JPH045739U

JPH045739U -

Info

Publication number: JPH045739U
Application number: JP4591590U
Authority: JP
Priority date: 1990-04-27
Filing date: 1990-04-27
Publication date: 1992-01-20

Description

[Brief explanation of the drawing]

第１図は本考案の第１の実施例を示すブロツク
図、第２図は第１の実施例の伝送回線上の信号の
周波数帯を示す図、第３図は本考案の第２の実施
例を示すブロツク図、第４図は第２の実施例の伝
送回線上の信号の周波数帯を示す図である。１，２０……送信装置、２，３０……受信装置
、３，２１……送信画像処理部、４，２２……変
調器、５……制御部、６……トーン検出器、７，
３１……復調器、８，３２……受信画像処理部、
９，３３……トーン発生部、１１，４０……伝送
回線、２３……第１のトーン検出器、２４……第
２のトーン検出器、２５……反転回路、２６……
論理積回路、２７……送信制御部、３４……受信
制御部、１０１，２０１……入力画像信号、１０
２，２０２……送信画像データ信号、１０３，１
０４……制御信号、１０５……トーン検出信号、
１０６，３０１……受信画像データ信号、１０７
，３０２……静止画像信号、２０３〜２０５，３
０３〜３０５……制御信号、Ａ，Ｄ……送信信号
、Ｂ，Ｅ……特定周波数の信号。 Fig. 1 is a block diagram showing the first embodiment of the present invention, Fig. 2 is a diagram showing the frequency band of the signal on the transmission line of the first embodiment, and Fig. 3 is a diagram showing the second embodiment of the invention. FIG. 4, a block diagram showing an example, is a diagram showing frequency bands of signals on a transmission line in the second embodiment. 1, 20... Transmission device, 2, 30... Receiving device, 3, 21... Transmission image processing section, 4, 22... Modulator, 5... Control section, 6... Tone detector, 7,
31... Demodulator, 8, 32... Reception image processing section,
9, 33... Tone generator, 11, 40... Transmission line, 23... First tone detector, 24... Second tone detector, 25... Inverting circuit, 26...
AND circuit, 27... Transmission control section, 34... Reception control section, 101, 201... Input image signal, 10
2,202...Transmission image data signal, 103,1
04...Control signal, 105...Tone detection signal,
106, 301... Received image data signal, 107
, 302... Still image signal, 203 to 205, 3
03-305...Control signal, A, D...Transmission signal, B, E...Specific frequency signal.

Claims

[Claims for Utility Model Registration] 1. In a still image transmission device that transmits an image data signal from a transmitting device to a receiving device via a transmission line, the transmitting device modulates a carrier wave with the image data signal to generate a transmitted signal. a transmitting means for generating and transmitting the generated signal to the transmission line; a detecting means for detecting a signal of a specific frequency different from the frequency of the carrier wave on the transmission line; and a detecting means for controlling the operation of the transmitting means in accordance with the signal of the specific frequency. and a transmission control means;
A still image characterized in that the receiving device includes a receiving device that receives the transmitted signal and demodulates the image data signal, and a signal sending device that generates a signal of the specific frequency and sends it to the transmission line. Transmission device. 2. The still image transmission device according to claim 1, wherein the signal sending means generates the signal of the specific frequency at a frequency outside the frequency band of the transmission signal. 3. The detection means includes a first detector that detects the same frequency component as the signal of the specific frequency from the transmission signal, and a second detector that detects the signal of the specific frequency on the transmission line. the transmission control means performs a control operation only when the second detector detects a signal of the specific frequency on the transmission line when the first detector does not detect the same frequency component; The still image transmission device according to claim 1, wherein the still image transmission device stops. 4. The still image transmission device according to claim 3, wherein the receiving device includes reception control means for stopping the operation of the receiving means when the signal sending means sends out the signal of the specific frequency.