JP2002158980A - Radio transmitter, radio receiver and radio transmitting/ receiving system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To transmit a plurality of signals or data through one system of transmission line. SOLUTION: At a transmission block, component video signals of a luminance signal Y and color difference signals Pb and Pr are subjected to FM modulation and filtered by a filter circuit in order to extract only required frequency components. The extract frequency components are added by an adder and collected to one system and an infrared LED is driven by a signal of that system to transmit an infrared signal. At a receiving block, signals received by a pin photodiode(PD) are amplified and filtered by means of filters corresponding to the luminance signal Y and the color difference signals Pb and Pr in order to extract only required frequency components. The extracted signals are inputted to an FM demodulator so that the component video signals of the luminance signal Y and color difference signals Pb and Pr are reproduced.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a radio transmission apparatus, radio reception apparatus, and radio transmission / reception system for high-speed signals such as high-definition video signals, and more particularly to an infrared wireless transmission technique.

[0002]

2. Description of the Related Art BS digital broadcasting was started in 2000, and video sources have been diversified by providing high-definition image quality and various contents by digital high-definition and interactive services. On the other hand, flat display panels such as plasma display panels (hereinafter, referred to as PDPs) and liquid crystal panels have become widespread as image display devices, and lifestyles such as home theaters using large screen wall-mounted televisions have been greatly changed.

As described above, the installation and portability of the monitor section itself are improved by making the image display device itself thinner and lighter, while the connection to a video signal source such as a tuner or a video deck still requires cable wiring. However, the merits of installation and portability are not fully utilized. Even a wall-mounted TV, which is important as an interior, may even lose its merit. Further, regarding the problem of cable connection, the same has been pointed out in presentations and the like in which a liquid crystal projector and a personal computer are combined, and wireless transmission of video transmission is desired.

[0004] A wireless video and audio transmission system includes:
Japan Electronic Machinery Manufacturers Association Standard (CP-1206: Infrared spatial analog audio transmission system, CP-1207:
Each company has released a product conforming to the infrared spatial analog video transmission system), but it can transmit the current NT
High-definition video such as digital high-definition video, which is at the SC system level, has been postponed for future study.

[0005]

SUMMARY OF THE INVENTION To solve the above problems, 19
Proceedings of 1997 Annual Conference of the Institute of Image Information and Television Engineers: Development of an RGB signal space transmission device using infrared rays (pp321-32)
2) discloses an infrared wireless transmission technology of a personal computer VGA signal, and shows a wireless transmission means of a high definition video signal. In the above-mentioned known example, the RGB baseband signal is converted into a luminance signal (Y) and color difference signals (RY, BY), and the baseband band of the luminance signal is set to 12 MHz and the baseband band of the color difference signal is set to 2 MHz. FM modulation with band limitation, luminance signal Y signal, RY signal, BY
Signals are transmitted using a total of three lines using infrared LEDs and pin photodiodes (hereinafter referred to as PDs). Further, in the above-mentioned known example, three sets of optical lens systems are used corresponding to the infrared LEDs and PDs for three lines, and the set size is large. In addition, it is difficult to align the optical axis between transmission and reception with three lens systems, and there is a possibility that an optical axis shift may occur. In addition, there is a possibility that the transmission distance of the product varies due to assembly variations at the time of mass production. In order to incorporate it into a wall-mounted television or the like, it is necessary to make the set shape compact, and further, it is required that the user can easily adjust the installation. Therefore, more practical means is desired.

An object of the present invention is to provide a radio transmission receiving technique capable of transmitting a plurality of signals or data through a single transmission line.

[0007]

SUMMARY OF THE INVENTION The present invention has been made to achieve the above-mentioned object. In a transmitting section, a component video signal of a luminance signal Y and color difference signals Pb and Pr is FM-modulated, and the modulated signal is modulated. Only necessary frequency components are extracted by filtering with a filter circuit, and the extracted frequency components are added by an adder to be combined into one system, and the infrared LED is driven by the one system signal and transmitted as an infrared signal.
On the other hand, in the receiving section, the signal received by the PD is amplified, filtered by filters corresponding to the luminance signal Y and the color difference signals Pb and Pr, and only the necessary frequency components are extracted. The extracted signal is input to the FM demodulator. The component video signals of the luminance signal Y and the color difference signals Pb and Pr are reproduced. By combining the signals of the three systems into one system by frequency multiplexing with an adder, only one system is required for the transmission / reception system consisting of the LED and PD, so that the optical lens system is also one system and is superior to the case of three systems in cost and shape. And a practical set can be realized.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The embodiments of the present invention will be described below with reference to the drawings by using some embodiments. FIG. 1 is a block diagram showing a first embodiment of a wireless transmission / reception system according to the present invention. FIG. 1A shows a transmission block, and FIG. 1B shows a reception block. In the figure, the wireless transmission / reception system includes a transmission block 1 and a reception block 20.
0. Transmission block 1 in FIG.
, 2 to 4 are FM modulation circuits, 5 is a high-pass filter (hereinafter referred to as HPF), 6 and 7 are band-pass filters (hereinafter referred to as BPF), 8 is an addition circuit, and 9 is an amplification circuit (hereinafter referred to as an amplification circuit). , AMP), 10 is a DC bias circuit, 11 is an infrared light emitting diode (hereinafter, referred to as infrared LED), and 20 to 22 are terminals. In the receiving block 200 of FIG. 1B, 12 is a pin photodiode (hereinafter, referred to as PD), 13 is AMP, and 14 is HP.
H, 15, 16 are BPF, 17 to 19 are FM demodulation circuits,
23 to 25 are terminals.

In FIG. 1, if the luminance signal of the component video signal is Y and the color difference signals are Pb and Pr, the luminance signal Y applied to the terminals 20 to 22 and the color difference signal Pb,
Pr is FM-modulated by FM modulation circuits 2 to 4, respectively.
The FM-modulated luminance signal Y passes through the HPF 5, and the color difference signals Pb and Pr pass through the BPFs 6 and 7, respectively. Only necessary frequency components are extracted and added by the adder 8 to be frequency-multiplexed. Note that the frequency components extracted by the HPF 5, the BPFs 6, 7 are arranged so as not to overlap with each other. The output of the adder circuit 8 drives the infrared LED 11 via the AMP 9 and the DC bias circuit 10, and is frequency-modulated, and the frequency-multiplexed luminance signal Y and the color difference signals Pb and Pr are luminance-modulated by the infrared LED. It is radiated into space as an FM modulated signal. Any number of infrared LEDs 11 may be used, but as the number increases, the transmission power increases and the transmission distance can be increased.

On the other hand, in the receiving block 200, a signal received by the PD 12 which is a light receiving element and converted into an electric signal is converted into an AM signal.
The signal is amplified at P13, the luminance signal Y passes through the HPF 14, and the color difference signals Pb and Pr pass through the BPFs 15 and 16, respectively.
Necessary frequency components are extracted, demodulated by FM demodulation circuits 17 to 19, reproduced as a luminance signal Y and color difference signals Pb and Pr, and output from terminals 23, 24 and 25 to a display device, a television receiver or a personal computer, respectively. I do. The signals received by the PD 12 are the FM of the luminance signal Y and the color difference signals Pb and Pr.
This is a signal in which a modulated signal or the like is multiplexed. In demodulation, a signal other than a desired frequency becomes noise.
It is removed by BPFs 15 and 16.

FIG. 2 is a block diagram showing an embodiment of an FM modulation circuit used in the present invention.
For example, as shown in FIG.
CO) can be easily realized. The terminal 27 receives the luminance signal Y, the color difference signal Pb or the color difference signal Pr,
Modulation is performed at O26, and a modulation signal is obtained at the terminal 28.

FIG. 3 is a circuit diagram showing an embodiment of an FM demodulation circuit used in the present invention. As shown in FIG. 3, the FM demodulation circuits 17 to 19 are composed of an AMP 29, a comparator 30, a delay circuit 31, an exclusive logic It can be composed of the sum circuit 32 and the LPF 33.

FIG. 4 is a waveform diagram of a main part of the FM demodulation circuit shown in FIG. 3. FIG. 4 (a) shows a signal supplied to the terminal 27 in FIG. 2, and FIG. 4 (b) shows a signal supplied to the terminal 27 in FIG. 28, terminal 3 in FIG.
5 is an FM-modulated signal to be supplied to the signal No. 5. The FM modulation signal supplied to the terminal 35 is amplified by the AMP 29 and compared with the reference voltage source 34 by the comparator 30 to obtain the signal shown in FIG.
As shown in FIG. The digitized signal contains frequency change information. The delay circuit 31 can obtain the signal shown in FIG. 4D by delaying the output of the comparator for a predetermined time. The larger the delay amount in the delay circuit 31, the better, but it is necessary to make the wavelength shorter than half the wavelength of the maximum frequency. The exclusive-OR circuit 32 performs an exclusive-OR operation of the signal by delaying the output of the comparator 30 and the output of the comparator 30.
As shown in the xOR output, the pulse density changes according to the frequency change. The ExOR output is passed through the LPF 33 to smooth it and reproduce the original signal. FM modulation, F
There are various other techniques for M demodulation, and these are known. It should be added that any FM modulation or demodulation method may be used.

In the present invention, the luminance signal Y, the color difference signal Pb,
After the respective Prs are FM-modulated, only the necessary frequency components are extracted by a filter, added by the adder circuit 8 and frequency-multiplexed. The most characteristic feature is that the infrared LED 11 can be driven by one system. The transmission system can be extremely simple. As described above, in the known example, the infrared LED and the corresponding PD are composed of the luminance signal Y and the color difference signals Pb and Pr.
And the system is divided into three systems, and the spatial transmission system is enlarged. According to the present invention, the frequency multiplexing can be simplified to one system.

The arrangement of the components of the luminance signal Y and the color difference signals Pb and Pr during frequency multiplexing will be described below with reference to FIGS. FIG. 5 is a characteristic diagram showing a first example of the frequency characteristics of the luminance signal and the color difference signal, and FIG. 6 is a characteristic diagram showing a second example of the frequency characteristics of the luminance signal and the color difference signal. FIG. 8 is a characteristic diagram showing a third example of the frequency characteristic of the luminance signal and the color difference signal, and FIG. 8 is a characteristic diagram showing a fourth example of the frequency characteristic of the luminance signal and the color difference signal. FIG. 5 shows a method of limiting the band of the color difference signals Pb and Pr among the luminance signal Y and the color difference signals Pb and Pr so as to widen the luminance signal Y band.
r, Pb, and the luminance signal Y. Color difference signals Pb, Pr
Is filtered by the BPF, but it is not necessary to limit the upper limit frequency since the luminance signal Y does not need to consider the influence on the others, and the HPF may be used.

In FIG. 6, the arrangement of the luminance signal Y and the color difference signals Pb and Pr is opposite to that of the frequency characteristic shown in FIG. In the case of an infrared LED or the like whose frequency characteristics cannot be obtained so widely, transmitting the luminance signal Y signal in a low frequency region may be advantageous in terms of image quality. In general, the sensitivity of the human eye to the luminance signal Y is higher in the video signal than in the color difference signals Pb and Pr. Conversely, since the color difference signal has lower sensitivity than the luminance signal,
The band may be limited, and most of the current video systems increase the transmission efficiency by limiting the band of the color component. In FIG. 6, the filter for the luminance signal Y signal is B
Since it is necessary to be a PF, each of the HPFs 5, 5 and 14 in FIG. 1 must be changed to a BPF.

FIGS. 7 and 8 show a luminance signal Y and color difference signals Pb and P, respectively.
r also shows the frequency arrangement in the case where transmission is performed in the baseband without band limitation. In the case of a high-definition television, the baseband signals of the luminance signal Y and the color difference signals Pb and Pr are 30 MHz, and if this is FM-modulated, a bandwidth of 60 MHz is sufficient, so the bandwidth should be determined as shown in FIGS. Thus, the luminance signal Y and the color difference signals Pb and Pr can be transmitted without limiting the bandwidth. In the case of the muse television, since the bandwidth of the luminance signal Y is 20 MHz and the bandwidth of the color difference signals Pb and Pr is 7 MHz, if the bandwidth is doubled, the transmission can be performed without limiting the bandwidth.

In the characteristic diagrams shown in FIGS. 7 and 8, since the bands of the luminance signal Y and the color difference signals Pb and Pr are not limited, the deterioration of the image quality is naturally reduced. When a device having a wide frequency band such as a high-frequency radio wave, a laser, or a high-speed LED can be used, transmission should be performed without band limitation, and the arrangement shown in FIGS. In particular, FIG. 8 shows an example in which there is a sufficient transmission band and the arrangement of the luminance signal Y and the color difference signals Pb and Pr can be arranged at regular intervals. It goes without saying that the transmission path may be a coaxial cable, an optical fiber, a plastic fiber, or the like, depending on the light emitting and receiving devices as well as the space. As described above, according to the present invention, the luminance signal Y and the color difference signals Pb, Pr3
Can be transmitted as a single line, so that the spatial transmission system has a simple configuration, and a practical transmission / reception system can be realized.

Hereinafter, a second embodiment of the wireless transmission / reception system according to the present invention will be described with reference to FIG. FIG. 9 is a block diagram showing a second embodiment of the wireless transmission / reception system according to the present invention. FIG. 9 (a) shows a transmission unit, and FIG. 9 (b) shows a reception unit. The feature of the second embodiment is that video signals RGB signals can be transmitted as video signals instead of the luminance signal Y and the color difference signals Pb and Pr, and wireless transmission of a PC signal source and the like is possible. Although the RGB signal can be transmitted in the above-described known example, the vertical synchronization signal (hereinafter, referred to as Vsync) is complicated in circuit such as frequency multiplexing using a special on / off keying method. . In this embodiment, the same circuit system as the luminance signal Y and the color difference signals Pb and Pr can be used as it is by combining a horizontal synchronization signal (hereinafter, referred to as Hsync) and Vsync into one system and multiplexing them into a video signal. I did it. A composite synchronizing signal (hereinafter, C
This is called sync. ) Is generally used for computer signals, and is often referred to as Sync on G because it is often superimposed on a G video signal. The present embodiment is characterized in that a Csync superimposing circuit is incorporated in a transmission circuit system and a synchronization separation circuit is incorporated in a reception circuit system to realize an apparently RGBHV interface, thereby achieving user convenience and simplification of the circuit. In FIG. 9, the transmission block 101
40 is a synchronizing signal superimposing circuit, 41 of the receiving block 102
1 is a synchronization separation circuit, and the others are the same circuit blocks as in FIG. 1. The same circuit blocks are given the same reference numerals and description thereof is omitted.

The synchronizing signal superimposing circuit 40 can be realized, for example, by the configuration shown in FIG. FIG. 10 is a circuit diagram showing one embodiment of the synchronizing signal superimposing circuit used in the present invention.
4 is an inverting circuit, 45 is an exclusive OR circuit, 42 is a video signal clamp circuit, and 43 is a switching circuit. An inverted signal of Hsync and Vsync is operated by an exclusive OR circuit 45 to generate a composite synchronization signal Csync.

FIG. 11 is a waveform diagram of a main part of the synchronization signal superimposing circuit shown in FIG. 10, FIG. 11 (a) is a waveform diagram of a video signal G input to the clamp circuit, and FIG. 11 (b) is an exclusive logic. FIG. 11 is a waveform diagram of the horizontal synchronizing signal input to the sum circuit 42,
(C) is a waveform diagram of the vertical synchronization signal input to the inverting circuit,
FIG. 11D is a waveform diagram of a decoded synchronizing signal output from the exclusive OR circuit, and FIG. 11E is a waveform diagram of a signal in which a synchronizing signal is superimposed on the video signal G output from the switching circuit. .

In this embodiment, a synchronizing signal is superimposed on G as a video signal. The video signal G is clamped by the clamp circuit 42, the DC level is fixed, and input to the switching circuit 43. A voltage source 46 is connected to the other terminal of the switching circuit 43, and the clamped video signal G and the voltage of the voltage source 46 are switched by the switching circuit 43 and output. That is, the switching circuit 43 is switched to the power supply side in the synchronization signal portion, and the power supply voltage is output, and this is superimposed on the video signal G as a synchronization signal. Therefore, the switching of the switching circuit 43 is performed by the Csy of the output of the exclusive OR circuit 45.
nc, and as a result, a video signal waveform on which Csync is superimposed can be obtained.

The signal generated in this way is referred to as FM in FIG.
When input to the modulation circuit 3, the decoded synchronization signal is transmitted together with the video signal G. Since the operation of the transmission circuit is the same as that of the first embodiment, detailed description is omitted. The receiving block 102 is the same as the first embodiment up to the output of the FM demodulation circuit 18, and the subsequent steps will be described. The video signal G output from the FM demodulation circuit 18 has a video signal waveform on which Csync is superimposed in accordance with the transmission signal, and it is necessary to separate and extract the synchronization signal.

The synchronization separation circuit can be realized, for example, by the configuration shown in FIG. FIG. 12 is a circuit diagram showing an embodiment of the sync separation circuit used in the present invention. 13 is a waveform diagram of a main part of the synchronization signal separation circuit shown in FIG. 12, FIG. 13A is a waveform diagram of a video signal G on which a synchronization signal input to the clamp circuit is superimposed, and FIG. 13 (c) is an output waveform diagram of the LPF, and FIG. 13 (d) is an output waveform diagram of the first comparator.
7 is an output waveform diagram of the next stage comparator. In FIG. 12, 46 is a clamp circuit, 47 is a comparator, 48
Is an LPF and 49 is a comparator. The video signal on which FM demodulation and Csync are superimposed as shown in FIG. 13A is clamped by the clamp circuit 46 and the DC level is fixed. The video signal whose DC level is fixed and the voltage of the voltage source 50 are compared by the comparator 49. By selecting the voltage level of the voltage source 50 to be smaller than the black level of the video signal and larger than the synchronization signal head level, the output of the comparator 47 becomes Csync as shown in FIG. When the extracted Csync is input to the LPF 48, FIG.
The waveform of the output of the LPF 48 shown in FIG. When this waveform is input to the comparator 49 and compared with the voltage level of the voltage source 51, the output becomes a vertical synchronization signal as shown in FIG. The voltage level of the voltage source 51 is indicated by a dotted line in the output waveform of the LPF 48 in FIG. The time constant of the LPF 48 may be selected to be larger than the width (narrow pulse width) of the horizontal synchronization signal and smaller than the width (thick pulse width) of the vertical synchronization signal in FIG. Although Csync is still superimposed on the video signal, there is no problem if the video signal is output as it is. Generally, a monitor for displaying an image is provided with a pedestal clamp circuit for the image signal, and is controlled so that the black level of the image signal becomes a specified level. It is a well-known fact that there is no problem even if Csync is input as it is as a horizontal synchronization signal. As described above, according to this embodiment, a video signal of a PC or the like having an RGB interface can be frequency-multiplexed and wirelessly transmitted to one system, and a more convenient system can be provided.

FIG. 14 is a block diagram showing a third embodiment of the wireless transmission / reception system according to the present invention.
Shows a transmitting unit, and FIG. 14B shows a receiving unit. In the figure, 60 is a video and audio signal source, 61 is a transmission unit, 62 is a reception unit, 63 is a video and audio monitor, 64 is a microcomputer, 201 is a transmission module,
202 is a receiving module, and 69 is a microcomputer. The feature of this embodiment is that the transmitting unit 61
In addition to transmitting wirelessly video and audio signals, the transmission unit 61 and the reception unit 62 can communicate with each other by exchanging status signals bidirectionally, so that mutual status can be confirmed.

A BS digital tuner used in BS digital broadcasting held since 2000 determines the format of a received signal and outputs the result as data for format setting. The video and audio signal source 60 corresponds to the BS digital tuner, and outputs a video signal, an audio signal, and a format setting data signal. When making these signals wireless, care must be taken in handling the format setting data signals. That is, the video and audio monitor 63 determines the input video format based on the data, and optimally processes the number of scanning lines and resolution of the displayed video.

If the format setting data is transmitted for a predetermined time when the signal source is switched, or for copy protection, the approved video and audio monitor 63 or the standard is used. When transmitting the video signal and the audio signal only to the video and audio monitor 63, the two-way communication is required. That is, if the format setting data signal is a one-way communication as well as the video signal and the audio signal, the video / audio monitor 63 is used for the video / audio signal 63 in an instantaneous interruption caused by a person crossing the transmission path. In addition, the format setting data signal is not input, and the display mode setting may become unclear, and the operation of the video and audio monitor 63 may fall into abnormal response. In addition, just crossing the front of the vehicle greatly changes the operation state, and puts a burden on the user, for example, causing extra concern. If the video or audio is interrupted for a moment, you shouldn't worry too much.

In order to perform copy protection,
Therefore, the video signal and the audio signal are transmitted only when a signal indicating that the monitor or the receiver or the receiver conforms to the standard is returned. For this purpose, an identification signal for copy protection is transmitted to the video and audio monitor 63, and the video and audio signals are transmitted to the video and audio monitor 63 only when a predetermined signal is returned from the video and audio monitor 63. To do it. In this case, if the transmission path is cut off between the transmission unit 61 and the reception unit 62, transmission of the video signal and the audio signal becomes impossible.

In order to address the above problem, the present invention allows only status signals to be communicated in both directions so that status can be monitored by each other. In other words, this is realized by communicating between the transmitting unit 61 and the receiving unit 62 at regular intervals according to an inquiry and response procedure. If transmission is not possible due to any obstacle such as an obstacle on the transmission path, a response will not be returned even if an inquiry is made. If there is no response after waiting for a certain time, it can be determined that the line is disconnected. Further, the microcomputer 64 measures the time of the line disconnection, determines whether the disconnection is an instantaneous disconnection or a fundamental system abnormality, and transmits format setting data to the video and audio monitor 63.

The transmitting module 201 shown in FIG. 14 may be configured, for example, as shown in FIG. 15 and 16 show FIG.
15 is a block diagram showing an embodiment of a transmission / reception module used in the wireless transmission / reception system shown in FIG. 15, FIG. 15 shows a transmission module, and FIG. 16 shows a reception module. FIG.
, 72 and 73 are FM modulation circuits, 74 is an FSK modulation circuit, 75 to 77 are BPFs, 112 is a PD, 113 is an AMP, 77 is a BPF, 79 is an ASK demodulation circuit,
The other parts are the same as those in FIG. 1, and the same blocks are assigned the same numbers, and the image-based FM modulation circuits 2 to 4 and the HPF 5,
The description of the operation of the BPFs 6 and 7 is omitted.

The L channel signal and the R channel signal of the stereo sound are FM-modulated by FM modulation circuits 72 and 73, respectively, and only necessary frequency components are extracted by BPFs 75 and 76 and input to an addition circuit 108. The data transmission signal TxT is subjected to binary FM modulation, that is, FSK modulation, by the FSK modulation circuit 74, and only necessary frequency components are extracted by the BPF 77 and input to the addition circuit 108. In the adder circuit 108, the luminance signal Y of the video signal, the color difference signals Pb and Pr, the stereo sound L
The channel signal, the R channel signal, and the data TxT are frequency-multiplexed and unified. Although not specifically shown here, the frequency regions of the luminance signal Y of the video signal, the color difference signals Pb and Pr, the stereo audio L channel signal and the R channel signal, and the data TxT are arranged so as not to overlap each other. The output of the adder circuit 108 is AMP9, DC
The infrared LED 11 is driven via the bias circuit 10, and the frequency-multiplexed information is emitted to space.

On the other hand, the receiving module 202 shown in FIG. 14 may be constituted by, for example, the blocks shown in FIG. FIG. 16 is a block diagram showing one embodiment of a receiving module used in the wireless transmitting / receiving system according to the present invention. In FIG. 16, 79 to 81 are BPFs, 82 and 83 are FM demodulation circuits,
84 is an FSK demodulation circuit, 85 is an ASK modulation circuit, 111
Is an infrared LED, and the others are the same blocks as in FIG.
Demodulation circuits 17 to 19, HPF 14, BPF 15, 1
The detailed description of the operation 6 is omitted.

The L-channel signal and the R-channel signal of the stereo sound are BPFs 79 and 80, respectively, to extract only necessary frequency components, and are FM-demodulated by FM demodulation circuits 82 and 83 to reproduce the original signals. The data signal TxT is BPF81
, Only the necessary frequency components are extracted and FSK demodulated by the FSK demodulation circuit 84 to reproduce the original binary signal, that is, the data signal. Here, the output of the FSK demodulation circuit 84 is called RxR for convenience in the sense of the received data. The original signal is TxT in FIG.

By the way, since the transmitting unit 61 and the receiving unit 62 communicate with each other, data returned from the receiving unit 62 to the transmitting unit 61 is required. This return data is transmitted to the ASK modulation circuit 85 and the infrared LED 111 of the receiving module 202 of FIG. 16 and the PD1 of FIG.
12, AMP113, BPF78, ASK demodulation circuit 79
The transmission is realized by the configuration of

The ASK modulation circuit 85 can be configured, for example, as shown in FIG. FIG. 17 is a circuit diagram showing one embodiment of the ASK modulation circuit used in the present invention. In FIG. 17, reference numeral 86 denotes a transmission circuit, and 87 denotes a gate circuit.

FIG. 18 is a waveform diagram of a main part of the ASK modulation circuit shown in FIG. 17, FIG. 18 (a) is a waveform diagram of data input to the gate circuit, and FIG. 18 (b) is an output waveform diagram of the transmission circuit. FIG. 18C is an output waveform diagram of the gate circuit. As shown in the waveform diagram of FIG. 18, this is a modulation method in which a carrier exists only in the data “H” period, and a simple configuration is sufficient. According to the data shown in FIG. 18A, the output of the transmitting circuit 86 shown in FIG. 18B is gated by the gate circuit 87, and as shown in FIG. Can be

The ASK demodulation circuit 79 is, for example, shown in FIG.
It can be configured as follows. FIG. 19 is a circuit diagram showing an embodiment of an ASK demodulation circuit used in the present invention. 20 is a main part waveform diagram of the ASK demodulation circuit shown in FIG. 19, FIG. 20 (a) is an output waveform diagram of a buffer, and FIG.
20B is a waveform diagram of the terminal voltage of the resistor, and FIG. 20C is an output waveform diagram of the comparator.

In FIG. 19, 88 is a buffer, 89 is a diode, 90 is a resistor, 91 is a capacitor, 92 is an AMP,
93 is a comparator. The signal received by the PD 112 and converted into an electric signal is amplified by the AMP 113 and
Only necessary frequency components are extracted by the PF 78 and input to the ASK demodulation circuit 79. In the ASK demodulation circuit 79, FIG.
(A) shows the output data of the buffer 88. This data (T × R) is half-wave rectified by the diode 89 and the waveform at both ends of the resistor 91 is obtained by the parallel circuit of the resistor 90 and the capacitor 91.
As shown in FIG. 20 (b), it becomes equivalent to the original binary signal.
The signal is amplified by the MP 92, shaped by the comparator 93, and output as a binary signal shown in FIG.

The ASK modulation method has been described as a method of transmitting return data from the receiving unit 62 to the transmitting unit 61 because the circuit configuration can be relatively easily realized, and other methods may of course be used.

As described above, the bidirectional communication of the state becomes possible, and the data input from the terminal 66 is transferred to the microcomputer 16.
The information including the negotiation is transmitted from the transmission module 201, received and demodulated by the reception module 202, and input to the microcomputer 69 as RxR data. The microcomputer 69 sends back information including negotiation from the receiving module 202 to the transmitting module 201 using the ASK modulation circuit 85 or the like in FIG. Microcomputer 64
Processes the returned information and checks whether it is in a normal communication state with the receiving unit 62 or whether the video and audio monitor 63 matches the copy protection. As a result of this check, if the receiving unit 62 is in a normal communication state or the monitor 63 is approved, the microcomputer 69 outputs the same data as the data at the terminal 66 of the transmitting unit 61 to the terminal 70. In this way, the transmission unit 61 and the reception unit 62 operate while negotiating, so that a stable wireless video transmission can be performed even with a video interface compatible with format setting data or with copy protection, and a user-friendly system is provided. Can be provided.

Even if the format setting data is supported, if the format setting data is always transmitted from the transmission unit 61 to the reception unit 62, there is no problem due to the interruption of the transmission path. And the microcomputer 64 can be omitted.

FIG. 21 is a block diagram showing a fourth embodiment of the wireless transmission / reception system according to the present invention.
Shows a transmitting unit, and FIG. 12B shows a receiving unit. In the wireless transmission / reception system of FIG.
The transmission power control can be performed by applying the embodiment of the present invention.
14 in that microcomputers 264 and 269, a transmission module 301, and a reception module 302 are provided. In order to perform transmission power control, the AMP 109 (see FIG. 22) of the transmission module 301 and the DC bias circuit 110
(See FIG. 22) can be externally controlled, and the amplification factor and the DC bias value can be changed by the microcomputer 264, respectively.

The basic operation is as follows.
2 is used to control the transmission power of the transmission module 301 so that necessary and appropriate reception power is obtained. For this reason, the receiving module 302 needs a means for detecting the received power.

FIG. 22 is a block diagram showing one embodiment of the transmission module shown in FIG. 21, and FIG. 23 is a block diagram showing one embodiment of the reception module shown in FIG. As shown in the receiving unit 302 of FIG. 23, a detection circuit 95 may be provided to detect the received power.

The detection circuit 95 may be configured as shown in FIG. 24, for example. FIG. 24 is a circuit diagram showing one embodiment of the detection circuit of FIG. In FIG. 24, 18
8 is a buffer, 189 is a diode, 190 is a resistor, 1
Reference numeral 91 denotes a capacity, and 192 denotes an AMP. HPF1 of FIG.
At 4, only the frequency components necessary for the luminance signal Y are extracted and the signal is input to the detection circuit 95. In the detection circuit 95, an output corresponding to the reception level is obtained at both ends of the resistor 190 by a parallel circuit of a resistor 190 and a capacitor 191 which are half-wave rectified by a diode 189, amplified by an AMP 192, and then amplified by a microcomputer 26.
9 (see FIG. 21B), the level is fetched. The microcomputer 269 monitors the state of the reception level, and requests the transmission unit 161 to increase the transmission power when the reception level decreases. The microcomputer 264 of the transmission unit 161 increases the amplitude with the AMP 109 in response to the request for increasing the power, and controls the DC bias circuit 110 to increase the DC bias current of the infrared LED 11 to increase the transmission power. In the case of a request to lower the transmission power, the operation is reversed.

By performing the transmission power control described above, when the distance between the transmission unit 161 and the reception unit 162 is large, the transmission power is increased to increase the transmission quality, and when the distance is short, the transmission power is suppressed to reduce waste of power. It is possible to maximize the performance with respect to the power saving and realize an environment-friendly system that does not consume unnecessary power. In addition, since the video / audio transmission method is the same as that of the third embodiment, the detailed description is omitted.

Next, high-speed data transmission and multi-channel data transmission using infrared rays will be described with reference to FIG. FIG. 25 is a block diagram showing a fifth embodiment of the wireless transmission / reception system according to the present invention. In the figure, a transmission block includes a serial / parallel conversion unit 401, a parallel input unit 403, a parallel register unit (or a buffer unit).
391, FSK modulation section (encoder section) 393, BPF
Unit 409, addition circuit (frequency multiplexing unit) 411, infrared LE
D413. The reception block includes a PD (light receiving unit) 415, a preamplifier unit 417, a BPF unit (multiplexed signal separation unit) 419, an FSK demodulation unit (decoder) 395, a parallel register unit 397, and a parallel / serial conversion unit 4.
25, and a parallel output unit 427. The input serial data D0 to Dn are converted by the serial / parallel converter 401 into n-bit parallel data.
This data is transmitted to an FSK modulator 39 composed of a VCO.
3 and FSK modulated according to the data. The free-run frequency of the VCO constituting the modulation section 393 is n
Everything is different so that bits of data can be transmitted simultaneously. The FSK-modulated data is filtered by a BPF unit 409 to remove unnecessary signals so that harmonics and modulation waves of each VCO do not interfere with each other, and then an adder (frequency multiplexing unit) 411 is used.
And emitted by the infrared LED 413 as infrared light.

In the receiving block, the signal is converted into an optical-electric signal by a PD (pin photodiode) 415. This data is amplified by the preamplifier unit 417 to an amplitude that allows the operation of the demodulation unit. After that, frequency separation is performed by the BPF unit 419 so that each frequency does not interfere.
Each modulated wave data is subjected to FS by a demodulation unit (decoder) 395.
K-modulated and demodulated to a baseband digital signal,
The data is converted into serial data by a parallel / serial conversion unit 425 via a parallel register unit (or buffer unit) 397, and the original baseband digital data is obtained. The parallel input unit 403 and the parallel register 391 constitute a serial / parallel converter, and the parallel register 397 and the parallel output unit 427 constitute a parallel / serial converter. As described above, according to the present invention, a large number of digital data can be transmitted simultaneously, and high-speed data communication can be realized.

FIG. 26 is a block diagram showing a sixth embodiment of the radio transmission / reception system according to the present invention. In the illustrated spatial transmission system using infrared light, a transmission block includes a serial / parallel conversion unit 401, a parallel input unit 403,
It comprises a parallel register section (or buffer section) 405, a modulation section (encoder section) 407, a BPF section 409, an addition circuit (frequency multiplexing section) 411, and an infrared LED 413. The reception block includes a PD (light receiving unit) 415, a preamplifier unit 417, a BPF unit (multiplexed signal separation unit) 419, a demodulation unit (decoder) 421, a parallel register unit 423, a parallel / serial conversion unit 425, and a parallel output unit 427.
Consists of Input serial data D0 to Dn
Is converted into n-bit parallel data by a serial / parallel converter 401. This data is input to a modulating unit 407 composed of a VCO, and PSK is
Modulated. The free-run frequencies of the VCOs constituting the modulator 407 are all different so that n-bit data can be transmitted simultaneously. For example, the free-run frequency F of each VC0 is, for example, F0 = 10 MHz, F1 = 20M
Hz, F2 = 30 MHz,... F8 = 80 MHz. The PSK-modulated data is filtered by an adder (frequency multiplexing unit) 411 to remove unnecessary signals by a BPF unit 409 so that harmonics and modulated waves of each VCO do not interfere with each other. Radiated.

In the receiving block, the signal is converted into an optical-electric signal by a PD (pin photodiode) 415. This data is amplified by the preamplifier unit 417 to an amplitude that allows the operation of the demodulation unit. After that, frequency separation is performed by the BPF unit 419 so that each frequency does not interfere.
Each modulated wave data is demodulated to a baseband digital signal by a demodulation unit (decoder) 421, converted to serial data by a parallel / serial conversion unit 425 via a parallel register unit (or buffer unit) 423, and converted to an original baseband signal. Digital data of the band is obtained. Note that a serial / parallel conversion unit is configured by the parallel input unit 403 and the parallel register 405, and the parallel register 423
The parallel output unit 427 forms a parallel / serial conversion unit.

Regarding the transfer speed, the VCO of the modulation unit 407
In the case of free run setting. For example, if the update speed of the register 405 is 2.5 MHz, the total transfer speed is 2.5 M
Hz × 16 bits = 40 Mbps. Although it is conceivable to directly drive the VCO of the demodulation unit 407 with 40 Mbps serial data, when performing high-speed modulation with one VCO,
VCO, infrared LED413, PD41 with speeding up
5 is required, the individual circuit elements become special and expensive, resulting in an unrealistic system in terms of cost. The present system can easily realize a wireless transmission / reception system by reducing these burdens.

In the wireless transmission / reception system of this embodiment, even if the data connected thereto is parallel data, the parallel input section 403 and the parallel register 4
With the combination of 05, parallel data can be directly input. Further, in the present wireless transmission / reception system, transmission of different channels is also possible. In this case, data of a plurality of channels can be transmitted at the same time, and multi-channel infrared space transmission becomes possible.

In the embodiment shown in FIG.
Since 4-PSK modulation (phase modulation) is incorporated in the demodulation unit 421, the data transfer amount can be doubled as compared with the FSK modulation in FIG. This makes it possible to equivalently double the number of channels as compared with the embodiment of FIG.

FIG. 27 is a block diagram showing a seventh embodiment of the radio transmission / reception system according to the present invention. In the configuration of FIG. 27, the same blocks as those in FIG. 25 are denoted by the same reference numerals, and description thereof will be omitted. In FIG. 27, the luminance signal Y and the color difference signals Pb and Pr pass through the AMP and clamp circuits 431a, 431b and 431c and the pre-emphasis circuits 433a, 433b and 433c, respectively.
Modulated by the modulation circuits 435a, 435b and 435c,
The frequency is separated by the PFs 437a, 437b, and 437c, added by the adder 411, and transmitted from the infrared LED 413. In the receiving block, the light is received by the PD 415, converted into an electric signal, amplified by the preamplifier 417, and
39a, 439b, 439c via the demodulation circuit 441
a, 441b, and 441c are demodulated into analog signals. Luminance signal Y and color difference signal P converted into analog signals
b, Pr are de-emphasis circuits 443a, 443b,
443c, clamp circuit and AMP 445a, 445
b, 445c, driver circuit and AMPs 447a, 44
The original luminance signal Y and color difference signals Pb and Pr are output to the respective terminals through 7b and 447c.

In the present embodiment, a multi-channel transmission system capable of transmitting and receiving data in combination with other data and analog signals other than the luminance signal Y and the color difference signals Pb and Pr can be constructed. A plurality of transmission / reception channels are provided and transmission is performed. For example, three channels are assigned to transmission of video signals Y, Pb, and Pr, and a AMP for adjusting a deviation, a clamp circuit as necessary, and a reduction in FM transmission noise. Pre-emphasis circuit, de-emphasis circuit, modulation / demodulation circuit, BPF for eliminating the influence of adjacent channels, and driver A
It has an MP. Other channels other than video are used for data channels, and in the figure, it is possible to transmit 5 bits in parallel. In addition to parallel data transmission, this data can also transmit completely different data for each channel. For example, it is possible to transmit digital data of audio 4 ch, and to transmit audio data such as a bit stream such as delta-sigma modulation. . For example, in this embodiment, in addition to the video signal, audio signals in multiple languages,
A system capable of simultaneously transmitting five channels of surround sound or the like can be easily constructed. As described above, in this embodiment, a multi-channel signal can be added in the same manner, and a system for simultaneously transmitting signals can be easily realized. Also,
A high-speed data transmission system can be easily realized.

Hereinafter, referring to FIG. 28, a high definition video signal (luminance signal Y, color difference signals Pb, Pr or R, G, B)
An LED driver circuit for performing frequency multiplexing by the current addition method will be described. FIG. 28 is a circuit diagram showing one embodiment of an LED driver circuit used in the wireless transmission / reception system according to the present invention. In the figure, this LED driver circuit outputs an output AM of a luminance signal Y and color difference signals Pb and Pr.
P, a block of current addition AMP. AMP
451a, AMP451b, AMP451c are RF-A
MP, and its input terminals are a luminance signal Y and a color difference signal P.
b, Pr or FM carrier frequency modulated with R, G, B baseband (for example, 80 MHz ± Δf1,
50 MHz ± Δf2, 30 MHz ± Δf3) are input. After each signal is subjected to processing such as amplification, V1, V2,
It is output as V3. AMP 451a, 451b, 4
The output of 51c is supplied to output transistors Q1, Q2, Q3 via capacitors C4, C5, C6, respectively.
The current is converted. DC collector bias current values are mainly set by the resistors R1, R2, and R3, and the respective AC signals of the parallel circuits of the resistors R4 and R1, the parallel circuits of the resistors R5 and R2, and the parallel circuits of the resistors R6 and R3 are set. The current is mainly determined. Further, the gain of each AMP constituted by the transistors Q1, Q2 and Q3 can be freely set. Also,
The signal currents of the transistors Q1, Q2, Q3 are injected into the emitter of the transistor Q4 in the current adding section. Transistor Q4 is a common base type transistor that enables broadband transmission, and its output can be connected to infrared LED 413, a resistor, or the like. In the figure, the capacitance C
1, C2 and C3 are the transistors Q1, Q2 and Q3 and the emitter capacitance. The transistor Q5 is a current stopping transistor connected to the emitter of the transistor Q4, and the transistors Q6 and Q7 are transistors for applying a bias to the base of the transistor Q5.

In the adder circuit of the conventional LED driver circuit, for example, the luminance signal Y and the color difference signals Pb and Pr are added by one voltage addition AMP. This is tripled and is limited by the dynamic range of the AMP itself, so that waveform clipping and the like occur. In addition, since the signal amplitude increases, the slew rate of the AMP becomes a problem, the response is deteriorated in wide-band, large-amplitude operation, and the harmonic distortion becomes large. Affect.

On the other hand, in this embodiment, the AMP45
1a, 451b, 451c and transistors Q1, Q2, Q3 constituting the output AMP are connected to a luminance signal Y and a color difference signal P.
b, Pr, the operating range of each AMP is as compared to the case where voltage addition is performed with one AMP,
Since the signal amplitude is only about 1/3, a sufficient margin can be provided for the dynamic range. Further, since the amplitude value is small, the slew rate becomes good, and high-speed response can be ensured. Further, an AMP composed of transistors Q1, Q2 and Q3
Since the gain of the output AMP can be set freely, the output level can be easily optimized. For example,
It can also be used for automatic adjustment of output level. The output current of the output AMP is the collector current of the transistors Q1, Q2, Q3. The output current is injected from the collectors of the transistors Q1, Q2, Q3 to the emitter of the transistor Q4, and the current is added. As a result, since there is no amplitude in voltage, there is no problem of insufficient dynamic range in the final adder, and a wideband multiplex system can be easily realized. As the addition input, data addition can be performed in addition to the video signal.

As described above, according to this embodiment, in the LED driver circuit of the infrared transmission system, when adding the luminance signal Y, the color difference signals Pb, Pr or RGB signals, or a plurality of signals, the current addition method is used. As a result, addition can be easily performed without being restricted by the dynamic range, and the system can be simplified.

Next, the infrared video transmission signals HDTV and SD
An embodiment of automatic switching of TV signals will be described with reference to FIG. FIG. 29 is a block diagram showing an embodiment of an automatic transmission mode switching circuit used in the wireless transmission / reception system according to the present invention. In the figure, 471 is PD, 473,
475 is a pre-AMP for input signal amplification, and 477 is an HDTV.
BPF for carrier signal band pass, 483 for BPF for SDTV carrier signal band pass, 479 for circuit circuit for HDTV carrier detection (DET1), 485 for circuit for SDTV carrier detection (DET2), 481 and 487 for variable detection sensitivity (Vth ) Is a control signal detection comparator (COMP1, COMP2), 489 is a mode switching selection logic circuit, 491 is a microcomputer for holding or muting the mode when the light receiving signal is temporarily cut off, and 499 is a demodulation. Switching of delay amount of circuit 497 and HDTV or SDTV
A mode switching SW unit (SW1) for switching demodulation sensitivity,
Reference numeral 493 denotes a path switching SW for switching output signal paths (HDTV and SDTV) from the BPF 477 and the BPS 483.
A section (SW2) 501 is a mute SW section (SW3) operated by a control signal from the microcomputer 491. In addition, 4
95 is an AMP. Further, a time constant circuit may be used instead of the microcomputer 491.

The demodulation circuit 497 used in the present embodiment delays the signal in accordance with the modulated wave of the carrier as shown in FIG. 3 in order to secure linearity in a high frequency band and a wide band. And a pulse count detection method of demodulating using exclusive OR (ExOR). However, it is difficult to perform demodulation of all bands with the same circuit constant value. In this case, it is necessary to optimize the delay amount and the sensitivity in accordance with the reception frequency. Since the HDTV and SDTV proposed this time have different transmission bands, it is necessary to switch the amount of delay and sensitivity according to each transmission band.

In order to select this mode, AMP4
75 output BPF 47 for HDTV transmission signal band pass
7. The BPF 483 for passing the SDTV transmission signal band, the detection circuit 479 for the HD modulated wave carrier, and the SDTV modulated wave carrier detection circuit 485 are used. Further, comparators 481 and 487 are used to output the presence or absence of the HDTV carrier signal and the SDTV carrier signal.

The PD 471 converts the infrared light of the HDTV carrier or the SDTV carrier into an electric signal.
It is configured to be of a type that can operate in a wider band as it can pass V carriers.

FIG. 30 shows a BPF and an SDTV for HDTV.
FIG. 4 is a frequency characteristic diagram of a BPS for use, in which the horizontal axis represents frequency and the vertical axis represents pass characteristics. The BPF 477 has a bandwidth of F1 to F2, and allows only the SDTV carrier signal to pass therethrough.
483 has a bandwidth of F3 to F4, HDTV
Pass only the carrier. This BPF 477, 483
It is assumed that a sufficient amount of attenuation can be secured so that the carriers do not affect each other. (In the case of an AGC-AMP configuration in which the preamplifier gain is variable according to the light receiving current, the BPFs 477 and 483 can be used for both AGC control and mode switching.) The signal passing through the BPFs 477 and 483 is a detection circuit 479. , 487, and outputs a determination signal for determining the presence or absence of a carrier. The detection circuits 479 and 485 are composed of waveform rectification and smoothing circuits, output as DC voltages, and output from the comparators 481 and 485.
87 is input. The threshold values of the comparators 481 and 487 are set so as to prevent malfunction due to noise, and have a hysteresis. For example, HDT
When there is a V carrier signal, the output of the comparator 481 becomes “H” level, and when there is no carrier, “L”
Become a level. When there is an SDTV carrier, the output of the comparator 487 becomes "H" level, and when there is no carrier, it becomes "L" level. This output is input to the mode selection circuit 489. For example, the comparator 48
The outputs of 1, 487 are (1) H, L, (2)
A combination of L, H, (3) L, L, (4) H, H is conceivable. This mode selection circuit 489 is constituted by a logic circuit. For example, in the case of (1), the HDTV transmission mode,
(2) SDTV transmission mode, (3) no signal,
(4) assigns a priority (HDTV mode). (1),
In the case of (4), the control signal X terminal which is the output of the selection logic circuit 489 becomes “H”, and the sensitivity of the demodulation circuit 497, the mode switching SW 499 and the switching SW 493 for switching the signal path from the BPF are set to the A side ( HDTV mode side).

Similarly, in the case of (2), the selection logic circuit 4
89, the output X terminal becomes “L”, and SW499, SW4
93 is the B side (SDTV mode) side. (3) SD
If there are no TV and HDTV carrier signals, the Y terminal of the output of the selection circuit becomes "H", and the output SW 501 of the demodulation circuit 497 is on the mute side, and is in a mute state.
(If the Y terminal is HDTV or SDTV signal,
L "). During transmission operation, 1
Next, when the infrared transmission is interrupted, the states of SW499 and SW493 are maintained via the microcomputer 491 until the interruption is restored, and the SW501 is muted to prevent the output video image from becoming noise. Whether or not this interruption is a primary interruption is determined by the output state of Y. For example, the signal of Y changes in a short time and the original state (L->H-> L)
If it returns, it judges that it is the primary cutoff, SW499, SW493
Is kept in the state before the cutoff, and the mute is released after a certain period of time so that a stable reception state is maintained. Y
When the H signal (no carrier) continues to some extent, the mute state is maintained.

The mute control signal (external control signal) output from the microcomputer 491 is, for example, a blue screen or a TV until the light receiving mode is stabilized.
It can also be used as a control signal for holding the mode before shutting down in a memory or the like in the inside. As described above, in the present embodiment, the high-definition infrared video signal transmission (HDT
V) and an SDTV infrared transmission receiving system can be easily shared, and the system configuration can be simplified.

In the wireless transmission / reception system according to the present invention, spatial transmission using infrared rays has been described as an example. However, the transmission system is not necessarily limited to spatial transmission using infrared rays. Or a high-frequency radio wave method using a copper wire.

Although the description has been made using Pb and Pr as the color difference signals, the color difference signals are equivalent to RY and BY and may be expressed as Cb and Cr. Pb, Pr or C
The difference in the notation of b, Cr, etc. is mainly the difference in the matrix coefficient when the color difference signal is generated, and it is added that the essential meaning of the color difference signal does not change. As mentioned above,
ADVANTAGE OF THE INVENTION According to this invention, a practical system can be constructed | assembled in image and audio | wireless wireless transmission, and the realization of a system which is easy for a user to use becomes possible.

[0069]

As described above, according to the present invention, a plurality of signals or data can be transmitted through one transmission line.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a first embodiment of a wireless transmission / reception system according to the present invention.

FIG. 2 is a block diagram showing one embodiment of an FM modulation circuit used in the present invention.

FIG. 3 is a circuit diagram showing an embodiment of an FM demodulation circuit used in the present invention.

4 is a main part waveform diagram of the FM demodulation circuit shown in FIG. 3;

FIG. 5 is a characteristic diagram illustrating a first example of frequency characteristics of a luminance signal and a color difference signal.

FIG. 6 is a characteristic diagram illustrating a second example of frequency characteristics of a luminance signal and a color difference signal.

FIG. 7 is a characteristic diagram illustrating a third example of frequency characteristics of a luminance signal and a color difference signal.

FIG. 8 is a characteristic diagram illustrating a frequency characteristic of a luminance signal and a color difference signal according to a fourth embodiment.

FIG. 9 is a block diagram showing a second embodiment of the wireless transmission / reception system according to the present invention.

FIG. 10 is a circuit diagram showing one embodiment of a synchronizing signal superimposing circuit used in the present invention.

11 is a main part waveform diagram of the synchronization signal superimposing circuit shown in FIG. 10;

FIG. 12 is a circuit diagram showing one embodiment of a sync separation circuit used in the present invention.

13 is a main part waveform diagram of the synchronization signal separation circuit shown in FIG. 12;

FIG. 14 is a block diagram showing a third embodiment of the wireless transmission / reception system according to the present invention.

FIG. 15 is a block diagram showing one embodiment of a transmission / reception module used in the wireless transmission / reception system shown in FIG.

FIG. 16 is a block diagram showing an embodiment of a receiving module used in the wireless transmission / reception system according to the present invention.

FIG. 17 is a circuit diagram showing an embodiment of an ASK modulation circuit used in the present invention.

18 is a main part waveform diagram of the ASK modulation circuit shown in FIG.

FIG. 19 is a circuit diagram showing an embodiment of an ASK demodulation circuit used in the present invention.

20 is a main part waveform diagram of the ASK demodulation circuit shown in FIG. 19;

FIG. 21 is a block diagram showing a fourth embodiment of the wireless transmission / reception system according to the present invention.

FIG. 22 is a block diagram illustrating an example of a transmission module illustrated in FIG. 21.

FIG. 23 is a block diagram showing one embodiment of a receiving module shown in FIG. 21;

FIG. 24 is a circuit diagram showing one embodiment of the detection circuit of FIG. 23;

FIG. 25 is a block diagram showing a fifth embodiment of the wireless transmission / reception system according to the present invention.

FIG. 26 is a block diagram showing a sixth embodiment of the wireless transmission / reception system according to the present invention.

FIG. 27 is a block diagram showing a seventh embodiment of the wireless transmission / reception system according to the present invention.

FIG. 28 is a circuit diagram showing an embodiment of an LED driver circuit used in a wireless transmission / reception system according to the present invention.

FIG. 29 is a block diagram showing an embodiment of an automatic transmission mode switching circuit used in the wireless transmission / reception system according to the present invention.

FIG. 30: BPF for HDTV and BPF for SDTV
3 is a frequency characteristic diagram of FIG.

[Explanation of symbols]

1 ... transmission block, 2 ... reception block, 2, 3, 4 ... F
M modulation circuit, 5, 14,... HPF, 6, 7, 15, 164
19 BPF, 8, 411 Adder circuit, 9, 13 AM
P, 10 ... DC bias circuit, 11 ... Infrared LED, 1
2, 415 ... PD, 17, 18, 19 ... FM demodulation circuit,
40: synchronization signal superimposing circuit, 41: synchronization separation circuit, 64
69 microcomputer, 201 transmission module, 202 reception module, 401, 425 serial / parallel converter, 391, 397 parallel register, 393 F
SK modulator, 409 BPF section, 417 pre-AMP
Section, 395: demodulation section, 479, 485: detection circuit, 48
9: Mode switching selection logic circuit.

Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat II (reference) H04B 10/00 H04N 7/08 Z H04J 1/08 H04B 9/00 R H04N 5/40 C 5/44 5/455 ( 72) Inventor Satoshi Sekiguchi 2-5-5 Keihanhondori, Moriguchi-shi, Osaka Sanyo Electric Co., Ltd. (72) Inventor Seiwa Kadom 2-5-2-5 Keihanhondori, Moriguchi-shi, Osaka Sanyo Electric Co., Ltd. In-house F term (reference) 5C025 AA11 BA09 BA11 DA01 DA10 5C063 AA01 AA06 AB06 AB20 AC01 CA03 CA31 5K002 AA02 AA04 BA14 DA08 DA21 FA03 GA01 5K022 AA03 AA10 AA12 AA23 AA32 AA33

Claims (15)

[Claims] 1. A modulator for modulating a plurality of information comprising a plurality of signals or a plurality of data, a filter for filtering the modulated information, and multiplexing the filtered information. A multiplexing unit, a transmission block having a transmitting unit for wirelessly transmitting the multiplexed information, a receiving unit for receiving the multiplexed information, and filtering the received information. A radio transmission / reception system, comprising: a filter section for performing frequency separation and a reception block having a demodulation section for demodulating each of the frequency-separated information. 2. A transmitter comprising a transmitter and a receiver, the transmitter comprising: a modulator for modulating a plurality of video signal components;
A filter unit for filtering the plurality of modulated video signal components, a multiplexing unit for multiplexing the filtered plurality of video signal components, and the multiplexed video signal components A receiving unit corresponding to the transmitting unit for receiving the plurality of video signal components, and a plurality of video signal components received by the receiving unit. A wireless transmission / reception system, comprising: a filter unit that performs wave filtering; and a demodulation unit that demodulates the filtered plurality of video signal components and reproduces the video signal components. 3. A transmission section comprising a transmission section and a reception section, wherein the transmission section superposes a predetermined video signal component and a synchronization signal, and the predetermined video signal component and the predetermined video signal component are superimposed on the synchronization signal. A modulating unit that modulates each of the video signal components, a filter unit that filters each of the modulated plurality of video signal components and the video signal component on which the synchronization signal is superimposed, and a filtered signal. And a transmitting unit driven by the multiplexed signal. The receiving unit includes a receiving unit corresponding to the transmitting unit, and the plurality of images received by the receiving unit. A filter unit that filters and separates the video signal component on which the signal component and the synchronization signal are superimposed; and a plurality of video signal components separated by the filter unit and the video signal component on which the synchronization signal is superimposed. A demodulation unit for demodulating and a video signal on which the synchronization signal is superimposed Radio transmission and reception system, characterized in that it comprises a synchronization separating means for separating a synchronizing signal minutes. 4. A transmitting unit comprising: a transmitting unit; and a receiving unit, wherein the transmitting unit modulates each of a plurality of video signal components, an audio modulating unit that modulates an audio signal, and a second modulating unit that modulates a data signal. 1 data filtering means, filtering each of the video signal components modulated by the video modulation section, the audio signal modulated by the audio modulation section, and the data signal modulated by the data modulation section. A filtering unit, a multiplexing unit for multiplexing the filtered signals, a first transmission unit driven by the multiplexed signal, and a second data demodulation unit for reproducing a data signal. Wherein the receiving unit comprises: a first receiving unit corresponding to the first transmitting unit; a filter unit for filtering and separating a signal received by the first receiving unit; A video signal for demodulating a plurality of video signal components and reproducing the video signal components. A demodulator, an audio demodulator for demodulating and reproducing the filtered audio signal, a first data demodulator for demodulating and reproducing the filtered data signal, and a first data demodulator for modulating the data signal. 2 data modulating sections, and a second transmitting section driven by an output signal of the second data modulating section,
Further, the transmitting unit includes a second receiving unit corresponding to the second transmitting unit, a data signal filtering unit for filtering the data signal received by the second receiving unit, and a data signal filtering unit. A second data demodulator for demodulating the filtered modulated signal to reproduce a data signal. 5. The wireless transmission / reception system according to claim 4, wherein said reception section detects reception power and controls said transmission section to perform negative feedback control of transmission power. 6. A modulator for modulating a plurality of data having different transmission bands, a filter for filtering the modulated data, an adder for adding the plurality of filtered data, A wireless transmission apparatus for spatially transmitting the multiplexed data using infrared rays. 7. The radio transmission apparatus according to claim 6, wherein said modulator modulates the phase of each data. 8. The wireless transmission device according to claim 6, further comprising: a serial-parallel conversion unit that converts the plurality of serial data into parallel data; and a data register unit.
A wireless transmission device, wherein data output from the data register unit is modulated by the modulation unit. 9. The wireless transmission apparatus according to claim 6, wherein said plurality of data is a high definition infrared video signal component and other data. 10. The wireless transmission device according to claim 6, wherein
The plurality of data are a luminance signal Y, a color difference signal Pb, Pr, or a baseband signal of R, G, B, and the adding section performs current addition. 11. A radio transmission apparatus according to claim 10, wherein said adding section independently amplifies said luminance signal Y, said color difference signals Pb, Pr or said R, G, B baseband signals. A wireless transmission device provided with a circuit, wherein an output section of the amplifier circuit uses a current addition method. 12. A receiving section for modulating a plurality of data having different transmission bands, receiving a multiplexed transmitted data, a filter section for filtering the received plurality of data and frequency separating the data. A receiving unit having a demodulation unit for demodulating each of the frequency-separated data. 13. The wireless receiving apparatus according to claim 12, wherein the plurality of data are an HDTV video signal and an SDTV.
A wireless receiving device comprising a detecting unit for detecting an HDTV video signal and an SDTV video signal spatially transmitted by infrared light, which is one or both of the video signals for use, and capable of automatically switching to any of the reception modes. 14. The wireless transmission apparatus according to claim 12, wherein said plurality of data are an HDTV video signal and an SDTV.
Band signal for SDTV video carrier signal, band filter for SDTV video carrier signal, detector for detecting the output of each filter, demodulation band of the demodulator, sensitivity, etc. And a mode switching unit for switching between the two modes. 15. The wireless transmission apparatus according to claim 14, wherein one or both of the HDTV video signal and the SDTV video signal or infrared light transmitted by infrared light is 1 or more.
A radio receiving apparatus comprising: a circuit for judging that the signal has been cut off next, holding a mode, and controlling output mute.