JPH0946316A - Radio system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the quality of a radio transmission line, to reduce the scale of a large capacity data transmitting side circuit and to attain low power consumption by transmitting a high speed information signal by a spread spectrum system at the time of transmitting large capacity data. SOLUTION: Large capacity data outputted from an input device 11 or a storage device 12 are processed as data suitable for radio transmission by a radio equipment 1. The processed data are converted into a high speed spread spectrum signal by a transmission part 3 and sent from an antenna 7. In a radio equipment 2, a signal transmitted from the equipment 1 is received by an antenna 9 and demodulated to the original information signal by a receiving part 5 and the original information signal is outputted to an output device 13 or a storage device 14. Since the spread spectrum modulation system is adopted to signal modulation, stable transmission quality capable of reducing its data errors as compared with normal radio transmission can be obtained.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a wireless system, and more particularly, to unidirectional wireless transmission of a large amount of data such as image signal transmission of a digital video camera, sharing of a printer, sharing of stored information, etc. About the system to do.

[0002]

2. Description of the Related Art When it is attempted to construct a wireless transmission system for large-capacity information, such as video compression of a moving image captured by a digital video camera and wireless transmission, large-capacity data can be transmitted wirelessly at high speed and with high quality. As a method of transmitting to
As disclosed in JP-A-5-112814,
A wireless transmission system using a spread spectrum communication system used for a wireless LAN is known.

The spread spectrum system is a system in which a signal is spread over a wide band and transmitted by a radio wave having a low power density. Since the power density is low, it is difficult to cause interference with other devices and receives interference from other devices. It has features such as difficulty, difficulty in receiving radio wave environment such as phasing, etc.

[0004]

By the way, in the above-mentioned conventional example, both the information data and the control data are transmitted by a high-speed spread spectrum signal, but a system for wirelessly transmitting a moving image of a digital video camera or the like. In order to build the above, it is required for the camera side to have a small circuit and low power consumption for battery driving.

In the spread spectrum modulation method, since the information data to be transmitted is spread over a wide band by a spreading code using a clock faster than the speed of the information and is transmitted, when the speed of the information data to be transmitted becomes high, In proportion to this, the clock speed of the spread processing signal becomes high, and in particular, the receiving side needs a high-speed operation for the signal processing circuit to demodulate the original information signal by correlating the modulation signal sent and the code. Therefore, there is a problem that the circuit configuration of the demodulation signal processing unit becomes complicated and power consumption increases.
Further, when performing transmission and reception at the same time, there is a problem that a wide transmission band is required for each of transmission and reception.

[0006]

For example, when considering a configuration in which image information taken by a video camera is wirelessly transmitted to a VTR, the information transmitted from the camera to the VTR is a large amount of image data, but The information transmitted to the camera may be data having a small amount of information such as a control signal and a status display signal.

Therefore, in the present invention, the signal sent from the camera to the VTR is a high-speed modulation signal using a spread spectrum modulation method that has good transmission quality and enables high-speed data transmission. However, the control signal transmitted from the VTR to the camera is used. In order to solve the above-mentioned problems, a low-speed modulated signal is used for the wireless communication, and a wireless system having different transmission rates for transmission and reception is constructed.

[0008]

By transmitting the image information at high speed using spread spectrum modulation, good transmission quality can be obtained, and by using the low speed modulation signal as the control signal, the signal processing speed in the receiving circuit can be slowed down. It is possible to achieve low power consumption. Further, since the data transmission rate and the wireless transmission bandwidth are proportional to each other, by using a low speed modulation signal for the control signal, the transmission bandwidth for transmitting the control signal can be narrowed and the frequency efficiency can be improved.

[0009]

The details of the present invention will be described below with reference to the illustrated embodiments. FIG. 1 is a configuration diagram of a wireless system according to a first embodiment of the present invention. In the figure, 1 is a wireless device that sends high-speed data, 2 is a wireless device that sends low-speed data, 3 is a wireless transmission unit that sends high-speed data, 4
Is a wireless reception unit for receiving low-speed data, 5 is a wireless reception unit for receiving high-speed data, 6 is a wireless transmission unit for transmitting low-speed data, and 7, 8, 9, 10 are for transmitting or receiving wireless signals. Is an input device such as a video camera or a personal computer, 12 is a storage device such as a data storage device, 13 is an output device such as a printer or a television monitor, and 14 is a storage device such as a VTR or a personal computer.

The large-capacity data output from the input device 11 or the storage device 12 is processed by the wireless device 1 into data suitable for wireless transmission, and converted into a high-speed spread spectrum signal by the transmission unit 3. , Is transmitted from the antenna 7. In the wireless device 2, the signal transmitted from the wireless device 1 is received by the antenna 9, demodulated into the original information signal by the receiving unit 5, and output to the output device 13 or the storage device 14.

In general, in wireless data transmission, an error is likely to occur in the transmission data due to the influence of multipath, an interfering signal, etc. Especially, the higher the speed of the data, the more frequently the error occurs. By adopting the spread spectrum modulation method, stable transmission quality with less data error is realized compared to normal wireless transmission.

On the other hand, from the wireless device 2, information on the receiving side such as the state of the output device 13 and the storage device 14 and the state of the received signal, or small capacity data such as control information for the input device 11 or the storage device 12, The transmitter 6 converts the low-speed modulated signal and sends it out from the antenna 10, and the wireless device 1 receives the signal sent from the wireless device 2 in the antenna 8. The receiving section 4 demodulates the control signal and processes it.

Since the receiving section 4 demodulates low-speed data, the signal processing circuit can be operated with low power consumption and can be applied to a battery-driven portable device or the like.

Although the transmitting section and the receiving section are separated from each other in FIG. 1, the same antenna may be used (this also applies to each of the following embodiments). The control signal is generated by the wireless device 2 or the output device 1.
3 and the storage device 14 can be used. Although not mentioned above, the high-speed signal transmitted from the wireless device 1 includes a control signal from the wireless device 1 to the wireless device 2 and the like. Also, the wireless devices 1 and 2 are
It is also possible to connect with a device not described in this embodiment.

FIG. 2 is a block diagram of a wireless system according to the second embodiment of the present invention, and this embodiment is an application example to a surveillance camera system and the like. In FIG. 2, those having the same functions as those in FIG. 1 are designated by the same reference numerals and their description is omitted.

In FIG. 2, reference numeral 15 is a digital video camera, 16 and 20 are information signals obtained by compressing a video signal taken by the camera into a moving image, 17 and 21 are control signals of the camera, and 18
Is a control device, 19 is an image monitor, and 22 is a normal video signal.

The video signal taken by the digital camera 15 is subjected to processing such as moving picture compression, is input to the radio apparatus 1 as the video information signal 16, is spread-spectrum-modulated by the transmitting unit 3, and is then transmitted to the antenna 7. Sent by. In the wireless device 2, the signal received by the antenna 9 is received by the receiving unit 5
After demodulating in and converting it into the original video information signal 20, the control device 18 converts it into the normal video signal 22, and the image monitor 1
Output to 9.

Further, a signal 21 for controlling the camera 15 for zooming, adjusting a photographing angle, etc. is sent from the control device 18.
Is input to the wireless device 2, modulated by the transmitter 6, and then transmitted from the antenna 10. In the wireless device 1, the signal received by the antenna 8 is demodulated by the receiving unit 4 into the control signal 17, which is transmitted to the camera 15 for control.

In the present system, stable transmission of data is possible even in a noisy environment such as FA by transmitting the video information signal after spread spectrum modulation. The transmission signal 16 of the transmission unit 3 is high-speed data because it is a video information signal, but the control signal 17 is low-speed data. Therefore, the demodulation processing of the reception unit 4 on the camera 15 side can have a relatively simple circuit configuration. Therefore, the circuit scale of the wireless device 1 on the camera 15 side can be reduced, and the size and power consumption can be reduced.

Although the number of cameras 15 is one in the embodiment shown in FIG. 2, it is also possible to construct a system for transmitting images of a plurality of cameras 15 while sequentially switching them by a control signal 21 from the control device 18. Further, in this embodiment, the camera 1
Although an example using a digital video camera is shown as 5,
The same effect can be obtained in a system that transmits a still image using a digital still camera or the like.

FIG. 3 is a block diagram of a wireless system according to the third embodiment of the present invention. In this embodiment, a video camera and a V
This is an application example to a system in which TRs are wirelessly connected. In FIG. 3, components having the same functions as those in FIGS. 1 and 2 are designated by the same reference numerals and their description is omitted. In FIG. 3, 23 is VT
R.

The video signal photographed by the video camera 15 is subjected to moving picture compression processing and the like together with the audio signal.
After superimposing a signal for controlling 23, the signal is input to the wireless device 1 as the information signal 16, spread-spectrum-modulated by the transmitter 3, and then transmitted from the antenna 7. In the wireless device 2, the signal received by the antenna 9 is demodulated and reproduced by the receiving unit 5 into the original information signal 20, input to the VTR 23, and the video signal is recorded on the tape in accordance with the control signal sent by being superimposed. To do.

On the other hand, from the VTR 23, the current setting state, the remaining amount of tape, other alarm information, etc. are input to the wireless device 2 as the control signal 21, and the modulated signal is transmitted from the antenna 10 by the transmitter 6. In the wireless device 1, the antenna 8
The signal received at 4 is demodulated into a control signal 17 by the receiving unit 4 and transmitted to the camera 15.

By adopting this system, it is possible to monitor whether the image being taken is normally recorded in the VTR 23 while operating the camera 15. Since the video camera 15 is battery-powered, the wireless device 1 is required to have low power consumption, and in order to constantly monitor the state of the VTR 23 even when images are not being transmitted, the receiving unit 4 is always operated. Therefore, low power consumption is especially required. In this embodiment, the video information signal 16 transmitted from the camera 15 is a high-speed signal, but the control signal 17 received is a low-speed signal, so that the power consumption of the receiver 4 can be reduced.

In the present embodiment, the system for controlling the VTR 23 on the video camera 15 side has been described. However, as in the second embodiment of FIG.
It is also possible to control 5.

FIG. 4 is a block diagram of a wireless system according to the fourth embodiment of the present invention. This embodiment is an example of application to a system for wirelessly connecting a personal computer or the like and a printer. In FIG. 4, those having the same functions as those in FIG.

In FIG. 4, 24 is a personal computer, 25 and 28 are information signals to be printed, and 26 and 29.
Is a control signal sent back from the printer, and 27 is a printer.

The print information signal 25 output from the personal computer 24 is spread-spectrum-modulated by the transmitter 3 of the radio apparatus 1 and then sent out from the antenna 7. In the wireless device 2, the signal received by the antenna 9 is demodulated into the information signal 28 by the receiving unit 5, and then the printer 27 prints out.

From the printer 27 or the wireless device 2,
The transmission unit 6 of the wireless device 2 modulates a control signal 29 such as communication control for transmission requests from a plurality of personal computers 24 and a retransmission request when the transmitted information signal contains an error. It is transmitted from the antenna 10. In the wireless device 1, the receiving unit 4 demodulates the signal received by the antenna 8 into the control signal 26 and controls communication.

In the present system, when printing a large amount of image data or image-processed data, wireless transmission can be performed at high speed, so that the wireless line can be used efficiently.
Further, since the control signal 26 transmitted from the printer 27 side is low-speed data, it is possible to reduce the power consumption during standby on the personal computer 24 side.

Although the personal computer 24 is used as the information transmission source in this embodiment, the same effect can be obtained by using a word processor or a handy terminal. or,
Although not described in detail in this embodiment, one printer 27 can be efficiently shared by a plurality of personal computers 24 by providing the wireless devices 1 and 2 with the buffer memory function and the communication control function of the wireless unit. You can

FIG. 5 is a block diagram of a wireless system according to the fifth embodiment of the present invention, and this embodiment is an example of application to a database sharing system. In FIG. 5, FIG.
Those having the same functions as those in FIG. 4 are designated by the same reference numerals and the description thereof will be omitted.

When a request signal 29 for taking out the data stored in the storage device 12 is input from the personal computer 24 to the wireless device 2, it is modulated by the transmitting section 6 and then transmitted from the antenna 10.

In the radio device 1, the signal received by the antenna 8 is demodulated into the request signal 26 by the receiving unit 4 and input to the storage device 12. In response to the request from the personal computer 24, the storage device 12 sends necessary data to the information signal 2
The signal is input to the wireless device 1 as 5, is spread-spectrum-modulated by the transmitting unit 3, and is then transmitted from the antenna 7.

In the radio unit 2, the signal received by the antenna 9 is demodulated into the information signal 28 by the receiving unit 5 and then transferred to the personal computer 24.

By adopting this system, it becomes possible for a plurality of personal computers 24 to share the database stored in the storage device 12. Further, in the present system, the data output from the storage device 12 is spread spectrum modulated and transmitted, so that high confidentiality can be obtained as compared with normal wireless communication.

In this system, it is necessary for the personal computer 24 side to receive a high-speed signal, but the receiving section 5 may be operated only when a data transmission request is issued from the personal computer 24 side, and it is necessary to always operate. Therefore, the average power consumption does not increase.

FIG. 6 and FIG. 7 show an example of the transmitting / receiving section used in the radio equipment of each embodiment of the present invention. In this example, a direct spread spectrum spread modulation method is used for high-speed transmission from the wireless device 1 to the wireless device 2, while a low-speed transmission from the wireless device 2 to the wireless device 1 is generally used. The frequency modulation (FM) method is adopted.

FIG. 6 is a circuit block diagram showing the configuration of the transmitting unit 3 and the receiving unit 4 of the wireless device 1 in FIG. 1, and FIG. 7 shows the configuration of the transmitting unit 6 and the receiving unit 5 of the wireless device 2. It is a circuit block diagram. 6 and 7, those having the same functions as those in FIG. 1 are designated by the same reference numerals and their description is omitted.

In FIG. 6, 30 is a transmitter / receiver of the radio apparatus 1, 31 is a circuit block of the transmitter 3, 32 is a circuit block of the receiver 4, 33 is a transmission data input terminal, 34 is a reception data output terminal, and 35 is Transmission data DPSK (Differ
entially encoded Phase Shift Keying) signal processing unit,
36 is an adder, 37 is a spread code generator, 38 is a reference signal generator, 39 is a multiplier circuit, 40 is a spread modulator, and 41, 4
2 is a band limiting unit, 43 is a transmission amplifying unit, 44 and 46 are receiving amplifying units, 45 and 48 are band limiting units, 47 is a frequency converting unit, 49 and 51 are IF amplifying units, 50 is a band limiting unit, and 52.
Is a demodulation unit for FM signals.

Further, in FIG. 7, reference numeral 53 is a transmitting / receiving unit of the radio apparatus 2, 54 is a circuit block of the receiving unit 5, 55 is a circuit block of the transmitting unit 6, 56 is a received data output terminal, 57 is a transmitted data input terminal, Reference numerals 58, 60 and 61 are reception amplification units,
Reference numeral 59 is a band limiting unit, 62 is a SAW matched filter for correlation demodulation, 63 is a SAW delay line, 64 is an amplifying unit, 65 is a delay detecting unit, 66 is a data reproducing unit, 67 is an FM modulating unit,
68 and 70 are transmission amplification units, and 69 is a band limiting unit.

First, transmission of a high-speed information signal from the wireless device 1 to the wireless device 2 will be described. First, the operation of the high-speed data transmission block 31 of the wireless device 1 on the transmitting side will be described with reference to FIG. Transmission data input terminal 3
The high-speed data input from 3 is the DPSK processing unit 35.
Then, after the signal processing is performed so that the phase of the carrier wave in the modulation section 40 becomes in-phase or anti-phase according to the transmission data, the spread code is generated in the addition section 36 by the reference clock generated by the reference signal generation section 38. It is added to the spread code generated in the unit 37 and input to the spread modulator 40. Further, the reference clock generated by the reference signal generation unit 38 is multiplied by the multiplication circuit 39, and then only the carrier signal is selected by the band limiting unit 41 and input to the spread modulation unit 40. By performing phase modulation on the signal output from the adder 36, the wideband spread spectrum modulation signal is generated, and the band limiting unit 42 suppresses unnecessary signal components, and then the transmission amplifier 43 outputs the specified signal. The level is adjusted and the signal is transmitted from the antenna 7.

Next, the operation of the reception block 54 of the radio apparatus 2 for receiving the high speed spread spectrum signal will be described with reference to FIG.
This will be described with reference to FIG. The reception signal input from the antenna 9 is amplified to a predetermined signal level by the reception amplification units 58, 60 and 61, the interference signal is suppressed by the band limiting unit 59, and then the SAW for correlation demodulation of the spread spectrum signal is performed.
It is input to the matched filter 62. In the SAW matched filter 62, the same code as the spreading code generated by the spreading code generator 37 in the transmission block 31 is created in advance as an electrode pattern. When the spreading signal is input, the SAW matched filter 62 outputs it. Outputs a pulsed correlation demodulation signal. The output signal of the correlation demodulated signal is input to the delay detection unit 65 via the amplification unit 64, and the signal delayed by one cycle of the spread code by the SAW delay line 63 is multiplied to perform delay detection. As described above, since the signal transmitted is previously processed by the DPSK signal processing unit 35 on the transmission side, the positive detection pulse signal or the negative detection pulse signal is present in the delay detection output depending on the transmission data. The received data is output and the received data is reproduced by determining the polarity of the detection signal in the data reproducing section 66, and is output from the received data output terminal 56.

In this example, by using the SAW matched filter 62 in the correlation demodulation unit of the spread spectrum signal, the spread spectrum high speed signal is efficiently demodulated with a relatively simple structure without performing complicated signal processing. be able to. However, other demodulation methods can be used depending on the purpose. In this example, direct modulation and direct demodulation without frequency conversion are used for both transmission and reception, but it is also possible to adopt a configuration for frequency conversion. or,
In the reception block 54, circuit blocks such as a clock recovery circuit that are incidental to the reception block 54 are omitted.

Next, the transmission of the low-speed control signal from the wireless device 2 to the wireless device 1 will be described. First, the operation of the transmission block 55 of the wireless device 2 on the transmission side will be described with reference to FIG. The low-speed control signal input from the transmission data input terminal 57 is frequency-modulated by the FM modulator 67, and then set to a prescribed transmission output level by the transmission amplifiers 68 and 70, and the band limiter 69. After suppressing unnecessary signal components, the signal is transmitted from the antenna 10.

In the reception block 32 of the wireless device 1, the reception signal input from the antenna 8 is received and amplified by the reception amplifiers 44 and 46.
After amplifying to a predetermined signal level by the band limiting unit 45 and suppressing unnecessary interference signals, the frequency converting unit 47 multiplies the reference clock of the reference signal generating unit 38 by the multiplying circuit 39 to limit the band. After being mixed with the reception local oscillation signal extracted by the unit 48 and converted into an IF signal, the amplification units 49, 5
1 to the FM demodulation unit 52 via the band limiting unit 50, and the demodulated reception signal is output from the reception data output terminal 34.

In this example, by adopting the spread spectrum system as the means for transmitting the high-speed information signal, the probability that the signal is erroneously transmitted can be suppressed to a low level even in a poor radio environment, and the control signal can be suppressed. By using a low speed signal,
The circuit on the side of the wireless device 1 can be made to have a simple configuration, and downsizing and low power consumption can be achieved. Further, since the information transmission from the wireless device 1 to the wireless device 2 is a high-speed transmission, a wide wireless transmission band is required, but the transmission from the wireless device 2 to the wireless device 1 is a low-speed transmission, and thus the required band is narrow. Therefore, the frequencies selected by the band limiting units 41 and 48 in FIG.
By selecting frequencies that do not interfere with each other, transmission /
Receiving enables simultaneous communication. In this example, the FM modulation system is used for data transmission from the wireless device 2 to the wireless device 1, but other systems such as the PSK modulation system may be used.

FIG. 8 and FIG. 9 show another example of the transmission / reception unit used in the radio apparatus of each embodiment of the present invention. In this example, a direct spread spectrum spread modulation method is used for both high-speed transmission from the wireless device 1 to the wireless device 2 and low-speed transmission from the wireless device 2 to the wireless device 1.

FIG. 8 is a circuit block diagram showing the configurations of the transmitting unit 3 and the receiving unit 4 of the wireless device 1 in FIG. 1, and FIG. 9 is the transmitting unit 6 and the receiving unit 5 of the wireless device 2 in FIG.
2 is a circuit block showing the configuration of FIG. In FIGS. 8 and 9, components having the same functions as those in FIGS. 1, 6 and 7 are designated by the same reference numerals and description thereof is omitted.

In FIG. 8, 71 is a circuit block of the receiving section 4, 72 is a synchronous detection section, 73 is an A / D conversion section, 74 is a correlation demodulation section, and 75 is a data reproduction section.

Further, in FIG. 9, 76 is a circuit block of the transmission unit 6, 77 is an addition unit, 78 is a spread code generation unit, and 79.
Is a reference signal generation unit, 80 is a multiplication circuit, 81 is a band limiting unit, and 82 is a spread modulation unit.

In this example, wireless device 1 to wireless device 2
The transmission of the high-speed information signal to and from is the same as the configuration of FIGS. 6 and 7, and therefore the description thereof is omitted.

In this example, the wireless device 2 to the wireless device 1
The transmission of a low speed control signal to the will be described next. The transmission block 76 in FIG. 9 has basically the same configuration as the transmission block 31. Transmission data input terminal 57
The input transmission signal is added by the adder 77 to the spread code generated by the spread code generator 78 using the reference clock of the reference signal generator 79, and input to the spread modulator 82. Further, the output signal of the reference signal generator 79 is multiplied by the multiplier 80, and then only the carrier signal is selected by the band limiter 81 and input to the spread modulator 82, where it is added to the spread code. After being spread-modulated by the control signal, the band limiting unit 69 removes unnecessary signal components, the amplifying unit 70 amplifies the signal to a predetermined signal level, and then the signal is transmitted from the antenna 10.

In the reception block 71 of FIG.
The received signal input to the amplifier is amplified to a predetermined signal level by the amplifiers 44 and 46, the interfering signal is suppressed by the band limiter 45, and then the received signal is input to the synchronous detector 72 to convert the phase-modulated signal. Synchronous detection demodulates the signal before modulation and A / D
After being converted into a digital signal by the conversion unit 73, the correlation demodulation unit 74 performs correlation demodulation by digital signal processing, and the data reproduction unit 75 reproduces the original control data and outputs it from the reception data output terminal 34. .

The reference signal of the reference signal generator 38 of the wireless device 1 and the reference signal of the reference signal generator 79 of the wireless device 2 are
By setting the frequencies so that they do not interfere with each other, it is possible to prevent deterioration of reception sensitivity due to signal leakage and the like, and to perform transmission and reception at the same time.

In the present example, as a method of spread spectrum correlation demodulation, the receiving circuit block 54 of the radio apparatus 2 carries out correlation demodulation using a SAW matched filter which is advantageous for high-speed signal processing, and performs delay detection into a baseband signal. In contrast to the conversion, the receiving circuit block 7 of the wireless device 1
In No. 1, since the signal speed is low, first the synchronous detection unit 72
The received signal is converted to a baseband signal at, the A / D converter 73 converts it to a digital signal, and then the correlation demodulator 74 performs correlation demodulation by digital signal processing using a method such as sliding correlation. are doing. In the digital correlation method, when the transmission speed becomes high, the processing speed becomes high and the power consumption increases, but the low-speed signal makes it possible to reduce the power consumption.

In this example, the spread spectrum modulation method is adopted for the transmission of the control signal at a lower speed than the examples of FIGS. 6 and 7, so that the communication control can be performed more reliably even in a poor radio environment. become.

[0058]

As described above, according to the present invention, in high-capacity data transmission, the quality of the wireless transmission line can be improved by transmitting the high-speed information signal by the spread spectrum method, and the control signal cannot be transmitted in the reverse direction. The low-speed transmission can reduce the circuit scale on the transmission side of large-capacity data and reduce power consumption.

[Brief description of drawings]

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

FIG. 2 is a block diagram showing a configuration of a wireless system (application example to a surveillance camera system) according to a second embodiment of the present invention.

FIG. 3 is a block diagram showing a configuration of a wireless system (application example to wireless moving image transmission between a video camera and a VTR) according to a third embodiment of the present invention.

FIG. 4 is a block diagram showing a configuration of a wireless system (application example to a printer sharing system) according to a fourth embodiment of the present invention.

FIG. 5 is a block diagram showing a configuration of a wireless system (application example to a database sharing system by a personal computer) according to a fifth embodiment of the present invention.

FIG. 6 is a block diagram showing an example of a configuration of a transmission / reception unit in the wireless device 1 according to each embodiment of the present invention.

FIG. 7 is a block diagram showing an example of a configuration of a transmission / reception unit in the wireless device 2 according to each embodiment of the present invention.

FIG. 8 is a block diagram showing another example of a configuration of a transmission / reception unit in the wireless device 1 according to each embodiment of the present invention.

FIG. 9 is a block diagram showing another example of the configuration of the transmission / reception unit in the wireless device 2 according to each embodiment of the present invention.

[Explanation of symbols]

 1 wireless device for sending high speed data 2 wireless device for sending low speed data 3 wireless transmitter for sending high speed data 4 wireless receiver for receiving low speed data 5 wireless receiver for receiving high speed data 6 wireless for sending low speed data Transmitter 7, 8, 9, 10 Antenna 11 Input device 12 Storage device 13 Output device 14 Storage device 15 Video camera 16,20 Information signal 17,21 Control signal 18 Control device 19 Image monitor 22 Video signal 23 VTR 24 Personal computer 25 , 28 Information signal 26, 29 Control signal 27 Printer 30 Transmitter / receiver section of wireless device 1 Circuit block of transmitter section 32 Circuit block of receiver section 33 Transmitted data input terminal 34 Received data output terminal 35 DPSK signal processing section 36 Adder section 37 Spread Code Generator 38 Reference Signal Generator 9 multiplication circuit 40 spreading modulation unit 41, 42, 45, 48, 50 band limiting unit 43, 44, 46, 49, 51 amplification unit 47 frequency conversion unit 52 FM demodulation unit 53 transmission / reception unit of wireless device 2 54 reception unit 5 Circuit block 55 Circuit block of transmitter 6 56 Reception data output terminal 57 Transmission data input terminal 58, 60, 61, 64 Amplification unit 62 SAW matched filter for correlation demodulation 63 SAW delay line 65 Delay detection unit 66 Data recovery unit 67 FM modulation Parts 68, 70 Amplifying unit 69 Band limiting unit 71 Circuit block of receiving unit 4 72 Synchronous detecting unit 73 A / D converting unit 74 Correlation demodulating unit 75 Data reproducing unit 76 Circuit block of transmitting unit 77 Adder unit 78 Spreading code generating unit 79 reference signal generation unit 80 multiplication circuit 81 band limiting unit 82 spread modulation unit

 ─────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Ohito Okajima Kitano No. 1 Masano, Mizusawa-shi, Iwate Prefecture Hitachi Media Electronics Co., Ltd. Hitachi, Ltd. Multimedia System Development Headquarters (72) Inventor Akira Yubara, 292 Yoshida-cho, Totsuka-ku, Yokohama-shi, Kanagawa Ltd. Hitachi, Ltd. Multimedia System Development Headquarters

Claims (6)

[Claims] 1. A first wireless device for transmitting an information signal input from the outside or an information signal stored inside, and a control signal for receiving the information signal and transmitting to the first wireless device. In the wireless system including the second wireless device, the speed of the signal transmitted from the second wireless device is slower than the speed of the signal transmitted from the first wireless device. Wireless system. 2. The wireless system according to claim 1, wherein at least the information signal transmitted from the first wireless device uses spread spectrum modulation. 3. The video input device such as a video camera or a digital still camera is connected to the first wireless device, and the storage device such as a VTR or a television monitor is connected to the second wireless device. A wireless system to which an image output device such as the above and a signal processing device such as a personal computer are connected. 4. The information processing device such as one or more computers is connected to the first wireless device, and the output device such as a printer is connected to the second wireless device according to claim 1. A wireless system characterized by being performed. 5. The storage device according to claim 1, wherein a storage device is connected to the first wireless device,
An information processing device such as one or more computers is connected to the wireless device of 1. 6. The wireless device according to claim 1, wherein the second wireless device is capable of signal transmission with a plurality of wireless devices having a function equivalent to that of the first wireless device. The wireless system of 1 is capable of signal transmission with a plurality of wireless devices having the same function as that of the second wireless device.