JPH0927968A - Stereoscopic image signal transmission system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the occupancy frequency band and to facilitate the channel separation when a stereoscopic image signal is sent. SOLUTION: Both image signals received by stereoscopic TV cameras 1, 1' are converted into digital signals by image CODECs 2, 2' and signals modulated by spread spectrum modulators 3, 3' are sent from antennas 5, 5' by radio transmitters 4, 4'. The sent radio wave is received by radio receivers 7, 7' via antennas 6, 6' and converted into digital signals by spread spectrum demodulators 8, 8' and converted into an image signal by image CODECs 9, 9', from which two system signals are outputted to a monitor via an image synthesizer 10.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image transmission system for wirelessly transmitting a stereoscopic image signal.

[0002]

2. Description of the Related Art In the prior art, when attempting to wirelessly transmit a stereoscopic image, it was transmitted by frequency division or time division. Therefore, the occupied frequency band needs to be about twice the normal frequency.

[0003]

It is an object of the present invention to reduce the occupied frequency band and facilitate channel separation when transmitting a stereoscopic image.

[0004]

In order to easily enable channel separation in the same frequency band or a band in which a part thereof overlaps or is close to each other, a spread gain which is a characteristic of a spread spectrum (SS) system is used to separate channels. To facilitate. Especially when the frequency band used is limited,
By using the spread gain of the SS method and the polarization plane effect of the antenna, it is possible to easily separate two channels with a small C / N.

When transmitting a stereoscopic image signal, it is necessary to transmit image signals of two channels at the same time. In the conventional method, generally, transmission is performed by frequency division, so that a wide occupied band of frequency is required, and separation between channels is not easy. Therefore, the separation between channels is facilitated by using the SS modulation method, which enables separation between channels with less C / N by using different spreading codes.
Especially when the frequency band to be used is limited, it is possible to easily separate the two channels with a small C / N by using the spreading gain of the SS modulation method and the polarization plane effect of the antenna together. Further, by using the ISM band as the used band, it is not necessary to apply for a wireless station, the restriction on the installation place is reduced, and the communication with the mobile body becomes possible.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is an example of a stereoscopic image transmission system using the present invention, in which (a) is a transmitter and (b) is a receiver. The left and right video signals input from the stereoscopic TV cameras 1 and 1'are converted into digital signals by the image codecs 2 and 2 ',
The signals modulated by the spread spectrum modulators 3 and 3'are transmitted by the radio transmitters 4 and 4'through the antennas 5 and 5 ', respectively. The transmitted radio waves are received by radio receivers 7, 7'through antennas 6, 6 ', converted into digital signals by spread spectrum demodulators 8, 8', and then converted into video signals by image codecs 9, 9 '. To be converted. The image synthesizer 1 uses the two systems of video signals output by the image codecs 9 and 9 '.
Output to monitor 11 through 0. Since the antennas 5 and 5'and the antennas 6 and 6'are installed at almost the same position, unnecessary radio waves are mixed in the antenna with a C / N ratio of 0 dB.
Separation becomes difficult except for the SS modulation method. Also in the SS method, if the degree of spreading is small, the spreading gain is small,
Considering various variations, the system margin decreases and it becomes difficult to put into practical use. In such a case, for example, by using the antennas 5 and 6 for horizontal polarization and the antennas 5'and 6'for vertical polarization, it is possible to transmit a stereoscopic image signal even in the same frequency band. The frequency used at this time is IS
Using the M band makes it unnecessary to apply for a wireless station, reduces restrictions on installation locations, and enables communication with mobile units.

[0007]

According to the present invention, when transmitting a stereoscopic image signal, the occupied frequency band can be reduced and the left and right image signals can be easily separated from each other.

[Brief description of drawings]

FIG. 1 is a block diagram showing a stereoscopic image signal transmission system.

[Explanation of symbols]

1,1 'TV camera, 2,2' image codec,
3,3 'spread spectrum modulator, 4,4' wireless transmitter, 5,5 ', 6,6' antenna, 7,7 'wireless receiver, 8,8' spread spectrum demodulator, 9,9 '
Image codec, 10 image synthesizer, 11 video monitor.

Claims (3)

[Claims] 1. A three-dimensional image signal transmission system for transmitting two-channel three-dimensional image signals by radio, wherein two PN signals are used to spread-spectrum-modulate each channel signal and carry them on a carrier wave. . 2. The stereoscopic image signal according to claim 1, wherein radio waves having different planes of polarization are used for each channel transmission, so that the signals are transmitted in the same frequency band or in a transmission band of carrier waves in which a part overlaps or approaches. Transmission system. 3. A stereoscopic image signal transmission system, wherein the transmission band according to claim 2 is used in an ISM band (Industrial scientific Medical) which does not require a wireless station application.