JP2000151528A - Identification system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To surely identify a transmission station even under a highly noisy environment or in the case of large fluctuation in a transmission line in the identification system in a system that uses a plurality of carriers to conduct transmission. SOLUTION: The identification system is provided with an adjacent carrier pair arithmetic means 120 that makes an arithmetic operation with adjacent carrier pairs of a received subcarrier group in a configuration that a plurality of transmission stations have different identification information, each identification information is identified through combinations of a plurality of carriers and adjacent carriers that are transmitted are formed in pairs. The correlation is calculated after the arithmetic operation. Thus, a transmission station can surely be identified under highly noisy environment or in the case of large fluctuation in a transmission line and the system with high reliability can be built up.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a transmission system using a plurality of carriers, and more particularly to an identification device for estimating a transmitting station from a received signal in a single frequency network in which the transmitting station transmits the same contents from a plurality of points. .

[0002]

2. Description of the Related Art Heretofore, there are few discriminating apparatuses in which the configuration is particularly mentioned, and the configuration of a signal on a transmitting side is generally considered to have the following structure.

FIG. 12 is a conceptual diagram showing a conventional transmission form of transmitting station information on a plurality of carriers. In FIG.
(A) shows the state of each subcarrier in a certain transmission time when transmission is performed using a plurality of carriers. (B) shows the state of information assigned to a certain transmitting station in the state of (a). Only the carrier at the position indicated by the solid line is transmitted, and no signal is transmitted at the position indicated by the dotted line. Assuming that all the subcarriers are n, by transmitting only m among them, the transmitting stations of _n C _m stations are distinguished. However, when the correlation is obtained on the receiving side, if the value of m is too large, the difference between the correlation values cannot be made so large that the identification becomes difficult. Therefore, m is not usually set to a very large number. It is an object of the identification device to distinguish and determine the m identification signals assigned in this way on the receiving side.

FIG. 13 shows the structure of a conventional general discriminating apparatus. The discriminating symbol extracting means 101 extracts a transmission symbol containing a transmitting station discriminating signal from a received signal 110, and a sub-symbol is extracted from the symbol. Subcarrier extracting means 102 for extracting carrier information, source information storing means 106 for storing source information in advance, and correlation calculating means 103 for calculating a correlation from the source information and the position of the extracted subcarrier. And maximum value detecting means 104 for detecting the largest one from the calculated correlation values, and transmission source determining means 10 for determining the transmitting station from the calculated maximum value.
And 5.

[0005]

In general, when transmission is performed using a single frequency network, identification of a transmitting station is performed so that it can be effectively used for control of a receiver and estimation of a receiving position. Becomes possible. Therefore, in the identification device, reliable identification of the transmitting station is required.

SUMMARY OF THE INVENTION It is an object of the present invention to reliably identify a transmitting station even in an environment with a large amount of noise or a large fluctuation of a transmission line.

[0007]

According to the present invention, a plurality of transmitting stations have different identification information, the identification information is identified by a combination of a plurality of carriers, and the transmitted carriers are adjacent to each other. When a configuration is made such that a pair is formed, adjacent carrier pair calculating means for performing a calculation in advance on adjacent carrier pairs of the received sub-carrier group is provided, and then the correlation is calculated.

[0008] This makes it possible to reliably identify the transmitting station even in an environment with a large amount of noise or a large fluctuation in the transmission path.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention according to claim 1 of the present invention is directed to a system for transmitting data using a plurality of carriers, and when a transmission system is constituted by a single frequency network, a plurality of carriers are provided. Means for extracting a symbol to be identified when the transmitting station has different identification information, the identification information is identified by a combination of a plurality of carriers, and the adjacent carriers to be transmitted are the same signal, Means for decomposing into sub-carriers represented by the above, adjacent carrier pair calculating means for performing pre-operation on adjacent carrier pairs of the decomposed sub-carrier group, and holding a combination of sub-carriers of the transmitting station known in advance. Means for storing source information to be stored, means for calculating a correlation with respect to a combination of the source information and the calculation result of the adjacent carrier pair, and extracting a maximum value from the calculated correlation values. This is an identification device configured to include a maximum value detecting unit that performs transmission and a source determining unit that determines a transmission source from the extracted maximum value, and effectively utilizes a condition that adjacent subcarriers are the same signal. This has the effect that the transmitting station can be reliably identified even during reception under bad conditions.

The invention according to claim 2 is the discriminating apparatus according to claim 1, wherein the adjacent carrier pair calculating means adds the power of each subcarrier, and the power addition of each of the adjacent carrier pairs. Has the effect of increasing resistance to transmission line fluctuations.

The invention according to claim 3 is the identification device according to claim 1, wherein the adjacent carrier pair calculating means multiplies the power of each subcarrier by multiplying the power of each of the adjacent carrier pairs. Thereby, an unnecessary subcarrier can be removed.

According to a fourth aspect of the present invention, there is provided the identification apparatus according to the first aspect, wherein the adjacent carrier pair calculating means performs vector correlation of each subcarrier. It has the effect of becoming stronger against unnecessary carrier signals.

According to a fifth aspect of the present invention, the means for calculating the correlation performs the scalar correlation after calculating the vector power of each subcarrier. Exerts a similar effect.

According to a sixth aspect of the present invention, in the identification apparatus of the fourth aspect, the means for calculating the correlation calculates the vector power after performing the vector addition. Exhibit the same effect.

[0015] The invention according to claim 7 is the invention according to claims 1 to 6.
A receiving device having the identification device according to any of the above,
By utilizing the advantage of the identification device according to any one of the first to sixth aspects, an effect is obtained that a reception device with an improved reception state can be obtained.

[0016] The invention according to claim 8 is the invention according to claims 1 to 6.
A transmission / reception system having the identification device according to any one of the first to sixth aspects, and a highly reliable system utilizing the advantages of the identification device according to any one of the first to sixth aspects can be constructed.

Hereinafter, an embodiment of the present invention will be described with reference to FIG.
This will be described with reference to FIG. (Embodiment 1) FIG. 1 is a block diagram showing a basic configuration of an identification apparatus according to the present embodiment. In FIG. 1, reference numeral 101 denotes a transmission symbol including an identification signal of a transmitting station from a reception signal 110. , A sub-carrier extracting means for extracting sub-carrier information from the symbol, a source information storing means for storing source information in advance, and a source information storing and extracting means for storing the source information. Correlation calculating means for calculating a correlation from the calculated position of the sub-carrier, 104 is maximum value detecting means for detecting the largest one from the calculated correlation values, and 105 is for determining the transmitting station from the calculated maximum value. The transmission source determination means performs pre-computation processing on the subcarriers extracted by 102 by the adjacent carrier pair processing means 120, thereby providing resistance to disturbance on the transmission path. It is improving.

FIG. 2 schematically shows the state of the subcarrier at that time. (A) is an example of an effective transmission subcarrier for general transmission station identification. (B) is an example of a transmission sub-carrier of the transmitting station identification information, which is characterized in that the transmission sub-carrier exists in a pair with an adjacent sub-carrier. The identification information transmitted in this way is observed by the receiving side 101 and 102 as a subcarrier. Here, since the position of the subcarrier pair is known in advance, it is possible to perform arithmetic processing on the -pair. Therefore, the maximum value is detected by performing a correlation calculation with the transmission station original information stored in advance for the one that has been appropriately processed by 120,
Determine the transmitting station.

According to the present embodiment, it is possible to effectively utilize the condition that adjacent subcarriers are the same signal, and to reliably identify a transmitting station even when receiving under bad conditions.

(Embodiment 2) FIG. 3 shows a first configuration in the vicinity of the adjacent carrier pair processing means of the discriminating apparatus according to the present embodiment. Up to the output. FIG.
, 112 is an extracted subcarrier input, 121 is a means for calculating the power of each subcarrier, 122 is a means for adding power as a subcarrier pair, 124 is a storage means for storing source information as a subcarrier pair, 123 Means for calculating the scalar correlation of the source information stored as the subcarrier pair with and without the subcarrier pair power calculated by 122 and the source information, and 113 is the result of taking the scalar correlation. Since the correlation value is calculated as the sum between adjacent subcarriers in the processing unit for the subcarrier pair, the resistance to disturbance is improved as compared with the case of a single subcarrier.

(Embodiment 3) FIG. 4 shows a second configuration near the adjacent carrier pair processing means of the discriminating apparatus according to the present embodiment. Up to the output. FIG.
In this embodiment, most of the components are the same as those shown in FIG. 3 except that a subcarrier pair multiplying means 125 is provided instead of the subcarrier pair adding means 122.

FIG. 5 is a diagram showing the concept of the processing by the configuration of FIG. By configuring the processing unit for the subcarrier pair as shown in FIG. 4, the correlation value is calculated as the product between the adjacent subcarriers, so that the unnecessary signal that enters due to external factors as shown in FIG. In addition, it is possible to improve resistance to an unnecessary signal generated inside.

(Embodiment 4) FIG. 6 shows a third configuration near the adjacent carrier pair processing means of the discriminating apparatus according to the present embodiment. Up to the output. FIG.
, Most of the components are the same as those shown in FIG. 3, but instead of the subcarrier power calculating means 121 and the subcarrier pair adding means 122, a subcarrier pair vector correlation calculating means 126 and a vector power calculating means 127 are provided. The feature is that it is provided.

FIG. 7 is a diagram showing the concept of the processing by the configuration of FIG. By configuring the processing unit for the subcarrier pair as shown in FIG. 6, since the correlation value is calculated as the vector correlation between adjacent subcarriers, there is no need to jump in due to external factors as shown in FIG. Resistance to signals and unnecessary signals generated inside can be improved.

Further, such a configuration is different from (Embodiment 3) in that not only the scalar correlation calculation of the magnitude of the vector product is performed but also the case where the transmission subcarrier undergoes phase rotation at the time of reception is as follows. It has a great effect like

FIG. 8 is a diagram showing a different concept of the processing by the configuration of FIG. 6 from the above. 8A shows a transmission sub-carrier, FIG. 8B shows a state in which the transmission sub-carrier (a) has undergone phase rotation at the time of reception, and FIG. 8C shows a state in which the received signal in FIG.

The cause of the phase rotation between adjacent subcarriers may be, for example, an error when the receiving side determines the symbol time of the orthogonal frequency division multiplexed signal, or interference at the time of simultaneous reception of multipath signals. However, in general, even in a wideband received signal, the frequency interval between adjacent subcarriers is considered to be small, so that the rotation phase between adjacent subcarriers may be considered to have regularity even when considering the fluctuation of the transmission path (b). . Then, the signal after the adjacent subcarrier vector correlation calculation is usually observed as a substantially constant vector as shown in (c). Further, as described above, when an unnecessary signal enters only one of the adjacent pairs, the unnecessary signal is removed.

Further, since a function of obtaining a constant vector as shown in FIG. 8C is provided, by adding the vector after each adjacent pair operation, it is possible to further improve the resistance to disturbance. . The configuration at that time is shown in FIG.

FIG. 9 shows a different configuration near the adjacent carrier pair processing means of the discriminating apparatus, and corresponds to the range from the input of the adjacent carrier pair processing means 120 to the output of the correlation calculation means 103 in FIG.

The difference between FIG. 6 and FIG. 9 is that the former calculates the power (absolute value) immediately after calculating the adjacent pair vector correlation and then calculates the correlation by referring to the information of the transmission source. The point is that the signal after the adjacent pair vector correlation calculation is vector-added based on the subcarrier position information of the transmission source (128) and then the magnitude is calculated (129).

In these configurations, the former has an advantage that the amount of calculation is small, and the latter has an advantage that resistance to disturbance is large.

(Embodiment 5) FIG. 10 is a diagram showing a receiving apparatus having the identification device 205 described in the above embodiment as a means. In FIG. 12, reference numeral 210 denotes an RF modulated signal input modulated at a high frequency; 201, a reception front-end unit serving as frequency conversion means for converting the input modulated signal into a frequency band which can be easily handled; 202, a demodulation unit for extracting data from the modulated signal , 203 is a data reproducing unit for converting into meaningful data, 204 is an information output unit for outputting data, 205 is an identification device, and 206 is an information processing unit.

The information of the transmitting station obtained by the identification device 205 is useful for improving the reception state by judging the reception state and returning the information to the demodulation unit 202. If the position of the transmitting station is known in advance, the output of the identification device 205 is processed by the information processing unit 206, so that the information can be used as geographical information of the receiving area.
By outputting it as the data signal 211, it can be displayed on an external display means or the like (not shown).

(Embodiment 6) FIG. 11 is a diagram showing a transmitting / receiving system including the receiving device described in (Embodiment 5). In FIG. 13, reference numeral 212 denotes an information input, 213 denotes an RF modulation signal output, 311 denotes a receiving device, and 310 denotes a transmitting device.

The transmitting device 310 generates a signal to be transmitted to the receiving device 311 including the identification device.

By constructing the transmission / reception system having such a configuration, it is possible to construct a highly reliable system utilizing the advantages of the identification device according to the above-described embodiment.

[0037]

As described above, according to the present invention, when a transmission system is constituted by a single frequency network in a system intended to perform transmission using a plurality of carriers, a plurality of transmission stations are different. An adjacent carrier pair calculating means is provided which has identification information, and which is identified by a combination of a plurality of carriers and in which adjacent carrier waves to be transmitted are the same signal, and performs an operation in advance on adjacent carrier pairs of the subcarrier group. This has an advantageous effect that the transmitting station can be reliably identified even in an environment with a large amount of noise or a large fluctuation in the transmission path.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a configuration of an identification device according to an embodiment of the present invention;

FIG. 2 is a conceptual diagram showing a state of transmission of a subcarrier used in the present invention.

FIG. 3 is a block diagram showing a configuration near a carrier pair processing means in the identification device according to the embodiment of the present invention;

FIG. 4 is a block diagram showing a configuration in the vicinity of a carrier pair processing unit in the identification device according to the embodiment of the present invention;

FIG. 5 is a conceptual diagram showing processing by an identification device using the configuration of FIG. 4 in one embodiment of the present invention;

FIG. 6 is a block diagram showing a configuration near a carrier pair processing unit in the identification device according to the embodiment of the present invention;

FIG. 7 is a conceptual diagram showing processing by an identification device using the configuration of FIG. 6 in one embodiment of the present invention.

FIG. 8 is a conceptual diagram showing processing by an identification device using the configuration of FIG. 6 in one embodiment of the present invention;

FIG. 9 is a block diagram showing a configuration near a carrier pair processing unit in the identification device according to the embodiment of the present invention;

FIG. 10 is a block diagram showing a configuration of a receiving device using the identification device according to one embodiment of the present invention;

FIG. 11 is a configuration diagram of a transmission / reception system including a reception device using an identification device according to an embodiment of the present invention.

FIG. 12 is a conceptual diagram of conventional general multi-carrier transmission and sub-carrier transmission as an identification signal.

FIG. 13 is a configuration block diagram showing a conventional identification device.

[Explanation of symbols]

 Reference Signs List 101 identification symbol extraction means 102 subcarrier extraction means 103 correlation calculation means 104 maximum value detection means 105 source determination means 106, 124 source information storage means 110 orthogonal frequency division multiplexed signal input including identification signal 111 identification transmission station information output 112 Subcarrier input 113 Correlation value output 120 Adjacent subcarrier pair processing means 121 Subcarrier power (absolute value) calculation means 122 Subcarrier pair addition means 123 Scalar correlation calculation means 125 Subcarrier pair multiplication means 126 Subcarrier pair vector correlation calculation means 127 Vector power calculation means 128 Vector addition means 129 Vector power (absolute value) calculation means 201 Receive front-end signal processing means 202 Modulation signal demodulation means 203 Data reproduction means 204 Information output means 205 Identification device 206 Information processing means 21 RF modulated signal input 211 information output 212 information input 213 RF modulated signal output 310 transmitting unit 311 receiving unit

 ────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Morikazu Sagawa 3-10-1 Higashi-Mita, Tama-ku, Kawasaki-shi, Kanagawa F-term in Matsushita Giken Co., Ltd. 5K022 AA01 AA12 AA22

Claims (8)

[Claims] In a system for transmitting using a plurality of carriers, when a transmission system is configured by a single frequency network, a plurality of transmitting stations have different identification information,
When the identification information is identified by a combination of a plurality of carriers and the adjacent carriers to be transmitted are the same signal, a means for extracting a symbol to be identified and a decomposition into subcarriers, which are representations of the identification symbol on the frequency axis. Means, an adjacent carrier pair calculating means for performing an operation in advance on adjacent carrier pairs of the decomposed subcarrier group, and a source information storage means for holding a combination of subcarriers of a transmitting station known in advance, Means for calculating a correlation with respect to the combination of the source information and the operation result of the adjacent carrier pair; maximum value detecting means for extracting a maximum value from the calculated correlation values; transmission from the extracted maximum value An identification device configured to include a transmission source determination unit that determines a source. 2. The identification device according to claim 1, wherein the adjacent carrier pair calculating means adds the power of each subcarrier. 3. The identification device according to claim 1, wherein the adjacent carrier pair calculating means multiplies the power of each subcarrier. 4. The identification device according to claim 1, wherein the adjacent carrier pair calculating means performs vector correlation of each subcarrier. 5. The apparatus according to claim 4, wherein the means for calculating the correlation performs the scalar correlation after calculating the vector power of each subcarrier. 6. The identification device according to claim 4, wherein the means for calculating the correlation calculates the vector power after performing the vector addition. 7. A receiving device comprising the identification device according to claim 1. 8. A transmission / reception system having the identification device according to claim 1.