted the reception signal in the determination unit 299a can communicate using Advanced-EUTRA. That is, it is identified whether or not the cell in the service area is an Advanced-EUTRA cell. Therefore, in this case, EUTRA information based on the SSC number and subframe number identified by the first SSC identification unit 293 is also used for information (physical cell ID, frame timing, etc.) regarding the cell of Advanced-EUTRA.

In this embodiment, as described above, the two radio communication schemes of EUTRA and Advanced-EUTRA have all parameters including the physical cell ID transmitted on the synchronization channel SCH as common values, and the base station apparatus 1a The parameter is transmitted as a signal placed on the real axis. Not limited to such an aspect, the two wireless communication systems have at least a part of the parameters as a common value, and a parameter having a common value is a signal placed on the real axis and a signal placed on the imaginary axis. You may enable it to transmit only in any one.

In the present embodiment, one type of binary code Ca is used. However, by preparing a plurality of types of binary code Ca and performing correlation processing in the mobile station device 2a, which binary code Ca is used by the base station device 1a. In the imaginary part of the signal of the secondary synchronization channel S-SCH, not only information on whether the cell is an Advanced-EUTRA cell but also other information (for example, the cell type is a Home eNB cell ( (Cells using base stations that can be easily installed and operated at the individual level or small business level) and MBMS (Multimedia Broadcast / Multicast Service) dedicated cells) It is also possible to do.

In the present embodiment, the first replica holding unit 291 holds all sequences for correlation processing. However, as in the first embodiment, a sequence is calculated and used every time correlation processing is performed. Of course it is also possible.
In this way, a sequence indicating that the cell is an Advanced-EUTRA cell, that is, the base station apparatus can communicate with the Advanced-EUTRA, is arranged in the imaginary part of the signal of the secondary synchronization channel S-SCH. By doing so, it is possible to arrange a synchronization channel capable of identifying Advanced-EUTRA without preparing a dedicated frequency resource and without affecting the operation of an existing EUTRA mobile station apparatus.

Since no dedicated frequency resource is required, it is possible to identify Advanced-EUTRA using a synchronization channel without degrading frequency utilization efficiency. Therefore, in the measurement in the communication state of the mobile station apparatus 2a of Advanced-EUTRA Therefore, it is possible to preferentially measure and report the Advanced-EUTRA cell, and to improve the efficiency of measurement. Further, the imaginary part of the signal of the secondary synchronization channel S-SCH is a signal obtained by multiplying the real part signal by a predetermined binary code Ca, so that the correlation for Advanced-EUTRA identification is made as compared with the first embodiment. The configuration of the S-SCH demodulator / decoder 283a that performs processing is suppressed from being complicated, and can be easily implemented.

(Third embodiment)
The third embodiment of the present invention will be described below with reference to the drawings. In the third embodiment, a sequence different from those in the first and second embodiments is used as a sequence arranged in the imaginary part of the signal of the secondary synchronization channel S-SCH. Therefore, the base station apparatus 1b in the present embodiment is different from the base station apparatus 1 of FIG. 1 in that a synchronization signal generation unit 132b is provided instead of the synchronization signal generation unit 132, and other parts are the same. Further, the mobile station apparatus 2b in this embodiment is different from the mobile station apparatus 2 of FIG. 3 in that the S-SCH demodulation / decoding section 283b is replaced with the S-SCH demodulation / decoding section 283 in the demodulation / decoding section 28 (FIG. 4). The other parts are the same. Therefore, in the description of the present embodiment, the description of each unit other than the synchronization signal generation unit 132b and the S-SCH demodulation / decoding unit 283b is omitted. Note that the demodulator / decoder 28b of the mobile station apparatus 2b is different from the demodulator / decoder 28 of the mobile station apparatus 2 of FIG. 3 in place of the S-SCH demodulator / decoder 283. The only difference is that

FIG. 9 is a schematic block diagram illustrating a configuration of the synchronization signal generation unit 132b of the base station device 1b in the present embodiment. The signal of the secondary synchronization channel S-SCH generated by the synchronization signal generation unit 132b includes the information of Advanced-UTRA among the code sequence candidates of the signal arranged on the imaginary axis. The code sequence corresponding to the parameter of the other wireless communication system is multiplied by a binary code Cb which is a predetermined code. The synchronization signal generation unit 132b includes a PSC1 holding unit 1320, a PSC2 holding unit 1321, a PSC3 holding unit 1322, a selector 1323, a first code holding unit 1324, a first code selection unit 1325, an orthogonal modulation unit 1328, and a second code. A selection unit 1327b, a multiplication unit 1332b, and a binary code Cb holding unit 1333b are provided. In the figure, the same reference numerals (1320 to 1325, 1328 to 1331) are assigned to the portions corresponding to the respective portions in FIG.

The second code selection unit 1327b reads the code SSC corresponding to the PSC number and the advanced SSC number designated by the control unit 10 from the first code holding unit 1324 and outputs the code SSC to the multiplication unit 1332b. The binary code Cb holding unit 1333b holds a predetermined binary code Cb having a length of 62. The multiplication unit 1332b multiplies the code SSC output from the second code selection unit 1327b and the binary code Cb held by the binary code Cb holding unit 1333b, and the multiplication result is sent to the multiplication unit 1330 of the orthogonal modulation unit 1328. Output.
Here, the multiplication of the code SSC and the binary code Cb by the multiplication unit 1332b represents the multiplication of each value of each series. For example, if the code SSC is "1, -1, 1, ... -1, -1" and the binary code Cb is "-1, -1, 1, ... 1, -1", These multiplication results are “1 × −1 = −1, −1 × −1 = 1, 1 × 1 = 1,... −1 × 1 = −1, −1 × −1 = 1”, that is, “−1, 1, 1,... −1, 1”.

Also, since the number of Advanced-SSC numbers (Advanced-EUTRA information) is scrambled for each PSC number, the number of code SSCs held in the first code holding unit 1324 (168 in the above example) The second code selection unit 1327b reads out and outputs the sequence corresponding to the Advanced SSC number and the PSC number from the first code holding unit 1324.
In this way, the code PSC and the sequence 3 generated by the synchronization signal generation unit 132b are converted into the EUTRA primary synchronization channel P− by the multiplexing / modulation processing unit 133 as in the first and second embodiments. The SCH, sequence 3, is arranged in the EUTRA secondary synchronization channel S-SCH.

FIG. 10 is a schematic block diagram showing the configuration of the S-SCH demodulation / decoding unit 283b of the mobile station device 2b in the present embodiment. The S-SCH demodulation / decoding unit 283b includes a complex signal separation unit 290b, a first replica holding unit 291, a correlation unit 292b, a first SSC identification unit 293, and a second SSC identification unit 296b. In the figure, the same reference numerals (291, 293) are assigned to portions corresponding to the respective portions in FIG. 6, and the description thereof is omitted.

The complex signal separation unit 290b separates the complex signal (secondary synchronization channel S-SCH signal after propagation path compensation) input from the input selector 280 into a real part signal and an imaginary part signal. Part signals are output sequentially. When outputting the real part signal and the imaginary part signal, the complex signal separation unit 290b also outputs a selection signal indicating whether the output signal is a real part signal or an imaginary part signal. The correlation unit 292b includes a real part signal, an imaginary part signal, a selection signal output from the complex signal separation unit 290b, a replica of the code SSC held by the first replica holding unit 291 and the synchronization unit 23. Based on the input PSC number, correlation processing described later is performed.
The correlation unit 292b and the second SSC identification unit 296b identify the sequence that has the maximum correlation from the correlation values that the correlation unit 292b performs the correlation process on the imaginary part signal, and the correlation value is less than a predetermined threshold value. Are determined to be EUTRA cells. Also, the second SSC identification unit 296b determines that the correlation value is the same as the predetermined threshold value or is larger than the predetermined threshold value, and determines the Advanced-EUTRA cell, and sets the Advanced SSC number from the sequence having the maximum correlation value. Identify.

FIG. 11 is a schematic block diagram showing the configuration of the correlation unit 292b in the present embodiment. The correlation unit 292b includes a first selector 300b, a first S / P (Serial / Parallel) conversion unit 301b, a second selector 302b, a second S / P conversion unit 304b, a multiplication unit 305b, and a first addition. 306b, a second adder 307b, a third adder 308b, a subtractor 309b, and a third selector 310b.

The first selector 300b selects and outputs the real part signal and the imaginary part signal based on the selection signal. The first S / P converter 301b performs serial / parallel conversion on the output of the first selector 300b. The second selector 302b sequentially selects and outputs all code SSC candidates assumed by the PSC number based on the input PSC number. The second S / P converter 304b performs parallel conversion on the signal from the second selector 302b. Multiplier 305b multiplies the output of first S / P converter 301b and the output of second S / P converter 304b.

The first adder 306b adds signals (bits) where the value of the binary code Cb is 1 among the signals multiplied by the multiplier 305b. The second adder 307b adds signals at locations (bits) where the value of the binary code Cb is -1. The third adder 308b adds the output of the first adder 306b and the output of the second adder 307b. The subtractor 309b subtracts the output of the second adder 307b from the output of the first adder 306b. The third selector 310b selects and outputs the output of the third adder 308b and the output of the subtractor 309b based on the selection signal.

The reception signal of a total of 62 subcarriers on both sides of 31 subcarriers sandwiching one subcarrier at the center of the system band of the secondary synchronization channel S-SCH input to the S-SCH demodulation / decoding unit 283b is a complex signal separation unit At 290b, the real part and the imaginary part are separated. The S-SCH demodulating / decoding section 283b first selects 62 real part signals out of the separated 62 subcarrier real part signals and imaginary part signals, together with a selection signal (selection signal = real part), to the correlation part 292b. input. Subsequently, the S-SCH demodulation / decoding unit 283b inputs the 62 imaginary part signals together with the selection signal (selection signal = imaginary part) to the correlation unit 292b. In the correlation unit 292b, the first selector 300b outputs the real part signal to the first S / P conversion unit 301b based on the input selection signal, if the selection signal = “real part”, and selects it. If signal = “imaginary part”, the imaginary part signal is output to the first S / P converter 301b.

The first S / P converter 301b performs serial / parallel conversion on the real part signal or the imaginary part signal input from the first selector 300b, and consists of 62 real part signals or 62 imaginary part signals. Output parallel signals. In addition, the second selector 302b includes 168 × 2 types of corresponding 168 × 2 × 3 types of replicas of the SSC code of 168 × 2 × 3 by the first replica holding unit 291 based on the PSC number input from the synchronization unit 23. Candidate replicas are sequentially read and output to the complex conjugate calculator 303b. The complex conjugate calculation unit 303b calculates the complex conjugate of the replica of the code SSC input from the second selector 302b, and outputs it to the second S / P conversion unit 304b. The second S / P converter 304b performs serial / parallel conversion on the complex conjugate of the input replica, and outputs 62 parallel signals.

Next, the multiplier 305b multiplies the parallel signal output from the first S / P converter 301b and the parallel signal output from the second S / P converter 304b. The multiplication unit 305 uses the binary code Cb code for each value of the multiplied parallel signal, the value at the position where the binary code Cb is “1” is sent to the first adder 306b, and the binary code Cb is “−1”. The position value is distributed to the second adder 307b and output. The first adder 306b and the second adder 307b add the values input to each, calculate the sum of the values input to each, and output the result.

The third adder 308b adds the output of the first adder 306b and the output of the second adder 307b and outputs the result. This is the processing itself for obtaining the correlation value between the signal input to the first S / P converter 301b and the signal input to the second S / P converter 304b. The subtractor 309b subtracts the output of the second adder 307b from the output of the first adder 306b and outputs the result. This is a process for obtaining a correlation value between a signal input to the first S / P converter 301b and a signal obtained by multiplying the signal input to the second S / P converter 304b by a binary code Cb. . The third selector 310b outputs the input (correlation value of the real part) from the third adder 308b based on the input selection signal, if the selection signal = “real part”, and the selection signal = If it is “imaginary part”, the input (correlation value of the imaginary part) from the subtractor 309b is output.

The correlation value of the real part output from the third selector 310b is input to the first SSC identification unit 293, and the correlation value of the imaginary part is input to the second SSC identification unit 296b. Thereafter, the first SSC identification unit 293 identifies the SSC number and the subframe number, and information indicating whether or not the base station apparatus that has transmitted the received signal in the second SSC identification unit 296b is an Advanced-EUTRA cell and Advanced Identify the SSC number. If it is not an Advanced-EUTRA cell, the Advanced SSC number becomes invalid and is discarded.

According to the present embodiment, it is possible to identify whether or not the base station apparatus can perform Advanced-EUTRA communication without preparing a dedicated frequency resource and without affecting the operation of the existing EUTRA mobile station apparatus. A synchronization channel that can be used can be arranged. Since no dedicated frequency resource is required, it becomes possible to identify whether or not the base station apparatus can communicate with the Advanced-EUTRA using the synchronization channel without degrading the frequency utilization efficiency. With measurement in the communication state of the mobile station apparatus 2b of EUTRA, it is possible to preferentially measure and report an Advanced-EUTRA cell, thereby improving the efficiency of measurement.

Further, by using a sequence obtained by converting an EUTRA SSC code sequence with a specified binary code as an Advanced-SSC, a code used for an Advanced-EUTRA SSC and a code used for an EUTRA SSC, as in the first embodiment. As compared with the first embodiment, it is possible to mount the correlator with a smaller number of circuits while keeping the correlation with the low correlation.

1, A / D converter 121, demodulation processor 122, controller 10, data modulator 130, control signal modulator 131, synchronization signal generator 132, multiplexing / modulation processor 133, D / A converter 134, and A / D conversion unit 22, synchronization unit 23, GI removal unit 24, S / P conversion unit 25, FFT unit 26, propagation path estimation / compensation unit 27, demodulation / decoding unit 28, MAC unit 29 in FIG. Modulation unit 30, IFFT unit 31, P / S conversion unit 32, GI addition unit 33, synchronization signal generation unit 132a in FIG. 7, S-SCH demodulation / decoding unit 283a in FIG. 8, and synchronization signal generation in FIG. Unit 132b and a program for realizing the functions of S-SCH demodulation / decoding unit 283b in FIG. 10 are recorded on a computer-readable recording medium, and the recording medium The recorded program read into the computer system, may be subjected to a treatment of each part by executing the processing of each unit or may be implemented by dedicated hardware. Here, the “computer system” includes an OS and hardware such as peripheral devices.

Further, the “computer-readable recording medium” means a storage device such as a flexible disk, a magneto-optical disk, a portable medium such as a ROM and a CD-ROM, and a hard disk incorporated in a computer system. Furthermore, the “computer-readable recording medium” dynamically holds a program for a short time like a communication line when transmitting a program via a network such as the Internet or a communication line such as a telephone line. In this case, a volatile memory in a computer system serving as a server or a client in that case is also used to hold a program for a certain period of time. The program may be a program for realizing a part of the functions described above, and may be a program capable of realizing the functions described above in combination with a program already recorded in a computer system.

As described above, the embodiment of the present invention has been described in detail with reference to the drawings. However, the specific configuration is not limited to this embodiment, and includes design changes and the like without departing from the gist of the present invention.

The present invention is suitable for use in a base station apparatus and a mobile station apparatus of a mobile communication network using Advanced-EUTRA, but is not limited to this.

DESCRIPTION OF SYMBOLS 1, 1a, 1b ... Base station apparatus 10 ... Control part 11 ... Reception antenna part 12 ... Reception part 13 ... Transmission part 14 ... Transmission antenna part 120 ... Reception analog circuit part 121 ... A / D conversion part 122 ... Demodulation processing part 130 Data modulation unit 131 Control signal modulation unit 132, 132a, 132b Synchronization signal generation unit 133 Multiplexing / modulation processing unit 134 D / A conversion unit 135 Transmission analog circuit unit 1320 PSC1 holding unit 1321 PSC2 holding unit 1322 ... PSC3 holding unit 1323 ... selector 1324 ... first code holding unit 1325 ... first code selecting unit 1326 ... second code holding unit 1327, 1327b ... second code selecting unit 1328 ... orthogonal modulation unit 1329 ... multiplication Unit 1330 ... Multiplier 1331 ... Adder 1332a, 1332b ... Multiplier 1333a ... Binary code Ca holding unit 1333b ... Binary code Cb holding unit 2, 2a, 2b ... Mobile station apparatus 20 ... Reception antenna unit 21 ... Reception analog circuit unit 22 ... A / D conversion unit 23 ... Synchronization unit 24 ... GI removal unit 25 ... S / P conversion unit 26 ... FFT unit 27 ... propagation path estimation / compensation unit 28, 28a, 28b ... demodulation / decoding unit 29 ... MAC unit 30 ... modulation unit 31 ... IFFT unit 32 ... P / S conversion unit 33 ... GI addition unit 34 ... D / A conversion section 35 ... transmission analog circuit section 36 ... transmission antenna section 230 ... first correlator 231 ... second correlator 232 ... third correlator 233 ... first buffer 234 ... second buffer 235 ... third buffer 236 ... Sector timing detector 280 ... Input selector 281 ... Control signal demodulation / decoding unit 282 ... Data signal demodulation / decoding unit 283, 283a, 283b ... SS H demodulation / decoding unit 284 ... output selector 290, 290b ... complex signal separation unit 291 ... first replica holding unit 292 ... real part correlation unit 292b ... correlation unit 293 ... first SSC identification unit 294 ... second replica holding Unit 295, 295a ... imaginary part correlation unit 296, 296b ... second SSC identification unit 297a ... binary code Ca holding unit 298a ... multiplication unit 299a ... determination unit 300b ... first selector 301b ... first S / P conversion unit 302b ... second selector 303b ... complex conjugate calculation unit 304b ... second S / P conversion unit 305b ... multiplication unit 306b ... first adder 307b ... second adder 308b ... third adder 309b ... subtraction 310b ... Third selector

Claims (11)

1. A base station apparatus that communicates with two different wireless communication methods,
   Of the two wireless communication systems, a signal obtained by orthogonal modulation by arranging a synchronization channel signal representing a parameter of one wireless communication system on a real axis and a synchronization channel signal representing a parameter of the other wireless communication system on an imaginary axis Is transmitted in a synchronization channel.
2. The signal arranged in the synchronization channel includes a first synchronization signal for time synchronization and a second synchronization signal for specifying a parameter when communicating with the base station apparatus,
   The base station apparatus according to claim 1, wherein the signal of the synchronization channel that is orthogonally modulated is the second synchronization signal.
3. 2. The base station apparatus according to claim 1, wherein the code sequence of the signal arranged on the real axis and the code sequence of the signal arranged on the imaginary axis are low-correlation sequences.
4. The code sequence of the signal arranged on the real axis and the code sequence of the signal arranged on the imaginary axis are the same for a part of the series, and the remaining parts of the series are low-correlation series. The base station apparatus according to claim 1, wherein:
5. The base station apparatus according to claim 1, wherein the code sequence of the signal arranged on the imaginary axis is a sequence obtained by multiplying the code sequence of the signal arranged on the real axis by a predetermined code.
6. The code sequence of the signal arranged on the imaginary axis is a sequence obtained by multiplying a code sequence corresponding to the parameter of the other radio communication scheme by a predetermined code among the code sequence candidates of the signal arranged on the real axis. The base station apparatus according to claim 1, wherein the base station apparatus is provided.
7. 2. The base according to claim 1, wherein the two wireless communication systems use at least a part of the parameters as a common value, and transmit a parameter having a common value as a signal arranged on the real axis. Station equipment.
8. The base station apparatus according to claim 7, wherein the parameter having a common value is information for identifying a base station apparatus.
9. A receiving unit for receiving a synchronization channel transmitted from the base station device;
   A complex signal separation unit that separates the received synchronization channel signal into a real part signal that is a real axis signal and an imaginary part signal that is an imaginary axis signal;
   A mobile station apparatus comprising: a parameter acquisition unit that acquires a parameter of a wireless communication scheme used by the mobile station apparatus for communication among parameters represented by each of the real part signal and the imaginary part signal; .
10. A wireless communication system comprising: a base station device that communicates with two different wireless communication methods; and a mobile station device that communicates with the base station device using at least one of the two wireless communication methods. And
    The base station apparatus arranges a synchronization channel signal representing a parameter of one of the two wireless communication systems on a real axis and a synchronization channel signal representing a parameter of the other wireless communication system on an imaginary axis. The quadrature-modulated signal is placed in the synchronization channel and transmitted,
    The mobile station device
    A receiver for receiving the synchronization channel;
    A complex signal separation unit that separates the received synchronization channel signal into a real part signal that is a real axis signal and an imaginary part signal that is an imaginary axis signal;
    A wireless communication system comprising: a parameter acquisition unit that acquires a parameter of a wireless communication method used by the mobile station device for communication among parameters represented by each of the real part signal and the imaginary part signal .
11. Parameters in a wireless communication system comprising: a base station device that communicates with two different wireless communication methods; and a mobile station device that communicates with the base station device using at least one of the two wireless communication methods An acquisition method,
    The base station apparatus places a synchronization channel signal representing a parameter of one of the two wireless communication systems on a real axis and a synchronization channel signal representing a parameter of the other wireless communication system on an imaginary axis. A first process of transmitting a quadrature modulated signal arranged in a synchronization channel;
    A second process in which the mobile station apparatus receives the synchronization channel;
    A third process in which the mobile station apparatus separates the synchronization channel signal received in the first process into a real part signal that is a real axis signal and an imaginary part signal that is an imaginary axis signal;
    The mobile station apparatus includes a fourth step of acquiring a parameter of a wireless communication method used by the mobile station apparatus for communication among parameters represented by each of the real part signal and the imaginary part signal. Characteristic parameter acquisition method.

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