Broadcast apparatus for closed space

• US 20070182585A1
• Filed: 09/12/2006
• Published: 08/09/2007
• Est. Priority Date: 02/07/2006
• Status: Active Grant

• Current Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Original Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Inventors: Mitsuhashi, Masaru, Nagao, Hideki
• Granted Patent: US 7,697,918 B2
• Time in Patent Office: Days
• US Class Current: 340/902
• CPC Class Codes: H04H 20/02 Arrangements for relaying broadcast information
• CPC Class Codes: H04H 20/103 Transmitter-side switching
• CPC Class Codes: H04H 20/59 for emergency or urgency
• CPC Class Codes: H04H 20/61 for local area broadcast, e.g. instore broadcast

Abstract

When a tunnel has no problem therein, a reception wave of a broadcast is retransmitted into the tunnel. At this moment, terminal registers prevent a retransmission signal from leaking from the tunnel and do not influence an adverse effect to a broadcast wave outside the tunnel. When an accident occurs in the tunnel, sensors sense this fact, and a monitoring center issues an emergency operation instruction to broadcast equipment for an emergency. At this moment, the broadcast equipment stops the retransmission of the reception wave to broadcast emergency alarm information into the tunnel and also controls transmitting antennas to emit broadcast signals to broadcast the alarm information also nearby tunnel mouths.

Claims

1. A broadcast apparatus for a closed space, comprising:

reception means for receiving a normal broadcast signal;

broadcast equipment for emergency which generates emergency information to transmit it as an emergency broadcast signal; and

transmission means for retransmitting the normal broadcast signal received by the reception means to transmit the emergency broadcast signal transmitted from the broadcast equipment for the emergency, instead of the normal broadcast signal in an emergency.

2. The broadcast apparatus for the closed space according to claim 1, wherein the transmission means increases output power in an emergency in comparison with that in normal times.

3. The broadcast apparatus for the closed space according to claim 1, wherein the transmission means transmits the emergency broadcast signal in an emergency to an adjacent area of the closed space so that its electric field strength becomes a level higher than that of a reception strength of the normal broadcast signal.

4. The broadcast apparatus for the closed space according to claim 1, wherein the transmission means transmits the normal broadcast signal received by the reception means in an emergency to an adjacent area of the closed space so that its electric field strength becomes a level higher than that of a reception strength of the emergency broadcast signal.