JP4466592B2 - Broadcast receiving apparatus, channel scanning method, and control program - Google Patents

Description

  The present invention relates to a broadcast receiver, a channel scan method, and a control program, and more particularly, to a digital broadcast broadcast receiver, a channel scan method, and a control program.

  Digital broadcasting has been started for terrestrial television broadcasting since 2003, and a transition from analog system is planned by 2011. This is called terrestrial digital broadcasting.

  In terrestrial broadcasting, licenses for broadcasting stations are granted by distributing the frequencies (hereinafter referred to as “physical channels”) so as not to overlap each other so as not to cause interference in each region. The area in this case is often a prefecture unit, but in a mountainous area, there may be a narrower area due to the installation of a relay station.

  A user who views terrestrial waves needs to set a channel when installing a television for the first time. By this operation, for example, it becomes possible to select a favorite broadcast station simply by pressing the number of the remote control device. This is an operation for associating a channel number (hereinafter referred to as “remote control number”) recognized by the user with a physical channel.

  This channel setting can be manually stored in the memory by the user if it is known in advance which broadcasting station is broadcasting on which physical channel in the area.

  However, since this operation is generally complicated, there is often a built-in function that automatically scans all the channels in the broadcast band one by one and automatically stores what is broadcast in the memory. This is called channel scanning.

  Next, an example of a conventional broadcast receiving apparatus will be described. FIG. 7 is a block diagram of an example of a conventional broadcast receiving apparatus. This figure shows the configuration of a terrestrial digital television receiver as an example.

  Referring to FIG. 1, an example of a conventional broadcast receiving apparatus includes an antenna 10, a front end unit 11, a back end unit 12, a display device (LCD: Liquid Crystal Display) 13, and a speaker 14. , A CPU (Central Processing Unit) 20 and a memory 21.

  The front end unit 11 includes a radio receiver 111, a local oscillator 112, and an OFDM (Orthogonal Frequency Division Multiplexing) demodulator 113.

  Although the display device 13 is composed of an LCD, the present invention is not limited to this, and can be composed of other display devices.

  The antenna 10 converts broadcast waves into high frequency signals. The front end unit 11 demodulates the high-frequency signal into a signal called TS (Transport Stream).

  The internal radio receiver 111 converts the high frequency signal into a signal suitable for demodulation such as an IQ signal or an IF (intermediate frequency) signal by using the local oscillation signal from the local oscillator 112. The local oscillator 112 oscillates and outputs a signal having a designated frequency.

  The OFDM demodulator 113 demodulates OFDM modulation such as IQ signal or IF signal, decodes scrambling processed by the broadcast wave of terrestrial digital television, interleaving, etc., takes out the original data of the modulation, It is converted into a standard signal called a TS signal.

  The back end unit 12 is a decoder that interprets the TS signal, demodulates and outputs the information-compressed video signal and audio signal included in the TS signal.

  The CPU 20 controls the entire terrestrial digital television receiver. In particular, the CPU 20 designates the oscillation frequency of the local oscillator 112, instructs the processing accompanying demodulation of the OFDM demodulator 113, and demodulates from the OFDM demodulator 113. BER (Bit Error Rate) of a received signal and C / N (Carrier to Noise ratio) information are extracted and used for channel selection.

  Next, the operation of this receiving apparatus will be described.

  A broadcast wave transmitted from the broadcast station is converted into a high frequency signal by the antenna 10 and input to the front end unit 11. Inside the front end unit 11, first, the local oscillator 112 starts oscillating at a frequency specified by the CPU 20. This frequency is considered to be a frequency having a certain relationship with the channel to be received.

  The high frequency signal converted by the antenna 10 is input to the radio receiver 111, and the local oscillation signal generated by the local oscillator 112 is also input to the radio receiver 111.

  The radio receiver 111 amplifies and mixes these two input signals, performs frequency conversion, converts the signals into IQ signals or IF signals, and outputs the signals to the OFDM demodulator 113.

  The OFDM demodulator 113 starts a demodulation operation in response to an instruction from the CPU 20, and demodulates the input IQ signal or IF signal by OFDM modulation. Further, after demodulation, decoding processing such as scrambling or interleaving of the OFDM carrier is performed, and desired modulation data is output in a format called TS.

  Since video data and audio data are superimposed on the TS signal after being compressed by a compression technique such as MPEG (Motion Picture Expert Group) 4 or AAC (Advanced Audio Coder), they are distributed by the back-end unit 12. Are decoded and decompressed, demodulated into original video data and audio data, and output to the display device 13 and the speaker 14. The display device 13 and the speaker 14 output the given video data and audio data.

  Next, the operation at the time of channel selection will be described. FIG. 8 is a configuration diagram of an example of the channel list. At the time of channel selection, information of the channel list 30 as shown in FIG. 8 is stored in the memory 21, and channel selection is performed according to this information.

  When the television function is activated, a remote control number somewhere in the list 30 (which may be the highest or the station received last time) is set as a default channel, and a physical channel corresponding to the remote control number is read from the memory 21. Then, a command is transmitted from the CPU 20 to the local oscillator 112 so as to receive the physical channel.

  At this time, the remote control number can be arbitrarily determined by the number corresponding to the broadcast recognized by the user, but in the case of terrestrial digital broadcasting, the remote control number is set in advance on the broadcast station side. For example, in the Kanto area, NHK General is 1, NHK Education is 2, Nippon Television is 4, Tokyo Broadcasting is 6, and so on.

  The physical channel is the number of the physical channel corresponding to the frequency at which the broadcast is actually transmitted. For example, in the Kanto region, NHK General is 27, NHK Education is 26, Nippon Television is 25, Tokyo Broadcasting Is 22,...

  When the user changes the channel, the command of the local oscillator 112 is sent again from the CPU 20 so as to receive the broadcast of the frequency of the physical channel corresponding to the remote control number designated by the user.

  Next, creation of the channel list 30 will be described. The channel list in FIG. 8 associates broadcast station names, broadcast wave physical channels, and their remote control numbers, but this is different for each region in the country. For example, it is different in the Kanto area and the Osaka area, and in other areas it is generally different for each prefecture. Therefore, the channel list needs to be updated when the receiver is used for the first time after manufacture and when the region is changed. In general, the information of the channel list 30 is stored in a non-volatile memory, retained even when the power is turned off, and can be rewritten as necessary.

  FIG. 9 is a flowchart showing an example of the operation of creating the conventional channel list 30. In terrestrial digital broadcasting, it is decided to use channels 13 to 62 in the UHF band of Japan, so an example of the operation of scanning from channel 13 to channel 62 is an example. It does not depend on the value of.

  Referring to FIG. 9, first, the CPU 20 sets a value of a variable (referred to as CH) for storing a channel to an initial value “13” (step 201). Next, an attempt is made to receive a broadcast wave on that channel (step 202). Specifically, the reception frequency is designated as the physical channel, and a demodulation start command is sent to the OFDM demodulator 113.

  Next, the CPU 20 determines whether or not a broadcast wave of terrestrial digital broadcasting is received in step 202 (step 203). Specifically, it is determined whether the OFDM demodulator 113 detects a broadcast wave. Whether or not a broadcast wave is detected can be determined based on whether BER is “0” or smaller than a prescribed value, or C / N is larger than a prescribed value. Alternatively, in the case of terrestrial digital broadcasting, attribute information related to a broadcast modulation method called TMCC (Transmission and Multiplexing Configuration Control) signal is multiplexed, and it can be determined whether the signal is demodulated. is there.

  If there is a broadcast wave (“Y” in step 203), the channel number of the broadcast wave and its broadcast station name are added to the channel list (step 204). At that time, the remote control number multiplexed in the broadcast wave is also decoded and added to the channel list. On the other hand, when there is no broadcast wave (in the case of “N” in step 203), the process proceeds to step 205.

  Next, following step 204, it is determined whether or not the variable (CH) for storing the channel is “62”, which is the end value (step 205). If it has reached “62” (in the case of “Y” in step 205), all the scans in the band have been completed, so this sequence is completed. On the other hand, if it has not yet reached “62” (in the case of “N” in step 205), “1” is added to the variable (CH) indicating the channel value (step 206), and the reception operation in step 202 is repeated. .

  Through the above operation, the channel list 30 is completed, and the user can easily select a channel.

  On the other hand, 9 broadcast channels are extracted from the received OFDM signal by a band pass filter, and further divided into 3 broadcast channels by another band pass filter, and then the presence or absence of broadcast waves is detected for each broadcast channel. The technique to do is disclosed (for example, refer patent document 1). This is similar to the present invention in that a plurality of channels are scanned without demodulating the broadcast wave.

  Further, in order to estimate the area where the user is present, an invention has been disclosed in which the area having the largest number of reception channels is estimated as the current area (for example, see Patent Document 2).

  Moreover, although the content is substantially the same as the invention described in Patent Document 2, an invention described as “utilizing C / N” is disclosed (for example, refer to Patent Document 3).

  Similarly to the present invention, an invention for shortening the scan time is disclosed (for example, see Patent Document 4). This is intended to increase the speed by taking out the broadcast channels including other regions based on NIT information included in the received signal and scanning with priority from the highest frequency of the used channels. .

  Further, similar to the present invention, another invention for the purpose of shortening the scan time is disclosed (for example, see Patent Document 5). This is an all-channel search, which estimates the area from the station installation information from the first station found and the own position information such as GPS, and scans only the stations in that area to increase the speed. It is.

Japanese Patent Laying-Open No. 2005-244481 (paragraphs 0036, 0045 to 0052 and FIG. 1) Japanese Patent Laying-Open No. 2004-312203 (paragraphs 0016 to 0017) JP 2004-312204 A JP 2000-253428 A JP 2003-273759 A

  However, the conventional broadcast receiving apparatus has a problem that it takes a long time for the entire channel scan because it takes time to synchronize the received wave in the process of performing OFDM demodulation.

  For example, if it takes 2 seconds to perform OFDM demodulation, it takes 100 seconds to complete scanning of 50 channels of 13 to 62 channels. During this time, the user cannot view the program.

  In the case of a television receiver installed in a home, the broadcast area changes only when moving normally, so even if the scanning time becomes long, it does not matter so much. However, for example, in an in-vehicle receiver or a portable terminal receiver in which a user moves regardless of an area, the time required for this scan is a factor that greatly impairs the merchantability.

  On the other hand, the invention described in Patent Document 1 is completely different from the present invention in that it scans every nine channels instead of scanning all channels at once.

  The invention described in Patent Document 2 is completely different from the present invention in that C / N information is always acquired during channel scanning. This is apparent not only from the description in the text of the specification but also from the table of FIG. 6 and steps 22 and 23 of FIG. In the present invention, in order to acquire C / N information, it is necessary to perform the synchronous operation of the OFDM demodulator, so that it takes a scan time equivalent to that of other conventional techniques. Therefore, in the present invention, although area estimation can be performed, the scan time cannot be shortened.

  Further, in the invention described in Patent Document 3, as in the invention described in Patent Document 2, it is necessary to perform the synchronization operation of the OFDM demodulator in order to acquire C / N information.

  In the present invention, the reception information is not used at first, whereas the invention described in Patent Document 4 is completely different from the present invention in that the reception information called NIT information is used first.

  Further, since the invention described in Patent Document 5 always uses BER in terms of configuration, the configuration is completely different from that in which reception information is not initially used as in the present invention.

  An object of the present invention is to provide a broadcast receiving apparatus, a channel scanning method, and a control program capable of increasing the scanning time as compared with the conventional technique.

In order to solve the above problems, a broadcast receiving apparatus according to the present invention is a broadcast receiving apparatus that sets a physical channel using channel scanning, and scans all of the preset physical channels to receive each channel. Radio receiving means for acquiring electric field strength, demodulating means for performing demodulation by selecting a certain number of physical channels in order of strong received electric field strength based on the received electric field strength obtained by the radio receiving means, and demodulation by the demodulating means Channel list that correlates the remote control number, physical channel, and broadcast station name with control means that determines the presence or absence of broadcast based on the result, estimates the reception area from the broadcast area, and sets the physical channel in the reception area And a first reception that records the result of scanning all physical channels and obtaining the received field strength of each channel. A second received field strength list in which, based on the received field strength, the physical channels are sorted in descending order of the received field strength, the signals of the physical channels are demodulated, and the determination result of the presence / absence of broadcasting is recorded; And a memory for storing an area-specific broadcast allocation list in which physical channels allocated for each area are recorded, and the control means is configured to maintain a high-order constant of channels determined to be broadcasted in the second received electric field strength list. If there is an area that is completely matched or much matched as a result of matching, several stations are compared with the broadcast allocation list for each area. Channel information is read from the regional broadcast allocation list and preset.

Also, the channel scan method according to the present invention is a channel scan method in a broadcast receiving apparatus that sets a physical channel using channel scan, and scans all of the preset physical channels and receives the received electric field of each channel. A radio reception step for acquiring strength, a demodulation step for performing demodulation by selecting a certain number of physical channels in descending order of reception field strength based on the reception field strength obtained in the radio reception step, and a demodulation result in the demodulation step whether the broadcast is determined on the basis of the estimates the receiving area from the area having the broadcast viewing including a control step for setting a physical channel in the receiving area, further wherein the broadcast receiver remote control ID, a physical channel and List of channels associated with broadcast station names and all physical channels A first received field strength list in which the results of obtaining the received field strength of each channel are recorded, and the physical channels are sorted in descending order of the received field strength based on the received field strength and the signals of the physical channels And a memory for storing a second received electric field strength list in which the determination result of presence / absence of broadcast is recorded and a broadcast allocation list by region in which physical channels allocated by region are stored, and the control step includes A certain number of higher-order channels of the channel determined to be broadcasted in the second received field strength list are collated with the broadcast allocation list classified by region, and as a result of the collation, there is an area where there is a complete match or many matches. If present, assign channel information of regions that completely match or match many to the channel list. Read from strike, characterized in that preset.

The control program according to the present invention is a control program for a channel scan method in a broadcast receiving apparatus that sets a physical channel using channel scan, and scans all of the physical channels set in advance in the computer, A radio reception step for obtaining a reception electric field strength of each channel; a demodulation step for performing demodulation by selecting a certain number of physical channels in descending order of the reception electric field strength based on the reception electric field strength obtained in the radio reception step; Determining whether or not there is a broadcast based on a demodulation result in the step, estimating a reception area from an area where the broadcast exists, and executing a control step of setting a physical channel in the reception area , and Broadcast receivers relate to remote control numbers, physical channels, and broadcast station names A list of digits, a first received field strength list that records the results of scanning all physical channels and obtaining the received field strength of each channel, and the physical fields in descending order of received field strength based on the received field strength. A second received electric field strength list in which channels are sorted and a signal of the physical channel is demodulated to record the presence / absence of broadcasting is recorded, and a regional broadcast allocation list in which physical channels allocated by region are recorded. And the control step performs collation between a certain upper station of the channel determined to be broadcast in the second received electric field strength list and the broadcast allocation list by region, and as a result of the collation, If there is an area that matches completely or matches many, the channel list will match exactly or most match. Reading channel information of location from the regional broadcast assignment list, characterized by preset.

  Next, the operation of the present invention will be described. The broadcast receiving apparatus according to the present invention has a portion for reading received signal strength (RSSI: Received Signal Strength Indicator) information by a CPU, and first uses that portion to perform RSSI of all bands without performing OFDM demodulation. Perform a value scan. Then, based on the scan result, OFDM demodulation is tried in the order of the strongest signal from the entire band, and it is determined whether it is terrestrial digital broadcasting. Finally, when the determination of several channels is completed, the area where the channel is likely to exist is confirmed by comparing it with a list stored in advance, and the channel of the broadcasting station existing in that area is determined. Preset as a receivable channel.

  According to the present invention, since the above-described configuration is included, it is possible to increase the scan time as compared with the conventional case.

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

  First, the first embodiment will be described. The first embodiment relates to a broadcast receiving apparatus and a channel scanning method. FIG. 1 is a block diagram of an example of a broadcast receiving apparatus according to the present invention.

  Referring to FIG. 1, an example of a broadcast receiving apparatus according to the present invention includes an antenna 1, a front end unit 2, a back end unit 3, a display device (LCD: Liquid Crystal Display) 4, a speaker. 5, a CPU (Central Processing Unit: control unit) 6, and a memory 7.

  The front end unit 2 includes a radio receiver 11, a local oscillator 12, and an OFDM (Orthogonal Frequency Division Multiplexing) demodulator 13.

  In addition, although the display apparatus 4 was comprised with LCD, it is not limited to this, It is also possible to comprise with another display apparatus.

  The antenna 1 converts a broadcast wave into a high frequency signal. The front end unit 2 demodulates the high-frequency signal into a signal called TS (Transport Stream).

  The internal radio receiver 11 converts the high frequency signal into a signal suitable for demodulation such as an IQ signal or an IF (intermediate frequency) signal using the local oscillation signal from the local oscillator 12. The local oscillator 12 oscillates and outputs a signal having a designated frequency.

  The OFDM demodulator 13 demodulates a signal such as an IQ signal or an IF signal by OFDM, decodes scrambling processed by the broadcast wave of terrestrial digital television, interleaving, etc., and extracts data of the modulation source , It is converted into a standard signal called TS signal.

  The back-end unit 3 is a decoder that interprets a TS signal, demodulates an information-compressed video signal and audio signal included therein, and outputs the demodulated signal.

  The CPU 20 controls the entire terrestrial digital television receiver. In particular, the CPU 20 designates the oscillation frequency of the local oscillator 12, instructs the processing accompanying the demodulation of the OFDM demodulator 13, and demodulates from the OFDM demodulator 13. BER (Bit Error Rate) of a received signal and C / N (Carrier to Noise ratio) information are extracted and used for channel selection. Also, RSSI information is read from the wireless receiver 11. Further, the CPU 20 executes processing at the time of channel scanning and channel selection, which will be described later.

The memory 7 includes a channel list 30 (see FIG. 8 described above) associated with a remote control number, a physical channel, and a broadcasting station name, and a first RSSI strength list 31 (see FIG. 2 described later) associated with an RSSI value for the physical channel. ), The first RSSI intensity list 31 is sorted (classified), and the second RSSI intensity list 32 (see FIG. 3 to be described later) to which information on the presence / absence of digital broadcasting is added, and broadcast waves by area (region). An area-specific broadcast assignment list 33 displaying a certain physical channel is stored. Further, as will be described later, the memory 7 also stores a control program for causing the CPU 6 to execute the channel scan method according to the present invention.

  Before describing the operation of the present invention, the channel list 30, the first RSSI strength list 31, the second RSSI strength list 32, and the regional broadcast assignment list 33 will be described.

  The channel list 30 is the same list as described with reference to FIG. As an example, the memory 7 stores a channel list 30 in the Kanto region as shown in FIG.

  FIG. 2 is a configuration diagram of an example of the first RSSI strength list 31 according to the present invention. Referring to the figure, the physical channel of the received signal and its RSSI strength are displayed. The leftmost number (“No”) indicates the order of received signals. That is, 50 channels are scanned in order from the physical channel 13 to the physical channel 62, and each RSSI intensity is obtained.

  FIG. 3 is a configuration diagram of an example of the second RSSI strength list 32 according to the present invention. Referring to the figure, the received physical channels are rearranged in the descending order of RSSI strength. The column “Presence / absence of terrestrial digital broadcasting” at the right end describes the result of examining the presence / absence of terrestrial digital broadcasting by demodulating the signals of these physical channels.

  FIG. 4 is a block diagram of an example of the regional broadcast allocation list 33 according to the present invention. Referring to the figure, a correspondence table of physical channels and remote control numbers is shown for each region.

  Next, the operation of the present invention will be described. Channel selection is performed according to the list of the channel list 30. That is, when the television function is activated, a channel of somewhere in the list (which may be the highest or the channel used last time) is defined as a specified channel, and the physical channel corresponding to the remote control number is read from the memory 7. Then, a frequency setting command is sent from the CPU 6 to the local oscillator 12 so as to receive the physical channel.

  At this time, the remote control number is the number corresponding to the broadcast recognized by the user. For example, in the Kanto area, NHK General is “1”, NHK Education is “2”, Nippon Television is “4”, Tokyo Broadcast is “6”,. This number is used in the television column of newspapers, and is sometimes simply referred to as a “channel number”.

  The physical channel is the channel number corresponding to the frequency at which the broadcast is actually transmitted. For example, in the Kanto area, NHK General is “27”, NHK Education is “26”, and Nippon Television is “25”. Tokyo Broadcasting will be “22”, etc. When the user changes the channel, the frequency setting command is retransmitted from the CPU 6 to the local oscillator 12 so as to receive the frequency of the physical channel corresponding to the remote control number designated by the user.

  Next, creation of the channel list 30 will be described. The channel list 30 in FIG. 8 associates broadcast station names, broadcast wave physical channels, and their remote control numbers, but this is different for each region in Japan. For example, it is different in the Kanto area and the Osaka area, and in other areas it is generally different for each prefecture. Therefore, when the receiver is used for the first time after manufacture and when the region is changed, it is necessary to change the list of FIG.

  5 and 6 are flowcharts showing an example of the operation for creating the channel list 30 in the present invention.

  In terrestrial digital television, since it is determined to use channels 13 to 62 in the UHF band in Japan, the operation of scanning between channels 13 to 62 will be described as an example. Does not depend on the channel value.

  First, the operation at the time of channel selection will be described. First, the CPU 6 sets the value of a variable (referred to as CH) for storing a channel to an initial value “13” (step 301). Next, the CPU 6 sets the front end unit 2 so as to receive the broadcast wave on that channel. Here, the OFDM demodulator 13 does not perform OFDM demodulation, and the radio receiver 11 has the RSSI which is the signal strength. (Step 302). This operation can generally be performed much faster than when performing OFDM demodulation.

  Next, the RSSI value acquired in step 302 is stored in the RSSI strength list 31 of FIG. 2 together with the selected physical channel (step 303).

  Next, it is determined whether or not the channel has reached the end value “62” (step 304). If it has not reached (“N” in step 304), “1” is set to the channel variable (CH). Add (step 305) and return to step 302. On the other hand, if it has reached, the process proceeds to step 306 to exit this loop.

  When step 306 is reached, the RSSI strength list 31 in FIG. 2 has been updated for all channels. Therefore, the CPU 6 sorts (sorts) this list 31 in descending order by RSSI value and writes it in the second RSSI strength list 32 (step 306).

  Next, among the physical channels written in the second RSSI strength list 32, the number M (M is a positive integer) of physical channels in which the RSSI value exceeds a predetermined value (threshold) is determined in the memory 7. An address is set (step 307).

  Next, an initial value “1” is set to the variable NO (step 308).

  Next, the channel in the order corresponding to the numerical value indicated by the variable NO is read from the second RSSI intensity list 32 and the reception operation is performed (step 309). The reception operation here is different from only reading the received electric field (RSSI) in step 302, and the process up to OFDM demodulation is performed. Therefore, this step takes extra time compared to step 302. As a result, it is determined whether or not a terrestrial digital broadcast wave has been detected by the OFDM demodulator 13, and the result is written in the "presence / absence of terrestrial digital broadcast" field of the second RSSI intensity list 32 (step 310).

  Next, it is determined whether or not the variable NO has reached M (step 311). If the variable NO has been reached (in the case of “Y” in step 311), the routine proceeds to step 314 to exit this loop. On the other hand, if not reached (in the case of “N” in step 311), the process proceeds to step 312.

  Since M is a numerical value obtained by selecting only a signal having a certain level of strength according to a predetermined threshold, if the variable NO reaches M, the remaining channel is estimated to be only noise and does not need to be received again. Because.

  Next, if the variable NO has not reached M (in the case of “N” in step 311), as an example, it is determined whether or not 5 stations have been found (step 312) and 5 stations have been found. If yes (“Y” in step 312), the process proceeds to step 314. On the other hand, if five stations are not found (in the case of “N” in step 312), “1” is added to the variable NO and the process returns to step 309. Although the end condition is “5 stations” here, the present invention is not limited to this, and the number of stations can be arbitrarily changed.

  Next, in step 314, the top five stations on the channel on which the terrestrial digital broadcast in the second RSSI intensity list 32 of FIG. 3 is present is compared with the regional broadcast allocation list 33 of FIG.

  Next, it is determined whether there is an area that matches in the collation (step 315).

  If there is an area that completely matches or many matches (“Y” in step 315), the channel list 30 assigns the channel information of the region that completely matches or most matches to each region. Read from the list 33 and preset (step 316).

  Next, only the physical channels that have not been scanned in 308 to 313 among the preset physical channels are scanned (step 317).

  If terrestrial digital broadcasting exists, the channel information is written in the channel list 30. If terrestrial digital broadcasting does not exist, the physical channel is deleted (deleted) (step 318), and the sequence ends.

  On the other hand, in step 315, if there is no area that completely matches or much matches (in the case of “N” in step 315), the estimation of the area has failed, so that FIG. As in the sequence (1), all physical channels are scanned (step 319), and the channel list is determined.

  In steps 306 and 314, processing such as sorting and matching is performed. Since these are algorithms well known to those skilled in the art, detailed description thereof is omitted.

  As described above, according to the first embodiment of the present invention, channel candidates to be received are determined without performing OFDM demodulation on all channels, so that channel scanning can be performed at high speed. .

  For example, if there are 13 to 62 physical channels to be received, the reception operation for reading only the RSSI value takes 100 ms, and the reception operation for performing OFDM demodulation takes 2 seconds, the conventional technique requires 50 × 2 ( Second) = 100 (seconds) is required.

  On the other hand, in the present invention, for example, in the Kanto area, it is expected that 9 stations in FIG. 8 can be received, so the time required for scanning is greatly reduced to 50 × 0.1 + 9 × 2 (seconds) = 23 (seconds). It becomes possible.

  Next, a second embodiment will be described. The second embodiment relates to a control program for the channel scan method. As described above, the memory 7 shown in FIG. 1 stores a control program for causing the CPU 6 to execute the channel scan method according to the present invention. The control program is a program for causing the CPU 6 to execute the procedure shown in the flowcharts in FIGS. 5 and 6.

  The CPU 6 reads the control program from the memory 7 and controls the radio receiver 11, the local oscillator 12, and the OFDM demodulator 13 based on the program. Since the contents of the control have already been described, description thereof is omitted here.

  As described above, according to the second embodiment of the present invention, a control program for determining channel candidates to be received can be obtained without performing OFDM demodulation on all channels.

It is a block diagram of an example of the broadcast receiver which concerns on this invention. It is a block diagram of an example of the 1st RSSI intensity | strength list | wrist 31 which concerns on this invention. It is a block diagram of an example of the 2nd RSSI intensity | strength list | wrist 32 which concerns on this invention. It is a block diagram of an example of the regional broadcast allocation list 33 according to the present invention. It is a flowchart which shows an example of the operation | movement which produces the channel list 30 in this invention. It is a flowchart which shows an example of the operation | movement which produces the channel list 30 in this invention. It is a block diagram of an example of the conventional broadcast receiving apparatus. It is a block diagram of an example of a channel list. It is a flowchart which shows an example of the operation | movement of creation of the conventional channel list 30. FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Antenna 2 Front end part 3 Back end part 4 Display apparatus 5 Speaker 6 CPU
7 Memory 30 Channel List 31 First RSSI Strength List 32 Second RSSI Strength List 33 Regional Broadcast Allocation List

Claims (6)

A broadcast receiving apparatus for setting a physical channel using channel scanning,
Wireless receiving means for scanning all of the preset physical channels and acquiring the received electric field strength of each channel;
Based on the received electric field strength obtained by the wireless receiving means, a demodulating means that selects and demodulates a certain number of physical channels in order of strong received electric field strength;
Control means for determining the presence or absence of broadcast based on the demodulation result in the demodulation means, estimating the reception area from the area where the broadcast exists, and setting the physical channel in the reception area ;
A list of channels in which remote control numbers, physical channels, and broadcast station names are associated; a first received field strength list that records the results of scanning all physical channels and obtaining received field strengths of each channel; and received field strengths Based on the second received electric field strength list in which the physical channels are sorted in descending order of the received electric field strength, the physical channel signals are demodulated, and the determination result of the presence / absence of broadcasting is recorded, A recorded area broadcast allocation list and a memory for storing,
The control means collates the upper-level fixed number of channels determined to be broadcasted in the second received electric field strength list with the broadcast allocation list classified by region, and as a result of the collation, there is a complete match or many When there is a matching area, the broadcast receiving apparatus is characterized in that channel information of a region that completely matches or mostly matches the channel list is read from the broadcast allocation list for each region and preset .   The broadcast receiving apparatus according to claim 1, wherein the broadcast receiving apparatus receives terrestrial digital broadcasting.   A channel scanning method in a broadcast receiving apparatus for setting a physical channel using channel scanning,
  A radio reception step of scanning all of the preset physical channels and acquiring the reception electric field strength of each channel;
  Based on the received electric field strength obtained in the wireless reception step, a demodulating step that selects and demodulates a certain number of physical channels in order of strong received electric field strength;
  Control step of determining presence / absence of broadcasting based on a demodulation result in the demodulation step, estimating a reception area from an area where the broadcast exists, and setting a physical channel in the reception area,
  Further, the broadcast receiving apparatus records a channel list in which a remote control number, a physical channel, and a broadcasting station name are associated with each other and scans all of the physical channels and records a result of acquiring a received electric field strength of each channel. A list, a second received field strength list in which the physical channels are sorted in descending order of the received field strength, the signals of the physical channels are demodulated, and the determination result of broadcasting is recorded, And a memory for storing a regional broadcast allocation list recording the allocated physical channels,
  In the control step, a certain number of higher-order channels of the channel determined to be broadcast in the second received electric field strength list are collated with the broadcast allocation list classified by region, and as a result of the collation, a complete match or many A channel scanning method characterized in that, when there is a matching area, channel information of a region that completely matches or matches a lot in the channel list is read from the regional broadcast allocation list and preset. 4. The channel scanning method according to claim 3, wherein digital terrestrial broadcasting is received.   A control program for a channel scan method in a broadcast receiving apparatus for setting a physical channel using channel scan,
  A wireless reception step of scanning all of the physical channels set in advance in the computer and acquiring the received electric field strength of each channel;
  Based on the received electric field strength obtained in the wireless reception step, a demodulating step that selects and demodulates a certain number of physical channels in order of strong received electric field strength;
  Determining the presence or absence of broadcast based on the demodulation result in the demodulation step, estimating the reception area from the area where the broadcast exists, and executing a control step of setting a physical channel in the reception area;
  Further, the broadcast receiving apparatus records a channel list in which a remote control number, a physical channel, and a broadcasting station name are associated with each other and scans all of the physical channels and records a result of acquiring a received electric field strength of each channel. A list, a second received field strength list in which the physical channels are sorted in descending order of the received field strength, the signals of the physical channels are demodulated, and the presence / absence of broadcast is recorded, And a memory for storing a regional broadcast allocation list recording the allocated physical channels,
  In the control step, a certain number of higher-order channels of the channel determined to be broadcast in the second received electric field strength list are collated with the broadcast allocation list classified by region. When there is a matching area, the channel program is read from the regional broadcast allocation list and presets the channel information of a region that completely matches or mostly matches the channel list. 6. The control program according to claim 5, wherein the control program receives terrestrial digital broadcasting.

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