JP4017620B2 - Wireless redistribution system for terrestrial digital TV broadcasting - Google Patents

Description

  The present invention relates to a wireless redistribution system for terrestrial digital TV broadcasting.

  Japan's terrestrial digital TV broadcasting has started on December 1, 2003 in the three major metropolitan areas of Kanto, Chukyo, and Kinki. Terrestrial digital TV broadcasting uses OFDM (Orthogonal Frequency Division Multiplexing), which is resistant to multipath interference, and there is almost no multiplex image (ghost disturbance) generated in analog TV broadcasting, etc., and stable high image quality. Can receive. Terrestrial digital TV broadcasting is broadcast in the UHF band (470 to 770 MHz).

  As a form of receiving a terrestrial digital TV broadcast by a terrestrial digital TV receiver, there are generally the following forms.

(1) A terrestrial digital TV broadcast signal is received by an outdoor antenna. A terrestrial digital TV broadcast signal received by an outdoor antenna is distributed to each room by an antenna cable and guided to a TV terminal provided on the wall surface of each room. Then, the antenna terminal of the terrestrial digital TV receiver is connected to the TV terminal provided on the wall surface of each room via an antenna cable.
In such a receiving mode, it is necessary to connect the antenna terminal of the terrestrial digital TV receiver to the TV terminal provided on the wall surface by using an antenna cable, so that the beauty is impaired and the wiring is troublesome. There is. In addition, since the layout of the TV receiver is limited, there is a problem that the degree of freedom of the installation position of the TV receiver is hindered.

(2) Without installing an antenna on the rooftop (on the roof), install a UHF antenna (for example, UDMF62: made by Japan Antenna) on the eaves or veranda, and then pull the antenna cable indoors to receive digital terrestrial TV Connect directly to the antenna terminal of the machine.
Even in such a reception mode, it is necessary to draw the antenna cable into the room and connect it to the terrestrial digital TV receiver. This causes a problem in that the appearance is impaired and the wiring is troublesome. In addition, since the layout of the TV receiver is limited, there is a problem that the degree of freedom of the installation position of the TV receiver is hindered.

(3) The terrestrial digital TV broadcast signal is received by the indoor antenna connected to the terrestrial digital TV receiver.
In such a receiving mode, there is no restriction on the layout of the TV receiver due to the wiring of the antenna cable, but there is a problem that a radio wave blocking loss occurs in the room. In particular, the UHF band used for terrestrial digital TV broadcast signals has a larger attenuation loss when passing through buildings than the VHF band used for terrestrial analog TV broadcasts. There is a problem that the installation position is limited.

  Therefore, an indoor re-transmission system has been developed in which a terrestrial digital TV broadcast signal input indoors is amplified by a wireless transmitter and retransmitted wirelessly to a TV receiver (Japanese Patent Laid-Open No. 2004-128719, JP, 2004-12720, A). In this indoor retransmission system, UHF band terrestrial digital TV broadcast signals input indoors are amplified and retransmitted as they are without frequency conversion.

  In the frequency band of the UHF band, as will be described later, since the transmission output level of the wireless transmitter is limited to a very low level, there is a problem that the transmission distance is almost short distance transmission only.

  In addition, when both the direct broadcast radio wave transmitted from the broadcasting station and the retransmitted radio wave transmitted from the wireless transmitter are received and input from the indoor receiving antenna, the signal of the same frequency channel is input to the TV receiver. As a result, there is a case where interference cannot be received due to the interference of the same channel.

In order to prevent this, there is a problem that a device for preventing the deterioration of the terrestrial digital TV broadcast signal due to the interference with the same channel is separately required for the antenna and the circuit.
JP 2004-128719 A Japanese Patent Laid-Open No. 2004-12720

  Therefore, the present applicant can prevent the occurrence of interference interference on the same channel of the terrestrial digital TV broadcast signal by performing the frequency conversion on the transmitter side, and does not require the frequency conversion on the receiver side. A wireless redistribution system for TV broadcasting (not known at the time of this application) has been developed.

  Hereinafter, a wireless redistribution system for terrestrial digital TV broadcasting developed by the present applicant will be described.

  This wireless redistribution system is made using the following actual situations (1) and (2).

(1) As will be described later, in addition to the UHF band, the stationary TV receiver for terrestrial digital TV broadcasting includes a VHF_Low / High band (VHF1ch to VHF12ch), a VHF_MID band (C13ch to C22ch), and a VHF_SHB band (C23ch). ~ C63ch) are often designed to be received.

(2) Further, as described later, in the weak radio wave standard, the restriction on the electric field strength for the frequency band of 322 MHz or less and 150 GHz or more is looser than the restriction of the electric field strength for the frequency band of 322 MHz to 150 GHz.

  The wireless redistribution system for terrestrial digital TV broadcasting developed by the present applicant is capable of receiving VHF band TV broadcast signals in addition to UHF band TV broadcast signals, which are the frequency bands of terrestrial digital TV broadcast signals. A TV receiver, a redistribution transmitter, and a redistribution receiver are provided.

  The redistribution transmitter has a terrestrial digital TV broadcast signal of a desired viewing channel designated by a predetermined input means among terrestrial digital TV broadcast signals input from an outdoor antenna, and has a frequency of 322 MHz or less. In addition, the input digital terrestrial TV broadcast signal is frequency-converted in a batch so that the frequency is converted into the frequency of one specific empty channel in the VHF band, and the VHF band is specified among the obtained TV broadcast signals. Only the TV broadcast signal in the frequency band of one vacant channel is extracted, and the extracted TV broadcast signal is amplified and wirelessly transmitted.

  The receiver for redistribution receives and amplifies the signal transmitted from the transmitter, and then supplies it to the TV receiver. In the TV receiver, a specific vacant channel in the VHF band is selected, so that the terrestrial digital TV broadcast signal of the desired viewing channel designated by the user is broadcast.

  However, in the above-mentioned wireless redistribution system developed by the present applicant, the TV receiver side always selects one specific empty channel in the VHF band. However, there is a problem that it is difficult for the user to recognize.

  The present invention can prevent the occurrence of interference interference on the same channel of a terrestrial digital TV broadcast signal, eliminates the need for frequency conversion on the receiver side, and makes it easier to recognize the terrestrial digital TV broadcast channel being viewed. An object of the present invention is to provide a radio redistribution system for wave digital TV broadcasting.

  According to the first aspect of the present invention, in addition to the TV broadcast signal in the UHF band, which is the frequency band of the terrestrial digital TV broadcast signal, the TV receiver capable of receiving the TV broadcast signal in the VHF band, and the ground received by the outdoor antenna. For transmitting a digital terrestrial TV broadcast signal, converting the frequency of the input terrestrial digital TV broadcast signal, and then transmitting wirelessly, and inputting a desired channel for terrestrial digital TV broadcast to the transmitter and TV receiver A desired channel input means, and a receiver that receives and amplifies a signal transmitted from the transmitter and then supplies the signal to the TV receiver, and the transmitter receives the input digital terrestrial TV broadcast. Of the signals, the terrestrial digital TV broadcast signal of the desired viewing channel input by the desired viewing channel input means is set to a preset VHF band. Among the TV broadcast signals obtained by the frequency conversion means and the frequency conversion means obtained by the frequency conversion means for converting the frequency of the input digital terrestrial TV broadcast signals at once so as to be converted into the frequency of one specific empty channel. Filter means for extracting only a TV broadcast signal in a frequency band of a specific one vacant channel in the set VHF band, and transmission means for amplifying the TV broadcast signal extracted by the filter means and wirelessly transmitting the signal. The TV receiver includes means for displaying a desired viewing channel of the terrestrial digital TV broadcast inputted by the desired viewing channel input means.

  According to a second aspect of the present invention, in the radio terrestrial digital TV broadcast wireless redistribution system according to the first aspect, the frequency of one specific empty channel in the preset VHF band is in the VHF band of 322 MHz or less. It is characterized by the frequency of one specific empty channel.

  According to a third aspect of the present invention, in the wireless terrestrial digital TV broadcast wireless redistribution system according to the first or second aspect, the desired viewing channel input means desires to view or transmit to the transmitter and the TV receiver by radio or infrared. It is a remote control transmitter for transmitting a channel.

  According to a fourth aspect of the present invention, in the wireless terrestrial digital TV broadcast wireless redistribution system according to the first or second aspect, the desired viewing channel input means transmits the desired viewing channel to the transmitter by radio or infrared. A remote control transmitter and means for inputting a desired viewing channel sent from the remote control transmitter to the transmitter to the TV receiver via the transmitter and the receiver are provided.

  According to the present invention, it is possible to prevent the occurrence of interference and interference in the same channel of a terrestrial digital TV broadcast signal, eliminate the need for frequency conversion on the receiver side, and easily recognize the channel of the terrestrial digital TV broadcast being viewed. Become.

  Embodiments of the present invention will be described below with reference to the drawings.

[1] Description of a terrestrial digital broadcast TV receiver to which the present invention is applied

  Table 1 shows each reception channel and center frequency of terrestrial digital TV broadcasting.

  The reception channels of terrestrial digital TV broadcasting are UHF13ch to UHF62ch. The center frequency is 473 + 1/7 MHz for 13 ch, 479 + 1/7 MHz for 14 ch, and 767 + 1/7 MHz for 62 ch.

  Since the frequency band in which terrestrial digital TV broadcasting is introduced is in the range of UHF13 channel to 62 channels, it is necessary that the frequency can be received as the reception frequency range of the terrestrial digital broadcast TV receiver.

  Currently, broadcasting has started in December 2003 in the three major metropolitan areas (Kanto wide area, Chukyo wide area, and Kinki wide area). For example, broadcasting in the Kinki area is as shown in Table 2. ing.

  On the other hand, in the reception form of the current terrestrial analog TV broadcasting, including collective housing joint listening, joint reception accounts for almost half of all households. Most of the transmission bands in these hearing facilities are not widened to the UHF band, and UHF TV broadcasts are VHF_Low / High (VHF low / high band), VHF_MID (VHF midband) and VHF_SHB (VHF super band). In many cases, the data is down-converted to a low-frequency free channel (a channel that is not broadcast in the area) such as a high band.

  For this reason, joint reception is also assumed especially for a stationary TV receiver for terrestrial digital TV broadcasting. Therefore, the reception channel range of the receiver for terrestrial digital broadcasting is VHF_Low / High in addition to the UHF band. It is specified in the ARIB standard ARIB STD-B21 that it is desirable to support the band (VHF1ch to VHF12ch), the VHF_MID band (C13ch to C22ch) and the VHF_SHB band (C23ch to C63ch).

  Therefore, the stationary TV receiver for terrestrial digital TV broadcasting also receives the VHF_Low / High band (VHF1ch to VHF12ch), VHF_MID band (C13ch to C22ch) and VHF_SHB band (C23ch to C63ch) in addition to the UHF band. It is thought that it is often designed to be possible.

  Table 3 shows each reception channel and center frequency in the VHF_Low / High band (VHF1ch to VHF12ch).

  Table 4 shows each reception channel and center frequency of the VHF_MID band (C13ch to C22ch).

  Table 5 shows each reception channel and center frequency of the VHF__SHB band (C23ch to C63ch).

  In the present invention, in addition to the original UHF band 13ch to 62ch (470 MHz to 770 MHz), VHF_Low / High band (VHF1ch to VHF12ch), VHF_MID band (C13ch to C22ch) and VHF_SHB band (C23ch to C63ch) can also be received ( TV receivers for terrestrial digital TV broadcasting that can be selected and viewed) are targeted for application.

[2] Explanation of weak radio wave standards

  The weak radio wave standard will be described. The standard for weak radio waves is defined by the Ordinance of the Ministry of Internal Affairs and Communications as radio equipment that emits extremely weak radio waves, and is defined by the electric field strength at a point of 3 meters.

  FIG. 1 and Table 6 show the electric field strength (allowable value) for the frequency band defined by the weak radio wave standard.

  As shown in Table 6, the allowable value is limited to 500 μV / m for frequency bands of 322 MHz or less and 150 GHz or more. In addition, for the frequency band from 322 MHz to 10 GHz, the allowable value is limited to 35 μV / m in consideration of interference protection for land mobile service, UHF TV broadcasting, fixed service, and space service (earth station). For the frequency band from 10 GHz to 150 GHz, the allowable value is limited to 3.5 fμV / m (f is the used frequency band (GHz)) in consideration of the system noise temperature, the reception bandwidth, and the like.

  As long as the radio system according to the weak radio wave standard satisfies the electric field strengths shown in Table 6, there are no restrictions on the frequency, modulation method, and communication method, so a relatively free system design is possible.

[3] Explanation of wireless redistribution system for terrestrial digital TV broadcasting

  FIG. 2 shows an outline of a wireless redistribution system for terrestrial digital TV broadcasting.

  A terrestrial digital TV broadcast signal is received by the outdoor antenna 1 provided on the rooftop. The terrestrial digital TV broadcast signal received by the outdoor antenna 1 is guided to the TV terminal 3 provided on the wall surface of the room by the antenna cable 2.

  A transmitter 4 for redistribution is connected to the TV terminal 3. As a remote control transmitter, a redistribution remote control transmitter 10 is prepared in addition to a normal TV remote control transmitter 20. The redistribution remote control transmitter 10 is used to cause the transmitter 4 and the TV receiver 6 to input a desired channel of terrestrial digital TV broadcasting specified by the user by radio or infrared.

  Based on the desired channel of the terrestrial digital TV broadcast input by the redistribution remote control transmitter 10, the transmitter 4 determines the frequency of the terrestrial digital TV broadcast signal of the desired channel in a specific VHF band. The terrestrial digital TV broadcast signals obtained from the TV terminal 3 are collectively frequency-converted so as to be converted to the frequency of one vacant channel. And after extracting only the TV broadcast signal of the frequency of one specific empty channel of a predetermined VHF band from the terrestrial digital TV broadcast signal after the frequency conversion, it is below the allowable value of the weak radio wave standard. It retransmits wirelessly from the transmitting antenna 44 with weak radio waves.

  As one specific vacant channel in the predetermined VHF band, a channel of 322 MHz or less that is a vacant channel in the VHF band and loosely limits the weak radio wave standard is used. In this example, the C38 channel (center frequency: 315 + 1/7 MHz) of the VHF_SHB band is used as one specific empty channel of the predetermined VHF band. In this case, the allowable value of the weak radio wave standard is 500 μV / m.

  A redistribution receiver 5 is connected to a TV receiver 6 for terrestrial digital TV broadcasting. In addition to the original UHF band 13ch to 62ch (470 MHz to 770 MHz), the TV receiver 6 for terrestrial digital TV broadcasting includes a VHF_Low / High band (VHF1ch to VHF12ch), a VHF_MID band (C13ch to C22ch), and a VHF_SHB band ( (C23ch to C63ch) can also be received (selection viewing is possible).

  The receiver 5 receives the redistributed signal transmitted from the transmitter 4 by the receiving antenna 51, amplifies the received signal to a predetermined level that can be received by the TV tuner in the TV receiver 6, and then receives the TV receiver. Send to 6.

  The TV receiver 6 selects a specific vacant channel (C38 channel of the VHF_SHB band) in a predetermined VHF band, thereby terrestrial digital TV broadcasting designated by the transmitter remote control transmitter 10. Will be aired. Also, the TV receiver 6 displays the channel of the terrestrial digital TV broadcast that is currently viewed based on the desired channel of the terrestrial digital TV broadcast input by the redistribution remote control transmitter 10.

  FIG. 3 shows the configuration of the transmitter 4.

  The transmitter 4 includes a UHF receiver 41, a frequency converter 42, a VHF transmitter 43, a transmission antenna 44, a redistribution remote control receiver 45, and a controller 46.

  The terrestrial digital TV broadcast signal received by the outdoor antenna 1 is amplified by the UHF receiver 41 and then sent to the frequency converter 42. In the frequency converter 42, all the received terrestrial digital TV broadcast signals (received signals) and the local signals output from the frequency synthesizer 47 are mixed by the mixer 48. From the mixer 48, an addition signal and a subtraction signal of each received signal and the local signal are output. For example, assuming that the frequency of the received signal is fa and the frequency of the local signal is fb, an addition signal having a frequency of fa + fb and a subtraction signal having a frequency of fa−fb are output from the mixer 48. The output of the mixer 48 is sent to a BPF (band pass filter) 49, and only a signal of a specific empty channel in the predetermined VHF band (in this example, the C38 channel in the VHF_SHB band) is extracted.

  The frequency fb of the local signal output from the frequency synthesizer 47 is controlled by the control unit 46. The control unit 46 is a table indicating the desired channel of the terrestrial digital TV broadcast input from the redistribution remote control transmitter 10 via the redistribution remote control reception unit 45 and the relationship between the preset desired channel and the local frequency. Based on the above, the frequency fb of the local signal output from the frequency synthesizer 47 is controlled.

  In other words, the control unit 46 converts the frequency of the desired channel of the terrestrial digital TV broadcast into one specific empty channel in the VHF band (in this example, the C38 channel in the VHF_SHB band). The frequency fb of the local signal is controlled. Specifically, the frequency (fa−fb) of the subtraction signal between the terrestrial digital TV broadcast signal of the desired channel and the local signal is a specific one free channel (in this example, the VHF_SHB band) of the predetermined VHF band. The frequency fb of the local signal is controlled so as to be the frequency of (C38 channel).

  Table 7 shows a specific free channel (redistribution transmission center frequency) in a predetermined VHF band in the Kinki wide area where the channel on which terrestrial digital TV broadcasting is performed and the center frequency are shown in Table 2. ) Is set to the C38 channel (center frequency: 315 + 1/7 MHz) of the VHF_SHB band, the relationship between the desired channel of the terrestrial digital TV broadcast and the frequency of the local signal (redistribution local frequency) is shown.

  For example, when the desired channel is UHF13ch (center frequency: 473 + 1/7 MHz), the frequency fb of the local signal is set to 158 MHz. Since the frequency fa of the UHF 13ch TV broadcast signal is 473 + 1/7 MHz, the frequency of the subtraction signal between the UHF 13ch TV broadcast signal and the local signal is 315 + 1/7 (= 473 + 1 / 7-158) MHz, that is, in the VHF_SHB band. It becomes the frequency of C38 channel.

  That is, as shown in FIG. 4, assuming that all channels of the terrestrial digital TV broadcast signal received by the outdoor antenna 1 are A and the desired channel is B, the frequency of the desired channel B is 322 MHz by the frequency converter 42. The frequency is converted to the frequency of one specific empty channel C in the following predetermined VHF band.

  The terrestrial digital TV broadcast signal frequency-converted by the frequency converting unit 42 into one specific empty channel in the VHF band (in this example, the C38 channel in the VHF_SHB band) is amplified by the VHF transmitting unit 43 and transmitted to the transmitting antenna 44. Is transmitted wirelessly. Note that the VHF transmission unit 43 performs AGC so that the signal level transmitted wirelessly does not exceed the allowable value according to the weak radio wave standard.

  FIG. 5 shows the configuration of the receiver 5 and the TV receiver 6.

  The receiver 5 includes a receiving antenna 51 and a VHF receiving unit 52.

  The terrestrial digital TV broadcast signal wirelessly transmitted from the transmitter 4 (the terrestrial digital TV broadcast signal after being frequency-converted to one specific empty channel in the VHF band (in this example, the C38 channel in the VHF_SHB band)) And received by the receiving antenna 51. The TV broadcast signal received by the receiving antenna 51 is amplified by the VHF receiver 52 and then sent to the TV receiver 6 for terrestrial digital TV broadcast.

  The TV broadcast signal input to the TV receiver 6 is sent to the RF / IF unit 61. The user designates one specific empty channel of VHF_SHB predetermined by the TV remote control transmitter 20 (in this example, the C38 channel of the VHF_SHB band) as the channel selection channel. The channel selection channel (C38) designated by the TV remote control transmitter 20 is sent to the control unit 70 via the TV remote control receiver 73. The RF / IF unit 61 is controlled by the control unit 70 to select a channel selected by the TV remote control transmitter 20 (in this example, the C38 channel in the VHF_SHB band).

  The RF / IF unit 61 down-converts the C38 channel TV broadcast signal into a baseband signal. The signal obtained by the RF / IF unit 61 is digitally demodulated by the OFDM demodulator 62 and then sent to the AV decoder 63. The AV decoding unit 63 decodes the received signal and reproduces the video signal and the audio signal. The reproduced video signal is sent to the display unit (monitor) 64, and the reproduced audio signal is sent to the speaker 65. As a result, the terrestrial digital broadcast of the desired channel designated by the redistribution remote control transmitter 10 is broadcast.

  On the other hand, the desired channel of the terrestrial digital TV broadcast transmitted from the redistribution remote control transmitter 10 is input to the control unit 70 via the redistribution remote control receiver 72. The control unit 70 causes the OSD display unit 71 to generate an OSD video signal representing the desired channel based on the desired channel of the terrestrial digital TV broadcast input via the redistribution remote control receiving unit 72. The OSD video signal representing the desired channel generated from the OSD display unit 71 is sent to the display unit 64 via the AV decoding unit 63. As a result, the channel of the terrestrial digital TV broadcast currently being viewed is displayed on-screen on the display unit 64.

  For this reason, the user can recognize the channel of the terrestrial digital TV broadcast currently being viewed.

  In the above embodiment, the redistribution remote control receiver 72 is provided in the TV receiver 6 and the desired channel transmitted from the redistribution remote control transmitter 10 is received via the redistribution remote control receiver 72. The desired channel input from the redistribution remote control transmitter 10 to the transmitter 4 may be input from the transmitter 4 to the TV receiver 6 via the receiver 5. In this case, it is not necessary to provide the redistribution remote control receiver 72 in the TV receiver 6.

  In the above-described embodiment, a VHF_SHB band vacant channel and a channel of 322 MHz or less are set as one specific vacant channel in the VHF band. However, one vacant channel in the VHF_Low / High band or VHF_MID band is set. A channel that is 322 MHz or less may be set as one specific empty channel in the VHF band.

  In the above embodiment, since the frequency conversion is performed by the transmitter 4, it is possible to prevent the occurrence of the same channel interference of the terrestrial digital TV broadcast signal. Further, since the transmitter 4 converts the frequency of the terrestrial digital TV broadcast signal into the frequency of the VHF band that allows the TV receiver 6 to perform channel selection operation, the receiver 5 changes the frequency of the received signal to the original frequency. Since there is no need to return, there is an advantage that the circuit configuration of the receiver is simple and inexpensive. Further, since the receiver 5 only needs to receive and amplify a signal of a specific channel, there is an advantage that the circuit configuration of the receiver is simpler and less expensive. Furthermore, since the channel of the terrestrial digital TV broadcast currently being broadcast is displayed, the user can easily recognize the channel of the terrestrial digital TV broadcast currently being viewed.

It is a graph which shows the electric field strength (allowable value) with respect to the frequency band defined by the weak radio wave standard. It is a schematic diagram which shows the outline | summary of the radio | wireless redistribution system of terrestrial digital TV broadcasting. It is a block diagram which shows the structure of a transmitter. It is a schematic diagram for demonstrating the frequency conversion by the frequency conversion part of FIG. It is a block diagram which shows the structure of a receiver and TV receiver.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Outdoor antenna 4 Transmitter 5 Receiver 6 TV receiver 10 Redistribution remote control transmitter 41 UHF reception part 42 Frequency conversion part 43 VHF transmission part 45 Redistribution remote control reception part 46 Control part 70 Control part 71 OSD display part 72 Redistribution Remote control receiver

Claims (4)

In addition to the TV broadcast signal in the UHF band, which is the frequency band of the terrestrial digital TV broadcast signal, a TV receiver capable of receiving a TV broadcast signal in the VHF band and a terrestrial digital TV broadcast signal received by an outdoor antenna are input. Transmitter for wireless transmission after frequency conversion of input terrestrial digital TV broadcast signal, viewing desired channel input means for inputting desired viewing channel of terrestrial digital TV broadcast to transmitter and TV receiver, and transmission After receiving and amplifying the signal transmitted from the machine, it is equipped with a receiver for supplying to the TV receiver,
In the transmitter, the terrestrial digital TV broadcast signal of the desired viewing channel input by the desired viewing channel input means among the input terrestrial digital TV broadcast signals is a specific one free space in the preset VHF band. Frequency conversion means for collectively converting the input terrestrial digital TV broadcast signals so as to be converted to the channel frequency, and among the TV broadcast signals obtained by the frequency conversion means, the preset VHF band Filter means for extracting only TV broadcast signals in the frequency band of one specific empty channel, and transmission means for amplifying and wirelessly transmitting the TV broadcast signals extracted by the filter means,
The terrestrial digital TV broadcast wireless redistribution system characterized in that the TV receiver includes means for displaying a desired terrestrial digital TV broadcast viewing channel input by the desired viewing channel input means. The frequency of one specific empty channel in the VHF band set in advance is a frequency of one specific empty channel in the VHF band of 322 MHz or less. Wireless redistribution system. 3. The terrestrial digital TV according to claim 1, wherein the desired viewing channel input means is a remote control transmitter that transmits the desired viewing channel by radio or infrared to a transmitter and a TV receiver. Broadcast wireless redistribution system. The desired viewing channel input means includes: a remote control transmitter for transmitting a desired viewing channel by radio or infrared to a transmitter; a desired viewing channel transmitted from the remote control transmitter to the transmitter; the transmitter and the receiver; 3. The wireless redistribution system for terrestrial digital TV broadcasting according to claim 1, further comprising means for inputting to the TV receiver via

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