Transmitter for surveillance camera system

• US 20040075740A1
• Filed: 09/12/2003
• Published: 04/22/2004
• Est. Priority Date: 10/18/2002
• Status: Abandoned Application

• Current Assignee: Murakami Corporation
• Original Assignee: Murakami Corporation
• Inventors: Nagao, Mitsuyoshi, Sato, Hidenori
• Application Number:
  US10/660,721
• Publication Number:
  US 20040075740A1
• Time in Patent Office: Days
• US Class Current: 348/143
• CPC Class Codes: H04N 7/181 for receiving images from a plurality of remote sources

Abstract

An RF converter circuit 11 that constitutes a video signal superposing/power deriving unit 100 converts video signals generated from images taken by a surveillance camera 10, which derives a direct current voltage as a driving power from an antenna lead-in wire 6 through a filter circuit (LPF circuit 12), to radio-frequency signals. The radio-frequency signals are transmitted through the antenna lead-in wire 6 to a television receiver 2. Images taken by the surveillance camera 1 can be viewed on the television receiver 2 only by selecting the channel assigned to the surveillance camera 1. Accordingly, the driving power for the surveillance camera 1 is not relied upon a solar battery or secondary batteries, and wiring work therefor may be simplified.

Claims

1. A transmitter for a surveillance camera system, which transmits images taken by a surveillance camera to a television receiver, comprising:

a power deriving circuit that derives driving power for the surveillance camera from an antenna lead-in wire; and

a radio-frequency converter circuit that converts video signals generated from the images by the surveillance camera into radio-frequency signals, wherein the radio-frequency signals corresponding to the images taken by the surveillance camera are transmitted through the antenna lead-in wire to the television receiver.

2. A transmitter for a surveillance camera system according to claim 1, further comprising a video signal superposing/power deriving unit that includes the radio-frequency converter circuit and the power deriving circuit, wherein the video signal superposing/power deriving unit is provided separately from the surveillance camera;

and

wherein the video signal superposing/power deriving unit is connected with the surveillance camera and the antenna lead-in wire.

3. A transmitter for a surveillance camera system according to claim 1, further comprising a video signal superposing/power deriving unit that includes the radio-frequency converter circuit and the power deriving circuit, wherein the video signal superposing/power deriving unit is provided in the surveillance camera.

7. A transmitter for a surveillance camera system according to claim 1, further comprising:

a detection unit that detects a significant change in a location under surveillance; and

a notification unit that notifies a television viewer of detection of the significant change when the detection takes place.

4. A transmitter for a surveillance camera system, which transmits images taken by a plurality of surveillance cameras to one or more of television receivers, comprising:

a plurality of power deriving circuits that each derive driving power for corresponding one of the surveillance cameras from an antenna lead-in wire; and

a plurality of radio-frequency converter circuits that each convert video signals generated from the images by corresponding one of the surveillance cameras into radio-frequency signals, wherein the radio-frequency signals corresponding to the images taken by each of the surveillance cameras are transmitted through the antenna lead-in wire to the television receivers;

wherein radio-frequency signals from each surveillance camera are different in frequency band from those from every other surveillance camera, so that a different channel of the television receivers is assigned to the radio-frequency signals from each surveillance camera.

5. A transmitter for a surveillance camera system according to claim 4, further comprising a plurality of video signal superposing/power deriving units that each include the radio-frequency converter circuit and power deriving circuit each corresponding to one of the surveillance cameras, wherein the video signal superposing/power deriving units are provided separately from the surveillance cameras;

and

wherein the video signal superposing/power deriving units are connected with the corresponding surveillance cameras and the antenna lead-in wire.

6. A transmitter for a surveillance camera system according to claim 4, further comprising a plurality of video signal superposing/power deriving units that each include the radio-frequency converter circuit and power deriving circuit each corresponding to one of the surveillance cameras, wherein each video signal superposing/power deriving unit is provided in the corresponding surveillance camera.

8. A transmitter for a surveillance camera system according to claim 4, further comprising:

a plurality of detection units that each detect a significant change in a location under surveillance; and

a plurality of notification units that each notify a television viewer of detection of the significant change when the detection takes place.

9. A video signal superposing/power deriving unit comprising:

a power deriving circuit that derives driving power for a surveillance camera from an antenna lead-in wire; and

a radio-frequency converter circuit that converts video signals generated by the surveillance camera into radio-frequency signals, wherein the radio-frequency signals corresponding to the images taken by the surveillance camera are transmitted through the antenna lead-in wire to the television receiver.