JP2002368648A - Code estimating device and code estimating method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To solve the problems of conventional code estimating devices being unable to have estimated a code when a plurality (not necessarily limited to integer) of information symbols exist in one frame, has no means of enhancing the S/N and can have only estimated only prepared finite nonlinear code sequences. SOLUTION: A correlation fluctuation detection frame correlation detector 1 takes autocorrelation by a correlation width for a prescribed signal period, as to a reception signal and detects a length of the frame, by using the integral value of the absolute values of fluctuations of the correlation values. A 1st frame spread signal decoder 2 cancels the signal component of an information symbol from the 1st frame signal, with respect to the received signal to strike off only the signal component of a spread code. A 2nd frame spread signal decoder 3 cancels the signal component of an information symbol from the 2nd and succeeding frame signals, to make only the signal component of the spread code float. An inter-frame spread signal averaging processing unit 4 discriminates the code of the frames in the unit of chips and provides an output of the result as the spread code.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a code estimating apparatus and a code estimating method, and more particularly, to a code estimating apparatus and a code estimating method for estimating a spreading code of a direct spread wave whose spreading code is unknown or a generating polynomial thereof.

[0002]

2. Description of the Related Art As one of communication systems, a direct spread spectrum communication system is known. In this communication method, a PN (Pseudorandom Noi
se) A spread code called a sequence is multiplied by a signal to be transmitted, and the frequency spectrum of the transmission signal is transmitted as a spread spectrum signal (direct spread wave) spread widely by several hundreds to several thousand times. After converting the spread spectrum signal (direct spread wave) to a baseband signal,
The transmission signal of the original frequency band is obtained by multiplying the same spreading code as the spreading code used on the transmitting side and demodulated.

[0003] In this direct spread spectrum communication system,
Since the signal is transmitted over a wide band, even if there is an interference wave in the transmission band of the signal, its influence can be suppressed to a very small level, so that communication is not easily disturbed and many users can use the same frequency band at the same time. However, since they do not interfere with each other, multiple access is possible, and since the frequency spectrum of the signal is spread over a very wide band, the signal power per unit band is very small. Since it can only be seen and cannot be demodulated without using the same spreading code as the transmitting side, it has features such as excellent confidentiality and has been widely used in recent years.

In the direct spread spectrum communication system described above, it is naturally assumed that the legitimate receiving side knows the same spreading code as the transmitting side in advance, and the spreading code used on the transmitting side is not known. Otherwise, it cannot be demodulated. However, for special reasons such as signal interception, there is a case where it is necessary to demodulate even if the spreading code of the received direct spread wave is unknown. In such a case,
A code estimating apparatus is used which receives a direct spread wave whose spreading code is unknown, converts it into a baseband signal, estimates a generator polynomial of an original linear code sequence from the baseband signal, and outputs the generated polynomial.

[0005] This code estimating apparatus cannot cope with a case where a plurality of information symbols (not limited to an integer) are included in one frame. Therefore, conventionally, a code sequence previously prepared under the condition of one information in one frame is used. Are brute-force correlated, and a correlated generator polynomial is output. If the above generator polynomial can be estimated, a spreading code estimated to have been used on the transmission side can be generated using the generator polynomial, and demodulation of a direct spread wave can be performed by using this.

FIG. 9 is a block diagram showing an example of such a conventional code estimating apparatus. In the figure, a received unknown direct spread wave is converted into a baseband signal and input to a frame correlation detector 11. This frame correlation detector 1
Reference numeral 1 indicates an autocorrelation that is slightly shifted from the head of the input baseband signal. When autocorrelation is performed in a portion where a frame is repeated, a large peak is generated in the correlation integral value, so that the frame length can be detected. When this is repeated for several frames, the correlation integral value periodically increases for each frame. Therefore, by averaging the periods, the frame length can be accurately obtained.

[0007] A brute force code correlator 12 receives as input the detection signal of the frame length detected by the frame correlation detector 11 and a baseband signal, and generates a linear code string with the number of stages of a generator polynomial based on the frame length. That
A round robin is performed on a code sequence prepared in advance, and a linear code string having the highest correlation and a generator polynomial thereof are output. In this case, the brute-force code correlator 12 can cope with a nonlinear code sequence under a finite condition by correlating with a nonlinear code sequence prepared in advance in addition to the linear code.

[0008]

However, in the above-mentioned conventional code estimating apparatus, not only the condition that the received direct spread wave is one information symbol in one frame, but also
There is also a direct spread wave in which a plurality of (not necessarily an integer) information symbols are included in one frame. In this case, even if the frame correlation detector 11 performs autocorrelation, the correlation integral value in the frame does not increase. Since the correlation cannot be obtained, it is impossible to analyze the frame length. The brute force code correlator 12
Is inverted at the change point of the information symbol, and a highly accurate correlation cannot be performed, so that the analysis of the spread code becomes impossible.

In the above-mentioned conventional code estimating apparatus, when a baseband signal having a poor signal-to-noise ratio (S / N) is input, there is no means for improving the S / N. Estimation of the generator polynomial output from 12 does not provide a high correct answer rate.

Further, in the above-mentioned conventional code estimating apparatus, the brute-force code correlator 12 takes a correlation with a non-linear code sequence prepared in advance in addition to a linear code to cope with the non-linear code sequence. However, since the non-linear code string is finite, there is a problem that only a finite code prepared in advance can be applied to the non-linear code string.

Conventionally, a correlation value between a pseudo-noise code or a modulated signal (direct spread wave) modulated by the pseudo-noise code and a generated pseudo-noise code is obtained, and the pseudo-noise code or direct reception code received from the correlation value is obtained. There is known a detection apparatus that calculates an estimated phase of a pseudo-noise code included in a spread wave, and further estimates a true phase from a plurality of estimated phases obtained in a state where the phase difference is different (Japanese Patent Laid-Open No. 2001-2001). 36429). Here, one frame of the code includes one piece of information or two or more pieces of divided information, and each piece of information is divided in units of a chip. However, this conventional detection device detects synchronization in units of a chip. It does not detect synchronization of an information unit in which a plurality of chips are gathered, and cannot estimate a generator polynomial of a spread code of a received directly spread wave under extremely severe conditions that a spread code is unknown.

The present invention has been made in view of the above points,
Even when a plurality of (not necessarily integer) information symbols are included in one frame, a code capable of accurately detecting a change point of the information symbol, removing a signal component of the information symbol, and restoring a spread code. It is an object to provide an estimation device and a code estimation method.

Another object of the present invention is to improve the S / N by averaging the codes between frames even for a signal having a poor S / N, and to increase the correct answer rate for estimating the spreading code. To provide a code estimating apparatus and a code estimating method.

Still another object of the present invention is to provide a code estimating apparatus and a code estimating method capable of estimating an unknown code sequence irrespective of a linear / non-linear code.

[0015]

According to a first aspect of the present invention, there is provided a code estimating apparatus for receiving a direct spread wave whose spreading code is unknown, and converting the direct spread wave into a baseband signal. After the conversion, a code estimating apparatus for at least estimating a spreading code, wherein the autocorrelation is obtained with a correlation width of a predetermined signal section while sliding the correlation position little by little with respect to the baseband signal, and the absolute value of the variation of the correlation value is calculated. If the integrated value is smaller than a predetermined value, the frame is determined to be the same frame, and a correlation variation detection type frame correlation detector for detecting the frame length is provided.

According to another aspect of the present invention, there is provided a code estimating method for receiving a direct spread wave having an unknown spreading code and converting the direct spread wave into a baseband signal. A code estimating method for at least estimating a spreading code, wherein an autocorrelation is obtained with a correlation width of a predetermined signal section while sliding a correlation position little by little with respect to a baseband signal, and an integral value of an absolute value of a variation of the correlation value is obtained. If the value is smaller than the predetermined value, it is determined that the same frame has appeared and a frame length is detected.

In the code estimating apparatus and the code estimating method according to the first and the eleventh aspects of the present invention, an autocorrelation is obtained by a correlation width of a predetermined signal section while sliding a correlation position little by little with respect to a baseband signal. When the integral value of the absolute value of the value change is smaller than a predetermined value, it is determined that the same frame has appeared and the frame length is detected.

According to another aspect of the present invention, there is provided a code estimating apparatus for receiving a direct spread wave having an unknown spreading code and converting the direct spread wave into a baseband signal. A code estimating apparatus for at least estimating a spreading code, wherein a signal component of an information symbol is canceled from a signal of a first frame with respect to a baseband signal based on a known frame length, so that only a signal component of the spreading code is raised. A first frame spread signal reconstructor, a baseband signal, and a spread signal reconstructed from the first frame by the first frame conversion signal reconstructor are received as inputs, and information symbols are derived from signals of the second and subsequent frames of the baseband signal. And a second frame and subsequent spread signal decompressor for canceling the signal components of the first and second frames to raise only the signal components of the spread code, After chip integration of the spread signal of the first frame restored by the above and the spread signal of the second and subsequent frames restored by the spread signal restorer for the second and subsequent frames, an addition result obtained by adding in all the frames, An inter-frame spread signal averaging processor that performs code determination for each chip and outputs the result as a spread code.

According to a twelfth aspect of the present invention, there is provided a code estimating method for receiving a direct spread wave having an unknown spreading code and converting the direct spread wave into a baseband signal. A code estimation method for at least estimating a spreading code, wherein a signal component of an information symbol is canceled from a signal of a first frame with respect to a baseband signal based on a known frame length so that only a signal component of the spreading code is raised. A first step and a first step
Based on the spread signal restored from the frame, the second step of canceling the signal component of the information symbol from the signal of the second and subsequent frames of the baseband signal to raise only the signal component of the spread code and the first step After the chip integration of the spread signal of the first frame and the spread signals of the second and subsequent frames restored in the second step, the addition result obtained by adding in all the frames is sign-determined for each chip. And outputting the spread code as a spread code.

In the code estimating apparatus and the code estimating method according to the present invention, when the frame length of the received direct spread wave is known, the same corresponding position in the frame is determined by the correlation width of the entire frame length. , The autocorrelation between the frames is obtained over a plurality of frames, the change point of the information symbol is detected, the information symbol component is removed, and only the signal component of the spread code can be restored.

According to a third aspect of the present invention, there is provided a code estimating apparatus according to the third aspect of the present invention, further comprising: A first frame spread signal reconstructor for canceling a signal component of an information symbol from a signal of a first frame from a signal of a first frame to raise only a signal component of a spread code, a baseband signal, and a first frame conversion signal reconstructor And a spread signal restored from the first frame, and the spread signal after the second frame, in which the signal component of the information symbol is canceled from the signal of the second and subsequent frames of the baseband signal and only the signal component of the spread code emerges A decompressor, a spread signal of the first frame reconstructed by the first frame spread signal reconstructor, and a spread signal reconstructor of the second and subsequent frames. An inter-frame spread signal averaging unit that performs code integration for each frame after chip integration of the spread signal of the second and subsequent frames obtained and adds the results of addition in all frames, and outputs the result as a spread code. And a configuration having:

According to a thirteenth aspect of the present invention, there is provided a code estimating method for receiving a direct spread wave having an unknown spreading code and converting the direct spread wave into a baseband signal. A code estimating method for at least estimating a spreading code, wherein an autocorrelation is obtained with a correlation width of a predetermined signal section while sliding a correlation position little by little with respect to a baseband signal, and an integral value of an absolute value of a variation of the correlation value is obtained. If the value is smaller than the predetermined value, a first step of judging that the same frame has appeared and detecting the frame length is performed. A second step of canceling the signal component of the information symbol to raise only the signal component of the spread code, and recovering from the first frame by the second step. A third step of canceling the information symbol signal component from the signal of the second and subsequent frames of the baseband signal to raise only the signal component of the spread code based on the spread signal thus obtained, and a third step restored in the second step. After the chip integration of the spread signal of one frame and the spread signal of the second and subsequent frames restored in the third step, the addition result obtained by adding in all the frames is subjected to code determination for each chip and spread. And a fourth step of outputting as a code.

In the code estimating apparatus and method according to the third and thirteenth aspects of the present invention, an autocorrelation is obtained with a correlation width of a predetermined signal section while sliding a correlation position little by little with respect to a baseband signal, and a correlation value of a correlation value is calculated. If the integrated value of the absolute value of the fluctuation is smaller than a predetermined value, it is determined that the same frame has appeared, and the frame length is detected. By taking a correlation and detecting a change point of the information symbol, the information symbol component can be removed. Further, in the above invention, the inter-frame spread signal averaging processor or the fourth step can average the spread signal between frames to obtain a code string.

According to another aspect of the present invention, there is provided a code estimating apparatus according to the present invention, wherein one frame of a baseband signal is used as a correlation criterion based on a known frame length, and n frames after the first frame. All the frames up to the frame are correlated with one frame as a correlation criterion, a change point of the correlation value is added, and information in one frame of information symbol as a correlation criterion is added based on the addition result. Restoring the spread signal information of one frame as the correlation reference by estimating the symbol and canceling out the information symbol is repeated by sequentially switching the frame as the correlation reference for all frames from the first frame to the last frame. Thus, a first spread signal reconstructor for restoring spread signals of all frames for each frame and a first spread signal reconstructor After the chip integrating the spread signal of each frame, the addition result obtained by adding every frame,
And a first inter-frame spread signal averaging processor that performs code determination for each chip and outputs the result as a spread code.

According to a fourth aspect of the present invention, there is provided a code estimating method for receiving a direct spread wave having an unknown spreading code and converting the direct spread wave into a baseband signal. A code estimating method for estimating at least a spreading code, wherein one frame having a baseband signal is used as a correlation criterion based on a known frame length, and a correlation criterion is used for all frames from the first frame to n frames. By obtaining a correlation between one frame and one frame, adding a change point of the correlation value, estimating an information symbol in an information symbol of one frame as a correlation reference based on the addition result, and canceling the information symbol. Restoring the spread signal information of one frame as a correlation criterion is performed by setting the frame as a correlation criterion to all frames from the first frame to the last frame. And sequentially switching and repeating, the first step of restoring the spread signal of all frames for each frame and the spread signal of each frame restored in the first step are integrated in a chip, and then added in all frames. And a second step of determining a code of the obtained addition result for each chip and outputting it as a spread code.

According to the code estimating apparatus and the estimating method of the present invention described in claims 4 and 14, the frame length of the received direct spread wave is known, and the same width within the frame is determined by the correlation width of the entire frame length. Autocorrelation between frames is obtained for a plurality of frames at the corresponding position, a change point of an information symbol is detected, an information symbol component is removed, and only a signal component of a spread code can be restored.

According to a fifth aspect of the present invention, there is provided a code estimating apparatus according to the fifth aspect of the present invention, in which an autocorrelation is obtained with a correlation width of a predetermined signal section while sliding a correlation position little by little with respect to a baseband signal. If the integrated value of the absolute value of the variation of the correlation value is smaller than a predetermined value, a correlation variation detection type frame correlation detector that determines that the same frame has appeared and detects the frame length; One frame of the band signal is used as a correlation criterion. Correlation between one frame as a correlation criterion and all frames from the first frame to the nth frame is obtained, and a change point of the correlation value is added. By estimating an information symbol in one frame of information symbol as a correlation criterion based on the addition result and canceling the information symbol, a correlation criterion is obtained. Restoring the spread signal information of one frame is repeated by sequentially switching the frame used as the correlation criterion for all frames from the first frame to the last frame, so that the spread signal of all frames is restored for each frame. After the chip integration of the spread signal of each frame restored by the first spread signal restorer and the addition result obtained by adding in all the frames,
And a first inter-frame spread signal averaging processor that performs code determination for each chip and outputs the result as a spread code.

In order to achieve the above object, a code estimating method according to a fifteenth aspect of the present invention provides a code estimating method comprising: receiving a direct spread wave whose spread code is unknown, converting the direct spread wave into a baseband signal; A code estimating method for at least estimating a spreading code, wherein an autocorrelation is obtained with a correlation width of a predetermined signal section while sliding a correlation position little by little with respect to a baseband signal, and an integral value of an absolute value of a variation of the correlation value is obtained. If it is smaller than the predetermined value, a first step of detecting that the same frame has appeared and detecting the frame length, and, based on the detection result of the frame length, one frame having a baseband signal as a correlation criterion, For all frames up to the frame, a correlation between one frame as a correlation reference and a change point of the correlation value are added,
The correlation criterion is to estimate the information symbol in the information symbol of one frame as the correlation criterion based on the addition result and to restore the spread signal information of one frame as the correlation criterion by canceling the information symbol. A second step of sequentially switching and repeating the frames for all frames from the first frame to the last frame to restore spread signals of all frames for each frame, and a spread signal of each frame restored in the second step And a third step of, after chip integration, adding the results obtained by adding in all frames, determining the sign of each chip and outputting the result as a spread code.

In the code estimating apparatus and the estimating method according to the fifth and fifteenth aspects of the present invention, similar to the above invention, the baseband signal is self-slid by a correlation width of a predetermined signal section while sliding the correlation position little by little. When the correlation is obtained and the integrated value of the absolute value of the fluctuation of the correlation value is smaller than a predetermined value, it is determined that the same frame has appeared, and the frame length can be detected.

In order to achieve the above object, a code estimating apparatus according to a sixth aspect of the present invention receives a signal output from a first inter-frame spread signal averaging processor as a temporary decision spread code, A second spread signal reconstructor for canceling the signal component of the information symbol for each frame and restoring only the signal component of the spread code for each frame and restoring the spread signal of the entire frame, and a second spread signal reconstructor And a second inter-frame spread signal averaging processor for averaging the restored spread signals of the respective frames output from the second unit and outputting a spread code.

In order to achieve the above object, a code estimating method according to a sixteenth aspect of the present invention receives the signal obtained in the third step as a temporary decision spreading code, A fourth step of canceling the signal component of the information symbol to raise only the signal component of the spread code to re-decompress the spread signal of all frames; and averaging the restored spread signal of each frame restored by the fourth step. And outputting a spread code.

According to the apparatus and method of the present invention, the spread signals of all frames are restored again,
Since a spread code is output by averaging the restored spread signal of each frame, even if an error due to noise or the like is included in the tentative decision spread code, the error can be reduced by the above-described re-restoration and averaging process. The effect can be eliminated.

Here, the first frame spread signal reconstructor uses the first frame of the baseband signal as a reference for the correlation width of the signal section of the entire frame length, and performs the inter-frame inter-frame over the same corresponding position in the frame. A first frame information symbol change point detector that detects a position where the sign of the correlation value is inverted, and determines a position that appears commonly in each frame as an information symbol change point of the first frame; A first frame inter-change-point sign inverter for inverting all the signs of signals between any of the odd-numbered to even-numbered or even-odd-numbered information symbol change points from the start of the first frame; be able to.

The second and subsequent spread signal decompressors receive as input the baseband signal and the spread signal sequence reconstructed from the first frame after the information symbol components have been removed and the code has been determined. Using the spread signal sequence restored from the first frame as a correlation criterion, and a correlation value integrated value obtained by correlating the frames over a plurality of frames at the same corresponding position in the frame with the correlation width of the signal section of the entire frame length. And a second and subsequent information symbol change point detector for outputting peak and dip position information, and a correlation value integrated value from the second and subsequent information symbol change point detectors from the peak of the integrated value of the second and subsequent frames in the dip interval It can be configured to include a sign inverter between the change points after the second frame in which all the signs of the baseband signal are inverted.

Further, the first spread signal reconstructor uses one frame of the baseband signal as a correlation criterion based on the detection result of the frame length, and performs correlation for all frames from the first frame to n frames. A correlation between one frame as a reference frame is obtained, a change point at which the sign of the correlation value is inverted is detected, and a position commonly appearing in each frame is determined as an information symbol change point of one frame based on the correlation reference. Information symbol change point detector and 1
From the start of the frame, an inter-change point sign inverter for inverting all the signs of signals between any of the odd-numbered to even-numbered or even-to-odd information symbol change points, and The operation by the change point detector and the inter-change point sign inverter is sequentially switched and repeated for all frames from the first frame to the last frame as a correlation reference, thereby restoring spread signals of all frames for each frame. It is good also as a structure which performs.

Further, the second spread signal reconstructor receives the signal output from the first inter-frame spread signal averaging processor as a temporary decision spreading code, uses the temporary decision spreading code as a correlation reference, An information symbol change point detector that outputs position information of peak and dip of a correlation value integrated value obtained by taking a correlation between frames over a plurality of frames at the same corresponding position in the frame with a correlation width of a signal section of a frame length; Alternatively, a configuration may be adopted in which a sign inter-change point inverter inverts all the signs of the signals of the respective frames in the section from the peak of the correlation value integration value from the information symbol change point detector to the dip.

[0037]

Next, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a block diagram showing an embodiment of a code estimating apparatus according to the present invention. The present embodiment comprises a correlation variation detection type frame correlation detector 1, a first frame spread signal restorer 2, a second frame or later spread signal restorer 3, and an inter-frame spread signal averaging processor 4. Have been.

The correlation fluctuation detection type frame correlation detector 1 comprises:
When the correlation value of the received signal (spread modulation signal) of the baseband band is gradually slid, the autocorrelation is obtained with the correlation width of the predetermined signal section, and the integrated value of the absolute value of the fluctuation of the correlation value is smaller than the predetermined value. It is determined that the same frame has appeared, and the frame length is detected from the time difference of the autocorrelation that minimizes the integrated value of the absolute value of the correlation value change under the conditions. If this is repeated for several frames, a correlation can be obtained periodically for each frame. Therefore, the frame length can be accurately obtained by averaging the periods. When a plurality of information symbols (not an integer) are included in a frame, the correlation cannot be completely obtained even if the autocorrelation is obtained at a position where a complete frame correlation can be obtained. The part with the negative correlation and the part with the negative correlation are canceled out, and the correlation integral value does not increase.
Correlation judgment cannot be performed accurately.

Therefore, in the present invention, the integrated value of the absolute value of the variation of the correlation value is used for determining the correlation. If the correlation cannot be obtained, the sign of the correlation value changes frequently, and the absolute value of the fluctuation of the correlation value also increases.
A significant change in the correlation value occurs only at the change point of the information symbol, and the correlation value only slightly changes due to noise in other sections. Therefore, the integral of the absolute value of the variation of the correlation value is
If the correlation value fluctuation due to the information symbol and the fluctuation due to noise are smaller than a predetermined value determined with a margin,
It can be determined that the correlation has been obtained.

The first frame spread signal reconstructor 2 applies a first frame spread signal to the baseband received signal based on the frame length detection result by the correlation variation detection type frame correlation detector 1.
A circuit unit for canceling the signal component of the information symbol from the signal of the frame to raise only the signal component of the spread code. The circuit unit is composed of the first frame information symbol change point detector 21 and the first frame inter-change point code inverter 22. It is configured. The first frame information symbol change point detector 21 calculates the autocorrelation between the frames over a plurality of frames at the same corresponding position in the frame using the first frame as a correlation criterion based on the correlation width of the signal section of the entire frame length. The position where the sign of the value is inverted is detected, and the position that appears in each frame in common is determined as the information symbol change point of the first frame. Then, the first frame inter-change-point sign inverter 22 is:
All the signs of signals between any of the odd-numbered to even-numbered or even-odd-numbered information symbol change points from the start of the first frame are inverted to restore the spread signal of the first frame.

The second frame and subsequent spread signal decompressor 3 is a circuit unit for canceling the information symbol signal components from the second and subsequent frame signals to raise only the spread code signal components. It comprises a change point detector 31 and a sign inverter 32 between the change points after the second frame. The information symbol change point detector 31 for the second and subsequent frames takes the correlation between frames over a plurality of frames at the same corresponding position in the frame using the provisionally determined spreading code as a correlation criterion based on the correlation width of the signal section of the entire frame length, The dip position is output from the peak of the correlation integral value. From the second frame onward, the inter-change point sign inverter 32 outputs the second
All the signs of the second frame and subsequent frames in the section from the peak to the dip of the correlation integral value detected by the information symbol change point detector 31 after the frame are inverted, and the spread signal after the second frame is restored.

The inter-frame spread signal averaging processor 4 integrates the spread signal restored in each frame after chip integration, adds in all frames, and outputs a code determined for each chip as a spread code. Note that a frame is formed by assembling chips by the number of spreading codes. When the spreading code is a linear code, the number of chips in one frame is usually a power of 2 minus 1, and each frame is repeatedly multiplied by the same spreading code. When multiplying, the sign is multiplied by 1 when the sign is 0 and by -1 when the sign is 1. The relationship between frames and information symbols is generally asynchronous with each other.

Next, the operation of this embodiment will be described with reference to FIGS. After a directly-spread wave whose spreading code is unknown is received by a receiving unit (not shown), it is converted into a baseband reception signal (spread modulation signal) and supplied to the correlation fluctuation detection type frame correlation detector 1, where it is slightly transmitted. The autocorrelation is performed with the correlation width of the predetermined signal section while sliding the correlation position at a time, and when the integrated value of the absolute value of the fluctuation of the correlation value is smaller than the predetermined value, it is determined that the same frame has appeared, and furthermore, the condition Then, the frame length is detected from the time difference of the autocorrelation that minimizes the integral value of the absolute value of the variation of the correlation value. If this is repeated for several frames, a correlation can be obtained periodically for each frame. Therefore, by averaging the periods, the frame length can be accurately detected.

This correlation variation detection type frame correlation detector 1
Is supplied to the first frame information symbol change point detector 21 together with the baseband spread modulation signal. The first frame information symbol change point detector 21 multiplies the information symbol shown in FIG. 2A by the spread code string (here unknown) shown in FIG. (The spread modulation signal) is received as an input. Here, as a received signal condition, an example of a received signal in which a spreading code of one frame does not correspond one-to-one with respect to one information symbol, and is asynchronous and is applied to a plurality of (not an integer) information symbols. ing.

First frame information symbol change point detector 2
1 detects the sign change point timing of the correlation value when the correlation between the second and subsequent frames is obtained using the first frame of the received signal shown in FIG. FIG. 2D shows the first frame of the received signal shown in FIG. 2C. The first frame information symbol change point detector 21 detects the first frame and the second and third frames of the received signal. The correlation value when correlating with
FIG. 11E shows a change point of the correlation value (a change point point with respect to the second frame is shown in FIG. 6F, and a change point point with the third frame is shown in FIG. 6G). ) Is detected.

Then, the first frame information symbol change point detector 21 uses the first frame of the received signal as a correlation criterion in the same manner as described above, calculates the correlation between the second and subsequent frames, and calculates the correlation value. Are added (accumulated) as shown in FIG. 2 (H). in this case,
Since information symbol change points in the second and subsequent frames occur randomly in each frame, they do not accumulate. However, only the information symbol change points in the first frame use the first frame as a correlation criterion. Appearing in the result in common, the sum of the second to n-th frames is accumulated by n-1 points as shown in FIG.

The first frame inter-change point sign inverter 22 is
As described above, only the information symbol change points of the first frame are accumulated by the first frame information symbol change point detector 21 as shown in FIGS. 2 (I) and 3 (A). When the symbol change point is extracted,
Based on this, information symbols in the first frame are estimated as shown in FIG. In this case, the information symbol can be definitely restored unless the information symbol change point is mistaken.

Therefore, as shown in FIG. 3C, only the spread signal information remains by inverting the sign of the received signal so as to cancel the information symbol. FIG. 3D shows the spread signal thus restored from the first frame by the first frame inter-change point sign inverter 22. However, the restored spread signal contains an error due to noise or the like. Therefore, as described later, the second
The error is reduced by averaging with the spread signal restored after the frame.

Next, the information symbol change point detector 31 for the second and subsequent frames is used by the first frame inter-change point sign inverter 22.
, And a spread signal restored from the first frame (that is, a tentatively determined spread code sequence) as input, the information symbol component shown in FIG. 4D is removed, and Using the provisionally determined spreading code sequence restored from the first frame after code determination as a correlation criterion, the correlation between the frames is calculated over a plurality of frames at the same corresponding position in the frame using the correlation width of the signal section of the entire frame length. ,
As shown in FIG. 4E, an integrated value of the correlation value is obtained. As shown in FIG. 4E, the integrated value of the correlation value has a peak or dip at the change point of the information symbol. Therefore, the information symbol change point detector 31 for the second and subsequent frames uses the position information of the peak and the dip. Is output. FIG. 4A shows an information symbol, FIG. 4B shows a spread code string, and FIG. 4C shows a received signal (spread modulation signal) obtained by multiplying the information symbol and the spread code string. These are the same as the signals shown in FIGS. 2A, 2B and 2C, respectively.

Sign changer 32 between change points after the second frame
Receives as input the position information of the peak and dip of the integrated value of the correlation value detected by the information symbol change point detector 31 after the second frame and the received signal (spread modulation signal) as shown in FIG. In the section from the peak to the dip, the sign of all the codes of the received signal after the second frame is inverted, and in the section from the dip to the peak, the sign is not inverted after the second frame of the received signal. Thus, the spread signals of the second and subsequent frames are restored as shown in FIG.

The difference between the restoration processing of the spread signal restorer 3 for the second and subsequent frames and the spread signal restorer 2 for the first frame is as follows.
Information symbol components are removed for the correlation criterion, and
The point is that the code is a temporarily determined spread code after code determination. This makes it easier to detect only the information symbol change point of each frame. In addition, since the spread signal restoration unit 3 detects the peak and dip of the integrated value of the correlation value in the second frame and thereafter, the information signal change point is erroneously detected as a change due to local noise in the middle. Is less likely to be done.

The spread signal signal restored from the first frame and the restored spread signal after the second frame are supplied to an inter-frame spread signal averaging processor 4, where the averaging process is performed. Is performed. The processing operation of the inter-frame spread signal averaging processor 4 will be described with reference to FIG.
The restored spread signal shown in (A) is received as an input signal, and since the restored spread signal still contains an error, the restored spread signals of all frames are added in frame units as shown in FIG. Then, the S / N is improved by obtaining the addition result shown in FIG. 2C, and then the addition result is subjected to code determination on a chip-by-chip basis to calculate a spread code string, thereby obtaining the result shown in FIG. The spreading code averaged as above is output.

As described above, according to this embodiment, 1
Multiple information symbols in the frame (not necessarily integers)
Even if it is included, the frame length can be analyzed, and the information symbol component can be erased to restore only the signal component of the spread code. Also, for signals with poor S / N, spread signals between frames are averaged and S / N
Is increased, and as a final result, a high correct answer rate of the spreading code estimation can be obtained. Further, the code sequence can be estimated regardless of whether the original code sequence is linear or non-linear.

Next, an embodiment of the code estimation method according to the present invention will be described. FIG. 6 shows a flowchart of an embodiment of the code estimation method according to the present invention. As shown in the figure, this embodiment is a code estimation method for receiving a direct spreading wave whose spreading code is unknown, converting the direct spreading wave into a baseband signal, and then at least estimating the spreading code. First, auto-correlation is performed with the correlation width of a predetermined signal section while sliding the correlation position little by little with respect to the baseband signal, and when the integrated value of the absolute value of the variation of the correlation value is smaller than the predetermined value, the same frame is obtained. Is detected and the frame length is detected (step 10).
1).

Subsequently, based on the frame length detection result in step 101, the above baseband signal is
The signal component of the information symbol is canceled from the signal of the first frame, and only the signal component (spread signal) of the spread code is raised (step 102). Subsequently, based on the spread signal restored from the first frame, the signal component of the information symbol is canceled from the signal of the second frame and subsequent frames of the baseband signal, and only the signal component of the spread code is lifted, thereby forming the second and subsequent frames. Is restored (step 103).

Then, the first data restored in step 102
After chip integration of the spread signal of the frame and the spread signal of the second and subsequent frames restored in step 103, the addition result obtained by adding in all frames is code-determined for each chip and the spread signal is averaged. And outputs it as a final spread code (step 104). According to the code estimating method of this embodiment, the same effects as those of the code estimating apparatus shown in FIG. 1 can be obtained.

Next, another embodiment of the present invention will be described. FIG. 7 is a block diagram showing another embodiment of the code estimating apparatus according to the present invention. In the figure, the same components as those of FIG. 1 are denoted by the same reference numerals, and description thereof will be omitted. In FIG. 7, the first frame spread signal restorer 5 repeats the process from the head data of each frame to restore the spread signal of each frame.

That is, the first frame spread signal restorer 5
Is composed of a frame information symbol change point detector 51 and a frame-to-frame change point sign inverter 52. 22, the spread signal of the first frame is restored, but unlike the previous embodiment, the first frame spread signal restorer 5 subsequently performs the spread signal restoration of each frame after the second frame. I do. That is, first, the frame information symbol change point detector 51 uses the first frame of the received signal as a correlation criterion, calculates the correlation between the second frame and the subsequent frames with the first frame, and calculates the change point of the correlation value. Are added (accumulated). In this case, the information symbol change points in the second and subsequent frames do not accumulate because they occur randomly in each frame, but only the information symbol change points in the first frame are based on the first frame as a correlation reference.
It appears in the correlation result of each frame in common, and is accumulated by n-1 points in the sum of the second to n-th frames.

Since the frame information symbol change point detector 51 accumulates only the information symbol change points of the first frame as described above, the inter-frame change point sign inverter 52 determines the information symbol change points of the first frame. When the information symbols are extracted, the information symbols in the first frame are estimated based thereon, and the sign of the received signal is inverted so as to cancel the information symbols, so that only the spread code information remains. In this manner, the spread signal restored from the first frame by the first frame inter-change point sign inverter 52 is obtained.

Subsequently, the frame information symbol change point detector 51 uses the second frame of the received signal as a correlation criterion, and calculates the correlation between the second frame and all the frames from the first frame to n frames. Then, the change points of the correlation values are added (accumulated). In this case, since the frame information symbol change point detector 51 accumulates only the information symbol change points of the second frame, the inter-frame change point sign inverter 52 extracts the information symbol change points of the second frame. , Based on which, the second
By estimating the information symbols in the frame and inverting the sign of the received signal so as to cancel the information symbols, only the spread code information remains. In this way, the spread signal restored from the first frame by the second frame inter-change point sign inverter 52 is obtained. Hereinafter, for the third and subsequent frames, the correlation criterion is sequentially changed in the same manner as described above, and spread signals for all frames are obtained in the same manner as described above.

After that, the inter-frame spread signal averaging processor 6 adds the restored spread signals of all the frames input from the inter-frame transition point code inverter 52 in frame units, and codes the addition result in chip units. By making a determination and calculating a spread code sequence, an averaged spread code is output. This operation itself is the same as the operation of the inter-frame spread signal averaging processor 4 described above. As a result, the averaged spread code is output from the inter-frame spread signal averaging processor 6, so that the processing may be terminated.

However, in this embodiment, in order to further improve the performance, the inter-frame spread signal averaging processor 6
Is input to the second frame spread signal restorer 7 as a temporary decision spread code, and the spread signal of each frame is restored.

The second frame spread signal reconstructor 7 is composed of a frame information symbol change point detector 71 and an inter-frame change point sign inverter 72, and is similar to the spread signal reconstructor 3 for the second and subsequent frames. Although the configuration is different from that of the spread signal decompressor 3 from the second frame onward, the spread signal of the entire frame is converted from the first frame to the last frame, not from the second frame, by the first frame spread signal decompressor 5. And restore again. Then, in the inter-frame spread signal averaging processor 4, all frames of the restored spread signal input from the second frame spread signal restorer 7 are added in frame units, and the result of the addition is sign-determined in chip units. , And outputs an averaged spread code by calculating a spread signal sequence.

This embodiment has the same features as the embodiment of FIG. 1, but has a higher S / N ratio than the embodiment of FIG.
The effect of improvement is obtained. In the embodiment of FIG. 1, since the temporary decision spreading code restored by the first frame spread signal restorer 2 still includes an error, the second frame and subsequent frames use the spread signal restorer 3 based on the error. When the spread signal restoring process for the second and subsequent frames is performed, the error of the tentative decision spreading code restored by the first frame spread signal restorer 2 spreads to the second and subsequent frames. Errors are not completely eliminated.

On the other hand, in this embodiment shown in FIG. 7, the spread code obtained by averaging the spread signal of each frame by the inter-frame spread signal averaging processor 6 is used as the temporary judgment spread code in the second frame. Since the spread signal of the entire frame is re-restored by the spread signal restorer 7 and then input to the inter-frame spread signal averaging processor 4, the error of the spread signal of the entire frame can be almost eliminated.

Next, another embodiment of the code estimation method according to the present invention will be described. FIG. 8 shows a flowchart of another embodiment of the code estimation method according to the present invention. As shown in the figure, this embodiment is a code estimation method for receiving a direct spreading wave whose spreading code is unknown, converting the direct spreading wave into a baseband signal, and then at least estimating the spreading code. First, auto-correlation is performed with the correlation width of a predetermined signal section while sliding the correlation position little by little with respect to the baseband signal, and when the integrated value of the absolute value of the variation of the correlation value is smaller than the predetermined value, the same frame is obtained. Is detected and the frame length is detected (step 2).
01).

Subsequently, based on the frame length detection result in step 201, the baseband signal
Using the first frame as a correlation criterion, all the frames from the first frame to the nth frame are correlated with the first frame, and a change point of the correlation value is added. Is extracted as the information symbol change point of the first frame, and the point at which the addition result of
By estimating the information symbol in the frame and inverting the sign of the received signal so as to cancel the information symbol, it is determined that only the spread code information is left. The spread signal of each frame is obtained in the same manner as described above (step 202).

Subsequently, the spread signals of all the frames reconstructed in step 202 are integrated into chips, and the addition result obtained by adding in all the frames is subjected to code determination for each chip unit, and the spread signals are averaged and spread. Output as a code (step 203). Subsequently, the spread signals of all frames are restored again in the same manner as in step 202 (step 204).
Finally, after integrating the spread signals of all the frames that have been re-restored into chips, the addition result obtained by adding the results for all frames is sign-determined for each chip, and the spread signals are averaged and output as the final spread code. (Step 205). According to the code estimating method of this embodiment, the same effects as those of the code estimating apparatus shown in FIG. 7 can be obtained.

The present invention is not limited to the above embodiment, and various other modified examples can be considered.
For example, in the code estimating apparatus of the present invention shown in FIGS. 1 and 7, whether the frame spread signal decoders 2, 3 and the inter-frame spread signal averaging processor 4 are provided after the correlation variation detection type frame correlation detector 1 Or a frame spread signal restorer 5,
7. By providing the inter-frame spread signal averaging processors 6 and 4, even if a plurality of (not necessarily integer) information symbols are included in one frame, the spread signal can be restored with high accuracy. However, a brute force code correlator 12 may be provided at the next stage of the correlation fluctuation detection type frame correlation detector 1 as in the conventional apparatus. In this case, it is not expected that a spread signal can be restored with high accuracy. However, the correlation variation detection type frame correlation detector 1 slides the correlation position little by little with respect to the baseband signal and autocorrelates with the correlation width of a predetermined signal section. When the integral value of the absolute value of the variation of the correlation value is smaller than a predetermined value, it is determined that the same frame has appeared and the frame length is detected.
Even when a plurality of information symbols (not necessarily integers) are included in one frame of the unknown spreading code, an effect unique to the present invention that the frame length can be analyzed can be obtained.

In the above embodiment, the frame length is detected by the correlation fluctuation detection type frame correlation detector 1 on the assumption that the frame length of the spread modulation signal whose unknown spreading code is unknown is also unknown. If, for some reason, the spreading code is unknown, and the frame length of the spread modulated signal is known, the information of the known frame length input from the outside or the information of the known frame length stored in advance is used. Thus, the spread signal restoring operation may be performed by the first frame spread signal restorer 2 or the first frame spread signal restorer 5, and in this case, the correlation fluctuation detection type frame correlation detector 1 can be omitted. Also in this case, the effect unique to the present invention is obtained in that the spread code can be restored even when a plurality of (not necessarily integer) information symbols are included in one frame.

[0071]

As described above, according to the present invention,
It has the following features. (1) The autocorrelation is performed with a correlation width of a predetermined signal section while sliding the correlation position little by little with respect to the baseband signal. If the integrated value of the absolute value of the variation of the correlation value is smaller than the predetermined value, it is determined that the same frame has appeared. Since the frame length is determined and determined, the frame length can be analyzed even when a plurality of (not necessarily an integer) information symbols are included in one frame. (2) The autocorrelation between the frames is performed over a plurality of frames at the same corresponding position in the frame with the correlation width of the entire frame length, the change point of the information symbol is detected, the information symbol component is removed, and Since only the signal component is restored, the spread code can be restored even when a plurality of (not necessarily integer) information symbols are included in one frame. (3) Since the inter-frame signal averaging process is performed on the restored signals of the spread codes, a spread code with a good S / N can be restored even for a received signal with a bad S / N. (4) A code sequence is obtained by averaging spread signals between frames to obtain a code sequence irrespective of the nature of the code. Therefore, regardless of whether the code is a linear code or a nonlinear code, a spread code sequence is obtained. Can be estimated.

[Brief description of the drawings]

FIG. 1 is a block diagram of an embodiment of the device of the present invention.

FIG. 2 is an explanatory diagram of signal processing of a first frame information symbol change point detector in FIG. 1;

3 is an explanatory diagram of signal processing of a first frame inter-change point sign inverter in FIG. 1; FIG.

FIG. 4 is an explanatory diagram of signal processing of a spread signal decompressor for the second and subsequent frames in FIG. 1;

FIG. 5 is an explanatory diagram of signal processing of an inter-frame spread signal averaging processor in FIG. 1;

FIG. 6 is a flowchart of an embodiment of the method of the present invention.

FIG. 7 is a block diagram of another embodiment of the device of the present invention.

FIG. 8 is a flowchart of another embodiment of the method of the present invention.

FIG. 9 is a block diagram illustrating an example of a conventional code estimation device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Correlation fluctuation detection type frame correlation detector 2 First frame spread signal restorer 3 Second frame or later spread signal restorer 4, 6 Interframe spread signal averaging processor 5 First frame spread signal restorer 7 Second Frame spread signal reconstructor 21 First frame information symbol change point detector 22 First frame inter-change point sign inverter 31 Second frame and subsequent information symbol change point detector 32 Second frame and later inter-change point sign inverters 51 and 71 Frame information symbol change point detector 52, 72 Sign inverter between frame change points

Claims (20)

[Claims] 1. A direct spreading wave having an unknown spreading code is received,
A code estimating device for at least estimating the spreading code after converting the direct spread wave into a baseband signal, wherein autocorrelation is performed with a correlation width of a predetermined signal section while sliding a correlation position little by little with respect to the baseband signal. Therefore, when the integrated value of the absolute value of the variation of the correlation value is smaller than a predetermined value, it is determined that the same frame has appeared and a correlation variation detection type frame correlation detector for detecting a frame length is provided. apparatus. 2. A code estimating apparatus for receiving a direct spreading wave whose spreading code is unknown, converting the direct spreading wave into a baseband signal, and then estimating at least the spreading code, comprising: A first frame spread signal decompressor for canceling a signal component of an information symbol from a signal of a first frame to raise only a signal component of the spread code with respect to the baseband signal; A spread signal restored from a first frame by a 1-frame conversion signal restorer is received as an input, and a signal component of an information symbol is canceled from a signal of the baseband signal after a second frame, so that only a signal component of the spread code is removed. A second frame or later spread signal reconstructor to be raised, and the first frame reconstructed by the first frame spread signal reconstructor.
After the chip integration of the spread signal of the frame and the spread signal of the second and subsequent frames restored by the spread signal restorer for the second and subsequent frames, the addition result obtained by adding in all the frames is obtained for each chip. A code estimating apparatus comprising: an inter-frame spread signal averaging processor that performs code determination and outputs a spread code. 3. A code estimating apparatus for receiving a direct spreading wave whose spreading code is unknown, converting the direct spreading wave into a baseband signal, and at least estimating the spreading code, wherein the baseband signal is The autocorrelation is performed with the correlation width of the predetermined signal section while sliding the correlation position little by little.If the integrated value of the absolute value of the fluctuation of the correlation value is smaller than the predetermined value, it is determined that the same frame has appeared and the frame length is detected. A correlation variation detection type frame correlation detector, and based on the detection result of the frame length, cancels out the signal component of the information symbol from the signal of the first frame with respect to the baseband signal, thereby raising only the signal component of the spread code. A first frame spread signal reconstructor, the baseband signal, and the first frame converted signal reconstructor from the first frame. A second and subsequent spread signal decompressor, which receives the restored spread signal as an input, cancels the signal component of the information symbol from the second and subsequent frames of the baseband signal, and raises only the signal component of the spread code; The first frame spread signal restored by the first frame spread signal restorer.
After the chip integration of the spread signal of the frame and the spread signal of the second and subsequent frames restored by the spread signal restorer for the second and subsequent frames, the addition result obtained by adding in all the frames is obtained for each chip. A code estimating apparatus comprising: an inter-frame spread signal averaging processor that performs code determination and outputs a spread code. 4. A code estimating apparatus for receiving a direct spreading wave whose spreading code is unknown, converting the direct spreading wave into a baseband signal, and then estimating at least the spreading code, comprising: On the basis of this, a certain frame of the baseband signal is used as a correlation criterion, and all frames from the first frame to the nth frame are correlated with one frame as a correlation criterion. Summing, estimating the information symbol in the information symbol of one frame used as the correlation criterion based on the addition result, and canceling the information symbol, thereby restoring the spread signal information of one frame used as the correlation criterion. By sequentially switching and repeating the correlation reference frame for all frames from the first frame to the last frame, First to restore the scattered signal for each frame
After the chip integration of the spread signal of each frame restored by the first spread signal restorer, the addition result obtained by adding in all the frames is sign-determined for each chip. A code estimating apparatus comprising: a first inter-frame spread signal averaging processor that outputs an averaged spread code. 5. A code estimating apparatus for receiving a direct spreading wave whose spreading code is unknown, converting the direct spreading wave into a baseband signal, and at least estimating the spreading code, wherein the baseband signal is The autocorrelation is performed with the correlation width of the predetermined signal section while sliding the correlation position little by little.If the integrated value of the absolute value of the fluctuation of the correlation value is smaller than the predetermined value, it is determined that the same frame has appeared and the frame length is detected. A correlation variation detection type frame correlation detector, and based on the detection result of the frame length, one frame of the baseband signal is used as a correlation criterion, and all frames from the first frame to n frames are used as a correlation criterion. A correlation between one frame and one frame is obtained, and a change point of the correlation value is added. Estimating the information symbols in the broadcast symbol and canceling the information symbols to restore the spread signal information of one frame as the correlation criterion means that the frames as the correlation criterion are all from the first frame to the last frame. By sequentially switching and repeating the frames, a first spread signal decompressor for restoring the spread signals of all the frames for each frame, and a chip integration of the spread signal of each frame restored by the first spread signal decompressor And a first inter-frame spread signal averaging processor that outputs a result of addition obtained by adding in all frames as a spread code obtained by performing code determination and averaging for each chip unit. Estimation device. 6. A signal output from the first inter-frame spread signal averaging processor is received as a temporary decision spreading code,
A second spread signal decompressor for canceling the signal component of the information symbol for every frame and restoring only the signal component of the spread code and restoring the spread signal of the whole frame for each frame; and the second spread signal. 6. The code estimation according to claim 4, further comprising a second inter-frame spread signal averaging processor for averaging a restored spread signal of each frame output from the restorer and outputting a spread code. apparatus. 7. The first frame spread signal decompressor includes a plurality of frames between frames at the same corresponding position in the frame using the first frame of the baseband signal as a correlation reference in a correlation width of a signal section of a full frame length. A first frame information symbol change point detector for detecting autocorrelation, detecting a position where the sign of the correlation value is inverted, and determining a position commonly appearing in each frame as an information symbol change point of the first frame; A first frame inter-change point sign inverter for inverting all the signs of signals between any of the odd-numbered to even-numbered or even-odd-numbered information symbol change points from the start of one frame. The code estimation device according to claim 2 or 3, wherein 8. The second and subsequent frame spread signal decompressor receives as input the baseband signal and a spread code sequence reconstructed from the first frame after the information symbol component has been removed and the code has been determined. And a correlation value integration obtained by correlating the frames over a plurality of frames at the same corresponding position in the frame with the correlation width of the signal section of the entire frame length using the spread code string restored from the first frame as a correlation reference. An information symbol change point detector for outputting the position information of the peak and dip of the second and subsequent frames;
A code invertor between second and subsequent frames for inverting all the signs of the baseband signals in the second and subsequent frames in the dip section from the peak of the correlation value integration value from the second and subsequent information symbol change point detector; The code estimating apparatus according to claim 2, wherein the code estimating apparatus comprises: 9. The first spread signal decompressor uses one frame of the baseband signal as a correlation criterion based on the detection result of the frame length, and performs processing on all frames from the first frame to n frames. A correlation between one frame as a correlation criterion is obtained, a change point where the sign of the correlation value is inverted is detected, and a position commonly appearing in each frame is defined as an information symbol change point of one frame as a correlation criterion. The information symbol change point detector to be determined and all the signs of the signals between any of the information symbol change points from the odd number to the even number or from the even number to the odd number from the start of one frame as the correlation criterion. It consists of an inter-change-point sign inverter to be inverted, and operates by the information symbol change-point detector and the inter-change point sign inverter.
6. The code estimating apparatus according to claim 4, wherein a spread signal of all frames is restored for each frame by sequentially switching and repeating a frame as a correlation reference for all frames from the first frame to the last frame. . 10. The second spread signal reconstructor receives a signal output from the first inter-frame spread signal averaging processor as a temporary decision spreading code, and uses the temporary decision spreading code as a correlation reference, An information symbol change point detector that outputs position information of the peak and dip of the integrated value of the correlation value obtained by correlating the frames over a plurality of frames at the same corresponding position in the frame with the correlation width of the signal section of the entire frame length. 7. An inter-change point sign inverter for inverting all signs of signals of respective frames in a section from a peak to a dip of the correlation value integrated value from the information symbol change point detector. A code estimating device as described in the above. 11. A code estimating method for receiving a direct spread wave whose spreading code is unknown, converting the direct spreading wave into a baseband signal, and then estimating the spreading code at least. The autocorrelation is performed with the correlation width of the predetermined signal section while sliding the correlation position little by little.If the integrated value of the absolute value of the fluctuation of the correlation value is smaller than the predetermined value, it is determined that the same frame has appeared and the frame length is detected. A code estimating method comprising the steps of: 12. A code estimating method for receiving a direct spreading wave whose spreading code is unknown, converting the direct spreading wave into a baseband signal, and then estimating at least the spreading code, comprising: A first step of canceling a signal component of an information symbol from a signal of a first frame to raise only a signal component of the spread code with respect to the baseband signal, and restoring from the first frame by the first step A second step of, based on the spread signal, canceling a signal component of an information symbol from a signal of the second and subsequent frames of the baseband signal to raise only a signal component of the spread code; Chip integration of the spread signal of the first frame and the spread signal of the second and subsequent frames restored in the second step. And a third step of performing code determination on the result of addition performed on all the frames for each chip and outputting the result as a spread code. 13. A code estimating method for receiving a direct spread wave whose spreading code is unknown, converting the direct spreading wave into a baseband signal, and then estimating at least the spreading code. Auto-correlation is performed with the correlation width of the predetermined signal section while sliding the correlation position little by little.If the integrated value of the absolute value of the fluctuation of the correlation value is smaller than the predetermined value, it is determined that the same frame has appeared and the frame length is detected. A first step of performing, based on a frame length detection result obtained in the first step, canceling out a signal component of an information symbol from a signal of the first frame with respect to the baseband signal, thereby removing only a signal component of the spreading code. Based on the spread signal restored from the first frame by the second step, A third step of canceling the signal component of the information symbol from the signal of the second and subsequent frames of the signal so as to raise only the signal component of the spreading code; and the spread signal of the first frame restored in the second step. After chip integration of the spread signals of the second and subsequent frames restored in the third step, the addition result obtained by adding in all frames is code-determined for each chip and output as a spread code. And a fourth step. 14. A code estimation method for receiving a direct spreading wave whose spreading code is unknown, converting the direct spreading wave into a baseband signal, and then at least estimating the spreading code, comprising the steps of: On the basis of this, a certain frame of the baseband signal is used as a correlation criterion, and all frames from the first frame to the nth frame are correlated with one frame as a correlation criterion, and a change point of the correlation value is determined. Summing, estimating the information symbol in the information symbol of one frame used as the correlation criterion based on the addition result, and canceling the information symbol, thereby restoring the spread signal information of one frame used as the correlation criterion. By sequentially switching and repeating the correlation reference frame for all frames from the first frame to the last frame, First to restore the spread signal for each frame
And a step of chip-integrating the spread signal of each frame restored in the first step, adding the result of addition for all frames, and performing code determination for each chip and outputting the result as a spread code. 2. A code estimating method comprising: 15. A code estimation method for receiving a direct spreading wave whose spreading code is unknown, converting the direct spreading wave into a baseband signal, and then estimating the spreading code at least. The autocorrelation is performed with the correlation width of the predetermined signal section while sliding the correlation position little by little.If the integrated value of the absolute value of the fluctuation of the correlation value is smaller than the predetermined value, it is determined that the same frame has appeared and the frame length is detected. A first step of performing, based on the detection result of the frame length, one frame having the baseband signal as a correlation criterion, and one frame as a correlation criterion for all frames from the first frame to n frames. The correlation between the frames is obtained, and the change point of the correlation value is added. Reconstructing one frame of spread signal information based on the correlation criterion by estimating the information symbol and canceling the information symbol, sequentially switches the frame used as the correlation criterion for all frames from the first frame to the last frame. A second step of restoring the spread signals of all frames for each frame by repeating the above steps, and adding the spread signals of each frame restored in the second step in all frames after chip integration. And a third step of judging the addition result on a chip-by-chip basis and outputting the result as a spread code. 16. A signal obtained in the third step is received as a tentatively determined spreading code, and a signal component of an information symbol is canceled for each frame for all frames, and only a signal component of the spreading code is raised to generate a whole. The method further includes a fourth step of restoring the spread signal of the frame, and a fifth step of averaging the restored spread signal of each frame restored in the fourth step and outputting a spread code. The code estimation method according to claim 14 or 15, wherein 17. The method according to claim 17, wherein the second step is a step of calculating an autocorrelation between the frames over a plurality of frames at the same corresponding position in the frames by using the first frame of the baseband signal as a correlation criterion using a correlation width of a signal section of a full frame length. Taking a position where the sign of the correlation value is inverted, and determining a position that appears in each frame in common as an information symbol change point of the first frame; and 13. The method according to claim 12, further comprising the step of inverting all the signs of the signals between the even-numbered and odd-numbered information symbol transition points.
Or the code estimation method according to 13. 18. The method according to claim 3, wherein the third step receives, as inputs, the baseband signal and a spread signal sequence restored from the first frame after the information symbol component is removed and the code is determined. With the spread signal sequence restored from the frame as a correlation criterion, the peak of the correlation value integrated value obtained by taking the correlation between frames over a plurality of frames at the same corresponding position in the frame with the correlation width of the signal section of the entire frame length 2. The method according to claim 1, further comprising: outputting dip position information; and inverting all signs of the baseband signals of the second and subsequent frames in the dip interval from the peak of the correlation value integrated value.
18. The code estimation method according to 2, 13, or 17. 19. The method according to claim 19, wherein, based on a detection result of the frame length in the first step, one frame of the baseband signal is used as a correlation criterion, and all frames from the first frame to n frames are used. Take a correlation between one frame and a frame as a correlation criterion,
A change point determining step of detecting a change point where the sign of the correlation value is inverted, and determining a position that appears in each frame as an information symbol change point of one frame based on the correlation reference; From the start of, from the odd number to the even number or from the even number to the odd number, the sign inversion step of inverting all the signs of the signal between any of the information symbol change points, and the change point determination step, 16. The code estimating method according to claim 14, wherein the operation according to the sign inversion step is sequentially switched and repeated for all frames from the first frame to the last frame as a correlation reference frame. 20. The fourth step comprises: receiving the signal obtained in the third step as a tentatively determined spreading code; using the tentatively determined spreading code as a correlation criterion; Outputting the position information of the peak and dip of the correlation value integrated value obtained by correlating the frames over a plurality of frames at the same corresponding position within, and each frame in the section from the peak of the correlation value integrated value to the dip 17. The code estimating method according to claim 16, further comprising the step of inverting the signs of all the signals.