JP4659306B2 - Information wireless transmission system and transmitter and receiver thereof - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an information wireless transmission system for wirelessly transmitting a program material collected from a transmitting station (such as a mobile studio or a coverage helicopter) arranged at an arbitrary position to a receiving station such as a repeater, a transmitting apparatus therefor, The present invention relates to a receiving device.
[0002]
[Prior art]
For news programs, etc., as a form of on-site coverage, the helicopter flies over the site, shoots the site from above, and sends it to the terrestrial repeater by radio as program material information to the broadcasting station (transmitting station) Live broadcasts that transfer and broadcast in real time are common. In addition, a mobile studio may be set up at an arbitrary location, and the live studio may be relayed live to a repeater or broadcast station by radio. When performing such wireless information transmission, it is necessary to adjust the direction of the antenna to the optimum direction on the receiving side in order to secure the communication line between the transmitting station and the receiving station. After capture, you must follow the changes thereafter.
[0003]
As a conventional method for adjusting the antenna directivity direction, position information is obtained using a GPS (Global Positioning System) on the transmission side, and this position information is obtained using wireless communication for communication independent of material transmission. The antenna pointing direction is adjusted based on the position information transmitted to the reception side administrator and received on the reception side.
[0004]
[Problems to be solved by the invention]
As described above, in the conventional information wireless transmission system, a communication line different from the information transmission is necessary for transmitting the antenna adjustment position information. When this communication line cannot be secured, There was a problem that information transmission became impossible.
[0005]
The present invention solves the above-mentioned problems, and can transmit the position information on the transmitting side for antenna adjustment on the receiving side without using a separate communication line for information transmission, and easily point the receiving antenna in the direction of arrival of radio waves. It is an object of the present invention to provide an information wireless transmission system that enables information transmission, and a transmitting apparatus and a receiving apparatus thereof.
[0006]
[Means for Solving the Problems]
In order to achieve the above object, an information wireless transmission system according to the present invention, when wirelessly transmitting main information from a transmitting station to a receiving station, transmits the position information of the transmitting station on the transmitting station side. A transmission signal is generated by multiplexing to a strong layer portion in a band, and the transmission signal is transmitted from the transmitting antenna to the space. The transmission signal from the transmitting station is received by the receiving antenna on the receiving station side, and the strong layer is transmitted. The position information transmitted by the unit is separated, and the receiving antenna is directed in the direction of arrival of the transmission signal based on the position information.
[0007]
Specifically, in the transmission apparatus arranged in the transmission station, the main information and the position information of the transmission station are encoded independently, and the transmission band has a strong hierarchy. And a multiplexing unit that divides the information into a weak layer part, assigns the position information encoded by the encoding processing means to the strong layer part, assigns the main information to the weak layer part, and multiplexes the output. Transmission processing means for performing modulation, frequency conversion to a radio frequency band, power amplification and transmission.
[0008]
As the multiplexing means, a predetermined carrier is a strong layer portion and the remaining carriers are weak layer portions, or a predetermined frequency region is a strong layer portion and the remaining frequency regions are weak layer portions. . Further, the strong layer portion and the weak layer portion are selected by the carrier modulation method or by the amplitude value.
[0009]
Further, in the receiving device arranged in the receiving station, a directional antenna that receives a transmission signal transmitted from the transmitting station, a signal received by the directional antenna is amplified, and a frequency is set to baseband. Reception processing means for converting and demodulating, separation means for separating the position information component from the received signal obtained by the reception processing means, and decoding means for decoding the position information from the position information component separated by the separation means, And antenna directivity control means for controlling the directivity direction of the directional antenna based on the position information decoded by the decoding means.
[0010]
With the configuration as described above, the transmitting side position information for antenna adjustment is transmitted in the strong layer part in the transmission band of the main information, so that the position information can be obtained even if the receiving antenna is not directed toward the moving body. Can be received, and the receiving antenna can be pointed and tracked in the optimum direction based on the received position information. As a result, it is not necessary to use a separate communication line for transmitting the transmission side position information for antenna adjustment.
[0011]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
[0012]
FIG. 1 shows the configuration of an information wireless transmission system according to the present invention. FIG. 1 (a) is a transmitting device provided on the transmitting station side such as a mobile body, and FIG. 1 (b) is a receiving station such as a relay vehicle. The structure of the receiving device provided in FIG. Here, an OFDM (Orthogonal Frequency Division Multiplexing) system is used as the transmission system.
[0013]
On the transmitting station side, its own position information is acquired by GPS or the like together with material information which is main information. In the transmission apparatus shown in FIG. 1A, the material information and the position information are subjected to error correction coding and interleaving processing independently from each other by the coding processing units 11a and 11b, and are supplied to the multiplexing processing unit 12. The
[0014]
In the multiplexing processing unit 12, the carrier modulation units 121a and 121b perform carrier modulation on the material information and the position information using different modulation schemes, assign them to predetermined carriers in the mapping processing unit 122, multiplex them, and then perform IFFT. (Inverse Fourier transform) The processing unit 123 converts the frequency domain to the time domain to generate a baseband OFDM signal. At this time, as a carrier modulation method adopted for each information, for example, a multi-value modulation method such as 16QAM or 64QAM is used for material information, whereas a position information is a modulation which is not easily affected by a transmission path failure such as BPSK or QPSK. Use the method.
[0015]
The baseband OFDM signal obtained by the multiplexing processor 12 is orthogonally modulated by the orthogonal modulator 13, frequency-converted to the RF band by the frequency converter 14, power amplified by the power amplifier 15, and transmitted. The signal is transmitted from the antenna 16 to the space. The transmission antenna 16 may be omnidirectional, but may be directional to ensure transmission gain. In this case, since the position of the receiving station is known in advance, it can be easily directed in that direction.
[0016]
On the receiving station side, radio waves from the transmitting station are captured by the receiving antenna 21 having directivity. The reception signal obtained by the reception antenna 21 is amplified by the low noise amplification unit 22, returned to the baseband OFDM signal by the frequency conversion unit 23, orthogonally demodulated by the orthogonal demodulation unit 24, and then transmitted to the separation processing unit 25. Supplied.
[0017]
Contrary to the transmission side, the separation processing unit 25 converts the received signal from the time domain to the frequency domain by an FFT (Fourier transform) processing unit 251, and separates it into main information and position information by a demapping processing unit 252. The carrier demodulation units 253a and 253b perform carrier demodulation. The demodulated main information and position information are subjected to deinterleave processing and error correction in the decoding processing units 26a and 26b, respectively, and then the main information is sent to the monitor system and the relay transmission system. Supplied to the unit 27.
[0018]
The antenna directing control unit 27 obtains the azimuth angle and elevation angle at which the transmitting station exists from the input position information, and directs the receiving antenna 21 to the angles.
[0019]
FIG. 2 shows an example of multiplexing the position information. Here, a specific carrier in the transmission band is assigned for position information transmission. The specific carrier may be dedicated to the position information. However, since a pilot signal for performing equalization processing on the receiving side is normally assigned to the specific carrier, the pilot signal itself may be modulated with the position information. Good. In this case, the problem of a decrease in main information transmission amount due to position information transmission can be avoided.
[0020]
FIG. 3 shows another example of multiplexing the position information. In this example, a specific frequency region in the transmission band is specified as a strong layer portion, and the position information is assigned thereto.
[0021]
That is, in the information wireless transmission system having the above configuration, the position information is multiplexed with the main information and transmitted, so there is no need to separately secure a communication line for transmitting the position information. In addition, since the location information is transmitted in a strong layer that is different from the main information, using a modulation method that is not easily affected by transmission path disturbances, only the location information can be received even if the receiving antenna is not accurately directed to the moving body. Based on this position information, the receiving antenna can be directed toward the transmitting station and can follow the position change.
[0022]
Therefore, according to the information wireless transmission system configured as described above, it is possible to acquire the transmitting side position information for antenna adjustment on the receiving side without using a separate communication line. It becomes possible to continuously track the main information transmission with high gain by tracking in the direction of arrival.
[0023]
In the above embodiment, the strong layer part for position information transmission and the weak layer part for main information transmission are selected by the carrier modulation method. However, the amplitude value of the position information transmission carrier is selected as the main information at the time of mapping processing. It is also possible to select by the amplitude value so as to be higher than the amplitude value of the transmission carrier.
[0024]
Moreover, although the case where OFDM was employ | adopted as a multiplex transmission system was demonstrated in the said embodiment, other multiplex transmission systems, such as CDM (Code Division Multiplexing), can be implemented similarly.
[0025]
【The invention's effect】
As described above, according to the present invention, when transmitting information, the transmitting side position information for antenna adjustment can be acquired on the receiving side without using a separate communication line, and the receiving antenna can be easily directed in the direction of arrival of radio waves. It is possible to provide an information wireless transmission system that enables information transmission, and a transmitter and a receiver thereof.
[Brief description of the drawings]
FIG. 1 shows an embodiment of an information wireless transmission system according to the present invention, where (a) is a transmission device provided in a transmission station, and (b) is a block diagram showing a configuration of a reception device provided in a reception station. .
FIG. 2 is a frequency characteristic diagram showing an example of multiplexing position information in the embodiment.
FIG. 3 is a frequency characteristic diagram showing another example of multiplexing position information in the embodiment.
[Explanation of symbols]
11a, 11b ... Coding processing unit 12 ... Multiplexing processing unit 121a, 121b ... Carrier modulation unit 122 ... Mapping processing unit 123 ... IFFT (inverse Fourier transform) processing unit 13 ... Orthogonal modulation unit 14 ... Frequency conversion unit 15 ... Power amplification Unit 16 ... Transmission antenna 21 ... Reception antenna 22 ... Low noise amplification unit 23 ... Frequency conversion unit 24 ... Orthogonal demodulation unit 25 ... Separation processing unit 251 ... FFT (Fourier transform) processing unit 252 ... Demapping processing units 253a, 253b ... Carrier Demodulator 26a, 26b ... Decoding processor 27 ... Antenna pointing controller

Claims (7)

In an information wireless transmission system that wirelessly transmits main information from a transmitting station to a receiving station,
On the transmitting station side, position information of the transmitting station is multiplexed with a strong layer within the transmission band of the main information to generate a transmission signal, and this transmission signal is sent from the transmitting antenna to space
The receiving station receives a transmission signal from the transmitting station by a receiving antenna, separates position information transmitted by the strong layer portion, and directs the receiving antenna in the direction of arrival of the transmission signal based on the position information An information wireless transmission system characterized by the above. Used in an information wireless transmission system that wirelessly transmits main information from a transmitting station to a receiving station, and in a transmitting device disposed in the transmitting station,
Encoding processing means for independently encoding the main information and the location information of the transmitting station;
A multiplexing unit that divides the transmission band into a strong layer part and a weak layer part, assigns the position information encoded by the encoding processing means to the strong layer part, and assigns and multiplexes the main information to the weak layer part;
A transmission processing means for modulating the output of the multiplexing means, converting the frequency to a radio frequency band, amplifying the power, and sending it;
A transmission device for an information wireless transmission system comprising: 3. The transmission apparatus for an information radio transmission system according to claim 2, wherein the multiplexing means sets a predetermined subcarrier as a strong layer portion and the remaining subcarriers as a weak layer portion. 3. A transmission apparatus for an information wireless transmission system according to claim 2, wherein said multiplexing means sets a predetermined frequency region as a strong layer portion and the remaining frequency region as a weak layer portion. 3. The transmission apparatus for an information wireless transmission system according to claim 2, wherein the strong layer portion and the weak layer portion are selected by a carrier modulation method. 3. The transmission apparatus for an information wireless transmission system according to claim 2, wherein the strong layer portion and the weak layer portion are selected by an amplitude value of a transmission carrier . Used data wireless transmission system according to claim 1, wherein a disposed Ru receiving apparatus to the receiving station,
A directional antenna for receiving a transmission signal transmitted from the transmission station;
A reception processing means for amplifying a signal received by the directional antenna, converting the frequency to a baseband, and demodulating;
Separating means for separating a position information component transmitted by the strong layer portion from a received signal obtained by the reception processing means;
Decoding means for decoding position information from the position information component separated by the separation means;
Antenna directivity control means for controlling the directivity direction of the directional antenna based on the position information decoded by the decoding means;
A receiver for an information wireless transmission system, comprising:

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